ROEN0210

34 I I case report _ single-canalled teeth _Endodontic anatomy varies greatly and single- canalled teeth provide an opportunity to illustrate principlesofdiagnosisandtreatment.Inthefollowing case,apatientpresentedwithatoothache(Fig.1).The medical history was non-contributory. Diagnostic testing revealed a necrotic maxillary central incisor withsymptomaticperi-radicularperiodontitis.Evenin cases with obvious pathology, thorough endodontic diagnosisiscompletedtodeterminetheproperpulpal andperi-radicularstatusofteethintheaffectedarea, includingexaminationoftheaffectedsextantandthe opposing arch. Basedonthesefindings,Idecidedtotreatthetooth in two visits. Emphasising debridement in a crown- downfashion,thecanalsystemwasenteredandflared coronally.Avarietyofinstrumentscanbeusedforthis purpose,includingGates-Gliddendrillsasusedinthis case, followed by tapered rotary NiTi instruments. No attempt is to be made to instrument to full length until coronal flaring and preliminary disinfection are completed. The goal is to minimise the risk of pushing debristhroughtheapicalforamen.Apreliminarycanal lengthisestablished,followedbyadefinitiveworking length as treatment progresses. _Apical preparation Theapicalpreparationwassizedandfinalisedwith non-tapered rotary instruments (LSX, Discus Dental). Fig. 1_Pre-op X-ray. Fig. 2_Immediate post-op X-ray. Fig. 3_Immediate post-op X-ray. Fig. 4_X-ray at 16-month control. roots2_2010 Fig. 1 Fig. 2 Fig. 3 Principles of diagnosis and treatment Author_ Dr Kendel Garretson, USA