Patent Publication Number: US-2019183670-A1

Title: Mouthpiece

Description:
TECHNICAL FIELD 
     The present disclosure relates to a mouthpiece. 
     BACKGROUND ART 
     Hitherto, medical mouthpieces have been employed in the treatment of sleep apnea syndrome, temporomandibular joint disorders, and the like. Normally a gap naturally arises between upper and lower teeth in a closed mouth state, and there are individual patient-related differences in the gap between the upper and lower teeth. There are accordingly known methods, for example, to adjust the gap between a maxillary piece and a mandibular piece of a mouthpiece by employing a vertical adjustment member that is bitten between anterior portions of the maxillary and mandibular pieces. 
     Moreover, a mouthpiece is disclosed in Non-Patent Document 1 that enables a gap between a maxillary piece and a mandibular piece of a mouthpiece to be adjusted by fixing a vertical adjustment member to an opposing face (namely, to an occlusal surface) of the maxillary piece opposing the mandibular piece by using screws. 
     Moreover, a dental brace is disclosed, for example as in Patent Document 1, that includes a maxillary brace that fits to maxillary dentition, a mandibular brace that fits to mandibular dentition, and a bite system that connects the maxillary brace and the mandibular brace together. Furthermore, a mouthpiece is disclosed in Non-Patent Document 2 that has a bite adjustment tool to adjust the vertical dimension of occlusion. 
     LIST OF DOCUMENTS 
     
         
         Patent Document 1: Specification of US Patent Application Publication No. 2007/0224567. 
         Non-Patent Document 1: “B.O.S.S. Bite Opening Smart Shims” by Tompkins Dental Supply Inc., AADSM 25th Annual Meeting, Jun. 10, 2016. 
         Non-Patent Document 2: pages 28 to 34 of “Dental Sleep Practice, spring 2016”, Mar. 1, 2016. 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     In cases in which a vertical adjustment member is bitten by anterior parts of a maxillary piece and a mandibular piece, measures need to be taken to prevent dropout of the vertical adjustment member, such as exposing an anchor portion for anchoring the vertical adjustment member at a labial side, making the exposed anchor portion larger than the bitten portion, and the like. There is accordingly a concern regarding a detrimental effect on an appearance, and also regarding a feeling of discomfort arising due to the anchor portion, to which the height adjustment member is anchored, abutting inside faces of the cheeks and lips. 
     Moreover, as disclosed in Non-Patent Document 1, in cases in which the vertical adjustment member is fixed to the opposing face of the maxillary piece, a thickness of the opposing face needs to be increased in order to form an anchor portion (namely female threaded hole) at the opposing face to fasten a screw. 
     Moreover, with a dental brace such as that disclosed in Patent Document 1, there is a concern that a gap between upper and lower dentition cannot be adjusted, and regarding a feeling of discomfort arising when wearing the dental brace due to the maxillary brace and the mandibular brace being held in a state abutting each other. 
     Furthermore, with the mouthpiece disclosed in Non-Patent Document 2, there is a concern regarding the bite adjustment tool dropping out from the mouthpiece due to the bite adjustment tool not being fixed to the mouthpiece. Moreover, the size of the bite adjustment tool is enlarged in order to prevent the bite adjustment tool from being swallowed by a patient if it were to drop out. This leads to a feeling of discomfort arising when the mouthpiece is being worn. 
     An object of a first aspect of the present disclosure is accordingly to provide a mouthpiece that enables an anchor portion of a vertical adjustment member to be suppressed from projecting out to an outer wall face side and an opposing face side of the mouthpiece. 
     Moreover, an object of a second aspect of the present disclosure is to provide a mouthpiece that enables a vertical adjustment member to be made more compact, while also suppressing dropout of the vertical adjustment member. 
     Moreover, an object of a third aspect of the present disclosure is to provide a mouthpiece that enables a relative position adjustment member including a vertical adjustment member to be made more compact, while also suppressing dropout of the relative position adjustment member. 
     Solution to Problem 
     The following exemplary embodiments &lt;1&gt; to &lt;9&gt; are examples of the first aspect of the present disclosure. 
     The following exemplary embodiments &lt;10&gt; to &lt;17&gt; are examples of the second aspect of the present disclosure. 
     The following exemplary embodiments &lt;18&gt; to &lt;28&gt; are examples of the third aspect of the present disclosure. 
     &lt;1&gt; A mouthpiece including a maxillary piece that is mounted to maxillary dentition, a mandibular piece that is mounted to mandibular dentition, a positioning member that positions the mandibular piece with respect to the maxillary piece, an anchor base that includes an anchor portion and is formed at an inner wall face of at least one of the maxillary piece or the mandibular piece, and a vertical adjustment member that includes a mounting portion mounted to the anchor portion of the anchor base, and a clamped portion clamped between the maxillary piece and the mandibular piece. 
     According to the above configuration &lt;1&gt;, the mounting portion of the vertical adjustment member is mounted to the anchor portion of the anchor base, and the clamped portion of the vertical adjustment member is clamped between the maxillary piece and the mandibular piece. This enables a gap to be formed by the vertical adjustment member between the maxillary piece and the mandibular piece, while also suppressing dropout of the vertical adjustment member. 
     The anchor portion can be suppressed from projecting out to an outer wall face side and an opposing face side of the maxillary piece or the mandibular piece due to the anchor base being formed at the inner wall face of at least one of the maxillary piece or the mandibular piece. 
     &lt;2&gt; The mouthpiece described in &lt;1&gt;, wherein the anchor base is formed at a posterior side of a dentition of at least one of the maxillary piece or the mandibular piece. 
     Generally, a width of opposing faces is larger at a posterior side (for example, tooth positions  4  to  8 ) of the maxillary piece and the mandibular piece than an anterior side (for example, tooth positions  1  to  3 ) thereof, and bite closure force from the upper and lower teeth is accordingly more easily applied to the posterior side when the mouth is closed. Thus according to the above configuration in &lt;2&gt;, by forming the anchor base at the posterior side of the dentition of the maxillary piece or the mandibular piece, the vertical adjustment member is easily clamped between the maxillary piece and the mandibular piece, enabling dropout of the vertical adjustment member to be suppressed. 
     Furthermore, by mounting the vertical adjustment member at the posterior side of the dentition of the maxillary piece or the mandibular piece, obstruction of tongue movement by the vertical adjustment member when the mouth is closed can also be suppressed more than configurations in which the vertical adjustment member is mounted at an anterior side of the dentition. 
     &lt;3&gt; The mouthpiece described in &lt;1 or &lt;2&gt;, wherein, in a mounted state of the mounting portion of the vertical adjustment member to the anchor portion of the anchor base, the vertical adjustment member has an asymmetrical shape with respect to a plane bisecting the vertical adjustment member between the inner wall face side and an outer wall face side of the maxillary piece or the mandibular piece. 
     According to the above configuration &lt;3&gt;, the vertical adjustment member is configured with an asymmetrical shape with respect to the plane bisecting the vertical adjustment member between the inner wall face side and the outer wall face side of the maxillary piece or the mandibular piece. This enables, for example, a higher degree of flexibility for the shape of the vertical adjustment member, such as by shaping the clamped portion of the vertical adjustment member to match jaw shape or the like. 
     Note that in the present specification “a plane bisecting the vertical adjustment member” indicates a plane that is orthogonal to the main plane of the clamped portion of the vertical adjustment member (namely, orthogonal to a plane opposing the opposing face of the maxillary piece or the mandibular piece) and that bisects a surface area of the main plane of the clamped portion. 
     &lt;4&gt; The mouthpiece described in &lt;3&gt;, wherein, in a mounted state of the mounting portion of the vertical adjustment member to the anchor portion of the anchor base, the mounting portion is provided at the vertical adjustment member at the inner wall face side of the maxillary piece or the mandibular piece. 
     According to the above configuration &lt;4&gt; due to the mounting portion being provided at the inner wall face side of the vertical adjustment member, the mounting portion can be better suppressed from projecting to the outer wall face side of the maxillary piece or the mandibular piece and interfering with a positioning member or the like than in configurations in which the mounting portion is provided at the center or outer wall face side of the vertical adjustment member. 
     &lt;5&gt; The mouthpiece described in any one of &lt;1&gt; to &lt;4&gt;, wherein the anchor portion of the anchor base is configured by an indentation, and the mounting portion of the vertical adjustment member is configured as a protrusion that fits into the indentation. 
     According to the above configuration &lt;5&gt;, the anchor portion is configured as the indentation and the mounting portion is a protrusion. This enables the vertical adjustment member to be easily anchored to the anchor base and dropout of the vertical adjustment member to be suppressed by fitting the protrusion into the indentation. 
     &lt;6&gt; The mouthpiece described in any one of &lt;1&gt; to &lt;4&gt;, wherein the mounting portion of the vertical adjustment member is configured as a through hole that a screw is inserted through, and the anchor portion of the anchor base is a female threaded hole that the screw, inserted through the through hole, is screwed into. 
     According to the above configuration &lt;6&gt;, the mounting portion is configured as the through hole, and the anchor portion is configured as the female threaded hole. This enables the vertical adjustment member to be easily anchored to the anchor base and dropout of the vertical adjustment member to be suppressed by screwing the screw, inserted through the through hole, into the female threaded hole. 
     &lt;7&gt; The mouthpiece described in &lt;5&gt;, wherein the indentation includes an opening portion at an opposing face of the anchor base, opposing at least one of the maxillary piece or the mandibular piece, and in plan view of the opening portion of the indentation, an imaginary line along a length direction of the opening portion intersects with a center line of a dentition of the maxillary piece or the mandibular piece. 
     When the mouthpiece is being worn, the air (namely, inhaled air and exhaled air) flows between the maxillary piece and the mandibular piece each time the patient breaths. According to the above configuration &lt;7&gt;, the imaginary line along the length direction of the opening portion of the indentation intersects with the center line of dentition, namely, intersects with a direction of airflow. This enables the protrusion of the vertical adjustment member, fitted into the indentation, to be better suppressed from dropping out from the indentation due to the airflow than configurations in which the imaginary line does not intersect with the center line. 
     &lt;8&gt; The mouthpiece described in &lt;5&gt;, wherein the indentation includes an opening portion at an inner wall face of the anchor base, and when the anchor base is viewed from an opposing face side of the maxillary piece or the mandibular piece where they oppose each other, an imaginary line along a length direction of the opening portion intersects with a center line of a dentition of the maxillary piece or the mandibular piece. 
     According to the above configuration &lt;8&gt; the imaginary line along the length direction of the opening portion of the indentation intersects with the center line of the dentition, namely with the direction of airflow. This enables the protrusion of the vertical adjustment member, fitted into the indentation, to be better suppressed from dropping out from the indentation due to the airflow than configurations in which the imaginary line does not intersect with the center line. 
     &lt;9&gt; The mouthpiece described in &lt;5&gt;, wherein the indentation includes an opening portion at an inner wall face of the anchor base, and an imaginary line along a length direction of the opening portion intersects with an imaginary plane parallel to an opposing face of the maxillary piece or the mandibular piece where they oppose each other. 
     According to the above configuration &lt;9&gt;, the imaginary line along the length direction of the opening portion of the indentation intersects with the imaginary plane parallel to the opposing face of the mouthpiece, namely, intersect with the airflow direction. This enables the protrusion of the vertical adjustment member, fitted into the indentation, to be better suppressed from dropping out from the indentation due to the airflow than configurations in which the imaginary line does not intersect with the imaginary plane. 
     &lt;10&gt; A mouthpiece including a maxillary piece that is mounted to maxillary dentition, a mandibular piece that is mounted to mandibular dentition, a positioning member that positions the mandibular piece with respect to the maxillary piece, an anchor portion that includes a mount and that is formed at at least one location or more at an outer periphery of at least one of the maxillary piece or the mandibular piece, or that is formed on an opposing face of the maxillary piece or the mandibular piece where they oppose each other, and a vertical adjustment member that is mounted to the mount of the anchor portion and that is clamped between the maxillary piece and the mandibular piece. 
     According to the above configuration &lt;10&gt;, the vertical adjustment member is mounted to the mount of the anchor portion. This enables the vertical adjustment member to be clamped between the maxillary piece and the mandibular piece, while also enabling dropout of the vertical adjustment member to be suppressed. Moreover, the gap between the maxillary piece and the mandibular piece can be adjusted by replacing the vertical adjustment member. 
     Furthermore, due to the mount of the anchor portion being formed at at least one location or more at the outer periphery of the maxillary piece or the mandibular piece, or the mount of the anchor portion being formed at the opposing face, there is accordingly a lower risk of being swallowed by the patient even if the vertical adjustment member were to drop out than configurations in which the mount is formed at an inner wall face of the maxillary piece or the mandibular piece. This enables the vertical adjustment member to be made more compact, as the vertical adjustment member does not needing to be enlarged. 
     Note that in the present specification “an outer periphery of the maxillary piece or the mandibular piece” indicates the outer wall face of the maxillary piece or the mandibular piece as well as a portion including a projection, stopper portion, or the like formed at the outer wall face. 
     &lt;11&gt; The mouthpiece described in &lt;10&gt;, wherein the mount is formed at at least one location or more at an outer side a line passing through width direction centers of the opposing face. 
     According to the above configuration &lt;11&gt;, the mount is disposed at the outer side of the line passing through the width direction centers of the opposing face of the maxillary piece or the mandibular piece, namely, at the outer wall face side of the maxillary piece or the mandibular piece. This enables a risk of being swallowed by the patient to be lowered even if the vertical adjustment member were to drop out than configurations in which the mount is disposed at an inner side of the line passing through the centers. 
     &lt;12&gt; The mouthpiece described in &lt;10&gt; or &lt;11&gt;, wherein the anchor base is formed at an outer wall face of the maxillary piece or the mandibular piece so as to project outer side than other portions of the outer wall face, and the anchor portion is formed at the anchor base. 
     According to the above configuration, due to the anchor portion being formed at the anchor base, that is formed projecting out from the outer wall face of the maxillary piece or the mandibular piece, the vertical adjustment member can be prevented from interfering with the dentition when the vertical adjustment member is mounted to the anchor portion. 
     &lt;13&gt; The mouthpiece described in any one of &lt;10&gt; to &lt;12&gt;, wherein the positioning member is attached to a posterior side of the dentition of the maxillary piece and the mandibular piece, and the anchor portion is formed at at least one location or more at an anterior side of the dentition of the maxillary piece or the mandibular piece from the positioning member. 
     According to the above configuration &lt;13&gt;, the positioning member is attached at the posterior side of the dentition of the maxillary piece and the mandibular piece, and the anchor portion is formed at the maxillary piece or the mandibular piece at the anterior side from the positioning member. Thus when the vertical adjustment member is mounted to the anchor portion, the vertical adjustment member can be prevented from interfering with the positioning member. 
     &lt;14&gt; The mouthpiece described in &lt;10&gt; or &lt;11&gt;, wherein the positioning member includes a wing portion that is formed at an outer wall face of one of the maxillary piece or the mandibular piece and extends in a direction toward another of the maxillary piece or the mandibular piece, and a stopper portion that is formed at an outer wall face of the other of the maxillary piece or the mandibular piece at a position at a posterior side from the wing portion and that restricts movement to the posterior side of the wing portion, and the mount of the anchor portion is formed at at least one location or more at a face of the stopper portion opposing the maxillary piece or the mandibular piece. 
     The above configuration &lt;14&gt; enables the mandibular piece to be positioned by the wing portion and the stopper portion so as not to move to the posterior side with respect to the maxillary piece. Moreover, due to the anchor portion being formed at the stopper portion, there is no need to form the anchor portion at the outer wall face or opposing face of the maxillary piece or the mandibular piece. 
     &lt;15&gt; The mouthpiece described in any one of &lt;10&gt; to &lt;14&gt;, wherein the anchor portion is configured as a through hole, and the vertical adjustment member includes a protrusion, a length of the protrusion in an extension direction being shorter than a depth of the through hole, and the protrusion being fit into the through hole. 
     According to the above configuration &lt;15&gt;, due to the anchor portion being configured as a through hole penetrating through the maxillary piece or the mandibular piece, cleaning is easier than configurations in which the anchor portion is bottomed. Moreover, due to the length in the extension direction of the protrusion being shorter than the depth of the through hole, the protrusion can be prevented from being exposed from the through hole and interfering with the dentition. 
     &lt;16&gt; The mouthpiece described in &lt;15&gt;, wherein the vertical adjustment member has left-right symmetry with respect to a plane bisecting the protrusion along the extension direction of the protrusion. 
     According to the above configuration &lt;16&gt;, due to the vertical adjustment member having left-right symmetry with respect to the plane bisecting the protrusion, for example, a common spacer can be employed on the left and right in cases in which vertical adjustment members are anchored to anchor portions formed at two locations at left and right of the dentition of the maxillary piece or the mandibular piece. 
     &lt;17&gt; The mouthpiece described in &lt;15&gt; or &lt;16&gt;, wherein a hooked portion employed for retention is formed at a leading end of the protrusion. 
     According to the above configuration &lt;17&gt;, due to the hooked portion, employed for retention, being formed at the leading end of the protrusion of the vertical adjustment member, the vertical adjustment member can be suppressed from dropping out from the through hole configuring the anchor portion. 
     &lt;18&gt; A mouthpiece including a maxillary piece that is mounted to maxillary dentition, a mandibular piece that is mounted to mandibular dentition, a wing portion that is provided at an outer wall face of one of the maxillary piece or the mandibular piece and that extends in a direction toward another of the maxillary piece or the mandibular piece, a stopper portion that is provided at an outer wall face of the other of the maxillary piece or the mandibular piece and that restricts movement to a posterior side of the dentition of the mandibular piece by abutting the wing portion, and a relative position adjustment member that is provided at the wing portion or the stopper portion to adjust a relative position of the maxillary piece and the mandibular piece. 
     According to the above configuration &lt;18&gt;, the mandibular piece can be positioned by the wing portion and the stopper portion so that movement to the posterior side of the dentition does not occur with respect to the maxillary piece. Moreover, the relative position of the maxillary piece and the mandibular piece can be adjusted by the relative position adjustment member provided at the wing portion or the stopper portion and clamped between the maxillary piece and the mandibular piece. 
     Moreover, the wing portion or the stopper portion that is provided with the relative position adjustment member is strongly fixed to the maxillary piece or the mandibular piece. This enables the size of the relative position adjustment member itself to be made smaller, as well as enabling dropout of the relative position adjustment member to be suppressed. Note that due to the wing portion and the stopper portion being provided at the outer wall faces of the maxillary piece and the mandibular piece, a risk of being swallowed by the patient can be lowered even if the relative position adjustment member were to drop out when the mouthpiece is being worn than in configurations in which the wing portion and stopper portion are provided on the inner wall face. 
     &lt;19&gt; The mouthpiece described in &lt;18&gt;, wherein the wing portion is provided at an outer wall face of the mandibular piece and extends toward the maxillary piece, and the stopper portion is provided at an outer wall face of the maxillary piece at a position at a posterior side from the wing portion. 
     According to the above configuration &lt;19&gt;, the mandibular piece can be positioned so that movement to a posterior side with respect to the maxillary piece does not occur due to the wing portion, provided at the mandibular piece, abutting the stopper portion located at the posterior side from the wing portion. 
     &lt;20&gt; The mouthpiece described in &lt;18&gt; or &lt;19&gt;, wherein at least a portion of the relative position adjustment member is clamped between the maxillary piece and the mandibular piece. 
     According to the above configuration &lt;20&gt;, the gap between the maxillary piece and the mandibular piece can be adjusted by the relative position adjustment member being clamped between the maxillary piece and the mandibular piece. 
     &lt;21&gt; The mouthpiece described in &lt;20&gt;, wherein the relative position adjustment member is formed integrally to the wing portion, and the wing portion is detachably attached to a wing attachment portion provided at the maxillary piece or the mandibular piece. 
     According to the above configuration &lt;21&gt;, the wing portion, formed integrally with the relative position adjustment member, is detachably attached to the wing attachment portion. This enables the gap between the maxillary piece and the mandibular piece to be adjusted by replacing the wing portion with another equipped with a relative position adjustment member of a different vertical dimension. 
     &lt;22&gt; The mouthpiece described in &lt;21&gt;, wherein the wing attachment portion is provided at an outer wall face of the maxillary piece or the mandibular piece. 
     According to the above configuration &lt;22&gt;, the wing attachment portion is provided at an outer wall face of the maxillary piece or the mandibular piece. This enables the vertical dimension of the wing portion itself to be adjusted by attaching wing portions of a different vertical dimension to the wing attachment portion. 
     &lt;23&gt; The mouthpiece described in &lt;21&gt; or &lt;22&gt;, wherein an attachment face for the wing portion at the wing attachment portion lies in substantially a same plane as an opposing face of the maxillary piece opposing the mandibular piece or an opposing face of the mandibular piece opposing the maxillary piece. 
     According to the above configuration &lt;23&gt;, the attachment face at the wing attachment portion is in substantially a same plane as the opposing face of the maxillary piece or the mandibular piece. This makes for easier cleaning of the attachment face at the wing attachment portion and the opposing face of the maxillary piece or the mandibular piece when maintenance is performed on the mouthpiece. 
     &lt;24&gt; The mouthpiece described in any one of &lt;18&gt; to &lt;20&gt;, wherein the relative position adjustment member is detachably attached to an anchor portion of the wing portion, and the wing portion is formed integrally to the maxillary piece or the mandibular piece. 
     According to the above configuration &lt;24&gt;, the relative position adjustment member is detachably attached to the anchor portion of the wing portion. This enables the relative position of the maxillary piece and the mandibular piece to be adjusted by replacing the relative position adjustment member. 
     &lt;25&gt; The mouthpiece described in &lt;20&gt;, wherein the relative position adjustment member is formed integrally to the stopper portion, and the stopper portion is detachably attached to the stopper attachment portion provided at the maxillary piece or the mandibular piece. 
     According to the above configuration &lt;25&gt;, the stopper portion formed integrally with the relative position adjustment member is detachably attached to the stopper attachment portion. This enables the gap between the maxillary piece and the mandibular piece to be adjusted by replacing the stopper portion with another equipped with a relative position adjustment member of a different vertical dimension. 
     &lt;26&gt; The mouthpiece described in &lt;25&gt;, wherein the stopper attachment portion includes a rail member provided at an outer wall face of the maxillary piece or the mandibular piece, and a rail groove that the rail member fits into is formed at the stopper portion. 
     According to the above configuration &lt;26&gt;, fitting the rail member of the stopper attachment portion into the rail groove of the stopper portion enables the stopper portion to be easily attached to or detached from the stopper attachment portion, and also enables the stopper portion to be suppressed from dropping out from the stopper attachment portion. 
     &lt;27&gt; The mouthpiece described in any one of &lt;18&gt; to &lt;20&gt;, wherein the relative position adjustment member is detachably attached to the anchor portion of the stopper portion, and the stopper portion is formed integrally to the maxillary piece or the mandibular piece. 
     According to the above configuration &lt;27&gt;, the relative position adjustment member is detachably attached to the stopper portion. This enables the relative position of the maxillary piece and the mandibular piece to be adjusted by replacing the relative position adjustment member. 
     &lt;28&gt; The mouthpiece described in &lt;24&gt; or &lt;27&gt;, wherein the anchor portion is provided at an abutting face of the wing portion abutting the stopper portion, or at an abutting face of the stopper portion abutting the wing portion, and at least a portion of the relative position adjustment member is clamped by the wing portion and the stopper portion. 
     According to the above configuration &lt;28&gt;, the relative position adjustment member being clamped by the wing portion and the stopper portion when the mouthpiece is being worn enables the relative position adjustment member to be suppressed from dropping out from the anchor portion. Moreover, the relative position adjustment member is easily attached to or detached from the anchor portion when the mouthpiece is not being worn. 
     Advantageous Effects 
     The first aspect enables an anchor portion of a vertical adjustment member to be suppressed from projecting to an outer wall face side or an opposing face side of a mouthpiece. 
     The second aspect enables a mouthpiece to be provided in which dropout of a vertical adjustment member can be suppressed and the vertical adjustment member can be made more compact. 
     The third aspect enables a mouthpiece to be provided in which dropout of a relative position adjustment member including a vertical adjustment member can be suppressed and the relative position adjustment member can be made more compact. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a front view illustrating vertical adjustment members of a mouthpiece of a first exemplary embodiment of a first aspect in a pre-attachment state. 
         FIG. 2A  is a front view illustrating the vertical adjustment members of the mouthpiece of the first exemplary embodiment of the first aspect in a post-attachment state. 
         FIG. 2B  is bottom view of a maxillary piece of the mouthpiece of the first exemplary embodiment of the first aspect in a state viewed from an opposing face side. 
         FIG. 3A  is a front view illustrating vertical adjustment members of a mouthpiece of a second exemplary embodiment of the first aspect in a pre-attachment state. 
         FIG. 3B  is a front view illustrating the vertical adjustment members of the mouthpiece of the second exemplary embodiment of the first aspect in a post-attachment state. 
         FIG. 4A  is a bottom view of a maxillary piece of the mouthpiece of the second exemplary embodiment of the first aspect in a state viewed from an opposing face side. 
         FIG. 4B  is a cross-section taken along line A-A of  FIG. 3B .  FIG. 5A  is a front view illustrating vertical adjustment members of a mouthpiece of a third exemplary embodiment of the first aspect in pre-attachment state. 
         FIG. 5B  is a front view illustrating the vertical adjustment members of the mouthpiece of the third exemplary embodiment of the first aspect in a post-attachment state. 
         FIG. 6A  is a front view illustrating vertical adjustment members of a mouthpiece of a first exemplary embodiment of a second aspect in a pre-attachment state. 
         FIG. 6B  is a front view illustrating the vertical adjustment members of the mouthpiece of the first exemplary embodiment of the second aspect in a post-attachment state. 
         FIG. 7A  is a front view illustrating a vertical adjustment member of a mouthpiece of a second exemplary embodiment of the second aspect in a pre-attachment state. 
         FIG. 7B  is a front view illustrating the vertical adjustment member of the mouthpiece according to the second exemplary embodiment of the second aspect in a post-attachment state. 
         FIG. 8A  is a front view illustrating vertical adjustment members of a mouthpiece according to a third exemplary embodiment of the second aspect in a pre-attachment state. 
         FIG. 8B  is a side view illustrating the vertical adjustment member of the mouthpiece according to the third exemplary embodiment of the second aspect in a post-attachment state. 
         FIG. 9A  is a perspective view illustrating a portion of a mouthpiece according to a modified example of the second aspect. 
         FIG. 9B  is a perspective view illustrating a portion of a mouthpiece according to a modified example of the second aspect. 
         FIG. 9C  is a perspective view illustrating a portion of a mouthpiece according to a modified example of the second aspect. 
         FIG. 10A  is a front view illustrating relative position adjustment members of a mouthpiece according to a first exemplary embodiment of a third aspect in a pre-attachment state. 
         FIG. 10B  is a side view illustrating a relative position adjustment member of the mouthpiece according to the first exemplary embodiment of the third aspect in a post-attachment state. 
         FIG. 11A  is a side view illustrating a relative position adjustment member of a mouthpiece according to a second exemplary embodiment of the third aspect in a pre-attachment state. 
         FIG. 11B  is a side view illustrating the relative position adjustment member of the mouthpiece according to the second exemplary embodiment of the third aspect in a post-attachment state. 
         FIG. 12A  is a side view illustrating a relative position adjustment member of a mouthpiece according to a third exemplary embodiment of the third aspect in a pre-attachment state. 
         FIG. 12B  is a side view illustrating the relative position adjustment member of the mouthpiece according to the third exemplary embodiment of the third aspect in a post-attachment state. 
         FIG. 13A  is a side view illustrating a relative position adjustment member of a mouthpiece according to a fourth exemplary embodiment of the third aspect in a pre-attachment state. 
         FIG. 13B  is a side view illustrating the relative position adjustment member of the mouthpiece according to the fourth exemplary embodiment of the third aspect in a post-attachment state. 
         FIG. 14A  is a side view illustrating a relative position adjustment member of a modified example of a mouthpiece according to the second exemplary embodiment of the third aspect in a pre-attachment state. 
         FIG. 14B  is a side view illustrating the relative position adjustment member of the modified example of a mouthpiece according to the second exemplary embodiment of the third aspect in a post-attachment state. 
         FIG. 15A  is a side view illustrating a relative position adjustment member of a modified example of a mouthpiece according to the fourth exemplary embodiment of the third aspect in a pre-attachment state. 
         FIG. 15B  is a side view illustrating the relative position adjustment member of the modified example of the mouthpiece according to the fourth exemplary embodiment of the third aspect in a post-attachment state. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     In the present specification, “an outer wall face side” indicates a buccal side (namely, an outer side) when a mouthpiece is being worn, and “an inner wall face side” indicates a lingual side (namely, an inner side) when the mouthpiece is being worn. Moreover, “an anterior side of dentition” indicates a front teeth (e.g. tooth positions  1  to  3 ) side, namely a labial side when the mouthpiece is being worn, and “a posterior side of dentition” indicates a back teeth (e.g. tooth positions  4  to  8 ) side, namely a palatal side when the mouthpiece is being worn. 
     Explanation follows regarding examples of a first aspect to a third aspect of the present disclosure, with reference to the drawings. The present disclosure is not limited to embodiments illustrated in the drawings. Note that sizes of members in each of the drawings are only schematic, and relative size relationships between members are not limited thereto. 
     First Aspect 
     A mouthpiece according to a first aspect of the present disclosure includes a maxillary piece that is mounted to maxillary dentition, a mandibular piece that is mounted to mandibular dentition, a positioning member that positions the mandibular piece with respect to the maxillary piece, an anchor base that includes an anchor portion, and that is formed at an inner wall face of at least one of the maxillary piece or the mandibular piece, and a vertical adjustment member that includes a mounting portion mounted to the anchor portion of the anchor base, and a clamped portion clamped between the maxillary piece and the mandibular piece. 
     In the first aspect, the anchor base is formed at the inner wall face of at least one of the maxillary piece or the mandibular piece. This enables the anchor portion to be suppressed from projecting out to an outer wall face side and an opposing face side from the maxillary piece or the mandibular piece. 
     Note that in the following first aspect, configuration referred to as “an anchor portion” in the disclosure of Japanese Patent Application No. 2016-224519 is referred to as “the anchor base” herein, and configuration referred to as “a mount” therein is referred to as “the anchor portion” herein. 
     First Exemplary Embodiment 
     Explanation follows regarding a mouthpiece according to a first exemplary embodiment of the first aspect, with reference to  FIG. 1  to  FIG. 2B . 
     A mouthpiece  10  of the present exemplary embodiment is, for example, a mouthpiece employed for sleep apnea syndrome so as to reduce or prevent snoring and bruxism, and breathing interruptions or the like while sleeping. As illustrated in  FIG. 1 , the mouthpiece  10  includes a maxillary piece  12  worn at maxillary dentition, and a mandibular piece  14  worn at mandibular dentition. 
     The maxillary piece  12  and the mandibular piece  14  may, for example, be configured from an acrylic-based resin having a modulus of elasticity of approximately 2150 MPa in bending tests according to JIS T6501. Examples of resin materials that may be employed for the maxillary piece  12  and the mandibular piece  14  also include polyester-based resins, polycarbonate-based resins, urethane-based resins, vinyl acetate-based resins, polyamide-based resins, and the like. 
     Metal upper attachment portions  16  are provided at an outer wall face  12 A of the maxillary piece  12 , so as to project out from the outer wall face  12 A at left and right posterior sides (tooth positions  6  to  7  in the present exemplary embodiment) as viewed from a center of a dentition. Metal lower attachment portions  18  are provided at an outer wall face  14 A of the mandibular piece  14 , so as to project out from the outer wall face  14 A at left and right posterior sides (at tooth positions  3  to  4  in the present exemplary embodiment) as viewed from a center of a dentition. 
     The right upper attachment portion  16  and the right lower attachment portion  18 , and the left upper attachment portion  16  and the left lower attachment portion  18 , are respectively coupled together by metal coupling members  20  capable of pivoting. The coupling members  20  are positioning members to position the mandibular piece  14  so that movement to a posterior side does not occur with respect to the maxillary piece  12 . The maxillary piece  12  and the mandibular piece  14  are coupled together by the pair of coupling members  20  so as to be capable of opening and closing. 
     In the mouthpiece  10  of the present exemplary embodiment, the upper attachment portion  16  is at the posterior side from (namely, at the posterior dentition side of) the lower attachment portion  18  as viewed from the center of dentition. Namely, the mouthpiece  10  is configured as a push-type mouthpiece that when worn pushes the mandibular piece  14  (and hence the mandible) forward using the coupling members  20 . 
     The coupling members  20  each includes a length adjustment mechanism  22 , a sliding mechanism  24 , and eyelets  26  attached to the upper attachment portion  16  and the lower attachment portion  18 . The length adjustment mechanisms  22  each includes a nut  28  and a male screw  30  screwed into the nut  28 . A screw amount of the male screw  30  is adjusted by rotating the nut  28  to adjust a length of each coupling member  20  in a continuous manner. 
     The sliding mechanisms  24  each includes a sleeve  32  and a rod  34 . The coupling members  20  are able to follow the maxillary piece  12  and the mandibular piece  14  by the rods  34  sliding inside the sleeves  32  to match movement of the maxillary piece  12  and the mandibular piece  14 . A distance between the upper attachment portion  16  and the lower attachment portion  18  (a distance between respective centers) is adjusted by the coupling members  20  so as to be between about 18 mm and about 50 mm. 
     Anchor bases  38  including anchor portions  36  are respectively formed so as to project out from an inner wall face  12 B at the left and right sides (at tooth positions  6  to  7  in the present exemplary embodiment) of the maxillary piece  12  as viewed from a center of dentition. The anchor portions  36  each is formed as a substantially rectangular shaped recess, and includes an elongated opening portion  36 A at a lower face of the anchor base  38 , namely, at an opposing face  38 A that opposes the mandibular piece  14 . 
     As illustrated in  FIG. 2B , an imaginary line K, running along a length direction of each of the opening portions  36 A when viewing the opening portions  36 A of the anchor portion  36  in plan view, extends in a direction approaching a dentition center line L of the maxillary piece  12  on progression from the posterior side toward the anterior side of the dentition. The imaginary lines K each intersects with the center line L. Namely, a length direction (imaginary line K) of each of the opening portions  36 A of the anchor portions  36  is not parallel to the center line L. 
     Note that angles of the imaginary lines K illustrated in  FIG. 2B  are an example thereof. The imaginary lines K may each be at any angle not parallel to the center line L. However, an angle formed between each of the imaginary lines K and the center line L is preferably from 5 degrees to 45 degrees, is more preferably from 5 degrees to 30 degrees, and is still more preferably from 5 degrees to 20 degrees. 
     In the present exemplary embodiment, as illustrated in  FIG. 2A , the anchor portions  36  are configured by through holes that are also open at upper faces of the anchor bases  38 . Moreover, the opposing face  38 A of each of the anchor bases  38  lies in substantially the same plane as an opposing face  12 C (namely, occlusal surface) of the maxillary piece  12  opposing the mandibular piece  14 . 
     As illustrated in  FIG. 1 , a vertical adjustment member  40  configured, for example, from a resin material is mounted to each of the anchor portions  36 . The vertical adjustment members  40  each includes a protrusion  40 A serving as a mounting portion, and a clamped portion  40 B that extends from one end of the protrusion  40 A in a direction orthogonal to the extension direction of the protrusion  40 A. The other end side of each of the protrusions  40 A fits into the opening portion  36 A of the anchor portion  36 . Note that a retention means such as a hooked portion may be provided at the other end side of the protrusion  40 A to maintain a state fitted into the anchor portion  36 . 
     As illustrated in  FIG. 2B , in a state in which the vertical adjustment member  40  is mounted to the anchor portion  36 , the protrusion  40 A of the vertical adjustment member  40  is provided further to an inner wall face side than a plane E bisecting the vertical adjustment member  40  between the inner wall face side and the outer wall face side. Namely, the vertical adjustment member  40  has an asymmetrical shape with respect to the plane E. The vertical adjustment members  40  each preferably has left-right symmetry with respect to a plane bisecting the protrusion  40 A and the clamped portion  40 B along an extension direction of the protrusion  40 A. 
     The clamped portion  40 B of each of the vertical adjustment members  40  has a substantially rectangular profile and a thickness normally from about 1 mm to about 10 mm. An extension length (namely a width) of the clamped portion  40 B is either substantially the same as a width of the opposing face  12 C of the maxillary piece  12  (namely, a length from the outer wall face  12 A to the inner wall face  12 B), or smaller than the width of the opposing face  12 C. 
     When the protrusion  40 A of each of the vertical adjustment members  40  has been fitted into the opening portion  36 A of the anchor portion  36 , the clamped portion  40 B of the vertical adjustment member  40  is mounted to the opposing face  12 C of the maxillary piece  12 . Thus in a closed mouth state, as illustrated in  FIG. 2A , the clamped portion  40 B of each of the vertical adjustment members  40  is clamped between the opposing face  12 C of the maxillary piece  12  and an opposing face  14 C of the mandibular piece  14  that opposes the maxillary piece  12 . A gap therefore arises between the maxillary piece  12  and the mandibular piece  14 . 
     According to the present exemplary embodiment, by fitting the protrusion  40 A of the vertical adjustment member  40  into the anchor portion  36  of the anchor base  38  formed at the maxillary piece  12 , the vertical adjustment member  40  can easily be anchored to the maxillary piece  12 , while also suppressing the vertical adjustment member  40  from dropping out. Moreover, due to the vertical adjustment member  40  being detachably attached to the anchor portion  36 , the gap between the maxillary piece  12  and the mandibular piece  14  can be appropriately adjusted by replacing the vertical adjustment members  40  with others equipped with clamped portions  40 B of a different thickness. 
     Specifically, for example, by preparing plural vertical adjustment members  40  with different thicknesses of clamped portions  40 B by 1 mm, the gap between the maxillary piece  12  and the mandibular piece  14  can be adjusted by 1 mm by selecting the vertical adjustment member  40  that matches a gap between the upper and lower teeth of a patient. Note that a configuration may be adopted in which a gap is not formed (namely, the thickness is 0 mm) by anchoring vertical adjustment members  40  that only include the protrusions  40 A into the anchor portions  36 . 
     Moreover, the present exemplary embodiment enables the anchor bases  38  to be suppressed from projecting out to the outer wall face  12 A side or the opposing face  12 C side of the maxillary piece  12  due to the anchor bases  38  being formed at the inner wall face  12 B of the maxillary piece  12 . 
     Moreover, in the present exemplary embodiment the anchor bases  38  are formed at the posterior side of the dentition of the maxillary piece  12 . Generally, the width (surface area) of opposing faces  12 C,  12 D is larger at the posterior side of the maxillary piece  12  and the mandibular piece  14  than at the anterior side thereof. Bite closure force from the upper and lower teeth is accordingly more easily applied at the posterior side of the dentition of the maxillary piece  12  and the mandibular piece  14  when the mouth is closed. 
     Thus by forming the anchor bases  38  at the posterior side of the dentition of the maxillary piece  12 , the vertical adjustment members  40  are easily clamped between the maxillary piece  12  and the mandibular piece  14 , enabling dropout of the vertical adjustment members  40  to be suppressed. Moreover, as well as being able to suppress the clamped portion  40 B of each of the vertical adjustment members  40  from projecting to the outer wall face side of the maxillary piece  12  (namely, an outer side of the outer wall face  12 A), obstruction of tongue movement by the vertical adjustment members  40  when the mouth is closed can also be suppressed. 
     In order to provide a given gap between the maxillary piece  12  and the mandibular piece  14  using the vertical adjustment members  40 , the thickness of the clamped portions  40 B, when the clamped portions  40 B are clamped at the posterior side of the dentition, is thinner than the thickness of the clamped portions  40 B, when the clamped portions  40 B are clamped at the anterior side of the dentition. 
     Specifically, for example, a gap of from 4 mm to 5 mm can be disposed at the anterior side of the dentition by clamping clamped portions  40 B having a thickness of 2 mm at the posterior side of the dentition. This enables a reduction in types of vertical adjustment member  40  required (namely, vertical adjustment members  40  having clamped portions  40 B of a different thickness), enabling a reduction in cost. 
     Moreover, in the present exemplary embodiment the vertical adjustment members  40  have asymmetrical shapes with respect to the plane E, and the protrusions  40 A are provided at the inner wall face side of the plane E. The protrusions  40 A can thereby be suppressed from projecting out to the outer wall face side of the maxillary piece  12  (an outer side of the outer wall face  12 A) and from interfering with the coupling members  20  better than configurations in which the protrusions  40 A are provided at the center of the vertical adjustment members  40  or at the outer wall face side thereof. 
     Moreover, the width and shape of the clamped portions  40 B of the vertical adjustment members  40  can be more freely set with respect to a position of the protrusions  40 A than in configurations in which the vertical adjustment members  40  are symmetrically shaped with respect to the plane E. This enables, for example, the clamped portions  40 B to be shaped to match the width and shape of the opposing face  12 C of the maxillary piece  12 , jaw shape, or the like. 
     Moreover, when the mouthpiece  10  is being worn, air (namely, inhaled air and exhaled air) flows between the maxillary piece  12  and the mandibular piece  14  along the center line L each time the patient breaths. Thus in the present exemplary embodiment, the length directions of the opening portions  36 A of the anchor portions  36  formed at the opposing faces  38 A of the anchor bases  38  are not parallel to the center line L, namely, not parallel to the airflow direction. 
     This enables the protrusions  40 A of the vertical adjustment members  40  fitted into the anchor portions  36  to be suppressed from dropping out from the anchor portions  36  due to the airflow better than in configurations in which the length directions of the opening portions  36 A of the anchor portions  36  are parallel to the center line L. 
     Moreover, in the present exemplary embodiment, the pair of anchor bases  38  are provided at the inner wall face  12 B of the maxillary piece  12 , and the gap between the maxillary piece  12  and the mandibular piece  14  is adjusted by the pair of vertical adjustment members  40 . This enables play between the maxillary piece  12  and the mandibular piece  14  to be suppressed better than configurations in which the gap is adjusted using a single vertical adjustment member  40 . 
     Moreover, in the present exemplary embodiment, due to the anchor portions  36  of the anchor bases  38  being configured by through holes that are open at the opposing face  38 A (namely, the lower face) and at the upper face of the anchor bases  38 , cleaning the inside of the anchor portions  36  is easier than configurations in which the anchor portions  36  are configured with bottoms. 
     Second Exemplary Embodiment 
     Next, explanation follows regarding a mouthpiece according to a second exemplary embodiment of the first aspect, with reference to  FIG. 3A  to  FIG. 4B . Note that the same reference numerals are appended to configuration similar to that of the first exemplary embodiment, and explanation thereof will be omitted. 
     As illustrated in  FIG. 3A  and  FIG. 3B , a mouthpiece  50  of the present exemplary embodiment, similarly to the mouthpiece  10  of the first exemplary embodiment, includes a maxillary piece  52  and a mandibular piece  54  coupled together by coupling members  20 . 
     Respective anchor bases  58  including anchor portions  56  are formed so as to project from an inner wall face  52 B at left and right sides (at tooth positions  6  to  7  in the present exemplary embodiment) of the maxillary piece  52  as viewed from a center of dentition. The anchor portions  56  are configured by substantially rectangular shaped indentations, and include elongated opening portions  56 A at inner wall faces  58 A of the anchor bases  58 . 
     As illustrated in  FIG. 4A , when the maxillary piece  52  is viewed from an opposing face  52 C side, imaginary lines M along length directions of the opening portions  56 A (namely, along the inner wall face  58 A of the anchor bases  58 ) extend in directions approaching a center line L of the dentition of the maxillary piece  52  on progression from a posterior side toward an anterior side, and intersect with the center line L. Namely, the length directions of the opening portions  56 A of the anchor portions  56  (the imaginary lines M) are not parallel to the center line L. 
     Furthermore, as illustrated in  FIG. 4B , the imaginary lines M along the length direction of the opening portions  56 A extend in directions approaching an imaginary plane N, that is parallel to an opposing face  52 C of the maxillary piece  52 , on progression from the anterior side toward the posterior side, and intersect with the imaginary plane N. Namely, the length directions of the opening portions  56 A of the anchor portions  56  (the imaginary lines M) are not parallel to the imaginary plane N. 
     Note that the angles of the imaginary lines M illustrated in  FIG. 4A  and  FIG. 4B  are examples thereof. The imaginary lines M may each has any angle to the center line L and to the imaginary plane N as long as they are not parallel thereto. However, angles formed between each of the imaginary lines M and the center line L or the imaginary plane N are preferably from 5 degrees to 45 degrees, are more preferably from 5 degrees to 30 degrees, and are still more preferably from 5 degrees to 20 degrees. 
     As illustrated in  FIG. 3A , vertical adjustment members  60  are mounted to the anchor portions  56 . The vertical adjustment members  60  include L-shaped protrusions  60 A, each serving as a mounting portion and including a horizontal portion  62 A and a vertical portion  62 B, and a clamped portion  60 B that extends from one end of the vertical portion  62 B of the protrusion  60 A in a direction parallel to the extension direction of the horizontal portion  62 A. A retention means such as a hooked portion may be provided at the horizontal portion  62 A of the protrusion  60 A at each of the vertical adjustment members  60  that are fitted into the opening portions  56 A of the anchor portions  56  to maintain the state fitted into the anchor portions  56 . 
     Similarly to the vertical adjustment members  40  of the first exemplary embodiment, as illustrated in  FIG. 4A , in a state in which the vertical adjustment members  60  are mounted to the anchor portions  56 , the protrusions  60 A of the vertical adjustment members  60  are provided at an inner wall face side of a plane F bisecting the vertical adjustment member  60  between the inner wall face side and the outer wall face side. Namely, the vertical adjustment members  60  have an asymmetrical shape with respect to the plane F. 
     When the horizontal portions  62 A of the protrusions  60 A at the vertical adjustment members  60  are fitted into the opening portions  56 A of the anchor portions  56 , the clamped portions  60 B of the vertical adjustment members  60  are mounted to the opposing face  52 C of the maxillary piece  52 . Thus in a closed mouth state, as illustrated in  FIG. 3B , the clamped portions  60 B of the vertical adjustment members  60  are clamped between the opposing face  52 C of the maxillary piece  52  and an opposing face  54 C of the mandibular piece  54 . A gap therefore arises between the maxillary piece  52  and the mandibular piece  54 . 
     According to the present exemplary embodiment, by fitting the horizontal portions  62 A of the protrusions  60 A of the vertical adjustment members  60  into the anchor portions  56  of the anchor bases  58  formed at the maxillary piece  52 , the vertical adjustment members  60  can be easily anchored to the maxillary piece  52 , while also suppressing dropout of the vertical adjustment members  60 . 
     Moreover, when the mouthpiece  50  is being worn, air (namely, inhaled air and exhaled air) flows along the center line L and along the imaginary plane N between the maxillary piece  52  and the mandibular piece  54  each time the patient breaths. Thus in the present exemplary embodiment, the length directions of the opening portions  56 A of the anchor portions  56  formed at the inner wall faces  58 A of the anchor bases  58  are not parallel to the center line L and the imaginary plane N, namely are not parallel to the airflow direction. 
     This enables the protrusions  60 A of the vertical adjustment members  60  fitted to the anchor portions  56  to be better suppressed from dropping out from the anchor portions  56  due to the airflow than in configurations in which the length directions of the opening portions  56 A of the anchor portions  56  are parallel to the center line L and the imaginary plane N. 
     Third Exemplary Embodiment 
     Next, explanation follows regarding a mouthpiece according to a third exemplary embodiment of the first aspect, with reference to  FIG. 5A  and  FIG. 5B . Note that explanation of configuration similar to that of the first exemplary embodiment and the second exemplary embodiment will be omitted. 
     As illustrated in  FIG. 5A , a mouthpiece  70  of the present exemplary embodiment includes a maxillary piece  72  and a mandibular piece  74 . Stoppers  76  that each serves as a positioning member are formed projecting out from an outer wall face  72 A of the maxillary piece  72 . The stoppers  76  are formed integrally with the maxillary piece  72 , and are provided at left and right posterior sides (at tooth positions  6  to  7  in the present exemplary embodiment) of the maxillary piece  72  as viewed from a center of dentition. 
     Wings  78  serving as positioning members are also formed projecting from an outer wall face  74 A of the mandibular piece  74  and extending in a direction toward the maxillary piece  72 . The wings  78  are configured from the same acrylic-based resin as the mandibular piece  74 , and are adjustable in position between tooth positions  6  to  7  of the mandibular piece  74 , that is disposed at an anterior side from the stopper  76 , by use of non-illustrated screws. 
     When the mouthpiece  70  is being worn, as illustrated in  FIG. 5B , movement of the wings  78  toward the posterior side is restricted by side faces of the wings  78  (namely, end faces on the posterior side of the dentition) abutting side faces of the stopper  76  (namely, end faces on the anterior side of the dentition). Namely, the mandibular piece  74  (and hence the mandible) is positioned by the wings  78  and the stoppers  76  so as not to move toward the posterior side with respect to the maxillary piece  72  (and hence the maxilla). 
     Moreover, respective anchor bases  88  are formed so as to project from an inner wall face  72 B of the maxillary piece  72  at left and right sides (at tooth positions  6  to  7  in the present exemplary embodiment) as viewed from the center of dentition. Anchor portions  86  are respectively formed at the anchor bases  88 . Note that the anchor portions  86  are configured by female threaded holes that open at lower faces of the anchor bases  88 , namely opposing faces  88 A opposing the mandibular piece  74 . The opposing faces  88 A of the anchor bases  88  are configured so as to lie in substantially the same plane as an opposing face  72 C (namely the occlusal surface) of the maxillary piece  72 . 
     As illustrated in  FIG. 5A , vertical adjustment members  90  are mounted to the anchor bases  88 . The vertical adjustment members  90  each includes a substantially rectangular shaped clamped portion  90 B and a through hole  90 A serving as a mounting portion and formed so as to penetrate through the clamped portion  90 B. The vertical adjustment members  90  are fixed to the anchor bases  88  by screwing screws  92  that have been inserted through the through holes  90 A into the anchor portions  86  of the anchor bases  88 . 
     In a mounted state of the vertical adjustment members  90  to the anchor portions  86 , the through holes  90 A in the vertical adjustment members  90  are provided at an inner wall face side of a plane G bisecting the vertical adjustment member  90  between the inner wall face side and an outer wall face side. Namely, the vertical adjustment members  90  have asymmetrical shapes with respect to the plane G. Note that the vertical adjustment members  90  each preferably has left-right symmetry with respect to a plane bisecting the through hole  90 A and the clamped portion  90 B along an axial line of the through hole  90 A. 
     The clamped portions  90 B of the vertical adjustment members  90  are mounted to the opposing face  72 C of the maxillary piece  72  when the vertical adjustment members  90  are fixed to the anchor bases  88 . Thus in a closed mouth state, as illustrated in  FIG. 5B , the clamped portions  90 B of the vertical adjustment members  90  are clamped between the opposing face  72 C of the maxillary piece  72  and an opposing face  74 C of the mandibular piece  74 . A gap therefore arises between the maxillary piece  72  and the mandibular piece  74 . 
     In the present exemplary embodiment, the screws  92 , that have been inserted through the through holes  90 A of the vertical adjustment members  90 , are screwed into the anchor portions  86  of the anchor bases  88  formed at the maxillary piece  72 , whereby the vertical adjustment members  90  can be easily anchored to the maxillary piece  72 , while also suppressing the vertical adjustment members  90  from dropping out. 
     Other Exemplary Embodiments 
     The first aspect is not limited to the exemplary embodiments described above, and various other exemplary embodiments are possible within the scope of the present disclosure. Moreover, appropriate combinations may be made from the above first to third exemplary embodiments. 
     For example, whereas in the first to third exemplary embodiments, the anchor bases  38 ,  58 ,  88  were formed projecting out from the inner wall face  12 B,  52 B,  72 B of the maxillary piece  12 ,  52 ,  72 , the anchor bases  38 ,  58 ,  88  do not necessarily project out from the inner wall face  12 B,  52 B,  72 B of the maxillary piece  12 ,  52 ,  72 . 
     Moreover, the anchor bases  38 ,  58 ,  88  preferably do not project below the opposing face  12 C,  52 C,  72 C of the maxillary piece  12 ,  52 ,  72 . This enables obstruction of tongue movement by the anchor bases  38 ,  58 ,  88  to be suppressed. Furthermore, the anchor bases  38 ,  58 ,  88  may be formed at the inner wall face  14 B,  54 B,  74 B of the mandibular piece  14 ,  54 ,  74 , and may be formed at both the maxillary piece  12 ,  52 ,  72  and the mandibular piece  14 ,  54 ,  74 . 
     Furthermore, the mounting portion configurations of the anchor portion  36 ,  56 ,  86  at the anchor bases  38 ,  58 ,  88  and the vertical adjustment members  40 ,  60 ,  90  are not limited to that of the above exemplary embodiments. For example, the anchor portions  56 ,  86  may be configured as through holes in the second and third exemplary embodiment, similarly to as in the first exemplary embodiment, and the anchor portions  36 ,  56  may be configured by female threaded holes in the first and second exemplary embodiments, similarly to as in the third exemplary embodiment. 
     Moreover, a rail groove serving as an anchor portion may be formed at the anchor bases  38 ,  58 ,  88 , and a rail serving as a mounting portion to fit into the rail groove may be formed at the vertical adjustment members  40 ,  60 ,  90 . Furthermore, a protrusion serving as an anchor portion may be formed at the anchor bases  38 ,  58 ,  88 , and an indentation serving as a mounting portion into which the protrusion fits may be formed at the vertical adjustment members  40 ,  60 ,  90 . 
     In addition, the vertical adjustment members  40 ,  60 ,  90  may be mounted to the anchor bases  38 ,  58 ,  88  by various methods, such as methods for anchoring using fastenings configured by a male member provided to one thereof and a female member configured to the other thereof. 
     Moreover, although in the first to third exemplary embodiments the gap between the maxillary piece  12 ,  52 ,  72  and the mandibular piece  14 ,  54 ,  74  is adjusted by the pair of vertical adjustment members  40 ,  60 ,  90 , the number and position of the vertical adjustment members  40 ,  60 ,  90  (and the anchor bases  38 ,  58 ,  88 ) are not limited to those of the above exemplary embodiments. 
     Furthermore, the shape of the vertical adjustment members  40 ,  60 ,  90  may also be any shape. For example, asymmetries in jaw shape of the patient are correctable using the vertical adjustment members  40 ,  60 ,  90  by setting non-uniform thicknesses for the clamped portions  40 B,  60 B,  90 B, or by using clamped portions  40 B,  60 B,  90 B of different thicknesses in the pair of vertical adjustment members  40 ,  60 ,  90 . 
     Moreover, in the second exemplary embodiment, the imaginary lines M along the length directions of the opening portions  56 A of the anchor portions  56  are each not parallel to both the center line L and the imaginary plane N. However, the protrusions  60 A of the vertical adjustment members  60  fitted into the anchor portions  56  can be suppressed from dropping out of the anchor portions  56  due to the airflow as long as the imaginary lines M are each set so as not to be parallel to at least one of the center line L or the imaginary plane N. 
     Moreover, although the mouthpiece  10 ,  50  is a push-type mouthpiece in the first and second exemplary embodiments, a pull-type configuration may be adopted in which the mandibular piece  14 ,  54  (mandible) is pulled forward by the coupling members  20 , by setting the upper attachment portions  16  at the anterior side of the dentition from (at the front teeth side of) the lower attachment portions  18 . Furthermore, the configuration of the coupling members  20  is also not limited to those of the exemplary embodiments described above, and any configuration may be adopted that is a configuration coupling the maxillary piece  12  and the mandibular piece  14  together so as to be capable of adjusting the length of the coupling portion. 
     Moreover, although in the third exemplary embodiment the stoppers  76  are formed at the maxillary piece  72  and the wings  78  are formed at the mandibular piece  74 , the wings  78  may be formed at the maxillary piece  72  and the stoppers  76  formed at the mandibular piece  74 . 
     Furthermore, the materials to configure the maxillary piece  12  and the mandibular piece  14 , the upper attachment portions  16 , the lower attachment portions  18 , and the coupling members  20  are not limited to the examples of materials given in the first exemplary embodiment. For example, although the upper attachment portion  16 , the lower attachment portion  18 , and the coupling members  20  are made of metal therein, they may be configured from a plastic from the perspectives of enabling application to patients with metal allergies, achieving a saving in weight, while also retaining the strength of members, or reducing any feeling of discomfort inside the oral cavity. 
     Second Aspect 
     A mouthpiece according to a second aspect of the present disclosure includes a maxillary piece that is mounted to maxillary dentition, a mandibular piece that is mounted to mandibular dentition, a positioning member that positions the mandibular piece with respect to the maxillary piece, an anchor portion that includes a mount formed at at least one location or more at an outer periphery of at least one of the maxillary piece or the mandibular piece, or at an opposing face of the maxillary piece or the mandibular piece where they oppose each other, and a vertical adjustment member that is mounted to the mount of the anchor portion and is clamped between the maxillary piece and the mandibular piece. 
     In the second aspect, the mount of the anchor portion is formed at at least one location or more at the outer periphery of the maxillary piece or the mandibular piece or at the opposing face. There is accordingly a lower risk of being swallowed by the patient even if the vertical adjustment member were to drop out than configurations in which the mount is formed at an inner wall face side of the maxillary piece or the mandibular piece. This enables the vertical adjustment member to be made more compact, as the vertical adjustment member does not need to be enlarged. 
     Note that in the following second aspect, configuration referred to as “a projection” in the disclosure of Japanese Patent Application No. 2016-127904 is referred to as “an anchor base” herein, and configuration referred to as “a thick portion” therein is referred to as “a clamped portion” herein. 
     First Exemplary Embodiment 
     Explanation follows regarding a mouthpiece according to a first exemplary embodiment of the second aspect, with reference to  FIG. 6A  and  FIG. 6B . 
     Similarly to the mouthpiece  10  of the first aspect, a mouthpiece  110  of the present exemplary embodiment is employed for sleep apnea syndrome. As illustrated in  FIG. 6A  and  FIG. 6B , the mouthpiece  110  includes a maxillary piece  112  worn at maxillary dentition, and a mandibular piece  114  worn at mandibular dentition. 
     The maxillary piece  112  and the mandibular piece  114  are, for example, configured from an acrylic-based resin having a modulus of elasticity of approximately 2150 MPa in bending tests according to JIS T6501. Examples of materials for the maxillary piece  112  and the mandibular piece  114  also include polyester-based resins, polycarbonate-based resins, urethane-based resins, vinyl acetate-based resins, polyamide-based resins, and the like. 
     Metal upper attachment portions  116  are provided projecting from an outer wall face  112 A of the maxillary piece  112 , so as to project out from the outer wall face  112 A at left and right posterior sides of a dentition (at tooth positions  6  to  7  in the present exemplary embodiment) as viewed from a center of the dentition. Metal lower attachment portions  118  are provided at an outer wall face  114 A of the mandibular piece  114 , so as to project out from the outer wall face  114 A at left and right posterior sides of a dentition (at tooth positions  3 - 4  in the present exemplary embodiment) as viewed from the center of the dentition. 
     Moreover, the right upper attachment portion  116  and the right lower attachment portion  118 , and the left upper attachment portion  116  and the left lower attachment portion  118 , are respectively coupled together by metal coupling members  120  capable of pivoting. The coupling members  120  are positioning members to position such that the mandibular piece  114  does not move toward a posterior side with respect to the maxillary piece  112 . The maxillary piece  112  and the mandibular piece  114  are coupled together by the pair of coupling members  120  so as to be capable of opening and closing. 
     In the mouthpiece  110  of the present exemplary embodiment, the upper attachment portion  116  is positioned at a posterior side from (namely, at the back teeth side of) the lower attachment portion  118  as viewed from the center of the dentition. Namely, the mouthpiece  110  is configured as a push-type mouthpiece that, when being worn, pushes the mandibular piece  114  (and hence the mandible) forward using the coupling members  120 . 
     The coupling members  120  each includes a length adjustment mechanism  122 , a sliding mechanism  124 , and eyelets  126  attached to the upper attachment portion  116  and the lower attachment portion  118 . The length adjustment mechanisms  122  each includes a nut  128  and a male screw  130  screwed into the nut  128 . A screw amount of the male screws  130  is adjusted by rotating the nuts  128  to adjust the length of the coupling members  120  in a continuous manner. 
     The sliding mechanisms  124  each include a sleeve  132  and a rod  134 . The coupling members  120  are able to follow the maxillary piece  112  and the mandibular piece  114  by the rods  134  sliding inside the sleeves  132  to match the movement of the maxillary piece  112  and the mandibular piece  114 . A distance between the upper attachment portion  116  and the lower attachment portion  118  (a distance between respective centers) is adjusted by the coupling members  120  so as to be between about 18 mm and about 50 mm. 
     Anchor portions  138  are formed at an outer wall face  112 A of the maxillary piece  112  at left and right sides (at tooth positions  4 - 5  in the present exemplary embodiment) as viewed from the center of the dentition. The anchor portions  138  each is formed as a substantially rectangular shaped through hole penetrating through to an inner wall face of the maxillary piece  112  from the outer wall face  112 A thereof. Open ends at the outer wall face  112 A side of the anchor portions  138  are configured as mounts  138 A to which vertical adjustment members  136  are mounted. 
     The vertical adjustment members  136  are configured, for example, from a resin material, and include protrusions  136 A that fit into the mounts  138 A of the anchor portions  138 , and clamped portions  136 B that extend in a horizontal direction along extension directions of the protrusions  136 A. Hooked portions  137  are formed at leading ends of the protrusions  136 A. Note that the vertical adjustment members  136  have left-right symmetry with respect to a plane R bisecting each of the protrusions  136 A along the extension direction of the protrusions  136 A. 
     The clamped portions  136 B each has a substantially rectangular profile and a thickness from about 1 mm to about  10  mm. An extension length (namely a width) of the clamped portions  136 B is either substantially the same as a width of an opposing face  112 B of the maxillary piece  112  that opposes the mandibular piece  114  (namely, a length from the outer wall face  112 A to the inner wall face), or smaller than the width of the opposing face  112 B. 
     When the protrusions  136 A of the vertical adjustment members  136  are fitted into the mounts  138 A of the anchor portions  138 , the hooked portions  137  at the leading ends of the protrusions  136 A are anchored inside the anchor portions  138  or at the inner wall face of the maxillary piece  112 , preventing removal of the vertical adjustment members  136  from the anchor portions  138 . Moreover, as illustrated in  FIG. 6B , the clamped portions  136 B of the vertical adjustment members  136  are mounted to the opposing face  112 B of the maxillary piece  112 . 
     Thus in a closed mouth state, the clamped portions  136 B of the vertical adjustment members  136  are clamped between the opposing face  112 B of the maxillary piece  112  and an opposing face  114 B of the mandibular piece  114  opposing the maxillary piece  112 . A gap therefore arises between the maxillary piece  112  and the mandibular piece  114 . 
     According to the present exemplary embodiment, the protrusions  136 A at the vertical adjustment members  136  fit into the anchor portions  138  of the maxillary piece  112 , enabling the vertical adjustment members  136  to be easily anchored to the maxillary piece  112 . Moreover, due to the vertical adjustment members  136  being detachably attached to the anchor portions  138  of the maxillary piece  112 , the gap between the maxillary piece  112  and the mandibular piece  114  can be appropriately adjusted by replacing the vertical adjustment members  136  with others equipped with clamped portions  136 B of a different thickness. 
     Specifically, by preparing plural vertical adjustment member  136  with different thicknesses of clamped portion  136 B by 1 mm, the gap between the maxillary piece  112  and the mandibular piece  114  can be adjusted by 1 mm by selecting the vertical adjustment member  136  that matches a gap between the upper and lower teeth of a patient. Note that a configuration may be adopted in which a gap is not formed (namely, the thickness is 0 mm) by anchoring vertical adjustment members  136  that only include the protrusions  136 A into the anchor portions  138 . 
     Moreover, in the present exemplary embodiment there are two anchor portions  138  formed at the outer wall face  112 A of the maxillary piece  112 , and the gap between the maxillary piece  112  and the mandibular piece  114  is adjusted by the pair of vertical adjustment members  136 . This enables play between the maxillary piece  112  and the mandibular piece  114  to be suppressed better than configurations in which the gap is adjusted using a single vertical adjustment member  136 . 
     Moreover, in the present exemplary embodiment, the mounts  138 A of the anchor portions  138  are each formed at the outer wall face  112 A of the maxillary piece  112 , namely, at outer sides of a line J passing through a width direction center of the opposing face  112 B of the maxillary piece  112 . 
     There is accordingly a lower risk of being swallowed by the patient even if the vertical adjustment members  136  were to drop out than configurations in which the mounts  138 A are formed at the inner wall face of the maxillary piece  112 . Furthermore, when the mouthpiece  110  is mounted, the vertical adjustment members  136  are sandwiched between the maxillary piece  112  and a cheek of the patient, enabling dropout of the vertical adjustment members  136  to be suppressed. 
     Moreover, in the present exemplary embodiment the anchor portions  138  are configured by through holes that pierce through from the outer wall face  112 A of the maxillary piece  112  to the inner wall face thereof. Cleaning the anchor portions  138  is accordingly easier than configurations in which the anchor portions  138  are bottomed. Furthermore, hooked portions  137  are formed at the leading ends of the protrusions  136 A at the vertical adjustment members  136 , enabling the vertical adjustment members  136  to be suppressed from dropping out from the anchor portions  138 . 
     Moreover, in the present exemplary embodiments, the vertical adjustment members  136  have left-right symmetry, enabling common vertical adjustment members  136  to be employed for anchoring to the anchor portions  138  at both the left and right sides of the maxillary piece  112 . Note that, when necessary, fine adjustments to the shape of the vertical adjustment members  136  are possible by separate machining of the vertical adjustment members  136 . 
     Second Exemplary Embodiment 
     Explanation follows regarding a mouthpiece according to a second exemplary embodiment of the second aspect, with reference to  FIG. 7A  and  FIG. 7B . Note that explanation will be omitted of configuration similar to that of the first exemplary embodiment. 
     As illustrated in  FIG. 7A  and  FIG. 7B , in a mouthpiece  140  of the present exemplary embodiment, an anchor base  157  is formed at an outer wall face  144 A at a center of a dentition (namely tooth position  1 ) of a mandibular piece  144  such that the anchor base  157  is projected further outer side than other portions of the outer wall face  144 A. Note that the upper face of the anchor base  157  preferably does not project above an opposing face  144 B of the mandibular piece  144 , and more preferably lies in substantially the same plane as the opposing face  144 B of the mandibular piece  144 . 
     Moreover, an anchor portion  158  is formed at an upper face of the anchor base  157 . The anchor portion  158  is a substantially rectangular shaped through hole piercing through from the upper face to a lower face of the anchor base  157 . An open end of the anchor portion  158  at an upper face side of the anchor base  157  configures a mount  158 A into which a vertical adjustment member  156  is mounted. 
     The vertical adjustment member  156  includes a protrusion  156 A that fits into the mount  158 A of the anchor portion  158 , and a clamped portion  156 B that extends in a direction orthogonal to an extension direction of the protrusion  156 A. An extension direction length of the protrusion  156 A of the vertical adjustment member  156  is shorter than a depth of the anchor portion  158  (namely, than a length from the upper face to the lower face of the anchor base  157 ). The vertical adjustment member  156  also has left-right symmetry with respect to a plane S bisecting the protrusion  156 A along the extension direction of the protrusion  156 A. 
     When the protrusion  156 A of the vertical adjustment members  156  is fitted into the mount  158 A of the anchor portion  158 , as illustrated in  FIG. 7B , the clamped portion  156 B of the vertical adjustment member  156  is mounted to the opposing face  144 B of the mandibular piece  144 . Thus, in a closed mouth state, the clamped portion  156 B of the vertical adjustment member  156  is clamped between an opposing face  142 B of a maxillary piece  142  and the opposing face  144 B of the mandibular piece  144 . A gap therefore arises between the maxillary piece  142  and the mandibular piece  144 . 
     In the present exemplary embodiment, similarly to in the first exemplary embodiment, the gap between the maxillary piece  142  and the mandibular piece  144  can be appropriately adjusted by replacing the vertical adjustment member  156  anchored at the anchor portion  158  of the mandibular piece  144  with another vertical adjustment member  156  equipped with a clamped portion  156 B of a different thickness. 
     Moreover, according to the present exemplary embodiment, the anchor portion  158  is provided at the anchor base  157  formed at the outer wall face  144 A of the mandibular piece  144 . Moreover, the extension direction length of the protrusion  156 A of the vertical adjustment member  156  is shorter than the depth of the anchor portion  158 . This enables the protrusion  156 A of the vertical adjustment member  156  to be prevented from interfering with the dentition when the vertical adjustment member  156  has been fitted into the anchor portion  158 . 
     Note that the anchor portion  158  is formed at an outer side of a line P passing through a width direction center of the opposing face  144 B of the mandibular piece  144 . There is accordingly a lower risk of being swallowed by the patient even if the vertical adjustment member  156  were to dropout than configurations in which the anchor portion  158  was formed at an inner side of the line P passing through the center. 
     Moreover, in the present exemplary embodiment the anchor portion  158  is formed in a direction orthogonal to the opposing face  144 B of the mandibular piece  144 . The risk of the protrusion  156 A of the vertical adjustment member  156  being removed from the anchor portion  158  of the mandibular piece  144  is accordingly lower than in configurations in which the anchor portion  158  is formed in a horizontal direction to the opposing face  144 B of the mandibular piece  144 , even in cases in which force is applied to the opposing face  144 B in a horizontal direction (namely, a direction parallel to the opposing face  144 B) by bruxism or the like. 
     Moreover, the gap between the maxillary piece  142  and the mandibular piece  144  is adjusted by the single vertical adjustment member  156 . This enables the number of components to be reduced compared to configurations in which adjustment is made using plural vertical adjustment members  156 . 
     Third Exemplary Embodiment 
     Next, explanation follows regarding a mouthpiece according to a third exemplary embodiment of the second aspect, with reference to  FIG. 8A  and  FIG. 8B . Note that explanation will be omitted of configuration similar to that of the first exemplary embodiment and the second exemplary embodiment. 
     As illustrated in  FIG. 8A  and  FIG. 8B , in a mouthpiece  160  of the present exemplary embodiment, stopper portions  166  serving as positioning members are formed projecting from an outer wall face  162 A of a maxillary piece  162 . The stopper portions  166  are formed integrally with the maxillary piece  162 , and are provided at left and right posterior sides of a dentition (at tooth positions  6  to  7  in the present exemplary embodiment) of the maxillary piece  162  as viewed from a center of the dentition. 
     Wing portions  168  serving as positioning members are also formed projecting from an outer wall face  164 A of a mandibular piece  164  and extending toward the maxillary piece  162 . The wing portions  168  are configured from the same acrylic-based resin as the mandibular piece  164 , and, by use of screws  177 , are adjustable in position between tooth positions  6  to  7  of the mandibular piece  164 , which is an anterior side from the stopper portions  166 . 
     When the mouthpiece  160  is being worn, the wing portions  168  is restricted from moving toward a posterior side by side faces (namely, end faces at the posterior side of the dentition) of the wing portions  168  abutting side faces (namely, end faces at the anterior side of the dentition) of the stopper portions  166 . Namely, the mandibular piece  164  (and hence the mandible) is positioned by the wing portions  168  and the stopper portions  166  so that the mandibular piece  164  does not move toward the posterior side with respect to the maxillary piece  162  (and hence the maxilla). 
     Moreover, anchor portions  178  are formed at lower faces  166 A of the stopper portions  166  that oppose the mandibular piece  164 . The anchor portions  178  are substantially rectangular shaped through holes penetrating through the stopper portions  166  from a lower face  166 A to an upper face thereof. Open ends of the anchor portions  178  at a lower face  166 A side of the stopper portions  166  configure mounts  178 A into which vertical adjustment members  176  are mounted. 
     The vertical adjustment members  176  include protrusions  176 A that fit into the mounts  178 A of the anchor portions  178 , and clamped portions  176 B that extend in a direction orthogonal to an extension direction of the protrusions  176 A. An extension direction length of the protrusions  176 A of the vertical adjustment members  176  is shorter than a depth of the anchor portions  178  (namely, a length from the lower face  166 A to the upper face of the stopper portions  166 ). The vertical adjustment members  176  each has left-right symmetry with respect to a plane T bisecting the protrusion  176 A along the extension direction of the protrusion  176 A. 
     When the protrusions  176 A of the vertical adjustment members  176  are fitted into the mounts  178 A of the anchor portions  178 , as illustrated in  FIG. 8B , the clamped portions  176 B of the vertical adjustment members  176  are mounted to the lower face  166 A of the stopper portions  166  and an opposing face  162 B of the maxillary piece  162 . Thus in a closed mouth state, the clamped portions  176 B of the vertical adjustment members  176  are clamped between the opposing face  162 B of the maxillary piece  162  and the opposing face  164 B of the mandibular piece  164 . A gap therefore arises between the maxillary piece  162  and the mandibular piece  164 . 
     Note that in this situation, end faces at an anterior side of the dentition of the clamped portions  176 B of the vertical adjustment members  176 , together with the stopper portions  166 , abut side faces (namely, end faces at a posterior side of the dentition) of the wing portions  168 , restricting the wing portions  168  from moving toward the posterior side. 
     The present exemplary embodiment, similarly to the first exemplary embodiment and the second exemplary embodiment, enables the gap between the maxillary piece  162  and the mandibular piece  164  to be appropriately adjusted by replacing the vertical adjustment members  176  anchored to the anchor portions  178  of the stopper portions  166  with other vertical adjustment members  176  equipped with clamped portions  176 B of a different thickness. 
     Moreover, in the present exemplary embodiment, due to forming the anchor portions  178  at the lower faces  166 A of the stopper portions  166 , the stopper portions  166  can be utilized as anchor portions for the vertical adjustment members  176 . This enables the thickness and width of the maxillary piece  162  to be thinner than in configurations in which the anchor portions  178  are formed at the outer wall face  162 A and the opposing face  162 B of the maxillary piece  162 , since additional space to form the anchor portions  178  is no longer required. 
     Other Exemplary Embodiments 
     Note that the second aspect is not limited to the exemplary embodiments described above, and various other exemplary embodiments are possible within the scope of the present disclosure. Moreover, appropriate combinations may be made from the above first to third exemplary embodiments. For example, although the anchor portions  138  are configured by through holes in the first exemplary embodiment, the anchor portions  138  may be configured by bottomed indentations instead of through holes. 
     Moreover, as illustrated in  FIG. 9A , rail grooves  184  serving as anchor portions may be formed at outer wall face  182 A of a maxillary piece  182 , and the vertical adjustment members  186  are anchored to the maxillary piece  182  by fitting rails  186 A provided at upper faces of clamped portions  186 B of vertical adjustment members  186  into the rail grooves  184 . 
     In such cases, the vertical adjustment members  186  can be better suppressed from projecting out from the outer wall face  182 A of the maxillary piece  182  than in the mouthpiece  110  of the first exemplary embodiment. Moreover, as illustrated in  FIG. 9B , protrusions  190  serving as anchor portions may be formed at an outer wall face  188 A of a maxillary piece  188 , and the protrusions  190  of the maxillary piece  188  fitted into indentations  192 A provided at vertical adjustment members  192 . 
     Similarly, in the second exemplary embodiment, the anchor portion  158  is formed at the opposing face  144 B of the mandibular piece  144  (namely, at the upper face of the anchor base  157 ), and the protrusion  156 A provided at the vertical adjustment member  156  fitted therein. However, as illustrated in  FIG. 9C , protrusions  196  serving as anchor portions may be formed at an opposing face  194 B of a maxillary piece  194 , and the protrusions  196  of the maxillary piece  194  fitted into indentations  198 A provided at vertical adjustment members  198 . 
     In addition, the vertical adjustment members  136  may be anchored to the maxillary piece  112  and the mandibular piece  114  by various methods, such as methods for using fastenings configured by a male member provided at one thereof and a female member configured at the other thereof, methods for using screw mechanisms configured by a male threaded portion provided at one thereof and a female threaded portion provided at the other thereof, or the like. 
     Moreover, although in the first exemplary embodiment the gap between the maxillary piece  112  and the mandibular piece  114  is adjusted using the pair of vertical adjustment members  136 , a configuration may be adopted in which the vertical adjustment members  136  are coupled together as a single member, or are coupled together and integrated into a single unit. 
     Moreover, the vertical adjustment members  136  may have any shape as long as they have a configuration enabling the gap between the maxillary piece  112  and the mandibular piece  114  to be adjusted. Furthermore, the number and anchor positions of the vertical adjustment members  136  are not limited to those of the exemplary embodiment described above, and a configuration may be adopted in which three or more of the vertical adjustment members  136  are anchored to the maxillary piece  112  and the mandibular piece  114 . 
     Moreover, in the third exemplary embodiment the anchor portions  178 , to which the vertical adjustment members  176  are anchored, are formed at the stopper portions  166  serving as positioning members. However, the stopper portions  166  may themselves configure anchor portions, and a configuration may be adopted in which the vertical adjustment members  176  are directly anchored to the stopper portions  166 . 
     Similarly, in the first and third exemplary embodiments, the coupling members  120  may themselves serve as positioning members, and the wing portions  168  may themselves serve as anchor portions. Specifically, for example, a configuration may be adopted in which the vertical adjustment members  136 ,  176  are directly anchored to the coupling members  120  and the wing portions  168  by providing through holes in the vertical adjustment members  136 ,  176 , and inserting the coupling members  120  and the wing portions  168  through the through holes. 
     Moreover, in the first exemplary embodiment, the mounts  138 A to which the vertical adjustment members  136  are mounted are configured only at open ends at the outer wall face  112 A side of the maxillary piece  112 . However, the mounts  138 A to which the vertical adjustment members  136  are mounted may be formed at both the open ends on the outer wall face  112 A side and open ends on an inner wall face side (not illustrated in the drawings). 
     Specifically, a configuration may be adopted in which a pair of protrusions  136 A are formed at each of the vertical adjustment members  136 , and each of the pairs of protrusions  136 A are respectively fitted into the mounts  138 A on the outer wall face  112 A side and the inner wall face side of the maxillary piece  112 . 
     Moreover, although the mouthpiece  110 ,  140  is a push-type mouthpiece in the first and second exemplary embodiments, a pull-type configuration may be adopted in which the mandibular piece  114 ,  144  (and hence the mandible) is pulled forward by the coupling members  120 ,  150  by setting the upper attachment portions  116 ,  146  at the anterior side (namely, at a front teeth side) from the lower attachment portions  118 ,  148 . 
     Moreover, although in the third exemplary embodiment the stopper portions  166  are formed at the maxillary piece  162 , and the wing portions  168  are formed at the mandibular piece  164 , the wing portions  168  may be formed at the maxillary piece  162  and the stopper portions  166  may be formed at the mandibular piece  164 . 
     Moreover, although the end faces on the anterior side of the clamped portions  176 B of the vertical adjustment members  176  are positioned to abut the side faces (namely, the end faces at the posterior side) of the wing portions  168 , they may be positioned so as not to abut the side faces (namely, end faces at the posterior side) of the wing portions  168 . Furthermore, similarly to in the first aspect, the maxillary piece  112  and the mandibular piece  114 , and the upper attachment portion  116 , the lower attachment portion  118 , and the coupling members  120  may be configured from a plastic. 
     Third Aspect 
     A mouthpiece according to a third aspect of the present disclosure includes a maxillary piece that is mounted to maxillary dentition, a mandibular piece that is mounted to mandibular dentition, a wing portion that is provided at an outer wall face of one of the maxillary piece or the mandibular piece and that extends in a direction toward the other of the maxillary piece or the mandibular piece, a stopper portion that is provided at an outer wall face of the other of the maxillary piece or the mandibular piece, and that restricts movement to a posterior side of dentition of the mandibular piece by abutting the wing portion, and a relative position adjustment member that is provided at the wing portion or the stopper portion to adjust a relative position of the maxillary piece and the mandibular piece. 
     In the third aspect, the wing portion or the stopper portion, that is provided with the relative position adjustment member, is strongly fixed to the maxillary piece or the mandibular piece. This enables the size of the relative position adjustment member itself to be made smaller, as well as enabling dropout of the relative position adjustment member to be suppressed. 
     “A relative position adjustment member” referred to herein is a member to adjust at least one of a relative position of the maxillary and mandibular pieces in an anterior-posterior direction or a relative position (i.e. gap) between the maxillary and mandibular pieces in a vertical direction, and encompasses “a vertical adjustment member” of the first aspect and the second aspect. 
     Note that in the following third aspect, configuration referred to as “a relative position adjustment portion” in the disclosure of Japanese Patent Application No. 2016-127905 is referred to as “a relative position adjustment member” herein, and configuration referred to as “a thick portion” therein is referred to as “a clamped portion” herein. 
     First Exemplary Embodiment 
     Explanation follows regarding a mouthpiece according to a first exemplary embodiment of the third aspect, with reference to  FIG. 10A  to  FIG. 10B . 
     Similarly to in the first aspect and the second aspect, a mouthpiece  210  of the present exemplary embodiment is a mouthpiece employed for sleep apnea syndrome. As illustrated in  FIG. 10A  and  FIG. 10B , the mouthpiece  210  includes a maxillary piece  212  worn at maxillary dentition, and a mandibular piece  214  worn at mandibular dentition. Note that the maxillary piece  212  and the mandibular piece  214  are, for example, configured from an acrylic-based resin having a modulus of elasticity of approximately 2150 MPa in bending tests according to JIS T6501. 
     Stopper portions  216  are formed projecting out from an outer wall face  212 A of the maxillary piece  212 . The stopper portions  216  are, for example, configured from the same acrylic-based resin as the maxillary piece  212 , and are provided at left and right posterior sides (at tooth positions  6  to  7  in the present exemplary embodiment) of the maxillary piece  212  as viewed from a center of dentition. 
     Wing attachment portions  220  to which wing portions  224  are attached are formed at an outer wall face  214 A of the mandibular piece  214 . The wing attachment portions  220  are adjustable in position between tooth positions  6  to  7  of the mandibular piece  214 , which is an anterior side from the stopper portions  216 , by use of screws  222 . 
     Moreover, upper faces of the wing attachment portions  220  (namely, faces opposing the maxillary piece  212 ) configure attachment faces  220 A for wing portions  224 , and projections  218  that project toward the maxillary piece  212  are provided at the attachment faces  220 A. Note that the attachment faces  220 A lie in substantially the same plane as an opposing face  214 B of the mandibular piece  214 . 
     The wing portions  224  are, for example, configured from the same acrylic-based resin as the mandibular piece  214 . Moreover, the wing portions  224  each includes a wing  224 A extending toward the maxillary piece  212 , and a relative position adjustment member  224 B that extends from a lower end of the wing  224 A in a direction orthogonal to the extension direction of the wing  224 A. 
     The relative position adjustment members  224 B have substantially rectangular shapes and a thickness of from about 1 mm to about 10 mm. The extension length (namely, a width) of the relative position adjustment members  224 B is substantially the same as a width (namely, a length from the outer wall face  214 A to an inner wall face) of the opposing face  214 B of the mandibular piece  214  opposing the maxillary piece  212 , or smaller than the width of the opposing face  214 B. 
     Moreover, attachment grooves  226  are formed at lower faces of the wing  224 A (namely, faces opposing the mandibular piece  214 ). As illustrated in  FIG. 10B , the wing portions  224  are detachably attached to the upper faces of the wing attachment portions  220  by the projections  218  with curved leading end portions fitting into the attachment grooves  226 . Note that a configuration may be adopted in which a retention means such as hooked portions are provided at the projections  218  to maintain the fitted state thereof in the attachment grooves  226 . 
     When the wing portions  224  are attached to the wing attachment portions  220 , the relative position adjustment members  224 B of the wing portions  224  are mounted to the opposing face  214 B of the mandibular piece  214 . Thus in a closed mouth state, the relative position adjustment members  224 B are clamped between an opposing face  212 B of the maxillary piece  212 , opposing the mandibular piece  214 , and the opposing face  214 B of the mandibular piece  214 . A gap therefore arises between the maxillary piece  212  and the mandibular piece  214 . 
     Note that when the mouthpiece  210  is being worn, movement to a posterior side of the wing portions  224  is restricted by side faces (namely, end faces at a posterior side) of the wing portions  224  abutting side faces (namely, end faces at an anterior side) of the stopper portions  216 . Namely, the mandibular piece  214  (and hence the mandible) is positioned by the wing portions  224  and the stopper portions  216  so that the mandibular piece  214  does not move to the posterior side with respect to the maxillary piece  212  (and hence the maxilla). 
     According to the present exemplary embodiment, the relative position adjustment members  224 B are clamped between the maxillary piece  212  and the mandibular piece  214  thereby a gap being formed therebetween by the wing portions  224  that is formed integrally with the relative position adjustment members  224 B and that is attached to the wing attachment portions  220  of the mandibular piece  214 . 
     In such a configuration, the wing portions  224  are detachably attached to the wing attachment portions  220 . This therefore enables the gap between the maxillary piece  212  and the mandibular piece  214  to be appropriately adjusted by replacing the wing portions  224  with others equipped with relative position adjustment members  224 B of a different thickness. 
     Specifically, for example, the gap between the maxillary piece  212  and the mandibular piece  214  can be adjusted by 1 mm by preparing plural wing portions  224  equipped with relative position adjustment members  224 B of different thicknesses by 1 mm, and then selecting a wing portions  224  that matches a gap between the upper and lower teeth of a patient. 
     Moreover, in the present exemplary embodiment, the wing portions  224  are respectively attached to the pair of wing attachment portions  220 . Namely, the gap between the maxillary piece  212  and the mandibular piece  214  is adjusted by the pair of relative position adjustment members  224 B. This means that play between the maxillary piece  212  and the mandibular piece  214  can be suppressed better than configurations in which the gap between the maxillary piece  212  and the mandibular piece  214  is adjusted using a single relative position adjustment member  224 B. 
     Moreover, according to the present exemplary embodiment, the relative position adjustment members  224 B are provided at the wing portions  224 . This enables the thicknesses and widths of the maxillary piece  212  and the mandibular piece  214  to be thinner than in configurations in which the relative position adjustment members  224 B are attached to an outer wall faces  212 A,  214 A and opposing faces  212 B,  214 B of the maxillary piece  212  and mandibular piece  214 , since additional space to provide attachment portions for the relative position adjustment members  224 B is no longer required. 
     Furthermore, due to the wing portions  224  being detachably attached to the wing attachment portions  220 , vertical dimensions of the wing portions  224  can themselves be adjusted by attaching other wing portions  224  of a different vertical dimension to the attachment faces  220 A of the wing attachment portions  220 . Thus, for example as illustrated in  FIG. 10B , the wing portions  224  are able to be abutted against the stopper portions  216  with certainty by setting the position of the upper end of the wing portions  224  higher than the position of the upper end of the stopper portions  216 . 
     Note that in the present exemplary embodiment, the attachment faces  220 A of the wing attachment portions  220  lie in substantially the same plane as the opposing face  214 B of the mandibular piece  214 . This makes for easier cleaning when maintenance is performed on the mouthpiece  210  by enabling cleaning of the attachment faces  220 A of the wing attachment portions  220  to be performed at the same time as cleaning of the opposing face  214 B of the mandibular piece  214 . 
     Second Exemplary Embodiment 
     Next, explanation follows regarding a mouthpiece according to a second exemplary embodiment of the third aspect, with reference to  FIG. 11A  and  FIG. 11B . Note that explanation will be omitted for configuration similar to that of the first exemplary embodiment. 
     In a mouthpiece  230  of the present exemplary embodiment, as illustrated in  FIG. 11A  and  FIG. 11B , wing portions  240  are formed at an outer wall face  234 A of a mandibular piece  234  so as to extend toward a maxillary piece  232 . The wing portions  240  are adjustable in position between tooth positions  6  to  7  of the mandibular piece  234  that is at an anterior side from stopper portions  236  by use of screws  242 . 
     Moreover, anchor portions  246 , which are configured by fitting grooves are formed along an outer periphery of side faces (namely, end faces at a posterior side of dentition) of the wing portions  240  for attaching relative position adjustment members  244 . The relative position adjustment members  244  each includes a cover member  244 A that extends along the extension direction of the wing portions  240 , and a clamped portion  244 B that is provided at a substantially central portion in the extension direction of the cover member  244 A and that extends in a direction substantially orthogonal to the cover member  244 A. 
     Note that an extension length (namely, a vertical dimension) of the cover members  244 A is substantially the same as an extension length (namely, a vertical dimension) of the wing portions  240 , or longer (taller) than the extension length (namely, the vertical dimension) of the wing portions  240 . 
     Fitting portions  248  are formed along an outer periphery of the side faces (namely, end faces at an anterior side of the dentition) of the cover members  244 A. As illustrated in  FIG. 11B , the cover members  244 A of the relative position adjustment members  244  are detachably attached to the wing portions  240  by fitting portions  248  being fitted into anchor portions  246 . Note that retention means such as hooked portions may be provided at the fitting portions  248  to maintain the fitted state thereof in the anchor portions  246 . 
     When the cover members  244 A of the relative position adjustment members  244  are attached to the wing portions  240 , clamped portions  244 B of the relative position adjustment members  244  are mounted to opposing faces  234 B of the mandibular piece  234 . Thus in a closed mouth state, the clamped portions  244 B of the relative position adjustment members  244 B are clamped between an opposing face  232 B of the maxillary piece  232  and the opposing face  234 B of the mandibular piece  234 . A gap therefore arises between the maxillary piece  232  and the mandibular piece  234 . 
     Note that when the mouthpiece  230  is being worn, movement to a posterior side of the wing portions  240  is restricted by side faces (namely, end faces at the posterior side of the dentition) of the cover members  244 A of the relative position adjustment members  244  abutting side faces (namely, end faces at an anterior side of the dentition) of the stopper portions  236 . In other words, the mandibular piece  234  (and hence the mandible) is positioned by the wing portions  240 , the cover members  244 A, and the stopper portions  236  so that the mandibular piece  234  does not move to the posterior side with respect to the maxillary piece  232  (and hence the maxilla). 
     According to the present exemplary embodiment, the relative position adjustment members  244  are detachably attached to the wing portions  240 , thereby enabling the gap between the maxillary piece  232  and the mandibular piece  234  to be appropriately adjusted by replacing the relative position adjustment members  244  with others equipped with clamped portions  244 B of a different thickness. 
     According to the present exemplary embodiment, movement of the wing portions  240  to the posterior side is restricted by the cover members  244 A abutting the stopper portions  236 . Thus the gap between the stopper portions  236  and the wing portions  240 , namely a relative position of the maxillary piece  232  and the mandibular piece  234 , can be adjusted by replacing the relative position adjustment members  244  with others that have different widths (namely, lengths from the anterior side end faces to the posterior side end faces) of the cover members  244 A or different angles at the posterior side end faces abutting the stopper portions  236 . 
     Furthermore, the vertical dimension of the wing portions  240  (and the cover members  244 A) can be adjusted by replacing the relative position adjustment members  244  with others that have different extension lengths (namely, vertical dimensions) of the cover members  244 A. This means that, for example as illustrated in  FIG. 11B , the wing portions  240  (and the cover members  244 A) can be made to abut the stopper portions  216  with certainty by setting the position of an upper end of the respective cover members  244 A higher than the position of the upper end of the stopper portions  236 . 
     Moreover, in the present exemplary embodiment, the relative position adjustment members  244  are clamped by the stopper portions  236  and the wing portions  240  by abutting the cover members  244 A against the stopper portions  236  when the mouthpiece  230  is being worn. This enables the relative position adjustment members  244  to be suppressed from dropping out from the wing portions  240 . 
     Furthermore, in the present exemplary embodiment, the wing portions  240  to which the relative position adjustment members  244  are attached are provided at the outer wall face  234 A of the mandibular piece  234 . There is accordingly a lower risk of being swallowed by the patient even if the relative position adjustment members  244  were to dropout when the mouthpiece  230  is being worn than in configurations in which the wing portions  240  are provided at the inner wall face. 
     Third Exemplary Embodiment 
     Explanation follows regarding a mouthpiece according to a third exemplary embodiment of the third aspect, with reference to  FIG. 12A  and  FIG. 12B . Note that explanation of configuration similar to that of the first exemplary embodiment and the second exemplary embodiment will be omitted. 
     As illustrated in  FIG. 12A  and  FIG. 12B , in a mouthpiece  250  of the present exemplary embodiment, stopper attachment portions  258  to which stopper portions  256  are attached are formed projecting from an outer wall face  252 A of a maxillary piece  252  of the mouthpiece  250 . The stopper attachment portions  258  are provided at the outer wall face  252 A at the tooth positions  6  to  7  at the maxillary piece  252 , and each includes a rail member  260  that has a T-shaped profile in cross-section and extends along the dentition. 
     The stopper portions  256  each includes a stopper  256 A formed with a rail groove  262  at a posterior side of the dentition of the inner wall face, and a relative position adjustment member  256 B that extends in a direction orthogonal to an inner wall face of the stopper  256 A. Note that the rail groove  262  is provided along the inner wall face of each of the stoppers  256 A, and one end of the rail groove  262  configures an opening at the posterior side of the stopper  256 A. 
     As illustrated in  FIG. 12B , the stopper portions  256  are detachably attached to the stopper attachment portions  258  by the rail members  260  being fitted into the rail grooves  262  of the stopper portions  256  from the posterior side. Note that a retention means may be provided at the rail members  260  to maintain the fitted state thereof in the rail grooves  262 . 
     When the stopper portions  256  are attached to the stopper attachment portions  258 , the relative position adjustment members  256 B of the stopper portions  256  are mounted to an opposing face  252 B of the maxillary piece  252 . Thus in a closed mouth state, the relative position adjustment members  256 B are clamped between the opposing face  252 B of the maxillary piece  252  and an opposing face  254 B of mandibular piece  254 . A gap therefore arises between the maxillary piece  252  and the mandibular piece  254 . 
     Note that when the mouthpiece  250  is being worn, movement to a posterior side of wing portions  264  is restricted by side faces (namely, end faces at a posterior side of the dentition) of wing portions  264  abutting side faces (namely, end faces at an anterior side of the dentition) of the stopper portions  256 . In other words, the mandibular piece  254  (and hence the mandible) is positioned by the wing portions  264  and the stopper portions  256  so that the mandibular piece  254  does not move to the posterior side with respect to the maxillary piece  252  (and hence the maxilla). 
     In the present exemplary embodiment, the stopper portions  256 , that are formed integrally with relative position adjustment members  256 B, are detachably attached to the stopper attachment portions  258  of the maxillary piece  252 . This enables the gap between the maxillary piece  252  and the mandibular piece  254  to be appropriately adjusted by replacing the stopper portions  256  with others equipped with relative position adjustment members  256 B of a different thickness. 
     Moreover, in the present exemplary embodiment the relative position adjustment members  256 B are provided at the stopper portions  256 . This enables the thicknesses and widths of the maxillary piece  252  and the mandibular piece  254  to be thinner than in configurations in which the relative position adjustment members  256 B are attached to the outer wall faces  252 A,  254 A and opposing faces  252 B,  254 B of the maxillary piece  252  and mandibular piece  254 , since additional space to provide attachment portions for the relative position adjustment members  256 B is not required. 
     Moreover, in the present exemplary embodiment, the stopper portions  256  are attached to the stopper attachment portions  258  by fitting the rail members  260 , from the posterior side, into the rail grooves  262  formed at the posterior side of the stoppers  256 A. This enables the stopper portions  256  to be easily attached to or detached from the stopper attachment portions  258  when the mouthpiece  250  is not being worn. 
     Furthermore, when the mouthpiece  250  is being worn, the stopper portions  256  can be suppressed from dropping out of the stopper attachment portions  258  due to the wing portions  264  abutting the end faces at the anterior side of the stopper portions  256  (namely, the stoppers  256 A). 
     Fourth Exemplary Embodiment 
     Next, explanation follows regarding a mouthpiece according to a fourth exemplary embodiment of the third aspect, with reference to  FIG. 13A  and  FIG. 13B . Note that explanation will be omitted of configuration similar to that of the first to the third exemplary embodiments. 
     In a mouthpiece  270  of the present exemplary embodiment, as illustrated in  FIG. 13A  and  FIG. 13B , stopper portions  276  are formed integrally to an outer wall face  272 A of a maxillary piece  272 . Moreover, anchor portions  280 , configured by rectangular projections to which relative position adjustment members  278  are attached to, are formed projecting out to an anterior side from side faces (namely, end faces at an anterior side of the dentition) of the stopper portions  276 . 
     The relative position adjustment members  278  include cover members  278 A having substantially the same vertical dimension as a vertical dimension of the stopper portions  276  (namely, a width of an outer wall face  272 A of the maxillary piece  272 ), and clamped portions  278 B that extend from lower ends of the cover members  278 A in directions orthogonal to the cover members  278 A. 
     A rectangular shaped attachment groove  282  is formed at a side face at a posterior side of each of the cover members  278 A. As illustrated in  FIG. 13B , the cover members  278 A of the relative position adjustment members  278  are detachably attached to the stopper portions  276  by the anchor portions  280  fitting into the attachment grooves  282 . Note that a retention means such as a hooked portion may be provided at the anchor portions  280  to maintain the fitted state of the anchor portions  280  to the attachment grooves  282 . 
     Moreover, through holes serving as anchor portions may be provided in the sides of the stopper portion  276 , and projections may be provided at the sides of the cover member  278 A to fit into the through holes. Furthermore, both through holes and projections serving as anchor portions may be provided at the stopper portions  276 , and projections may be provided at the cover members  278 A to fit into the through holes of the stopper portions  276  and through holes may be provided at the cover members  278 A into which the projections of the stopper portions  276  fit. 
     The clamped portions  278 B of the relative position adjustment members  278  are mounted to an opposing face  272 B of the maxillary piece  272  by attaching the cover members  278 A of the relative position adjustment members  278  to the stopper portions  276 . Thus in a closed mouth state, the clamped portions  278 B of the relative position adjustment members  278  are clamped between the opposing face  272 B of the maxillary piece  272  and an opposing face  274 B of a mandibular piece  274 . A gap therefore arises between the maxillary piece  272  and the mandibular piece  274 . 
     Note that when the mouthpiece  270  is being worn, movement to a posterior side of wing portions  284  is restricted by side faces at an anterior side of the cover members  278  abutting side faces at posterior side of the wing portions  284 . In other words, the mandibular piece  274  (and hence the mandible) is positioned by the wing portions  284 , the cover members  278 A, and the stopper portion  276  so that the mandibular piece  274  does not move to the posterior side of the dentition relative to the maxillary piece  272  (and hence the maxilla). 
     In the present exemplary embodiment, the relative position adjustment members  278  are detachably attached to the stopper portions  276 . This enables the gap between the maxillary piece  272  and the mandibular piece  274  to be appropriately adjusted by replacing the relative position adjustment members  278  with others equipped with clamped portions  278 B of a different thickness. 
     Moreover, according to the present exemplary embodiment, movement to the posterior side of the wing portions  284  is restricted by the cover members  278 A abutting the wing portions  284 . This enables the gap between the stopper portions  276  and the wing portions  284 , namely the relative position of the maxillary piece  272  and the mandibular piece  274 , to be adjusted by replacing the relative position adjustment members  278  with others having a different width (namely, a length from end faces at the anterior side to end faces at the posterior side) of the cover members  278 A or different angles at the end faces at the anterior side that abut the wing portions  284 . 
     Moreover, in the present exemplary embodiment, the relative position adjustment members  278  are clamped by the stopper portions  276  and the wing portions  284  due to the cover members  278 A abutting the wing portions  284  when the mouthpiece  270  is being worn. This enables the relative position adjustment members  278  to be suppressed from dropping out from the wing portions  284 . 
     Other Exemplary Embodiments 
     Note that the third aspect is not limited to the exemplary embodiments described above, and various other exemplary embodiments are possible within the scope of the present disclosure. Moreover, appropriate combinations can be made from the first to the fourth exemplary embodiments. 
     For example, in the second exemplary embodiment, the relative position adjustment members  244  include the cover members  244 A and the clamped portions  244 B, the relative position of the maxillary piece  232  and the mandibular piece  234  is adjusted in the anterior-posterior dentition direction by the cover members  244 A, and the gap between the maxillary piece  232  and the mandibular piece  234  is adjusted by the clamped portions  244 B. 
     However, as illustrated in  FIG. 14A  and  FIG. 14B , the relative position adjustment members  244  may include the cover members  244 A alone. This enables the relative position of a maxillary piece  232  and a mandibular piece  234  to be adjusted only in the anterior-posterior direction of the dentition by replacing the relative position adjustment members  244  with others equipped with cover members  244 A of a different width or a different angle at end faces at posterior sides that abut the stopper portions  236 . Note that in such cases the screws  242  to adjust the position of the wing portions  240  do not need to be provided. 
     Similarly, in the fourth exemplary embodiment, the relative position adjustment members  278  include the cover members  278 A and the clamped portions  278 B, the relative position of the maxillary piece  272  and the mandibular piece  274  is adjusted in the anterior-posterior direction by the cover members  278 A, and the gap between the maxillary piece  272  and the mandibular piece  274  is adjusted by the clamped portions  278 B. 
     However, as illustrated in  FIG. 15A  and  FIG. 15B , the relative position adjustment members  278  may include the cover members  278 A alone. This enables the relative position of the maxillary piece  272  and a mandibular piece  274  to be adjusted only in the anterior-posterior direction by replacing the relative position adjustment members  278  with others equipped with cover members  278 A of a different width or a different angle at the end faces at anterior sides that abut the wing portions  284 . 
     Moreover, in the first exemplary embodiment, the wing portions  224  are attached to the wing attachment portions  220  by fitting the projections  218  of the wing attachment portions  220  into the attachment grooves  226  of the wings  224 A. However, the wing portions  224  may be attached to the wing attachment portions  220  using any method as long as the wing portions  224  are detachably attached to the wing attachment portions  220 . For example, projections may be provided at the wing  224 A side and through holes or the like into which the projections fit provided at the wing attachment portions  220  side. 
     Similarly, the attachment method of the relative position adjustment members  244  to the wing portions  240  in the second exemplary embodiment, the attachment method of the stopper portion  256  to the stopper attachment portion  258  in the third exemplary embodiment, and the attachment method of the relative position adjustment members  278  to the cover members  278 A in the fourth exemplary embodiment are not limited to those of the exemplary embodiments described above. 
     Specifically, for example in the second exemplary embodiment, a configuration may be adopted in which the relative position adjustment members  244  are directly anchored to the wing portions  240  by providing through holes that penetrate in the thickness direction through the clamped portions  244 B of the relative position adjustment members  244 , and inserting the wing portions  240  through the through holes. 
     Moreover, although in the first to fourth exemplary embodiments described above, the position of the wing portions  224 ,  240 ,  264 ,  284  are adjustable by use of the screws  242 , the position of the stopper portions  216 ,  236 ,  256 ,  276  may be made adjustable instead of the wing portions  224 ,  240 ,  264 ,  284 . 
     Furthermore, the positions (namely, angles) of the wing portions  224 ,  240 ,  264 ,  284  or the stopper portions  216 ,  236 ,  256 ,  276  may be made adjustable by rotating the wing portions  224 ,  240 ,  264 ,  284  or the stopper portions  216 ,  236 ,  256 ,  276  with respect to the maxillary piece  212 ,  232 ,  252 ,  272  or the mandibular piece  214 ,  234 ,  254 ,  274 . 
     Moreover, in the first to the fourth exemplary embodiments, the stopper portions  216 ,  236 ,  256 ,  276  are provided at the maxillary piece  212 ,  232 ,  252 ,  272 , and the wing portions  224 ,  240 ,  264 ,  284  are provided at the mandibular piece  214 ,  234 ,  254 ,  274 . However, the wing portions  224 ,  240 ,  264 ,  284  may be provided at the maxillary piece  212 ,  232 ,  252 ,  272 , and the stopper portions  216 ,  236 ,  256 ,  276  provided at the mandibular piece  214 ,  234 ,  254 ,  274 . 
     The shape of the stopper portions  216 ,  236 ,  256 ,  276  may, as with the wing portions  224 ,  240 ,  264 ,  284 , be shaped so as to extend in the direction of the other piece (the maxillary piece or the mandibular piece) that is not provided with the stopper portions  216 ,  236 ,  256 ,  276 . 
     The entire disclosures of Japanese Patent Application Nos. 2016-127904 and 2016-127905 filed Jun. 28, 2016 are incorporated by reference in this specification, and entire disclosure of Japanese Patent Application No. 2016-224519 filed Nov. 17, 2016 is incorporated by reference in this specification. 
     All publications, patent applications and technical standards mentioned in the present specification are incorporated by reference in the present specification to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.