First permanent molar root canal configurations in a South African sample: a descriptive micro-computed tomographic report

The aim of this paper was to describe root canal configurations using micro-CT in South African first molars. A segmentation process was followed on micro-focus X-ray computed tomography (micro-CT) scans of 101 maxillary and 86 mandibular first molars. Main and accessory root canal anatomy were considered to describe root canal configurations of South African first molars. Intra- and inter-observer reliability was determined using the unweighted Cohen’s Kappa test. Intra- and inter-rater agreement was 93% for maxillary configurations; 92.9% and 86.2% respectively for mandibular configurations. The most common main canal configurations were: 3MXFM MB1DB1P1 (n = 33/93, 35.5%) and 2MDFM M1-2D1 (n = 8/84, 9.5%) (separate three-rooted maxillary and two-rooted mandibular respectively). The addition of accessory canals resulted in configurations that were mostly individualised with only a few notable similarities. A total of 97 unique configurations were found in maxillary teeth and 85 in mandibular teeth. In the separate three-rooted maxillary molars, the only similarities were 3MXFM MB1(A2) DB1(A1) P1 (n = 4/93, 4.3%) and 3MXFM MB1(A1) DB1(A1) P1 (n = 2/93, 2.2%). In two-rooted mandibular molars, only 2MDFM M1D1 (n = 2/84, 2.4%) was noted. Root canal configurations were found to be diverse and complex.