Anatomic considerations during placement of mandibular retromolar miniplates for orthodontic anchorage – A study of the characteristics of retromolar fossa

Abstract

Objectives: The mandibular retromolar area offers a novel site for orthodontic skeletal anchorage. It houses the retromolar foramen (RMF), and surgical interventions in this area can lead to undesirable outcomes. This study aims to assess the characteristics of the RMF and its relation to the occlusal plane (OP) using cone-beam computed tomography (CBCT) data. Material and Methods: This cross-sectional observational in vitro study involved the analysis of CBCT data from 136 samples (68 males and 68 females) within the age range of 18–40 years. The study focused on factors such as the presence or absence of the RMF, whether it was unilateral or bilateral, the number of foramina on each side, and the distance of the RMF from the OP. Data analysis was conducted using the Statistical Package for the Social Sciences software, with P < 0.05 deemed statistically significant at a 95% confidence level. Results: About 39% of the sample showed the presence of RMF. The prevalence of unilateral RMF was higher than that of bilateral RMF. The mean distance of RMF above the OP was 5.99 mm, and that below the OP was 3.82 mm. Conclusion: The high prevalence (39%) of RMF suggests that the retromolar fossa region should be evaluated before the placement of mini-plates. The prevalence of RMF above the OP was significantly higher than that below the OP.