Comparison of the prevalence and linear measurements of the retromolar Canal on cone beam CT scans in Palestine and China.

Background: The retromolar canal (RMC) is a mandibular anatomical variation containing neurovascular structures that may impact the success of anesthesia and surgical procedures in the posterior mandible. Its prevalence varies across populations, yet no prior comparative study has assessed RMC characteristics between Chinese and Palestinian populations. This study aims to evaluate and compare the prevalence, classification, and linear measurements of RMCs in these two groups using cone beam computed tomography (CBCT).

Methods: A total of 300 bilateral CBCT scans (150 Chinese and 150 Palestinian) were retrospectively analyzed. RMCs were identified and classified according to Von Arx's system into Types A, B, and C. Linear measurements of length and diameter were taken using CBCT software. Statistical analysis included descriptive statistics, the Kolmogorov-Smirnov test for normality, independent samples t-tests, ANOVA, paired t-tests, chi-square tests, and Pearson's correlation, with significance set at p < 0.05.

Results: RMC prevalence was 22% in the Chinese group and 12% in the Palestinian group. Type B was the most common configuration in both populations. No significant differences were found regarding sex or mandibular side. Mean RMC length was slightly higher in the Chinese sample (12.02 ± 2.82 mm) compared to the Palestinian sample (10.95 ± 3.28 mm). Male participants exhibited significantly larger RMC diameters than females in both populations (p = 0.030). No significant correlation was observed between RMC presence and third molar eruption patterns (p = 0.634).

Conclusions: This study identified ethnic differences in RMC prevalence and morphology, with higher occurrence in the Chinese population. Although not associated with third molar eruption, RMC remain clinically relevant due to potential surgical and anesthetic complications. These findings underscore the importance of CBCT imaging in preoperative planning to enhance patient safety and procedural outcomes.