Research progress on the middle mesial root canal in the mandibular molar / 口腔疾病防治

@#Of the various root canal morphologies in mandibular molars, the middle mesial root canal is located between the mesiobuccal root canal and the mesiolingual root canal. The middle mesial root canal is a partial or completely independent extra root canal. Because of its fine structure, concealment and even calcification of the root canal orifice, it is difficult to completely clean and fill this root canal and it is easily omitted by dentists. The current study reviewed recent progress in terms of the incidence rate, classification, influencing factors, and exploration and preparation techniques of the middle mesial root canal of the human mandibular molar to provide a reference for clinical diagnoses and treatment.

Asymmetry in mesial root number and morphology in mandibular second molars: a case report

Ambiguity in the root morphology of the mandibular second molars is quite common. The most common root canal configuration is 2 roots and 3 canals, nonetheless other possibilities may still exist. The presence of accessory roots is an interesting example of anatomic root variation. While the presence of radix entomolaris or radix paramolaris is regarded as a typical clinical finding of a three-rooted mandibular second permanent molar, the occurrence of an additional mesial root is rather uncommon and represents a possibility of deviation from the regular norms. This case report describes successful endodontic management of a three-rooted mandibular second molar presenting with an unusual accessory mesial root, which was identified with the aid of multiangled radiographs and cone-beam computed tomography imaging. This article also discusses the prevalence, etiology, morphological variations, clinical approach to diagnosis, and significance of supernumerary roots in contemporary clinical dentistry.

Clinical study of the three mesial root canals of mandibular first molars / 实用口腔医学杂志

Objective:To investigate the clinical incidence of the three mesial root canals of mandibular first molars. Methods: Incidence and morphology of the three mesial root canals of mandibular first molars were determined by probing the fissure or grooves between the mesiobuccal and mesiolingual root canal orifices and X-ray analysis. Results: Of the 222 mandibular first molars, 13 of the molars had three mesial root canals. The incidence rate was 5.85 %. Conclusion: Although the incidence rate of the three mesial root canals of mandibular first molars was very low, the dental operative microscope was helpful for the diagnosis.