Abstract
Abstract
Objective
This study aimed to investigate the 3D Jarabak ratio and evaluate vertical skeletal patterns in adult patients using CBCT.
Materials and methods
CBCT scans of 97 pre-treatment adult patients were retrospectively selected and imported into MIMICS software. Following 3D model construction, the Jarabak ratio and FH-PP, FH-OP, and FH-MP angles were measured in three dimensions. All measurements were performed twice by two experienced examiners. Reliability and variable correlations were evaluated. Additionally, the 3D Jarabak ratio was compared among normodivergent, hyperdivergent, and hypodivergent groups, which were classified based on their 2D cephalometric FH-MP angles.
Results
High measurement reliability was confirmed, with all ICCs above 0.85 and the 3D Jarabak ratio ICCs exceeding 0.90. A significant positive correlation was observed between FH-MP and FH-OP. The 3D Jarabak ratio correlated negatively with both FH-OP and FH-MP. No significant correlation was found between FH-PP and the other variables. Group comparisons revealed a significantly larger 3D Jarabak ratio in the hypodivergent group compared to the normodivergent (P < 0.001) and hyperdivergent (P = 0.001) groups, with no significant difference between the latter two.
Conclusions
The CBCT-based 3D Jarabak ratio demonstrates sufficient reliability and effectively reflects the spatial divergence of the mandibular and occlusal planes. While this ratio effectively identifies hypodivergent skeletal patterns, it cannot clearly differentiate between normodivergent and hyperdivergent groups.
Clinical Relevance:
Integrating this 3D Jarabak ratio measurement into routine analysis provides valuable reference for vertical skeletal diagnosis, facilitating more comprehensive spatial evaluation and individualized treatment planning in adult orthodontics.