Regional 3D superimposition to assess temporomandibular joint condylar morphology

Abstract

Objectives: To investigate the reliability of regional three-dimensional registration and superimposition methods for assessment of temporomandibular joint condylar morphology across subjects and longitudinally. Methods: The sample consisted of cone beam CT scans of 36 patients. The across-subject comparisons included 12 controls, mean age 41.3 ± 12.0 years, and 12 patients with temporomandibular joint osteoarthritis, mean age 41.3 ± 14.7 years. The individual longitudinal assessments included 12 patients with temporomandibular joint osteoarthritis, mean age 37.8 ± 16.7 years, followed up at pre-operative jaw surgery, immediately after and one-year post-operative. Surface models of all condyles were constructed from the cone beam CT scans. Two previously calibrated observers independently performed all registration methods. A landmark-based approach was used for the registration of across-subject condylar models, and temporomandibular joint osteoarthritis vs control group differences were computed with shape analysis. A voxel-based approach was used for registration of longitudinal scans calculated x, y, z degrees of freedom for translation and rotation. Two-way random intraclass correlation coefficients tested the interobserver reliability. Results: Statistically significant differences between the control group and the osteoarthritis group were consistently located on the lateral and medial poles for both observers. The interobserver differences were #0.2 mm. For individual longitudinal comparisons, the mean interobserver differences were #0.6 mm in translation errors and 1.2°in rotation errors, with excellent reliability (intraclass correlation coefficient .0.75). Conclusions: Condylar registration for across-subjects and longitudinal assessments is reliable and can be used to quantify subtle bony differences in the three-dimensional condylar morphology.

3D osteoarthritic changes in TMJ condylar morphology correlates with specific systemic and local biomarkers of disease

“…Twenty-five surface points were selected on each condyle by one observer at corresponding (homologous) areas to closely approximate the various anatomic regions of all individuals who present marked morphological variability: 4 points evenly spaced along the superior surface of the sigmoid notch, 4 on the medial and lateral portions of the ramus adjacent to the sigmoid notch, 3 along the posterior neck of the condyle, 3 on the medial and 3 on the lateral portion of the condylar neck, and on the medial, lateral, anterior, and posterior extremes of the condylar head (Figure 2A). 18 …”

Temporomandibular joint diagnostics using CBCT

“…92 The reliability of regional 3D registration and superimposition methods for the assessment of mandibular condyle morphology, across subjects and longitudinally, has been found to be acceptable. 93 The authors claim that subtle bony differences in 3D condylar morphology can be quantified. The method was applied to assess changes in condylar 3D morphology in patients who underwent maxillomandibular advancement with and without simultaneous disc repositioning.…”

Comparison and reproducibility of 2 regions of reference for maxillary regional registration with cone-beam computed tomography

“…Based on the cranial base registrations, it is possible to quantify the skeletal displacements of both the maxilla and mandible relative to the anterior cranial base used as a stable reference structure. Recently, Schilling et al 15 suggested a regional superimposition method to assess dental changes and subtle bone remodeling within the mandible that considers the symphysis as a stable reference structure. To date, no study in the literature described the 3D voxel-based regional superimposition method for the maxilla.…”