Journal Article

A retrospective study of remodeling changes of the temporomandibular joint structures in patients with unilateral posterior tooth loss

Zhang, Menghan, Pu, Rui, Lv, Yan, Huang, Ching-I, Zhang, Wenzhe, Wu, Mengjie, Fu, Yajing

2026

Overview

Background This study aimed to enhance understanding of how unilateral posterior tooth loss (UPTL) affects temporomandibular joint (TMJ) structures and to explore potential influencing factors on joint morphology. Methods The study included 68 subjects (34 patients with UPTL and 34 with complete dentition), divided into the missing group ( n  = 34 joint sides), the contralateral group ( n  = 34 joint sides), and the control group ( n  = 68 joint sides). Morphological measurement of the condyle, glenoid fossa and joint spaces were performed using cone-beam computed tomography (CBCT) and Mimics software. Analyses and comparisons were made among the three groups, with subgroup analyses based on the duration of tooth loss (< 1 year and ≥ 1 year), first molar loss, and the presence of unilateral chewing habit (UCH). Results Some significant differences among the control, the missing, and the contralateral groups were observed in measurements of the glenoid fossa and joint spaces ( P  < 0.05). When tooth loss lasted less than 1 year, the contralateral side exhibited significantly larger posterior joint spaces than the missing side ( P  < 0.05), whereas no differences were observed at ≥ 1 year. In the first molar loss subgroup, the anteroposterior and mediolateral diameters of the glenoid fossa were significantly larger on the contralateral side than on the missing side ( P  < 0.05). Moreover, unilateral chewers with UPTL exhibited significantly smaller anteroposterior condylar diameters on the preferred chewing side ( P  < 0.01). Conclusion An overall enlargement of both the glenoid fossa and joint spaces was observed in patients following UPTL; the glenoid fossa was found to be more susceptible to bone resorption than the condyle. Factors such as the duration of tooth loss, the absence of the first molar, and UCH contribute variably to these structural changes, indicating that different tooth-loss conditions can impose distinct biomechanical impacts on the TMJ.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Adult / Bone Remodeling / Bone resorption / Care and treatment / Chewing / Complications and side effects / Computed tomography / Cone-Beam Computed Tomography / Dentistry / Dentition / Duration of tooth loss / Edentulous / Female / First molar / Humans / Male / Mandibular Condyle - diagnostic imaging / Mandibular Condyle - pathology / Mastication / Medical research / Medicine / Medicine, Experimental / Middle Aged / Molar / Morphology / Oral and Maxillofacial Surgery / Retrospective Studies / Risk factors / Root resorption / Teeth / Temporomandibular joint / Temporomandibular joint (TMJ) / Temporomandibular Joint - diagnostic imaging / Temporomandibular Joint - pathology / Temporomandibular Joint - physiopathology / Temporomandibular joint disorders / Three-dimensional analysis (3D) / Tooth loss / Tooth Loss - pathology / Tooth Loss - physiopathology / Unilateral chewing habit (UCH) / Unilateral posterior tooth loss (UPTL)