Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI, USA.
Dentomaxillofac Radiol. 2014;43(1):20130273. doi: 10.1259/dmfr.20130273. Epub 2013 Oct 29.
To investigate the reliability of regional three-dimensional registration and superimposition methods for assessment of temporomandibular joint condylar morphology across subjects and longitudinally.
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.
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).
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.
研究跨个体和纵向评估颞下颌关节髁突形态的区域三维配准和叠加方法的可靠性。
样本包括 36 例患者的锥形束 CT 扫描。跨个体比较包括 12 名对照者，平均年龄 41.3±12.0 岁，12 名颞下颌关节骨关节炎患者，平均年龄 41.3±14.7 岁。个体纵向评估包括 12 名颞下颌关节骨关节炎患者，平均年龄 37.8±16.7 岁，在术前颌骨手术前、术后即刻和术后 1 年进行随访。所有髁突的表面模型均由锥形束 CT 扫描构建。两名经过校准的观察者独立进行了所有配准方法。基于标志点的方法用于跨个体髁突模型的配准，使用形状分析计算颞下颌关节骨关节炎与对照组之间的差异。基于体素的方法用于计算平移和旋转的 x、y、z 自由度的纵向扫描配准。双向随机组内相关系数检验了观察者间的可靠性。
两位观察者均一致地在外侧和内侧极发现了对照组和骨关节炎组之间的统计学显著差异。观察者间差异≤0.2mm。对于个体纵向比较，平均观察者间差异在平移误差中为≤0.6mm，在旋转误差中为 1.2°，具有极好的可靠性（组内相关系数>0.75）。
用于跨个体和纵向评估的髁突配准是可靠的，可以用于量化三维髁突形态中的细微骨性差异。
