Natural root canal deviation and dentin thickness of mandibular first molars assessed by microcomputed tomography

Objective: To assess the centralization and dentin thickness of mesial root canals by microcomputed tomography (micro-CT). Methods: Ninety-nine mandibular molars Vertucci’s type IV mesial canals were scanned by micro-CT. The mesiodistal deviation; and the centroid were calculated for mesiobuccal (MB) and mesiolingual (ML) canals (apical 4 mm and full canal). Results: The centroid was deviated in MB and ML canals in full canal (MB=0.83 mm, 0.02-2.30 mm, and ML=0.83 mm, 0.05-3.99 mm), and in 4mm (MB=0.18mm,0.01-1.01 mm and ML=0.21 mm, 0.01-1.01 mm). In the full canal, both MV (69%) e ML (57%) deviated to mesial (M). In 4 mm, the deviation was M in 51% for MB canals and 52% of ML to distal (D). The dentin thickness was similar for MB and ML canals and their walls. Distal wall was lower for MB canal (0.07 mm) and M wall the higher in the MB canal (2.46 mm). Conclusions: There is no centrality of mesial canals in mandibular first molars. The M deviation was frequent in the full canal. Dentin thickness were similar between mesial canals.