Investigation of bifid mandibular canal frequency with cone beam computed tomography in a Turkish population

Abstract

Objectives: It is important to know anatomic location and variations of the mandibular canal (MC) for surgical treatment on mandible such as implant operations, impacted molar tooth extraction and sagittal split ramus osteotomy. The purpose of our study is to determine the configuration and incidence of bifid mandibular canal (BMC) using cone beam computed tomography (CBCT).

Methods: CBCT scans of 2000 patients were retrospectively analysed. Age and gender of the  patients who were included in this study were recorded. BMC was subdivided, frequency was determined. Measurements of mean lengths, superior and inferior angles were performed. The all measurements were performed by one observer in 3 times at intervals of one week to confirm intra-observer reliability. SPSS 21 (Statistical Package for Social Science 21) was used for statistical analysis. It was benefited from Chi-square test to investigate qualitative observation and from T test and one-way analysis of variance for investigation of quantative observation. Differences were considered significant at p<0.05.

Results: 1122 of 2000 patients (56.1%) were females and 878 of 2000 patients (43.9%) were males. BMC was observed in 61 of 2000 patients (3.05%). Because location of MC is bilateral, 122 sides in 61 patients were studied. BMC was observed in 65 of 122 sides (53.3%). In 39 of 65 sides (60%), BMC was observed in males, in 26 of 65 (40%) sides, BMC was observed in females.

Conclusion: CBCT provides important informations about MC imaging and evaluation of variations. Evaluation of MC variations frequency and informing to surgeon in surgical procedures on mandible provides advantages for successful operations.

Keywords

• anatomy
• bifurcation
• cone beam computed tomography
• mandibular canal

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