The prevalence of second canals in the mesiobuccal root of maxillary molars in a South African subpopulation : a cone beam computed tomography study

Abstract

Introduction: Endodontic therapy is a global routine dental therapeutic procedure. Despite recent and present advances in dentistry and particularly with the popularity of implant dentistry, it remains biologically and aesthetically advantageous for retention of one�s original dentition. Tooth extraction followed by surgical placement of dental implants should remain a last resort in management. Treatment success depends on intricate knowledge and a thorough understanding of the anatomy of the root canal system, in order to adequately debride, disinfect, and obturate teeth affected by irreversible pulpitis or pulp necrosis. High endodontic failure rates are frequent in the maxillary molar tooth owing to the complexity of their root canal anatomy, and variations in the number of mesiobuccal (MB) roots. Conventional radiographic imaging techniques are unreliable for the detection of multiple canals, whereas cone beam computed tomography (CBCT) has proven to be effective for visualization of additional canals of root canal systems. There is little published data on the prevalence of second canals in the MB roots (MB2) of permanent maxillary first and second molars in a South African subpopulation. The aim of this study is to detect the prevalence of MB2 canals by analysing axial views of CBCT scans of adult patients. Methodology: A total number of 200 patient CBCT scans, from 100 male and 100 female patients respectively, were enrolled in the study. A total of 800 teeth were analysed in-vivo on CBCT scans, comprising 200 right maxillary first molar teeth (tooth 16), 200 left maxillary first molar teeth (tooth 26), 200 right maxillary second molar teeth (tooth 17), and 200 left maxillary second molar teeth (tooth 27). Teeth displaying radiological evidence of an additional mesiobuccal canal (MB2) were identified. Results: First maxillary molar teeth showed a high prevalence of MB2 canals, 92% and 87%, for the 16 and 26 respectively. Second maxillary molar teeth showed a lower, but still significant, prevalence of MB2 canals, 69% and 65%, for the 17 and 27 respectively. An association between patient age, gender and the prevalence of MB2 canals was not noted in the study sample. Conclusion: Root morphology and anatomy of permanent maxillary first and second molar teeth is highly variable. The prevalence of additional canals in the MB roots is a frequent finding which has previously been underreported. The presence of these variations significantly impact endodontic therapy success, longevity, and retention of the natural dentition. The prevalence of these canals requires documentation for dissemination of this knowledge and greater cognizance thereof with respect to more accurate endodontic outcomes and success.