Marco Aurélio Versiani1, Ronald Ordinola-Zapata2, Ali Keleş3, Hatice Alcin3, Clóvis Monteiro Bramante2, Jesus Djalma Pécora4, Manoel Damião Sousa-Neto4. 1. Department of Restorative Dentistry, Faculty of Dentistry, University of São Paulo, Av do Café s/n, Bairro Monte Alegre, CEP 14049-904 Ribeirão Preto, SP, Brazil. Electronic address: marcoversiani@yahoo.com. 2. Department of Endodontics, Bauru Dental School, University of São Paulo, Av. Octávio Pinheiro Brisola 9-75, Vila Universitária, CEP 17012-901 Bauru, SP, Brazil. 3. Department of Endodontics, Faculty of Dentistry, Ondokuz Mayıs Üniversitesi, 55139 Kurupelit-Samsun, Turkey. 4. Department of Restorative Dentistry, Faculty of Dentistry, University of São Paulo, Av do Café s/n, Bairro Monte Alegre, CEP 14049-904 Ribeirão Preto, SP, Brazil.
Abstract
OBJECTIVE: To describe the morphological aspects of middle mesial canals (MMC) in mandibular first molars using micro-CT. DESIGN: Mandibular first molars collected from the Brazilian (n=136) and Turkish (n=122) populations were scanned (voxel size: 9.9μm) and mesial roots with MMC (n=48) evaluated regarding several morphological aspects. The incidence of MMC in each population was statistically compared using Chi-square test (α=0.05). RESULTS: Overall, the incidence of MMC was 18.6% (48 out of 258 molars) and was significantly higher in the Brazilian (n=30; 22.1%) than in the Turkish (n=18; 14.8%) population (p<0.05). In both populations, confluent configuration of the MMC was the most frequent anatomy. Most of the specimens with MMC had 3 independent orifices (n=26; 54.2%) and 3 apical foramina (n=21; 43.8%). The mean minor diameter of the MMC orifice (0.16mm) was 3 times less than the other orifices (∼0.50mm). In mesial roots with independent configuration (n=3; 6.3%), the mean volumes (mm(3)) of the MMC, mesiobuccal (MBC) and mesiolingual (MLC) canals were 0.20±0.10, 0.75±0.28, and 0.88±0.19, respectively. In the specimens with canal confluence (n=26; 54.2%), MMC merged to the MBC (n=8; 16.7%), MLC (n=4; 8.3%), or to both MBC and MLC (n=14; 29.2%). Double mesial canal was observed in only 1 specimen. MMC with an independent foramen was observed mostly in Brazilian specimens. CONCLUSIONS: Incidence of MMC was higher in the Brazilian molars. Confluent configuration was the most prevalent anatomic variation, while independent and fin configurations, as well as, double MMC, were found only in a few specimens.
OBJECTIVE: To describe the morphological aspects of middle mesial canals (MMC) in mandibular first molars using micro-CT. DESIGN: Mandibular first molars collected from the Brazilian (n=136) and Turkish (n=122) populations were scanned (voxel size: 9.9μm) and mesial roots with MMC (n=48) evaluated regarding several morphological aspects. The incidence of MMC in each population was statistically compared using Chi-square test (α=0.05). RESULTS: Overall, the incidence of MMC was 18.6% (48 out of 258 molars) and was significantly higher in the Brazilian (n=30; 22.1%) than in the Turkish (n=18; 14.8%) population (p<0.05). In both populations, confluent configuration of the MMC was the most frequent anatomy. Most of the specimens with MMC had 3 independent orifices (n=26; 54.2%) and 3 apical foramina (n=21; 43.8%). The mean minor diameter of the MMC orifice (0.16mm) was 3 times less than the other orifices (∼0.50mm). In mesial roots with independent configuration (n=3; 6.3%), the mean volumes (mm(3)) of the MMC, mesiobuccal (MBC) and mesiolingual (MLC) canals were 0.20±0.10, 0.75±0.28, and 0.88±0.19, respectively. In the specimens with canal confluence (n=26; 54.2%), MMC merged to the MBC (n=8; 16.7%), MLC (n=4; 8.3%), or to both MBC and MLC (n=14; 29.2%). Double mesial canal was observed in only 1 specimen. MMC with an independent foramen was observed mostly in Brazilian specimens. CONCLUSIONS: Incidence of MMC was higher in the Brazilian molars. Confluent configuration was the most prevalent anatomic variation, while independent and fin configurations, as well as, double MMC, were found only in a few specimens.