The anterior open bite type case is among one of four main category type problems of TMJ dysfunction that most TMJ experts and neuromuscular dentist stuggle with while attempting to resolve and stabilize the masticatory pain dysfunction syndrome.
4 Categories of Dysfunctional Mal Occlusion
- Cervical Dysfunction
- TMJ Primary
- Class II division 2
- Anterior open bite
Since there is no overlap and proper overjet of the maxillary anterior teeth as in the dental Class I relationship, the movements and positioning of the lower jaw must accommodate to the abnormal swallowing, chewing, speaking and resting patterns of the the unsupported musculature.
The maxillary and lateral incisors play a very important role to assist the muscles to move precisely about and around each of the opposing lower incisors and cuspids which nature designed to prevent the posterior bicuspids and molars from excessively rubbing and grinding together. Chronic occlusal contacting of the posterior teeth in the anterior open bite type case can further give rise to clenching as well as induce strain and torque to the mandible resulting in muscles fatigue of the jaw.
The upper and lower incisors are designed to lift and help separate the posterior bicuspids and molars during all lateral and protrusive movements of the lower jaw (mandible). The cuspids (canines) are designed to also help create a gliding movement as well as lift of the posterior teeth during lateral side movements to avoid excessive muscle strain to the corner of the mandible, facial region, temporal, back of the head and neck and shoulder regions. When posterior teeth chronically rub and contact one another it sets up a cascade of symptoms that produces strain to the zygomatic (facial) region, strain to the lower posterior corner of the mandible, strain to the sternocleidomastoid (SCM), anterior scalene as well as trapezious muscles. Because of these unrelenting torques and strains due to poor disclusion during lateral and protrusive movements of the lower jaw, the occiput, atlas (C1) and pelvis cannot maintain balance and stability. Normalized occlusal schemes is a key and a must if one desires to resolve the TMD challenges that also effect the central nervous system (CNS).
Some within the dental profession believe that occlusion does not play a role in TMJ. Others also believe that anterior tooth contact does not function during normal chewing cycles, thus “anterior guidance” or disclusion do not matter. This is far from the truth. In fact, without proper positioning and alignment of the anterior teeth the jaws can’t not properly function without continual disturbance to the central nervous system. Stability cannot be maintained. Nature designed the anterior teeth in such a manner to protect and disclude the posterior teeth. Nature designed and architected the posterior occlusion in such a manner that supports proper function of the head, neck as well as the jaw joints. All the muscles of mastication will respond in a healthy manner to normalized tooth alignment. The masticatory apparatus will respond negativelyl to abnormal demands of maligned teeth (anterior open bites) and abnormal occlusal relationships resulting in dysfunction with the many neuromuscular symptoms.
Many clinicians have tried unsuccessfully to use the classic lower removable orthotic without paying attention to the anterior disclussion. Others tried using soft splints, aqualizing type remedies, medications, upper discluders which only makes symptoms worse. Once the anterior open bite syndrome occurs and the muscles become hyperactive, further transverse narrowing of the bicuspid and molar regions occurs. A diminishing of the occlusal support mechanism is no longer present, thus the masticatory muscle cannot calm down (furthering the pain cycle). With an excentuated opening of the anterior teeth, further occlusal forces are placed on the posterior region of the jaw increasing the likelyhood for teeth sensitivity, root canal treatment and periodontal boneloss. Because there is a slow bite collapse (lingually, vertically, anterior posteriorly and transversely), the intra oral volume for the tongue is diminished subtley restricting the posterior oral pharyngeal region of the mouth and throat to naturally cause the tongue to further thrust forward preventing the anterior teeth to close vertically downward.
Orthotic Appliance Design – Phase I TMJ Stabilization
The anterior open bite problem requires a specially designed orthotic that meets the standards of normal physiologic occlusal stability and functional movements that are required to resolve the underlying muscular strains and torques to the cranium, jaw, cervical neck and shoulder regions. Gnathologic occlusal schemes is very important once an optimized and physiologic upper to lower jaw relationship has been established. Carefull attention and design must be given to the anterior region of the anterior open bite case if any appliance is to be used to effectively resolve the pain symptoms of the anterior open bite tendency type case.
© 2009 Clayton A. Chan, DDS. All Rights Reserved.