Koivisto Tyler, Chiona Daphne, Milroy Laura L, McClanahan Scott B, Ahmad Mansur, Bowles Walter R
US Navy Dental Corps, Camp Lejeune, Jacksonville, North Carolina.
Private Practice, Athens, Greece.
J Endod. 2016 Jul;42(7):1018-21. doi: 10.1016/j.joen.2016.03.004. Epub 2016 May 11.
The increased use of implants and potential endodontic misadventures can lead to nerve damage. The purpose of this study was to use cone-beam computed tomography (CBCT) measurements to investigate mandibular canal (MC) location in relation to mandibular posterior teeth, the dimension of the buccal and lingual bone over the MC, the diameter of the MC, and the anterior loop location near the mental foramen.
CBCT scans from 106 patients (age, 18-69 years) were used to evaluate measurements from 636 teeth and respective MC areas.
Respective locations of MC to teeth (buccal, inferior, or lingual) were as follows: second molar (57% buccal, 40% inferior, and 3% lingual), first molar (18% buccal, 55% inferior, and 27% lingual), and second premolar (33% buccal, 55% inferior, and 11% lingual). Buccal bone thickness over the MC was thickest at mesial root of second molars and thinnest over the second premolar (5.4 versus 2.6 mm). The lingual bone next to the MC was thickest over the second premolar and thinnest at distal root of first molars (3.8 versus 1.7 mm). The average diameter of the MC along the length of the canal from second molar to second premolar was 3.03 mm on left and 2.91 mm on right. The anterior loop was present in 10.4% of patients, with the average depth below bone of 13.43 mm. The anterior loop was more often seen on the left side than right and occurred bilaterally 50% of the time.
Mandibular bone thickness, nerve location, and dimension data all contribute to a useful knowledge base for practitioners. The application of CBCT imaging techniques aids in the surgical treatment, while offering advantages over conventional periapical and panoramic films.
种植体使用的增加以及潜在的牙髓治疗意外情况可能导致神经损伤。本研究的目的是使用锥形束计算机断层扫描（CBCT）测量来研究下颌管（MC）相对于下颌后牙的位置、MC上方颊侧和舌侧骨的尺寸、MC的直径以及颏孔附近前襻的位置。
使用106例患者（年龄18 - 69岁）的CBCT扫描来评估636颗牙齿及相应MC区域的测量值。
MC相对于牙齿的各自位置（颊侧、下方或舌侧）如下：第二磨牙（57%颊侧、40%下方、3%舌侧），第一磨牙（18%颊侧、55%下方、27%舌侧），第二前磨牙（33%颊侧、55%下方、11%舌侧）。MC上方的颊侧骨厚度在第二磨牙近中根处最厚，在第二前磨牙处最薄（5.4对2.6毫米）。MC旁边的舌侧骨在第二前磨牙处最厚，在第一磨牙远中根处最薄（3.8对1.7毫米）。从第二磨牙到第二前磨牙沿根管长度的MC平均直径左侧为3.03毫米，右侧为2.91毫米。10.4%的患者存在前襻，其平均低于骨面的深度为13.43毫米。前襻在左侧比右侧更常见，双侧出现的时间占50%。
下颌骨厚度、神经位置和尺寸数据都为从业者提供了有用的知识库。CBCT成像技术的应用有助于手术治疗，同时比传统根尖片和全景片具有优势。
