[Orthognathic surgery and joint dysfunctions: benefits or risks?]

The aim of this article was to present a synthesis of recent bibliographic data concerning the relationship between orthognathic surgery and temporomandibular disorders (TMD). Materials et Methods: A search of relevant articles published over the past ten years (2010-2020) was performed in PubMed using the keywords « orthognathic surgery » and « temporomandibular disorders »: 31 articles were included in the review. The data were classified in three main chapters: (1) the effects of orthognathic surgery on TMD, (2) the consequences of orthognathic surgery on the condylar position and (3) the musculo-articular complications of the orthognathic surgery.

The results of clinical studies show that the effects of orthognathic surgery on TMD are variable and difficult to predict, so that orthognathic surgery cannot be considered a reliable therapy for joint dysfunctions.

This review also sheds light on new aspects emerging from recent publications, such as the influence of bruxism, oral dysfunctions and psychological factors and the problem of condyle positioning with the development of techniques for modeling the stresses exerted on the condyle by the finite element method.

The risk factors for articular complications are poorly known. Female gender, skeletal class II, hyperdivergent profile, rigid osteosynthesis are often reported, but the most factor is the significant preexistence of a joint dysfunction (discal displacement in particular), which argues in favor of a systematic articular pre-operative evaluation including MRI of the temporomandibular joint.