Orhan Kaan, Aksoy Seçil, Bilecenoglu Burak, Sakul Bayram Ufuk, Paksoy Candan Semra
Department of Oral, Teeth and Jaw Radiology, Faculty of Dentistry, Ankara University, 06500 Besevler, Ankara, Turkey.
Surg Radiol Anat. 2011 Aug;33(6):501-7. doi: 10.1007/s00276-010-0761-y. Epub 2010 Dec 16.
Knowing the anatomic location and also variations of the mandibular canal is especially important for surgical procedures on mandible such as dental implant surgery, impacted molar extraction and sagittal split ramus osteotomy. The purpose of this study was to clarify the incidence and location of bifid mandibular canals in an adult Turkish population to avoid complications during surgical procedures.
A retrospective study using cone beam CT images was performed to evaluate bifid mandibular canal in mandible of 242 patients. Both right and left sides were studied (n = 484). Axial, sagittal, cross-sectional and panoramic images were evaluated, and three-dimensional (3D) images were also reconstructed and evaluated, as necessary. The course and length of bifid mandibular canals and the superior and inferior angles between canals were measured.
Bifid mandibular canals were observed in 225 (46.5%) of 484 sides examined. The most frequently encountered type of bifid canal was the forward canal (29.80%), followed by the retromolar (28.10%) the buccolingual (14.50%) and the dental canal type (8.30%). Mean lengths of bifid canals were 13.6 mm in the right side and 14.1 mm in the left side. Mean superior angles were 139° on the right and 141° on the left side, whereas mean inferior angles were 38° on the right side and 32° on the left side. No statistically significant differences were found in the lengths or angles between the right and left sides and also for gender (p < 0.05).
This study, which utilized CBCT images, uncovered a higher prevalence of bifid mandibular canals than what has been reported in previous studies using conventional radiography techniques.
了解下颌管的解剖位置及其变异情况，对于诸如牙种植手术、阻生磨牙拔除术和下颌支矢状劈开截骨术等下颌骨外科手术尤为重要。本研究的目的是明确成年土耳其人群中双下颌管的发生率和位置，以避免手术过程中出现并发症。
采用回顾性研究，利用锥形束CT图像评估242例患者下颌骨中的双下颌管。对左右两侧均进行了研究（n = 484）。评估了轴位、矢状位、横断面和全景图像，并在必要时重建和评估了三维（3D）图像。测量了双下颌管的走行和长度以及管之间的上下角度。
在检查的484侧中，有225侧（46.5%）观察到双下颌管。最常见的双管类型是向前管（29.80%），其次是磨牙后管（28.10%）、颊舌管（14.50%）和牙根管类型（8.30%）。右侧双管的平均长度为13.6 mm，左侧为14.1 mm。右侧平均上角为139°，左侧为141°，而右侧平均下角为38°，左侧为32°。左右两侧在长度或角度以及性别方面均未发现统计学上的显著差异（p < 0.05）。
本研究利用CBCT图像发现双下颌管的患病率高于以往使用传统放射摄影技术的研究报道。
