Abstract:
A method of forming a custom mask ( 40 ) includes introducing a deformable material ( 32 ) to an impression mask ( 24 ) and directing the deformable material ( 32 ) against at least a portion of a user&#39;s face within the impression mask ( 24 ). This forms an impression of the user&#39;s face in the deformable material ( 32 ) to form the custom mask ( 40 ). The impression mask ( 24 ) receives the deformable material ( 32 ) and directs the deformable material ( 32 ) against at least a portion of a user&#39;s face within the impression mask ( 24 ) in response to pressure applied to the impression mask ( 24 ). The deformable material ( 32 ) may include a polycaprolactone polymer or an aliphatic polyester. The impression mask ( 24 ) may receive the deformable material ( 32 ) either before the user&#39;s face is brought within the impression mask ( 24 ) or while the user&#39;s face is within the impression mask ( 24 ).

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is related to U.S. application Ser. No. 09/543,405 entitled “Oral Appliance for Improving Breathing and Method of Constructing Same,” U.S. application Ser. No. 09/543,397 entitled “Custom Mask and Method of Forming Same,” U.S. application Ser. No. 09/543,398 entitled “Custom Mask Assembly and Method for Making Same,” and U.S. application Ser. No. 09/543,402 entitled “Device for Improving Breathing and Method of Constructing Same,” all filed Apr. 5, 2000 by W. Keith Thornton. 
     This application is also related to U.S. application Ser. No. 08/594,904, filed Jan. 31, 1996, by W. Keith Thornton and entitled “Device for Improving Breathing,” which is a continuation of U.S. application Ser. No. 08/253,949, filed Jun. 3, 1994, by W. Keith Thornton and entitled “Combination Face Mask and Dental Device for Improved Breathing During Sleep” (now U.S. Pat. No. 5,537,994). 
     This application is also related to U.S. application Ser. No. 08/828,523, filed Mar. 31, 1997, by W. Keith Thornton and entitled “Apparatus for Prevention of Snoring and Improved Breathing During Sleep,” which is a file wrapper continuation of U.S. application Ser. No. 08/363,639, filed Dec. 24, 1994, by W. Keith Thornton and entitled “Apparatus for Prevention of Snoring and Improved Breathing During Sleep” (now abandoned), which is a continuation of U.S. application Ser. No. 08/129,598, filed Sep. 29, 1993, by W. Keith Thornton and entitled “Apparatus for Prevention of Snoring and Improved Breathing During Sleep” (now U.S. Pat. No. 5,427,117). 
     This application is also related to U.S. application Ser. No. 08/787,529, filed Jan. 21, 1997, by W. Keith Thornton and entitled “Method and Apparatus for Adjusting a Dental Device,” which is a file wrapper continuation of U.S. application Ser. No. 08/435,277, filed May 5, 1995, by W. Keith Thornton and Andrew O. Jamieson and entitled “Method and Apparatus for Adjusting a Dental Device” (now abandoned), which is a file wrapper continuation of U.S. application Ser. No. 08/218,719, filed Mar. 24, 1994, by W. Keith Thornton and Andrew O. Jamieson and entitled “Method and Apparatus for Adjusting a Dental Device” (now abandoned). 
     This application is also related to U.S. application Ser. No. 09/333,874, filed Jun. 15, 1999, by W. Keith Thornton and entitled “Device and Method for Improving Breathing and Method for Fitting Same,” which is based on U.S. Provisional Application No. 60/089,628, filed Jun. 16, 1998. 
     This application is also related to U.S. application Ser. No. 09/290,512, filed Apr. 12, 1999, by W. Keith Thornton and entitled “Device for Improving Breathing,” which is a continuation of U.S. application Ser. No. 08/878,998, filed Jun. 19, 1997, by W. Keith Thornton and entitled “Device for Improving Breathing” (now U.S. Pat. No. 5,983,892), which is a continuation of U.S. application Ser. No. 08/582,526, filed Jan. 3, 1996 by W. Keith Thornton and entitled “Device for Improving Breathing” (now abandoned), which is a continuation-in-part of U.S. application Ser. No. 08/253,949. 
     This application is also related to U.S. application Ser. No. 09/396,986, filed Sep. 15, 1999 by W. Keith Thornton and entitled “Device for Improving Breathing and Method of Fitting Same.” 
     This application is also related to U.S. application Ser. No. 09/483,741, filed Jan. 17, 2000 by W. Keith Thornton and entitled “Oral Appliance Having a Bonding Layer and Methods for Fitting and Relining Same.” 
     This application is also related to U.S. application Ser. No. 09/554,771, filed May 16, 2000 by W. Keith Thornton and entitled “Device and Method for Improving Breathing.” 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     This invention relates generally to the field of face masks, and more particularly to a custom mask formed using an impression mask. 
     BACKGROUND OF THE INVENTION 
     Many people experience breathing problems on a recurring basis, which often results in difficulty sleeping, in snoring, or in other more serious conditions such as obstructive sleep apnea. One treatment for such breathing problems involves use of a device inserted into a user&#39;s mouth for extending the user&#39;s lower jaw forward. These devices help to open the user&#39;s breathing passage more fully to allow easier breathing through the user&#39;s nose and mouth. 
     As technology advances and people with breathing problems demand increased performance and comfort, improving the breathing of the users becomes increasingly important. Previous devices for improving breathing include custom masks connected to an associated oral appliance. Such an oral appliance may extend the user&#39;s lower jaw forward to open the breathing passage, while the mask allows air or another gas to be delivered to the user&#39;s nose at positive pressure to further open the breathing passage. Previous masks are often relatively expensive due to the expertise that is often required to design and manufacture the masks and fit them to the users. Furthermore, previous masks have often been fitted to the user&#39;s particular bone structure and facial features poorly, if at all. As a result, previous masks have failed to adequately prevent venting from around the perimeter of the mask, have caused discomfort for the users, and have been ineffective in treating breathing problems such as snoring and sleep apnea. As a result of these and other deficiencies, previous masks are inadequate for the needs of many users who experience breathing difficulties. 
     SUMMARY OF THE INVENTION 
     According to the present invention, problems and disadvantages associated with previous custom masks and methods for making them have been substantially reduced or eliminated. 
     According one embodiment of the present invention, a method of forming a custom mask includes introducing a deformable material to an impression mask and directing the deformable material against at least a portion of a user&#39;s face within the impression mask. This forms a resulting impression of the user&#39;s face in the deformable material to form the custom mask. In a more particular embodiment, the deformable material includes a polycaprolactone polymer or an aliphatic polyester. In another more particular embodiment, the deformable material is introduced to the impression mask before the user&#39;s face is brought within the impression mask. 
     According to another embodiment of the present invention, an impression mask for forming a custom mask receives a deformable material and directs the deformable material against at least a portion of a user&#39;s face within the impression mask in response to pressure applied to the impression mask. The impression mask forms a mold of at least the portion of the user&#39;s face in the deformable material to form the custom mask. In a more particular embodiment, the deformable material includes a polycaprolactone polymer or an aliphatic polyester. In another embodiment, the impression mask may receive the deformable material before the user&#39;s face is brought within the impression mask or while the user&#39;s face is within the impression mask. 
     The custom mask and method of making it according to the present invention provide important technical advantages. In contrast to prior techniques, the impression mask of the present invention allows the custom mask to be made and fitted to a user relatively quickly and easily, with little expertise required, typically resulting in better efficiency for clinical professionals and reduced cost to users. In contrast to previous masks, the custom mask of the present invention is fitted substantially optimally to the particular user&#39;s facial structure and features. As a result, the custom mask provides improved fit, reduced venting, increased comfort, and better performance, whether in treating breathing problems such as snoring and sleep apnea or for any other suitable purpose for which the custom mask is used. Other technical advantages will be readily apparent to those skilled in the art. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a more complete understanding of the present invention and its advantages, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features and wherein: 
     FIG. 1 illustrates an exemplary impression mask being registered in position relative to an associated oral appliance; 
     FIG. 2 illustrates an exemplary custom mask assembly; and 
     FIG. 3 is a flow chart illustrating an exemplary method of making a custom mask assembly that is registered in position relative to an associated oral appliance. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates an exemplary system  10  for constructing a face, nose, or other mask that is registered relative to an associated custom, non-custom, or other oral appliance. In one embodiment, the oral appliance includes at least an upper arch  12 . A lower arch (not explicitly shown) may be coupled to upper arch  12  in any appropriate manner and for any suitable purpose. For example only and not by way of limitation, upper arch  12  may be coupled to a lower arch using a suitable deformable material as described in co-pending U.S. Application No. 09/543,405, filed on Apr. 5, 2000 for a “Device for Improving Breathing and Method of Constructing Same,” may be coupled to a lower arch using a suitable hooking mechanism as described in U.S. Pat. No. 5,954,048, or may be coupled to a lower arch in any other appropriate manner. In one embodiment, a lower arch may be coupled to upper  12  so that the lower arch may be secured in a fixed forward position relative to upper arch  12  to extend the user&#39;s lower jaw forward. This opens the user&#39;s breathing passage and helps to reduce or eliminate breathing problems such as snoring and sleep apnea. 
     An outwardly extending post  14  is coupled to or integrally formed with upper arch  12  and includes a tapered portion  16  for force fitting post  14  into hollow  36  of registration cap  18 . Although tapered portion  16  of post  14  is shown as being rounded to some extent, the present invention contemplates tapered portion  16  being angled or having another shape appropriate to cooperate with the internal shape of hollow  36  in registration cap  18 . The present invention further contemplates a latch, knob or other protrusion, or another suitable mechanism to help secure registration cap  18  to tapered portion  16  to. Instead of or in addition to the above, a screw or other suitable fastener  20  may permanently or removably couple registration cap  18  to post  14 . The tapered portion  16  may be integral to the remainder of post  14 , may be screwed or otherwise coupled to the remainder of post  14 , may rotate relative to the remainder of post  14  to adjust the forward position of an associated lower arch (as described in U.S. Pat. No. 5,954,048, for example), or may have any other suitable relationship to the remainder of post  14 . 
     In one embodiment, registration cap  18  includes one or more spacers  22  used for registering the position of registration cap  18 , and thus the position of upper arch  12 , relative to an impression mask  24 . Providing accurate registration between impression mask  24  and upper arch  12  allows a custom mask to be formed using impression mask  24  such that the custom mask and upper arch  12  will be properly horizontally spaced, vertically spaced, rotated, and otherwise configured relative to one another to properly fit the particular user&#39;s bone structure and facial features. With previous custom masks, proper fit has been the primary obstacle to achieving reduced venting from around the mask perimeter, sufficient comfort for the user, and other treatment goals. The present invention overcomes these obstacles, providing an important technical advantage over previous mask construction techniques. As shown, registration cap  18  may include an extended arm  26  for coupling the upper arch  12  to one or more other components for improving the user&#39;s breathing, as described more fully in co-pending U.S. application Ser. No. 09/543,402 filed Apr. 5, 2000 for a “Device for Improving Breathing and Method of Constructing Same.” 
     Impression mask  24  includes an opening  28  shaped to cooperate with the shape of registration cap  18  and spacers  22 . In a particular embodiment, the spacers  22  are substantially cylindrical and opening  28  of face shield  26  includes cooperating rounded contours  30  to receive spacers  22 . However, the present invention contemplates one or more spacers  22  having any appropriate shape, and opening  28  having any appropriate cooperating shape, according to particular needs. Opening  28  of impression mask  24  may seat on registration cap  18  and spacers  22  relatively loosely, relatively tightly, or in any other suitable manner. Although spacers  22  are described, the present invention contemplates registration cap  18  without spacers  22 , in which case opening  28  may be shaped to seat impression mask  24  onto registration cap  18  alone. Impression mask  24  may be formed from an acrylic or other suitable material. 
     Before, during, or after impression mask  24  is seated onto registration cap  18 , a deformable material  32  is heated or otherwise placed in a deformable state and placed within impression mask  24  so as to cover appropriate portions of the user&#39;s face when deformable material  32  is brought into contact with the user&#39;s face. The deformable material  32  may be placed in its deformable state before or after being placed within impression mask  24 . In one embodiment, deformable material  32  covers and takes an impression of at least a portion of the user&#39;s nose and surrounding regions to produce, once deformable material  32  cools and hardens, a custom nose mask appropriate for delivering air or another suitable gas to the user&#39;s nose from a continuous positive air pressure (CPAP) system or other external source. Impression mask  24  may include a deeper concave portion  34  to receive the user&#39;s nose, and preferably includes suitable holes  36  to allow excess deformable material  32  to escape as an impression is taken. Deformable material  32  may couple with at least portions of registration cap  18 , spacers  22 , or both registration cap  18  and the spacers  22  to form an integral assembly incorporating at least the custom mask and registration cap  18 . In one embodiment, deformable material  32  may substantially surround registration cap  18  and spacers  22 , for increased stability or otherwise. 
     A suitable deformable material  32  may include, for example only and without limitation, methylmethacrylate, the polycarbonate resin thermoplastic such as that sold as LEXAN, the ethylene-vinyl acetate copolymer resin sold under the name ELVAX, a thermoplastic polymer such as polycaprolactone, or other suitable deformable material. These materials are known in substantially different contexts to those skilled in the art and other suitable materials may be used without departing from the intended scope of the present invention. In a particular embodiment, deformable material  32  includes one or more of the polycaprolactone polymers or other aliphatic polyesters as described in U.S. Pat. Nos. 5,112,225 and 4,784,123, and also in product literature distributed by UNION CARBIDE CORPORATION. One or more polycaprolactone polymers may have the formula:                           
     where R is an aliphatic hydrocarbon and n may range between approximately 300 to approximately 650. Polycaprolactone polymers display desirable dimensional stability and thermoplasticity during cooling, biocompatibility, and other characteristics making them suitable for uses described herein. However, the present invention contemplates any suitable polycaprolactone polymer, possibly including one or more polycaprolactone polymers with other suitable formulas. 
     In a particular embodiment, deformable material  32  includes one or more of the TONE P-700, TONE P-767, or TONE P-787 polycaprolactone polymers manufactured by UNION CARBIDE CORPORATION, singly or in any combination. In a more particular embodiment, deformable material  32  may include approximately thirty parts by volume of TONE P-700 and sixty parts by volume of TONE P-767, together with approximately ten parts by volume of one or more other polymers, depending upon the application and particular needs. A light cured material, another polymer, or any other suitable material, such as a filler, coloring agent, stabilizer, antioxidant, or antimicrobial agent, may be used to replace or combine with a polycaprolactone polymer in forming deformable material  32  having any appropriate characteristics, properties, or uses. The present invention contemplates deformable material  32  including any suitable mixture or other combination of polycaprolactone polymers, other polymers, and other suitable materials, compounds, or compositions. 
     The TONE set of polycaprolactone polymers are described in U.S. Pat. Nos. 5,112,225 and 4,784,123, and in product literature distributed by UNION CARBIDE CORPORATION, as including homopolymers, block copolymers, graft copolymers, or other polymers containing epsilon-caprolactone. Polymerization may be initiated using a diol, for example and without limitation, ethylene glycol, diethylene glycol, neopentyl glycol, butane diol, hexane diol, or any other appropriate diol. The diol may have the formula: 
     
       
         HO—R—OH  (2) 
       
     
     where R is an aliphatic hydrocarbon. 
     Deformable material  32  may begin as extruded pellets, beads, or rods of uniform, similar, or differing size, or in other suitable form. Deformable material  32  is heated in a microwave oven, in water or other non-solvent neutral liquid, or in any other suitable manner to between approximately 140° F. and approximately 180° F. to place deformable material  32  in its deformable state. Deformable material  32  may be maintained in this deformable state until the pellets, beads, or rods congeal, coalesce, or otherwise combine to form a deformable mass capable of assuming shape and configuration desired. The deformable material  32  may be placed in its deformable state before, during, or after deformable material  32  is introduced to impression mask  24 . Deformable material  16  mixes, bonds, reacts, combines, or otherwise couples with the material used to form registration cap  18  while deformable material  32  is in a liquid or other deformable state. In one embodiment, deformable material  32  chemically bonds to registration cap  18 , to spacers  22 , or to both registration cap  18  and spacers  22  to produce an integral piece incorporating a custom mask and registration cap  18 . This assembly may be coupled permanently to the associated oral appliance or alternately removed and re-coupled in accordance with particular needs. 
     In one embodiment, the upper arch  12  is inserted into the user&#39;s mouth and the registration cap  18  is coupled to the tapered portion  16  of post  14  in a suitable manner. Deformable material  32  is applied to impression mask  24 , opening  28  of impression mask  24  is properly seated on registration cap  18  and spacers  22 , and impression mask  24  is pressed or otherwise brought in contact with a suitable portion of the user&#39;s face. Impression mask  24  is adjusted, if necessary, to the proper or other appropriate position relative to upper arch  12 . Deformable material  32  mixes, bonds, reacts, combines, or otherwise couples to the registration cap  18  and spacers  22  while it is in a deformable state. Deformable material  32  is then allowed to cool and harden to produce a custom mask that is in a fixed position relative to upper arch  12 . Alternatively, deformable material  32  may be introduced into impression mask  24  after impression mask  24  has been seated on registration cap  18 . The same or a different deformable material  32  may be used, after formation of the custom mask, to couple the custom mask to registration cap  18 . Deformable material  32  may be delivered while in a liquid, melted, or other deformable state using a syringe, hypodermic needle, hot glue gun, or other delivery device or technique. 
     Impression mask  24  may remain in contact with the user&#39;s face or be removed before, during, or after the deformable material  32  fully cools and hardens. Deformable material  32  may be used to form a custom mask in the user&#39;s home, in the office of a dental, medical, or other clinical professional, or in any other suitable location. While a particular technique is described, the present invention contemplates any appropriate technique for constructing a custom mask that is accurately registered relative to the position of an associated oral appliance. 
     FIG. 2 illustrates an exemplary custom mask assembly  38 , which includes custom mask  40 , constructed according to the present invention. As discussed above, custom mask assembly  38  provides important advantages over previous custom masks such as reduced venting, increased comfort, and other benefits. Although custom mask  40  is described primarily as being formed in connection with an oral appliance and the registration of its position relative to the oral appliance, impression mask  24  may be advantageously used to form custom mask  40  with or without an oral appliance or the registration of its position relative to the oral appliance. Furthermore, although custom mask  40  is described primarily for use in improving a user&#39;s breathing in combination with a CPAP system, the present invention contemplates custom mask  40  having any appropriate use or uses, according to particular needs. 
     FIG. 3 is a flow chart illustrating an exemplary method of constructing a custom mask registered in position relative to an associated oral appliance. The method begins at step  100 , where the user or a clinical professional couples registration cap  18  to post  14  of upper arch  12 . At step  102 , upper arch  12  is inserted into the user&#39;s mouth to substantially fix the position of registration cap  18  relative to post  14  and thus the user&#39;s upper jaw. The present invention contemplates registration cap  18  being coupled to upper arch  12  before or after upper arch  12  is inserted into the user&#39;s mouth. At step  104 , deformable material  32  is heated or otherwise placed into a deformable state and, at step  106 , deformable material is introduced to impression mask  24 . In a particular embodiment, deformable material  32  is placed in the impression mask  24  such that deformable material  32  will substantially surround at least a portion of the user&#39;s nose including the nostrils and will also surround or otherwise couple to registration cap  18 , spacers  22 , or both registration cap  18  and spacers  22 . 
     Impression mask  24  is seated on registration cap  18  at step  108  to substantially fix the position of impression mask  24  relative to post  14  and thus the user&#39;s upper jaw. At step  110 , the impression mask  24  is pressed against or otherwise brought in contact with the user&#39;s face to form a suitable impression of the user&#39;s nose and appropriate surrounding regions, registered in position relative to post  14  and thus the user&#39;s upper jaw. As described above, excess deformable material  32  may escape through holes  36  in impression mask  24 . Deformable material  32  may instead be placed in impression mask  24  after impression mask  24  has been properly seated on the registration cap  18 . Deformable material  32  couples to registration cap  18 , spacers  22 , or both registration cap  18  and spacers  22  at step  112 . 
     At step  114 , deformable material  32  is permitted to cool and harden, while in contact with the user&#39;s face or after removal from the user&#39;s face, to produce an integral custom mask assembly  38 . At step  116 , custom mask assembly  38 , incorporating both the custom mask and registration cap  18 , is separated from impression mask  24  and custom mask assembly  38  is ready for use in treating snoring, sleep apnea, or any other appropriate breathing problem. As described above, custom mask assembly  38  may be integral to or separate from upper arch  12 . At step  118 , assuming assembly  38  is not permanently coupled to upper arch  12 , assembly  38  may be repeatedly separated from and re-coupled to upper arch  12  as often as necessary or desirable to improve the user&#39;s breathing, according to particular needs. 
     Although the present invention has been described above in connection with several embodiments, it should be understood that a plethora of changes, substitutions, variations, alterations, transformations, and modifications may be suggested to one skilled in the art, and it is intended that the present invention encompass such changes, substitutions, variations, alterations, transformations, and modifications as fall within the spirit and scope of the appended claims.