Comparison of sagittal and transverse condylar inclination measurement techniques in virtual articulator programming: a technical report.

OBJECTIVES

This technical evaluation aimed to compare 5 techniques for measuring sagittal (SCI) and transverse condylar inclination (TCI) to optimize virtual articulator programming in digital dentistry.

METHODS

14 healthy participants (7 males, 7 females; aged 18-25 years) with 28 temporomandibular joints were evaluated. A novel virtual facebow system was developed to assess 5 measurement approaches based on natural head position (NHP) with horizontal plane markers: (1) Adjustable articulator (AAG); (2) Facial/intraoral scan integration (FIG); (3) CBCT/intraoral scan fusion (CIG); (4) Direct CBCT measurement (CTG), and (5) Kinematic facebow with T-Scan analysis (KFG). Triplicate measurements of interocclusal, protrusive, and lateral records were averaged. Statistical analysis included paired t-tests for bilateral comparisons and repeated measures ANOVA with Bonferroni-Greenhouse-Geisser corrections for technique comparisons.

RESULTS

No significant differences were observed between left and right condylar inclination values (P > 0.05). Significant differences were detected among the measurement techniques for both SCI and TCI values (P < 0.001). Specifically, for SCI, KFG (41.81 ± 13.92°), CIG (43.05 ± 13.38°), and FIG (43.60 ± 12.64°) showed similar results (P > 0.05), while CTG (47.52 ± 9.12°) produced significantly higher values than AAG (37.68 ± 9.75°) (P < 0.05). For TCI, KFG (12.58 ± 7.27°), FIG (13.91 ± 7.72°), and CIG (11.85 ± 8.14°) again demonstrated similarity (P > 0.05), whereas both CTG (18.57 ± 8.75°) and AAG (19.50 ± 6.33°) yielded significantly higher values (P < 0.05).

CONCLUSIONS

Digital workflows based on natural head position with horizontal plane markers-integrating facial, intraoral, and cone beam computed tomography data-achieve sagittal and transverse condylar inclination values comparable to kinematic facebow recordings, supporting their use as reliable alternatives for virtual articulator programming.

CLINICAL SIGNIFICANCE: Integrated natural head position‑based digital protocols provide efficient, clinically valid solutions for condylar inclination assessment, supporting the transition to digital prosthodontic workflows.