Outcome of non-surgical re-treatment

The purpose of this review was to critically analyze the relevant literature in order to synthesize an overview on the clinical outcomes (radiographically judged periapical healing and tooth survival) following root canal re‐treatment and the factors influencing them. A further aim was to explain the findings on the basis of current knowledge and understanding. The relevant literature was captured and critiqued using the principles of a systematic review. The data were classified into a coherent structure for analyses and presentation but are not presented as a systematic review; rather, the authors have chosen a narrative style to enable integration of the clinical outcomes with relevant findings from laboratory and animal studies. Overall, the outcomes were similar to those for teeth undergoing primary treatment with common factors influencing the outcomes. The major differences between the outcomes of primary and secondary root canal (re‐)treatment reside only in the ability to predictably access and negotiate the root canal system to the (residual) apical infection. The data offer a very favorable prognosis for non‐surgical root canal re‐treatment performed to guideline standards