Middle Mesial Canal of the Mandibular First Molar: a case report
With increasing reports of aberrant canal morphology, the clinician needs to be aware of the possibility of having a middle mesial canal in mandibular first molars.
The purpose of this article is to report the successful treatment of a clinical case of a mandibular molar with three mesial and two distal canals.
A 47-year-old female patient was referred to the Postgraduate Specialization Course in Endodontics at the Faculty of Dental Medicine of the University of Lisbon (FMDUL), by a colleague from Oral Hygiene, to perform non-surgical endodontic retreatment in the first right lower molar.
Tooth 4.6 had a previous endodontic treatment and asymptomatic apical periodontitis. Probing was within normal depths in all surfaces except distolingual, where there was a localized pocket of 7mm.
As a treatment plan, non-surgical endodontic treatment was suggested. The treatment was performed under an operating microscope, in 4 appointments. Upon establishing access with Ultrasonic tips, three mesial canals were found. The canals were scouted with 10k and 15k stainless-steel hand files. To determine the working length, an electronic apex locator was also used.
All the canals were shaped with Reciproc files (r25, r40) (VDW, Germany) according to the manufacturer’s instructions.
Copious irrigation with 5mL syringe and a 27G notched needle with 5,25% sodium hypochlorite was done all throughout the endodontic treatment.
The canals were dried with paper points.
The root canal obturation was done with gutta-percha and resin sealer with a continuous wave of obturation technique.
A flowable composite resin was used to seal the root canal openings and the crown was subsequently restored directly with composite resin.
At 12 months, the patient is completely asymptomatic and periapical radiography shows a significant decrease in the apical lesion associated to both roots.
Root canal morphology and configuration might present the clinician with a complex anatomy requiring more diagnostic approaches, access modifications, and clinical skills to successfully localize, negotiate, disinfect, and seal the root canal system.
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