Temporomandibular Disorder Signs, Occlusal Support, and Craniofacial Structure Changes Among the Elderly Vietnamese.

Abstract

The aim of study was to determine the association between signs of temporomandibular disorders (TMD), occlusal support, and alterations in the craniofacial structure of elderly Vietnamese by using cephalometric analysis. The cross-sectional study consisted of 244 participants aged 65-74years. Participants were examined for signs of TMD, including limited mouth opening, temporomandibular joint (TMJ) crepitus, TMJtenderness, and muscle tenderness. Dentition was divided into four occlusal support zones based on occluding pairs of posterior teeth by using Eichner's classification: Class A=4 support zones; Class B=1-3 support zones or only contact inanterior teeth; Class C=0 support zones. Fifteen angular and seven linear parameters were used for sagittal craniofacial skeleton analysis. 10.3% of participants had limited mouth opening, 49.6% TMJ crepitus, 16.3% TMJ tenderness, and 24.2% muscle tenderness; 45.5% had Class A occlusal support, 38.5% Class B, and 16.0% Class C. Those with Class C had significantly smaller ramus inclination, articular angle, and angles formed by the mandibular plane and shorter facial height compared to Class A and Class B (P<.001). TMD signs were significantly associated with: angles formedby mandibular plane, gonial angle, cranial base angle, effective mandibular length, and anterior facial height (P<.05). The alteration of craniofacial structures was significantly associated with TMD signs among elderly Vietnamese. The higher number of lost occlusal support zones, the more significant the changes to craniofacial structures.