Abstract:
The dental splints are used for treating temporomandibular disorders, clenchers, bruxism and headaches resulting from improper alignment of the jaws. The dental splints include a maxillary splint and a mandibular splint. Both splints are formed from stents having a U-shaped trough filled with a dental acrylic and cured in situ on the patient&#39;s maxillary teeth and mandibular teeth, respectively. The apparatus includes a maxillary plane analyzer and a holding plate. The holding plate is a U-shaped plate having a central slot for receiving a stem of the plane analyzer and a plurality of recesses for receiving temporary cleats extending from the maxillary stent. The plane analyzer includes a handle, a U-shaped base mounted on the handle and including a pair of arms adapted for extending to either side of the mandible, a stem extending between the arms of the base, and a cruciform upright mounted on the handle.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to dental devices, and more particularly to an orthotic dental splint, and to an apparatus and method of making the splints to treat temporomandibular disorders, clenchers, bruxism and headaches that can be used by the dentist to make the splints in the dentist&#39;s office instead of a dental laboratory.  
         [0003]     2. Description of the Related Art  
         [0004]     Dental ailments encompass a variety of disorders that require treatment ranging from simple methods to invasive surgery. Temporomandibular disorder (TMD) is one such dental problem. Proper functioning of the lower jaw is dependent, in part, upon temporomandibular joints and associated muscles. The temporomandibular joints are disposed on each side of the jaw and connect the lower jaw to the temporal bones of the skull. The temporomandibular joints (TMJs) are the most used joints in the body; among other functions, the TMJs are used to speak, chew, swallow and yawn. Improper alignment of the lower jaw is recognized by jaw pain, headaches, and other signs and symptoms of discomfort in the patient.  
         [0005]     Temporomandibular disorder may be treated using non-invasive techniques, modalities, and devices, such as splints. Invasive measures are usually only resorted to when more conservative measures prove ineffective in relieving the severity of the patient&#39;s condition. Splints relieve stress on muscle and joints and often times are used to mitigate the effects of clenching and grinding teeth. Splints may be purchased over the counter. However, more traditionally, splints are custom-made for each patient. Custom-made splints require a procedure having a number of steps, including: first, an impression is made of the patients, maxillary and mandibular teeth using irreversible hydrocolloid or similar product; next, a model is made from the impression; then a bite is taken in wax or a suitable alternative material which articulates the models together in centric relation; finally, the bite model and facebow mounting are sent to a laboratory for fabrication of an upper or lower splint having both maxillary and mandibular impressions. Thus, after a week or less, the patient must return to the office to have the dentist fit the splint in the mouth.  
         [0006]     The room for error is vast. If the doctor does not have experience in manipulating the patient in centric relation, errors in splint fabrication can occur. Also, face-bows aligned by pointers or the nasion can be shifted by the patient due to pain or displeasure with the device. Also, new, inexperienced dentists find it difficult to use and balance face-bows, often resulting in such inexperienced dentists opting out of treating TMD because of the difficulty in correcting alignment and finding balance in the temporomandibular joints. Thus, dental splints and an apparatus and method for making the splints that can be easily and quickly done in the office while the patient waits is desired.  
       SUMMARY OF THE INVENTION  
       [0007]     The dental splints are used for treating temporomandibular disorders, clenchers, bruxism and headaches resulting from improper alignment of the jaws. The dental splints include a maxillary splint and a mandibular splint. Both splints are formed from stents having a U-shaped trough filled with a dental acrylic and cured in situ on the patient&#39;s maxillary teeth and mandibular teeth, respectively. The apparatus includes a maxillary plane analyzer and a holding plate. The holding plate is a U-shaped plate having a central slot for receiving a stem of the plane analyzer and a plurality of recesses for receiving temporary cleats extending from the maxillary stent. The plane analyzer includes a handle, a U-shaped base mounted on the handle and including a pair of arms adapted for extending to either side of the mandible, a stem extending between the arms of the base, and a cruciform upright mounted on the handle.  
         [0008]     In use, the maxillary stent is positioned on the holder plate by inserting temporary cleats extending from the lower surface of the stent into recesses defined in the holding plate. A dental acrylic is placed in the maxillary stent trough. The holding plate is mounted on the stem of the maxillary plane analyzer. The arms of the analyzer are placed on opposite sides if the patient&#39;s mandible, and the analyzer is raised or lowered to align the crossbar of the cruciform upright level with the patient&#39;s eyes. This aligns the maxillary stent in the patient&#39;s occlusal plane, so that the patient inserts his teeth into the U-shaped trough and the acrylic is allowed to cure, forming a maxillary splint. The analyzer, holding plate, and splint are removed from the patient&#39;s mouth, the splint is removed from the holding plate, and the cleats are broken off or removed from the maxillary splint.  
         [0009]     The maxillary splint is then inserted into the patient&#39;s mouth. Dental acrylic is placed in the U-shaped trough of the mandibular stent, which is then inverted and placed over the mandibular teeth in alignment with the maxillary splint. The acrylic in the mandibular stent is allowed to cure to form the mandibular splint. The mandibular splint is then removed, and any rough surfaces are smoothed. The teeth cavities in the splints cause the patient to maintain the maxilla and the mandible in proper alignment, keeping maximum registry and alignment of the maxillary and mandibular teeth, thereby alleviating the pain associated with TMD, and relieving the patient from pain and discomfort associated with clenching, bruxism, and resulting headaches.  
         [0010]     These and other features of the present invention will become readily apparent upon consideration of the following specification and drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]      FIG. 1  is an environmental, perspective view of an apparatus for making dental splints according to the present invention.  
         [0012]      FIG. 2  is an exploded perspective view of an apparatus for making dental splints according to the present invention.  
         [0013]      FIG. 3  is a front view of an apparatus for making dental splints according to the present invention.  
         [0014]      FIG. 4  is a top view of a holding plate according to the present invention.  
         [0015]      FIG. 5  is a rear view of a holding plate according to the present invention.  
         [0016]      FIG. 6  is a side view of the maxillary stent according to the present invention exploded from the holding plate.  
         [0017]      FIG. 7  is a perspective view of a maxillary stent according to the present invention.  
         [0018]      FIG. 8  is a perspective view of a mandibular stent according to the present invention.  
         [0019]      FIG. 9  is a side view of a maxillary splint according to the present invention.  
         [0020]      FIG. 10  is a side view of a mandibular splint according to the present invention. 
     
    
       [0021]     Similar reference characters denote corresponding features consistently throughout the attached drawings.  
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0022]     The present invention is a pair of dental splints for treating temperomandibular joint disorder and similar conditions involving the relation of the maxilla and mandible, together with an apparatus and method for making dental splints that permits fabricating the splints in the dental practitioner&#39;s office instead of a dental laboratory. The structure of the splints will become clear by explaining the apparatus and method of making the splints.  
         [0023]     Referring to  FIGS. 1, 2  and  3 , the apparatus is designated generally as  100  in the drawings. The apparatus  100  includes a maxillary plane analyzer  200 , a holding plate  300  and a maxillary stent  400 . The holding plate  300  removably holds the stent  400 . The dentist uses the analyzer  200  to determine the patient&#39;s occlusal plane and orient the stent  400  in the proper angle on the patient&#39;s maxilla.  
         [0024]     The analyzer  200  is a support and manipulating body having a handle or lever  215 , a cruciform upright  230 , and a U-shaped base having mandible arms  210 . The lever  215  has a curved end or stem  240  and a handle end  220 ; the upright  230  and mandible arms  210  are disposed adjacent the curved end  240 . The mandible arms  210  and the upright  230  serve as orientation guides. The mandible arms  210  are designed to align with the mandible and the crossbar of the cruciform upright  230  is aligned with the patient&#39;s eyes, at eyelevel. The lever  215  is arched or bent, allowing a dentist or other user to hold the handle end  220  without obstructing the view of the stem  240 . The stem  240  is designed to removably receive and support the holding plate  300 .  
         [0025]     As shown in  FIGS. 4 and 5 , the holding plate  300  is a generally U-shaped plate having a top surface, a bottom surface, alignment holes  320  or recesses, and a central slot or channel  340  depending from the bottom surface of the plate  300 . The channel  340  of the holding plate  300  receives and retains the curved end  240  of the analyzer  200  by friction or by using fasteners, such as snaps, spring loaded attachments, screws, a wingnut, etc. The holding plate  300  removably receives the stent  400 , which is retained by the alignment holes  320 .  
         [0026]     Referring now to  FIGS. 6 and 7 , a cured maxillary stent  400  provides a frame dimensioned and configured to correspond to the arch of the patient&#39;s maxilla. The maxillary stent  400  is made of a hard acrylic, a cured methacrylate, an orthodontic resin, plastic material or other similar material. The stent  400  is a U-shaped frame having a base with an upper side  410  and a lower side  412 . A pair of parallel walls extend normal to the upper side  410  of the base to define a U-shaped trough. The trough is designed to fit the arch of the maxilla. The walls of the trough are sufficiently spaced apart to receive an uncured dental acrylic and accommodate the maxillary teeth once the stent frame  400  is placed on the maxilla. The lower side  412  of the stent  400  is flat with cleats  420  extending therefrom.  
         [0027]     The cleats  420  correspond with the alignment holes  320  of the holding plate  300 . The cleats  420  removably hold the cured maxillary stent frame  400  to the holding plate  300  and secure the stent frame  400  as it is delivered into and removed out of the patient&#39;s mouth. The cleats  420  are removed once the dental acrylic placed in the stent  400  is cured and the maxillary splint  450 , shown in  FIG. 9 , is formed. The cleats  420  may be any temporary attachment member that correspond with the alignment holes  320  of the holding plate  300 . The number of cleats  420  corresponds with the number of alignment holes  320  of the holding plate  300 . Although the drawings show six cleats, there is no specific number for each the alignment holes  320  and cleats  420 . As an added form of stability, an additional cleat  420  and alignment hole  320  may be disposed in the center of the maxillary stent  400  and the holding plate  300 , respectively, nearest the flat end of each. The cleats  420  may be of any shape, such as pyramidal, as shown in the figures, but is preferably cylindrical in shape with a slight six to eight degree taper at the bottom end, which is farthest from the plate  300 . Alternatively, instead of cleats  420 , the maxillary stent  400  may have a flange, while the holding plate  300  may have a corresponding flange that interconnects to removably connect the stent  400  to the holding plate  300 .  
         [0028]     To assemble the apparatus  100  and create the maxillary splint  450 , the holding plate  300  is removably attached to the curved end  240  of the maxillary plane analyzer  200  by sliding the curved end  240  into the slot or channel  340 . The maxillary stent frame  400  is then placed on the holding plate  300  so that the cleats  420  are removably received within the alignment holes  320  of the holding plate  300 . Finally, the trough on the upper side  410  of the stent  400  is filled with the uncured methacrylate or other dental acrylic and is oriented on the patient&#39;s maxilla using the analyzer  200 .  
         [0029]     The proper orientation of the stent  400  on the maxilla, and consequentially the proper orientation of a mandibular stent  500  on the mandible, is established when the patient&#39;s occlusal plane is located. The analyzer  200  determines the occlusal plane of the patients&#39; mouth based on the occlusal surface of the maxilla. The analyzer has three orientation guides to locate the proper occlusal surface of the maxilla.  
         [0030]     The first point of reference places the curved portion  240  of the lever  215  parallel with the occlusal surface of the maxilla. The labial surface of the upper front central incisors are used as reference points. The second orientation guide is based on the alignment of the mandible arms  210  with the patient&#39;s mandible. The third orientation guide places the crossbar of the cruciform upright  230  in registry with the eyes, specifically the crossbar of the upright  230  is aligned with an imaginary horizontal line drawn from pupil to pupil. The proper orientation of the maxillary stent  400  on the maxilla is important, because if the occlusal angle is too steep, the maxillary splint  450  will not compensate for the pull of the muscle, and if it is too flat, the problem with the joints would still persist. The occlusal plane angle must conform to the arch of the closure of the mandible to ensure a balance in the system.  
         [0031]     The proper occlusal plane of the mouth is based on the maxilla, since the maxilla is stationary, unlike the variable mandible. However it may be possible to determine the proper occlusal plane based on the orientation of the mandible. Once the stent frame  400  is properly oriented on the maxilla, it remains there for a sufficient period of time that the methacrylate, or other dental acrylic, in the trough  410  is cured, thereby forming the maxillary splint  450 .  
         [0032]     As soon as the maxillary splint  450  is cured, the maxillary splint  450  is removed from the maxilla and the holding plate  300 , and the splint is finished. Removing the cleats  420  from the flat side  412  of the stent  400  finishes the splint  450 . The maxillary splint  450 , shown in  FIG. 9 , has a flat lower surface  452 , the cleats  420  being removed from the maxillary stent  400 , and maxillary teeth impressions  454  formed by cured acrylic in the trough side  410  of the maxillary stent  400 . The maxillary splint  450  is then replaced on the maxilla and a mandibular stent  500  is prepared and positioned on the mandible.  
         [0033]     As shown in  FIG. 8 , the mandibular stent  500  is a U-shaped frame and is generally dimensioned and configured to correspond to the arch of the patient&#39;s mandible. The mandibular stent  500  has a U-shaped base having a first side and a second side. The lower side has parallel walls extending from the base creating a trough side  510 ; the upper side  512  of the base is flat. The mandibular stent  500  is made of a hard acrylic, a cured methacrylate, an orthodontic resin, plastic material or other similar material. The trough side  510  of the mandibular stent  500 , like the maxillary stent  400 , receives a quantity of uncured methacrylate or other dental acrylic, and the stent  500  is then disposed on the patient&#39;s mandible and cured in place.  
         [0034]     The proper occlusal surface for the mandibular stent  500  is determined based on the position of the mandibular stent  500  relative to the maxillary splint  450 . As mentioned above, the analyzer  200  determines the occlusal plane of the patient&#39;s mouth based on the occlusal surface of the maxilla. Thus, when the maxillary splint  450  is disposed on the maxillary splint  400 , the maxillary splint  450  acts as the orientation guide for the mandibular stent  500  and consequentially defines the proper occlusal plane for both splints  450  and  550 . To orient the mandibular stent  500  on the mandible, the flat surface  512  of the mandibular stent  500  abuts the flat lower surface  452  of the cured maxillary splint  450 . As with the maxillary splint  450 , the mandibular stent  500  remains on the mandible for a sufficient period of time to cure the methacrylate or other dental acrylic disposed in the trough  510  of the mandibular stent  500 , and an impression of the mandibular teeth is obtained, thereby creating the mandibular splint  550 . The mandibular splint  550 , shown in  FIG. 10 , has a flat upper surface  552  and mandibular teeth impressions  554  formed by curing the methacrylate or other dental acrylic in the trough or lower side  510  of the mandibular stent  500 . Once cured, the mandibular splint  550  is removed from the mandible and finished by smoothing out any sharp edges. The entire process should take less than thirty minutes.  
         [0035]     The stents  400 ,  500  are differentiated from the splints  450 ,  550 , in that the stents  400 ,  500  are a frame made to receive the uncured acrylic. The splints  450 ,  550  are the final product used to determine the occlusal surface and the occlusal plane, and have teeth impressions  454 ,  554  formed therein.  
         [0036]     The proper occlusal plane is achieved when the majority of the maxillary teeth are in contact with the majority of the mandibular teeth so that the temporomandibular joint is resting and relaxed. Since the proper occlusal plane had been determined by the orientation of the maxillary splint  450  to the maxilla using the analyzer  200 , the flat side  452  of the maxillary splint  450  demarcates the proper occlusal plane and the proper orientation of the flat side  552  of the mandibular splint  550  in the jaw. Therefore, when the splints  450 ,  550  are used together, the splints  450  and  550  ensure that a majority of teeth will be in contact with each other when the jaw is closed, thereby lessening the burden placed on the temporomandibular joints and relaxing the elevator and positioning muscles. The maxillary splint  450  and the mandibular splint  550 .are best used together, but may be used alone as individual pieces.  
         [0037]     The method for making dental splints includes creating the maxillary splint  450  in situ on the maxilla of the patient and creating the mandibular splint  550  in situ on the mandible of the patient. First the maxillary plane analyzer  200  is prepared by joining the holding plate  300  to the lever  215 . The maxillary stent frame  400  with uncured dental acrylic in the trough is placed on the holding plate  300 . The maxillary stent  400  is then oriented on the patient&#39;s maxilla at the proper occlusal plane using the maxillary plane analyzer  200 . The uncured acrylic disposed in the trough side  410  of the maxillary stent  400  is cured in place on a patient&#39;s maxilla to take the impression from the teeth. The maxillary stent  400  is then removed from the maxilla and finished by removing the cleats  420  and smoothing off any sharp edges to create the maxillary splint  450 .  
         [0038]     Next, the mandibular stent  500  is placed on the mandible and cured in situ based on the orientation of the mandibular stent  500  to the patient&#39;s occlusal plane as demarcated by the flat surface  452  of the maxillary splint  450 . The maxillary splint  450  is replaced on the maxilla before the mandibular stent  500 , having a quantity of uncured dental acrylic in the trough side  512 , is oriented on the patient&#39;s mandibular teeth. Finally, the acrylic in the trough side  512  is cured in place on the mandible to the shape of the mandibular teeth, thereby forming the mandibular splint  550 . As with the maxillary splint  450 , the mandibular splint  550  is finished by smoothing out rough edges.  
         [0039]     It is to be understood that the present invention is not limited to the embodiment described above, but encompasses any and all embodiments within the scope of the following claims.