Long-term effect of bilateral anterior elevation of occlusion on the temporomandibular joints

Oral Dis. 2022 Oct;28(7):1911-1920. doi: 10.1111/odi.13914. Epub 2021 May 30.

Abstract

Objective: Incisors tubed prosthesis with bilateral anterior elevation (BAE) relation had been reported to stimulate the proliferative response in the mandibular condylar cartilage of mice, thus the prosthetic occlusion elevation had been proposed to treat cartilage degeneration. Currently, we aimed to detect the long-term effect of BAE on temporomandibular joints (TMJs).

Materials and methods: Twelve 6-week-old female mice were assigned to age-matched control and BAE groups (n = 6). Micro-CT images and the macro- and micro-morphology of the mandibular condyles were analyzed at 29 weeks.

Results: Compared with the age-matched controls, in BAE group, there were loss of subchondral cortical bone and heavy loss of the subchondral trabecular bone at the superior sites of the TMJ condyles, but hyperostosis at the inferior sites as revealed by micro-CT images and histological slices. In BAE group, cartilage thickness and matrix area were increased with upregulated expression of type II, type X collagen, and Ki67, but the expression of cleaved caspase-3 was downregulated (all, p < 0.05).

Conclusion: In addition to cartilage thickening, long-term BAE induces loss of the subchondral cortical bone and heavy loss of the underneath subchondral trabecular bone, but hyperostosis further underneath. Using BAE as a treatment remains double-edged.

Keywords: cartilage; occlusion; subchondral bone; temporomandibular joint.

MeSH terms

  • Animals
  • Cartilage, Articular* / diagnostic imaging
  • Cartilage, Articular* / metabolism
  • Dental Occlusion
  • Female
  • Hyperostosis* / metabolism
  • Hyperostosis* / pathology
  • Mandibular Condyle / diagnostic imaging
  • Mandibular Condyle / metabolism
  • Mice
  • Temporomandibular Joint / diagnostic imaging
  • Temporomandibular Joint / pathology
  • X-Ray Microtomography / methods