Root canal retreatment of the compromised tooth or extraction and implant rehabilitation?

OBJECTIVES The main objective of this Module is to describe the factors to be clinically evaluated in presence of a tooth with uncertain prognosis, i.e. when it is better to keep and retreat a previously root canal treated tooth or when to extract it and replace with an implant rehabilitation. Such situation and the decision making regarding techniques and operative procedures has become extremely frequent in daily routine. MATERIALS AND METHODS The main clinical studies that examined root canal retreatment and implant rehabilitation outcome were re ported and discussed. The main ana tomical, endodontic and prosthetic variables of these compromised teeth were analyzed and the decision mak ing approach were discussed. RESULTS Teeth affected by endodontic pathology are frequently associated to massive loss of enamel and dentin tissues. Their rehabilitation represents a hard challenge for clinicians. The compromised teeth can be endodontically retreated (secondary treatment). Unfortunately, their morphology and tissue alteration may be responsible for root fractures, root resorption and cervical decays, with an uncertain prognosis and success rate. Furthermore, retreatment pro cedures for compromised teeth re quire long working times and specific skills in endodontics practice, con servative dentistry, dental prosthesis and periodontology. For patients without medical risks and/or systemic pathologies, another clinical approach for endodontically treated compromised teeth can be the extraction and subsequent insertion of a dental implant and prosthetic rehabilitation (post-endodontic implant). Post-endodontic implants must be placed after some months from extraction in healthy mature bone (delayed implants), or immediately inserted after extraction (post-extractive implants). Hopeless seriously damaged teeth free from periapical lesions or affected by chronic periapical disease without signs and symptoms can be approached with post-extractive implants with advantage of reduced pro cedures. On the contrary, hopeless endodontically treated teeth affected by acute and symptomatic periapical lesions may be extracted and replaced only after healing and bone regeneration. Methods to prevent bone defect and reabsorption may be considered in the decision making. Infected apical sites are responsible for higher risk of no-osteointegration and potential implant failure. CONCLUSIONS Specialists in endodontics should know implantology because it represents an effective alternative to retreatment procedures for compro mised hopeless teeth in patients with out medical risks. A carefull and well-programmed implant may result in a more predictable and higher success rates than a complex and high risk endodontic treatment of teeth with large tissue destruction. Like sur gical root-end endodontics, post-end odontic implant placement may repre sent a choice for a high level therapeutic approach. CLINICAL SIGNIFICANCE Endodontists should know limits and advantages of implantology. They must evaluate the adequate surgical proce dures and implant insertion timing related to specific clinical situation. Finally, the endodontists must know the management of soft and hard tissues after tooth extraction and implant insertion.