Frequency of accessory mental foramen and mandibular canal variations in dental implant patients: a retrospective CBCT study

Introduction
Since the first introduced use of cone beam computed tomography (CBCT) in the maxillo¬facial region it has been increasingly popular. In contrast to 2D imaging modalities such as periapical and panoramic radiographic techniques, CBCT provides some valuable information from anatomic structures and pathologies. Hence, the anatomical structures can be viewed more accurately than 2D imaging modalities. In addition, images obtained with CBCT allow for more appropriate treatment planning. The purpose of this study was to assess the accessory mental foramen (AMF) and retromolar canal which were incidentally found on CBCT images.

Objectives
The aim of this study is to reveal the frequency and characteristics of the accessory mental foramen and retromolar canal.

Material and methods
A total of 480 CBCT images obtained from dental implant patients were assessed. Demographic data and accessory mental foramen and mandibular canal variations were noted. All obtained data were analyzed using descriptive statistics.

Results
A total of 480 CBCT images were assessed. 208 (43.33%) of the patients were female and 272 (56.66%) were male. A total of 41 (8.5%) accessory mental foramen and 46 (9.6%) mandibular canal variations were discovered on 480 CBCT images. The age range of patients was from 18 to 84 years.

Conclusions
Identification of anatomical structures and their variations can play an important role in implant dentistry. Clinicians commonly prefer conventional radiologic methods to evaluate the dentomaxillofacial region. Although most of the variations are asymptomatic and require no treatment, correct identification of these findings will reduce unnecessary further diagnostic assessments and will provide more appropriate treatment plans.