Root resorption of the maxillary lateral incisor caused by impacted canine: a literature review

Root resorption of maxillary lateral incisors caused by erupting canines is well known and a relatively common phenomenon. However, much debate and conflicting evidence exists with regard to the actual resorption trigger and potential etiological factors involved. Consequently, there are no obvious clinical clues concerning prevention and diagnosis as well as subsequent treatment decisions. The introduction of cone beam computer tomography has recently allowed drawing a new and much more documented light on the diagnostic and therapeutic strategies. However, no investigations have determined that this new information may result in another and better diagnostic approach and an improved treatment outcome. Therefore, the present review will attempt to summarize the existing evidence on two- and three-dimensional images and try to link the radiological observations to any further preventive, diagnostic, and/or therapeutic measures. Detection thresholds, accuracy, and reliability of impacted canine localization and neighboring root resorption risks will also be considered. This review demonstrates how adding a third-dimension to the radiographic information may notably alter the prevalence of root resorptions and descriptions of this prevalence. In any case, further investigation is needed to determine resorption detection thresholds in various two- dimensional and three-dimensional imaging techniques, as well as to determine therapeutic thresholds and criteria for strategic tooth extraction based on radiographic manifest and not manageable resorption lesions.