Kuzekanani Maryam, Walsh Laurence J, Amiri Mousa
Endodontology Research Center, Kerman Dental School, Kerman University of Medical Sciences, Kerman, Iran.
The University of Queensland School of Dentistry, Brisbane, Australia.
Int J Dent. 2020 Oct 31;2020:8851984. doi: 10.1155/2020/8851984. eCollection 2020.
Missed additional canals are one of the most important reasons for RCT failures in molar teeth. This study aimed to determine the prevalence and distribution of middle mesial canals in mandibular first molars of the Kerman population.
A retrospective study was performed on de-identified cone beam image sets from 3 private radiology centers in Kerman. A total of 100 mandibular first molars from 62 patients (mean age 32 years) were included. Information regarding the patient's age and gender, the location of teeth, and the presence or absence of a MMC and also a second distal canal in MMC cases was recorded in an Excel table. Data were analyzed using SPSS software (IBM-USA).
The overall prevalence of MMCs in the mandibular first molars was 8.1% (10.0% in females and 6.3% in males). More cases of MMCs were seen on the right side (12.2%) than the left side (3.4%). One case of bilateral MMCs combined with bilateral second distal canals in the mandibular first molars was seen in a 26-year-old female. A further case of bilateral MMCs was found in a 32-year-old male but with single-canal distal roots on both sides.
The overall prevalence of MMCs in the Kerman population (8.1%) is at the lower end of the reported range of the international literature (0.26% to 53.8%). In the cohort examined in this study, mid mesial canals were more prevalent in females and on the right side. There was no definite relationship between MMCs and second distal canals in the mandibular first molar teeth in the same subject. MMCs may be unilateral or bilateral. Careful exploration of the pulpal floor between canal orifices is essential to prevent missing the MMC, as this would cause undesirable clinical outcomes.
遗漏额外根管是磨牙根管治疗失败的最重要原因之一。本研究旨在确定克尔曼人群下颌第一磨牙中近中中根管的患病率及分布情况。
对来自克尔曼3家私立放射中心的去识别化锥形束影像集进行回顾性研究。纳入了62例患者（平均年龄32岁）的100颗下颌第一磨牙。患者的年龄和性别、牙齿位置、是否存在近中中根管以及在存在近中中根管的病例中是否存在第二远中根管等信息被记录在Excel表格中。使用SPSS软件（美国IBM公司）进行数据分析。
下颌第一磨牙中近中中根管的总体患病率为8.1%（女性为10.0%，男性为6.3%）。右侧出现近中中根管的病例（12.2%）多于左侧（3.4%）。在一名26岁女性中发现1例双侧近中中根管合并双侧下颌第一磨牙第二远中根管的情况。在一名32岁男性中发现另一例双侧近中中根管，但两侧远中根均为单根管。
克尔曼人群中近中中根管的总体患病率（8.1%）处于国际文献报道范围（0.26%至53.8%）的下限。在本研究的队列中，近中中根管在女性和右侧更为常见。同一受试者下颌第一磨牙中近中中根管与第二远中根管之间没有明确的关系。近中中根管可能是单侧或双侧的。仔细探查根管口之间的髓室底对于防止遗漏近中中根管至关重要，因为这会导致不良的临床结果。
