ABSTRACT
Understanding root canal morphology and anatomic variation increases the success rate in endodontic treatment and prevent iatrogenic errors. The main challenge of root canal treatment in maxillary molar is to find a mesio-buccal two (MB2) canal. The prevalence of missing canals was higher in the maxillary first molar and may cause bacterial persistence. A successful outcome can achieve with identified MB2 canal, adequate cleaning and shaping, and three-dimensional obturation in root canal irregularities. A 42-year-old male presented with loss of tooth structure and discomfort in mastication on the left maxillary posterior tooth as the main symptom. Clinical examination on #26 showed a large cavity, access opened to orifice from previous treatment, negative on vitality test, and no tenderness to percussion. Radiographic doesn’t show any abnormality on the periapical. Clinically, MB2 was located under the dentin shelf, a layer of dentin overlying the canal orifice. MB2 was removed by grooving the part of the floor in a direction away from the mesiobuccal one (MB1) orifice with an ultrasonic tip. Crown-down preparation and serial of 5.25% sodium hypochlorite combined with 17% EDTA, activated by sonic agitation as shaping and cleaning protocol. The obturation was done 10 days after intracanal medicament with warm vertical compaction technique. To increase the survival rate in endodontic treated teeth, monolithic onlay adhesively bonded to the teeth structure. Three-dimensional obturation expresses a hermetic seal in all root canal systems, which is an ultimate goal of endodontic treatment to prevent bacteria from re-entering the root canal.
