Orthosis thickness and its effect on temporomandibular joint space

The object of this study was to determine the effect of varying thicknesses of orthoses on temporomandibular (TM) joint space. The TM joint space was measured using the centric cut view of tomographic images. The measurements used selected fixed landmarks of the joint complex anatomy to find joint space. The fixed points used for the measurement of the joint space are no different than the fixed points methodology used in orthodontic cephalometric measurements. The placement of the fixed points on a radiograph is subjective. Degrees of accuracy can be accomplished with consistent use just as in the practice of cephalometric measurements. Results of such measurements do provide a relatively true record of the actual condyle and fossa relationship. The study concluded that the thickness of the orthosis moved the condyle downward and horizontally without regard to its original positioning. If clinicians know the condylar position before and after orthosis placement, a concentric position of the condyle can be established to assist in the patient's second phase treatment. Further research will prove that the physiological and anatomical balance of the temporomandibular joint complex is important in effectively managing craniofacial pain patients.