The variation in the number of roots and canals morphology of permanent mandibular first molar teeth by using cone beam computed tomography imaging in a sample of Erbil city

Abstract

Background and Objectives: Adequate knowledge about the number of roots, canals, and morphology of lower first molar teeth is a basic requirement of root canal therapy and any surgical treatment in this region, was carried out to investigate root and canal morphology of permanent mandibular first molars in a sample from Erbil population using cone beam computed tomography (CBCT). Methods: This study carried out during a period from October 2017 till June 2018. The sample selected from patients visited (college of Dentistry, Denta Plus, Hollywood Smile Design) centers in Erbil city according to specific criteria. One hundred patients have been selected from those patients who referred to obtain CBCT for the lower mandibular region, after obtaining consent from these patients and about 141 mandibular first molar teeth were used in this study. Different measurements were done on the CBCT of each patient by investigating the root numbers, the number of canals and root canal configuration which classified by using Wein’s and Vertucci’s classification. The data were analyzed statistically by Pearson’s Chi-square. Results: The result indicated that the first molar tooth had two roots one mesial and one distal, while about the numbers of extra roots the result indicated that only the distal root showed five extra roots (3.5%). The data analysis for the number of canals in study sample indicated that the mesial root had two canals in all sample while in distal root showed that 41 mandibular first molars showed two canals which were about 29.1% and 100 mandibular first molars showed one canal which was about 70.9%. The result indicated that morphology of distal root canal of mandibular first molars according to Wein’s classification, it that 70.9% of the study sample was of type I morphology, both type II and type IV were about 5% of the sample, type III morphology about 12.8%, and about 6.4% of study sample classified according to Vertucci classification which showed type III morphology while for the morphology of mesial root canal of lower first molar tooth the result indicated that 100% of the samples had type III Wein’s morphology. Conclusion: The prevalence of extra root was about 3.5% in distal root. Wein’s type I the most prevalent configurations in distal root and type III Wein’s in the mesial root of the first mandibular molars. CBCT analysis of root canal system provides information and details which is very helpful in different treatment modalities.