Aminabadi Naser A, Farahani Ramin M Z, Gajan Esrafil B
Department of Pediatric Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
J Oral Sci. 2008 Mar;50(1):69-74. doi: 10.2334/josnusd.50.69.
The aim of the present study was to provide a general scheme for pulpectomy of primary molars that may be useful for decision-making about negotiation of root canals and selection of appropriate instruments. A total of 160 vital primary molars in 85 patients (40 males, 45 females) aged 4-6 years were selected. After taking primary radiographs, local anesthesia was induced, and the teeth were isolated using a rubber dam. Canal accessibility index (CAI) and tooth accessibility index (TAI) were calculated according to initial file size. Mandibular first molars had either three canals (79.2%) or four canals (20.8%), and all second molars had four canals. Maxillary first molars had three canals and second molars had either three canals (70.9%) or four canals (29.1%). Lower accessibility of the mandibular first molar distobuccal root accounted for the lower accessibility of these teeth in comparison with mandibular second molars. While three-canal maxillary second molars were more accessible due to the lower accessibility of the distobuccal canal of the maxillary first molar, poor accessibility of the distal canal in four-canal second molars was responsible for the difficult accessibility of these teeth. In conclusion, it seems that the accessibility of a single canal in each tooth determines the difficulty of accessibility for any given tooth. Moreover, while primary second molars are more accessible than first molars, all of them are negotiable.
本研究的目的是提供一个乳牙牙髓摘除术的总体方案,这可能有助于根管疏通的决策以及合适器械的选择。共选取了85例年龄在4至6岁的患者(40名男性,45名女性)的160颗活髓乳牙。拍摄初诊X光片后,进行局部麻醉,并用橡皮障隔离患牙。根据初始锉的大小计算根管通畅指数(CAI)和牙齿通畅指数(TAI)。下颌第一磨牙有三根根管(79.2%)或四根根管(20.8%),所有第二磨牙均有四根根管。上颌第一磨牙有三根根管,上颌第二磨牙有三根根管(70.9%)或四根根管(29.1%)。下颌第一磨牙远中颊根的通畅性较低,导致与下颌第二磨牙相比,这些牙齿的通畅性较差。虽然由于上颌第一磨牙远中颊根管的通畅性较低,三根根管的上颌第二磨牙更容易疏通,但四根根管的第二磨牙远中根管通畅性差导致这些牙齿难以疏通。总之,似乎每颗牙齿单个根管的通畅性决定了任何给定牙齿的疏通难度。此外,虽然乳牙第二磨牙比第一磨牙更容易疏通,但所有这些牙齿都是可以疏通的。