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16 Endo Tribune United Kingdom Edition April 1-7, 2013 ‘As endodontists, we are specialised in the treatment of root canal systems. However sometimes we focus on this only, forgetting that there is more to a tooth than a root’ S everal reports in the lit- erature describe iatrogenic errors during root canal treatment. The most common errors include perforations, ledg- ing, transportation, zipping, over- extension, file separation and underfilling. Little emphasis is placed on the preparation of a tooth before starting root canal treatment, or on the finishing of the tooth after obturation of the root canal system. On various on- line forums and in several clinical articles, beautifully executed root canal treatments are shown with coronal restorations that are less than ideal. This is a serious prob- lem, since it has been demon- strated that a successful outcome depends not only on adequate root canal treatment, but also on ade- quate coronal restoration. In this article, I will elaborate on these aspects and present a case as an example. Before starting root canal treatment As endodontists, we are special- ised in the treatment of root canal systems. However sometimes we focus on this only, forgetting that there is more to a tooth than a root. When a patient comes into our office, often he will have (a) symptomatic apical periodonti- tis. Whether the tooth has been treated before is somewhat irrel- evant in the scope of this article. The first thing that we, as practi- tioners, should try to determine is the cause of the problem. The most cited causes are previous inadequate root canal treatment, primary decay, recurring decay, worn restorations and poor resto- rations overall. If the tooth has not undergone root canal treatment previously, then the cause of the problem is most likely one of the coronal factors. It is important to address this. After all, what is the point of performing a beautiful root canal treatment if the pri- mary cause of the problem is not treated? The best way to do this is by removing the old restoration completely, followed by full car- ies removal. This may sound logi- cal, but it is not. There are certain disadvantages with this approach, and it is these disadvantages that guide many practitioners in their decision-making. Removing an existing restoration might result in the sacrifice of healthy tissue and it might make it more difficult to obtain proper isolation with a rubber dam. Another factor is time; removing an old restoration is time-consuming and even more so if a build-up is required before endodontic treatment. These are some reasons that many practitioners choose to leave the old restoration in place. This can compromise the treat- ment outcome and is a risk that can be avoided. Fortunately, there are advantages too. By removing the old restoration and subse- quently all the caries, the practi- tioner eliminates one of the major causes of failure and can assess immediately whether the tooth is restorable and thus avoid unnec- essary treatment. Another advan- tage is that it is necessary to fabri- cate a completely new restoration afterwards, which avoids patching up of old restorations. Overall, the advantages are greater than the disadvantages and the only thing it requires from the practitioner is a change in behaviour and some perseverance. After root canal treatment Once root canal treatment has been completed, often we need to send the patient back to the referring dentist. In this case, an adequate temporary restoration must be placed. Typically, a tem- porary filling material like Cavit (3M ESPE) or a glass ionomer cement is used. A cotton pellet or some other form of space main- tainer is generally placed under- neath this temporary filling. This is done because the referring den- tist then has easier access to the pulp chamber so that he can gain better retention when placing the permanent restoration. There are several disadvan- tages to this approach. Leaving space between the temporary restoration and the canal orifices puts the patient at risk of contami- nation. As practitioners we can- not guarantee that the patient will show up for the permanent res- toration, sometimes the appoint- ment is cancelled for a variety of reasons. Another risk is fracture of the restoration and/or tooth. If that happens the gutta percha can be exposed to saliva, which too might lead to contamination. Ideally, however, the tooth should be restored immediately after the root canal treatment has been carried out. This means that the endodontist places the permanent restoration. Advantages with this approach are: • It saves the patient a visit to his regular dentist • The tooth is already isolated, creating the ideal environment for a restoration • It saves the referring dentist time, which he can spend on other treatments • It offers the endodontist some variety in the treatments he per- forms, enabling him to broaden his skill set Again, this only requires a change in behaviour of the prac- titioner and some perseverance. It will also require that the referring dentist allow the endodontist to place the restoration. The endo- dontist will have to upgrade his skills, so that he can also create beautiful coronal restorations. Following, is a case that illus- trates the advantages and disad- vantages of the above-mentioned Iatrogenic errors before and after non-surgical root canal treatment Dr Rafaël Michiels Fig 1. Diagnostic radiograph, show- ing the separated instrument in the mesiobuccal canal. Fig 2. Size 15 Flexile file passing through the perforation. Fig 3. Perforation repair with grey MTA-Angelus. Fig 4. Post-op radiograph. Fig 5. Follow-up radiograph after nine months, showing coronal restoration that was less than ideal. Fig 6. Diagnostic radiograph of another referred tooth (tooth #16). Fig 1. Working length, together with complete removal of the old restoration.