Root resorption, an unwanted sequela of orthodontic treatment, has received much attention in the recent past. This is clearly evident from the enormous amount of literature published regarding this single iatrogenic issue. These research works should provide practitioners with great insight into the clinical, histologic, therapeutic, predictive, and genetic aspects as well as the molecular basis of the resorptive process. Yet the scientific community reading these reports is left with confounding questions requiring a proper organization of the published literature. This review is aimed at answering some critical issues concerning root resorption after orthodontic treatment. It also tries to update the theoretical information regarding the resorptive process, with an insight into recent human genetic and molecular-level research.