The Influence of Articular Eminence Morphology on Tmj Dislocations

Abstract Body: Temporomandibular joint (TMJ) dislocation is a condition in which the mandibular condyle is displaced anteriorly beyond the articular eminence. Signs and symptoms of dislocation include: (1) inability to close the mouth, (2) severe pain of the TMJ, (3) tense, spasmatic muscles of mastication. The dislocation can be unilateral or bilateral. Factors which are associated with the onset of dislocation include: trauma, certain medications and idiopathic. The influence of the articular eminence morphology on idiopathic TMJ dislocations remains in question. Previous studies about articular eminence morphology speculated that a steep slope of the articular eminence predisposing factor for TMJ dislocations, while other studies did not find such a correlation between these two variables
Objectives: The current study was designed to investigate the influence of the articular eminence morphology on TMJ dislocations.
Methods: A retrospective study of patients who were presented with idiopathic TMJ dislocation (unilateral/bilateral) and had computed tomography (CT) scan prior to surgical treatment by TMJ eminectomy, compared with patients who did not suffer from TMJ dislocations or other TMJ dysfunction and had CT scan for other medical reasons, at the department of oral and maxillofacial surgery, Hadassah Ein Kerem hospital, Jerusalem between January 2010 and January 2019.

The study included 56 temporomandibular joints: 28 joints with idiopathic dislocation in 14 patients and 28 joints without idiopathic dislocation in 14 patients. All subjects underwent CT scans which were performed in the sagittal and coronal planes.

Articular eminence morphology was classified into four types, according to the criteria set by kurita et al: box, sigmoid, flattened or deformed.

The normal value of articular eminence angle in adults has been reported to be 30-60. Articular eminences having inclination values smaller than 30 have been characterized as flat, and those having values greater than 60 have been characterized as steep.

Articular eminence was measured by: (1) height of eminence, (2) the angle of the posterior slope of the articular eminence.

The aim of this retrospective study was to investigate the relation between the height of eminence and the angle of the posterior slope of the articular eminence to idiopathic TMJ dislocation using CT scan that were performed with tools available in Dolphine3.

Results: will be completed later
Conclusion: will be completed later