The elusive retromolar foramen and retromolar canal: A CBCT study

This study aims to evaluate the presence of retromolar foramen (RMF) and retromolar canal (RMC) in the mandible using cone beam computed tomography (CBCT) in Chhattishgarh population and to correlate its possible clinical impact. 175 CBCT images were collected from which 100 bilateral CBCT images of patients were retrospectively selected from the Department of Oral Medicine and Radiology of the Chhattishgarh Dental College and Research Institute and evaluated bilaterally which were taken for diagnostic purposes from maxillofacial radiology clinic and data were statistically analyzed. This was an observational descriptive study and all the images were processed and analyzed on CS3D imaging software. The data was analyzed using chi square test. The prevalence of RMF and RMC was observed in 8.5%, of which 10 were in females and 7 in males. The RMCs traversed in different directions – horizontal, vertical and angular. Based on the subjective assessment, each of these canals was further subclassified into straight and curved canal. In the present study in 12 of the cases angular curved type was found and in 3 cases, vertical straight was noticed. The bifurcation of the inferior alveolar nerve (IAN) canal was observed in 15% of the scans and remaining 85% had single mandibular canal. The proximity of RMF from buccal and lingual cortical plates was found buccally in 16 cases and in single case was found to be lingually. Position of RMF might change with the presence and absence of third molar. The absence of third molar results in anteriorly located RMF. In majority of cases it was found that RMF was located more buccal than lingual. The parameters considered in the current study will guide the oral and maxillofacial surgeons while giving incisions in 3molar impacted cases, other pathologies and ease to preserve the retromolar foramen.