international magazine of oral implantology

26 I implants1_2011 I special _ endo-implant algorithm quired due to the morphological and anatomical vari- ationsinthevolumetricsizeoftheroot-canalanatomy. Siqueiraetal.demonstratedthatregularexchangeand use of large amounts of irrigant should maintain the antibacterialeffectivenessoftheNaOClsolution,com- pensatingfortheeffectsofconcentration.28Numerous deviceshaveappearedintheendodonticarmamentar- iumtoaddressthissituation: _EndoVac (Discus Dental): a negative pressure dif- ferential device designed to deliver high volumes of irrigation solution while usingapicalnegativepressure through the office high-volume evacuationsystem; _Negative Pressure Safety Irrigator (Vista Dental): deviceissimilartoEndoVac; _Rinsendo (Air Techniques): uses pressure suction technology;65mlofirrigantareautomaticallydrawn from the attached syringe and aspirated into the canal (pressure created is lower than manual irrigation);and _Vibringe (Bisco Canada): sonic flow technology facilitates enhanced irrigation through the myriad complexitiesoftheroot-canalsystem(Fig.11). NaOCl cannot dissolve inorganic dentine particles andthuspreventsmearlayerformationduringinstru- mentation.29 Chelators,suchasEDTAandcitricacid,are recommended as adjuvants in root-canal therapy. It is probable that biofilms are detached with the use of chelators;however,theyhavelittleifanyantibacterial activity. Several studies have demonstrated that citric acid in concentrations ranging as high as 50% were more effective at solubilisation of inorganic smear layer componentsand powdereddentinethanEDTA.Inad- dition, citric acid has demonstrated antibacterial ef- fectiveness. Technologyandinnovationwillnotnegatetheneed for optimal preparation (debridement and disinfec- tion)toeliminatemicrobialcontentanditsimpactona necrotic root-canal system. We as a discipline need to improve;however,endodonticshasshownitscommit- ment to endless reinvention. In time, this will restruc- turetheroleofnaturalteethinfoundationaldentistry, currently diminished by the market forces of implant- drivendentistry. Ortho-biological replacement is not a panacea as randomclinicaltrialsincreasinglyshow;theseverityof peri-implantitis lesions demonstrates significant vari- ability and as such no treatment modality has shown superiority. The pendulum will continue to swingastheendodonticimplantalgorithm becomesincreasinglymultivariate. _Microstructuralreplica- tion—obturation StevenCoveyisknownforhis book The Seven Habits of Highly Effective People. The habit most applicable to endodontics is the second one: “begin with the end inmind”.Theimplicationofthisvi- sion with regard to idealising the final shape of the root-canal system in order to ensure that the obturation representsatotalityisprofound.Theroot canalisnegativespaceandassuchrecoveryofits originalunaffectedformisthesinequanonofobtura- tionormoredescriptively,microstructuralreplication. Perhaps the most significant example of negative spacerecoveryisMichelangelo’sstatuaryforthefuner- arychamberofPopeJuliusII.Fourunfinishedsculptures speakeloquentlytothisprocess:thefigurewasoutlined onthefrontofthemarbleblockandthenMichelangelo workedsteadilyinwardsfromthisside,inhisownwords “liberating the figure imprisoned in the marble”. This is an exacting description of debridement and instru- mentation of the root-canal space prior to root filling afteramyriadofpathologicvectorshavedestroyedthe dentalpulp,andalteredthemorphology/topographyof the system (Fig. 12). Incomplete filling of the debrided andsculptedroot-canalspaceisoneofthemajorcauses Fig. 9_Micro-etching ensures the removal of oils and debris, and the elimination of the residue in fusion lines and fissures. Routine dentine bonding is then performed. The composite selected in this instance is PermaFlo Purple (Ultradent Products, Inc.), which enables differentiation of restoration and tooth structure should re-entry be necessary. Fig. 10_There is a vast array of equipment on the market to optimise irrigation protocols. Radical change may well be in the offing; however, research and development on bio-active obturating materials may prove to be the defining variable in total asepsis. Fig. 9 Fig. 10