Veterinary Dentistry Today

A 4 year old cavalier king charles spaniel was diagnosed with TMJ luxation.



Look at this image and consider the most likely direction of luxation.  Which side is luxated?


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    Rostral and dorsal luxation is the most common. This patient has right TMJ luxation.  Caudal and ventral is much less common.


What is a common method for reduction?

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    A dowel, generally a wooden pencil with a hexagonal cross-section, is placed between the maxillary fourth premolar and mandibular first molar teeth and the mouth is closed gently over the pencil, allowing the condyle to move ventral to the mandibular fossa.


Name some treatment options for this patient to prevent the TMJ from re-luxating.

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    Maxillomandibular fixation (MMF).


    Molds were cut initially for this patient utilizing 3 cc syringe cases, which were too wide allowing composite to leak around the syringes.  Suction tubing proved to be a viable choice for the mold in this patient as shown here.  Canine teeth were etched on the palatal and lingual surface following cleaning and flower pumice.  The entire tooth was then coated with a bonding agent and light cured.  The device is left on for two weeks to allow adequate soft tissue healing but not too long for significant atrophy, fibrosis and possible ankylosis.

    Some feel a tape muzzle may be helpful instead of MMF since it allows for some joint movement while allowing the joint capsule and ligaments to stabilize.  This was not successful in this patient requiring MMF.  There was concern with the broad tongue in this breed that MMF would create a problem with tongue protrusion when lapping gruel consequently the splints were created to allow for that, opening the mouth a bit wider than usual.  Swallowing is better facilitated when the  final mouth position is less open.

    Removal of the device was accomplished with various burs and polishing discs to finish.