Evaluation of Canal Morphology at Different Levels of Root Resection inMandibular Incisors

摘要

One hundred randomly selected mandibular incisors were examined to assess theprevalence and location of two canals and to describe the canal anatomy that may be encountered during apical surgery. The roots were resected at 1, 2, and 3mm apical sections simulating a 20-degree beveled surgical resection. The sections were digitally imaged at X50 magnification and canal dimensions were measured using imaging software. The prevalence of two canals was 2% at 1mm, 0% at 2mm and 1% at 3mm. At these levels in the roots, the canal was rarely separated by hard tooth structure. An isthmus of tissue was present 20% of the time at 1mm, 30% at 2mm and 55% at 3mm. Four distinct canal types were noted: (1) round, (2) oval, (3) long oval and (4) ribbon. In 75% of the teeth, the canal shapes varied from one level to the next. The more coronally the root-end resection was made the more elongated the canal tended to become.