assessment of root morphology and apices of first and second maxillary molars in tehran population

introduction: objective: this study aimed to assess the possible variations in root canal anatomy and topography of the apices of first and second maxillary molars. materials and methods: a total of 67 first and second maxillary permanent molars were collected. access cavity was prepared and 2% methylene blue was injected. the teeth were demineralized by 5% nitric acid and cleared with methyl salicylate. specimens were evaluated under stereomicroscopy and analyzed using the sample t-test. results: based on vertucci's classification, the mesiobuccal root of maxillary first molars was type i in 87.5% and type iv in 12.5% of the cases. the mesiobuccal root of second maxillary molars was type i in 60%, type ii in 8.6%, type iv in 25.7% and type v in 5.7% of cases. in maxillary first and second molars, the distobuccal and palatal roots were type i in 100% of the cases. the distance of the apical constriction from the apical foramen was 0.21±0.09 mm, the distance from the apical constriction tothe anatomic apex was 0.44±0.19 mm and the distance of the apical foramen from the anatomic apex was 0.15±0.15 mm. the mean percentage of delta prevalence was 3.2% in both teeth. conclusion: the mean distance of the apical foramen and apical constriction from the anatomic apex was less than 0.6 and 1.2 mm, respectively. in maxillary first and second molars, the mean distance of the apical constriction from the apical foramen and anatomic apex was 0.21 and 0.44, respectively and the mean distance of the apical foramen from the anatomic apex was 0.15 mm