Condylar Resorption after Orthognathic Surgery: A Review of Risk Factors with a Proposed Algorithm of Treatment

This study aimed to critically reanalyze systematic reviews of patients suffering from condylar resorption (CR) and summarize the current scientific pieces of evidence with a focus on a possible relationship between CR and orthognathic surgery (OS). The work followed the "Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol" guidelines and was registered in the International Prospective Register of Systematic Reviews (registration number: CRD42020168660). The search strategy produced 143 articles. After reading the abstracts, 113 articles were excluded, and the full-text articles in English of the remaining 30 studies were separately examined for eligibility by 2 authors, with 20 of them being excluded because they did not meet the inclusion criteria. Finally, 10 systematic reviews were processed for critical evaluation. Young female patients with a high mandibular plane angle, diminished posterior facial height, posteriorly inclined condylar neck, and a counter-clockwise jaw rotation, are more likely to develop CR after OS. The most common procedure associated with CR in the included systematic reviews was the bimaxillary OS followed by bilateral sagittal split osteotomy. Hence, extreme caution and surgical modification should be used in these high-risk conditions. There is still a need for more evidence on the risks of OS or iatrogenic factors during the fixation of various osteosynthesis devices because it is still inconclusive and requires further justification.