TMJ-CRANIOMANDIBULAR DYSFUNCTION
The Temporo-mandibular Joints (TMJ) guide or control the teeth and mandible (lower jaw) while speaking, chewing, and swallowing. Ideal orthopedic Mandibular position is termed Centric Relation Position. Centric Relation is considered the ideal orthopedic position of the Mandibular Condyle (ball) within its Glenoid Fossa (socket), maintained in an environment of health, stability, coordination and equilibrium not only of the bilateral TM Joints, but also of the entire Stomatognathic System. This System consists not only of the Mandibular Condyle and Glenoid Fossa, but of all the muscles, tendons, ligaments and osseous (bony) structures of the head and neck, as well as the teeth utilized in controlling the jaw.
There are many terms for TMJ dysfunction, which are more appropriate in defining the actual problem. Temporo-Mandibular Dysfunction (TMD) is one that is utilized, but the most appropriate term is Craniomandibular Dysfunction (CMD). This terminology is most appropriate because it captures the multitude of factors that can cause or contribute to Temporo-Mandibular Joint Disease and breakdown of the Stomatognathic System. The condition involves: failure to establish a Centric Relation Orthopedic Position of the bilateral TM Joints; failure to achieve a coordinated Mandibular Hinge Axis movement capacity; failure to establish a coordinated full Range of Motion; failure to establish a Mutually Protected Centric Occlusion of the Teeth that is in harmony with the Centric Relation Orthopedic Position of the TM Joints; failure to establish an Anterior Guidance such that the anterior teeth prevent the posterior teeth from contacting (grinding) during excursive movements of the mandible and condyle through the full Range of Motion.
Mutually Protected Centric Occlusion
Mutually Protected Centric Occlusion (MPO) requires all the back teeth to contact simultaneously with even pressure. The front teeth will be in very passive contact in this position. The vertical forces of occlusion created by pressures on the teeth as the jaw hinges fully closed should be evenly directed down the long axis of the posterior tooth roots. The posterior teeth are the molars and bicuspids. Any lateral contact forces are guided away from the posterior teeth immediately by the coupling of the upper six and lower six anterior teeth as they slide on each other during jaw movements. Due to the leverage position and the long roots of the Canines and Incisors, the back teeth are guided to separate immediately when the lower jaw moves forward or side-to-side. This protective coupling and guidance by the anterior teeth is termed the Anterior Guidance, and is the integral part of a mutually protected occlusion in centric relation. It is a departure from MPO and Centric Relation, which causes most Craniomandibular Dysfunctions.
Full Time Splint Therapy
A Maxillary Occlusal Splint is a Prosthetic Orthotic utilized to replace and mimic an ideal Occlusion of the Teeth. Just as a missing limb is replaced by a Prosthesis built to mimic as closely as possible ideal function, a Maxillary Orthotic is utilized with the same intention. The splint will be made of a hard, clear acrylic, and it will attach to the upper teeth (in most cases). Its shape is determined by the individuals own parameters of anatomy, and the need to mimic Mutually Protected Occlusion in order to eventually obtain Centric Relation of the Tempero-Mandibular Joints.
The Goal of Splint Therapy is to serve both as a therapeutic and diagnostic tool incorporating a disciplined rehabilitative therapy leading to centric relation, and the ability to accurately diagnose a course of treatment. The Maxillary Orthotic Splint will be utilized and continuously adjusted to establish and maintain a Mutually Protected Occlusion (MPO) in order to facilitate:
“The 4R’s”
- Reposition the Mandible into Centric Relation
- Rehabilitate the Joint Tissues
- Recoordinate the Mandibular Movement from CR
- Finally diagnose the appropriate procedures necessary to
Restore the Stomatognathic System.
