A study on volumetric change of mandibular condyles with osteoarthritis using cone-beam computed tomography

Abstract

This study aimed to quantitatively assess three-dimensional changes in the mandibular condyle with osteoarthritis using cone-beam computed tomography (CBCT). Pre- and post-treatment CBCT images of temporomandibular joints (TMJs) from 66 patients were used to assess longitudinal changes in condylar volume within individual patients using 3D slicer software. Total volume difference (dV), net increase (dV + , bone deposition), and net decrease (dV- , bone resorption) after treatment were analyzed based on clinical and radiological factors. Condyles with surface erosion at their first visit showed significantly decreased volume after treatment compared to condyles without erosion (p < 0.05). Amounts of bone resorption and deposition were higher in condyles with surface erosion (both p < 0.01). In patients with condylar erosion, the presence of joint pain was associated with a decrease in condylar volume and an increase in net resorption (both p < 0.01). When both joint pain and condylar erosion were present, patients with parafunctional habits showed reduced condylar volume after treatment (p < 0.05). Condylar volume change after treatment was negatively correlated with the duration of pain relief (R = - 0.501, p < 0.05). These results indicate that condylar erosion and TMJ pain could be significant variables affecting TMJ volume changes after treatment. Establishing appropriate treatment strategies is crucial for managing condylar erosion and TMJ pain.

Keywords: Cone-Beam computed tomography; Diagnostic X-Ray radiology; Osteoarthritis; Temporomandibular joint disorders.

Figure 1

Representative images of temporomandibular joint (TMJ) cone-beam computed tomography (CBCT) images and image processing result. Sagittal CBCT images of pre-treatment (upper row) and post-treatment (lower row) condyle from a normal subject and patients with degenerative joint diseases. Overlap visualizes the comparison of segments between pre- and post-treatment condylar heads. Red segment, pre-treatment; Blue segment, post-treatment. 3D overlap shows rendered models of pre- and post-treatment condyle. Red segment, pre-treatment; Blue segment, post-treatment. The images were generated using the open-source software 3D Slicer (v4.11, Slicer, http://www.slicer.org/).

Figure 2

Image processing steps. (a–b) Original cone-beam computed tomography (CBCT) images of pre- and post-treatment from the same patient. (c–d) Pre- and post-treatment CBCT images after removal of cranial parts. (e–f) Alignment of pre- and post-treatment images by voxel-based registration and segmentation. Red segment, pre-treatment; Blue segment, post-treatment. (g–h) Selection of a common volume of interest (VOI) for both mandibles. (i–j) Cropped condylar head images by the common VOI. (k–l) Resultant segments of pre- and post-treatment condylar heads. (m–n) 3D model of each segment. Red, pre-treatment (Vpre); Blue, post-treatment (Vpost). The images were generated using the open-source software 3D Slicer (v4.11, Slicer, http://www.slicer.org/).

Figure 3

Representative volumetric analysis of processed cone-beam computed tomography (CBCT) images. (a–b) Superimposition of Vpre and Vpost in sagittal and coronal view. (c–d) Sagittal and coronal views of net decrease (dV− ) and net decrease (dV +). Yellow segment, dV−  = Vpre− overlap; Green segment, dV +  = Vpost-overlap. (e–f) Anterior and posterior views of the 3D model of dV−  and dV + . The images were generated using the open-source software 3D Slicer (v4.11, Slicer, http://www.slicer.org/).