Effect of Troughing on the Identification of the Second Mesiobuccal Canals With and Without Calcifications in Maxillary First Molars

This study tested the impact of troughing on the detection rates of MB2 canals with and without calcifications. Traditional access cavities were prepared and the detection of MB2 canals was recorded in 200 maxillary molars selected based on micro-CT scans. In specimens, the MB2 orifice was not detected; troughing was performed. The number of negotiated MB2 with and without troughing was compared with micro-CT using McNemar's test. After traditional access cavity preparation without troughing, the operator detected MB2 in 142 specimens (82%). Troughing of the remaining specimens led to the further identification of 16 MB2 canals, increasing detection rate to 91%. Troughing significantly improved the detection rate of non-calcified MB2s (p < 0.05) but did not significantly impact the detection of calcified MB2 canals (p > 0.05). While troughing is highly effective in enhancing MB2 canal detection in non-calcified canals, it may be limited in cases where calcification is present.