ROEN0110

I 31 case report _ failed root-canal treatment I roots1_2010 to determine a diagnosis. Such diligence can ensure that should treatment be undertaken, the patient would understand the procedure, alternatives and risks, and have his questions answered in a way that giveshimarealisticexpectationofprobablesuccessor failure. Based on this standard, it is not possible to judge the treatment as a failure and make decisions basedonthisoneimagewithoutaclinicalhistoryand subjective and objective examination. The above notwithstanding, the provided image yields significant information. The radiographic in- terpretation of this film demonstrates the following: 1. There is no coronal seal. In the endodontic litera- ture, coronal leakage is highly correlated with failure of root-canal treatment. The tooth has not been crowned nor has the pulp chamber been restored. This radiographic appearance is diag- nostic of coronal leakage. If accessed, the canals wouldalmostcertainlyshowovertevidenceofsuch leakage, manifested as odour, discoloured gutta- percha, moisture and possible purulence, amongst other signs. Microbiologically, it is virtually certain that evidence of bacterial biofilm would be located alongside the existing gutta-percha in fins, cul de sacs and other inaccessible areas of the root-canal space. 2. There is a lack of continuity in the preparation and obturation in the taper from the crown to the apex of all three roots. The coronal halves of the disto-buccal (DB), mesio-buccal (MB) and palatal canalshavegreatertaperthantheapicalhalvesdo. It appears that the prepared shape in the coronal halves was made with Gates Glidden drills. A more predictable canal shape could have been preparedusinganinstrumentliketheTwistedFile(TF; SybronEndo). For this particular tooth, TF would have prepared the palatal canal in approximately two to three insertions to a 0.10/25 after the creation of a glidepath.TheMBandDBcanals(andMB2ifpresent) could also have been prepared to a 0.08/25 in three to four insertions after the creation of a glide path. While a comprehensive discussion of TF is beyond the scope of this article, using TF in this clinical case would have provided an optimal taper with relatively few insertions and preserved root structure. It would also have minimised the possibility of vertical root fracture and strip perforation. The degree of dentine removal at the distal aspect of the MB root and the mesial aspect of the DB root indicates that the re- mainingrootwallisverythin.Whileitdoesnotappear thatastripperforationhasoccurred,theradiographic information at hand is limited and it is not possible to determine whether there is a perforation. Such excessive dentine removal is correlated with long- term risk of vertical fracture. 3. There is a radiographic lesion at the apex of the palatalroot.Itisunknownfromthisoneradiographic view whether additional lesions are present at the apexoftheMBandtheDBroots. 4.There are obturation voids in the palatal and MB root. The root-canal spaces have not been filled three-dimensionally. Such voids in obturation (aside from a lack of coronal seal) would give rise to questions about the quality of the cleaning and shaping. 5.Although not based on an empirical radiographic observation, the working length of the cleaning, shapingandobturationappearstobeappropriateas does the master apical diameter, but this may have little to do with the clinical reality, ideal true work- ing length and/or master apical diameter. _Clinical considerations Clinically, that the patient has pain—assuming that #15 is the offending tooth—would demand treatment. Treatment options in- clude extraction, root resection and root filling, or re-treatment. Part of the missing clinical history is a confirmation that #15 is the offending tooth, but it may not be. As mentioned, it is imperative that thepatienthavepercussion,palpa- tion, mobility and probing deter- mined for teeth #14 and #15 (amongst other teeth) in order to reproduce the patient’s symp- toms. Clinically, this means that thatifthereispain(forexample,in reaction to chewing in the upper left), tooth #15 would be expected Fig. 2_Twisted Files (0.12/25, 0.10/25, 0.08/25, 0.06/25, 0.04/25; SybronEndo). Fig. 2 Fig. 3 Fig. 3_Elements Obturation Unit (SybronEndo).