[Orthognathic surgery: the incisor decompensation and its effect on articulation].

INTRODUCTION: The surgical protocols are based on arches preparation before or immediately after the surgical phase. Incisor guides normalization is achieved by incisor decompensation in three dimensions. Place and extend of surgical movements depend on the incisor position obtained at the end of orthodontic preparation. Extraction versus non extraction depends on incisor position planning. Orthognathic surgery induces muscular and temporo-mandibular joint stress which can cause temporo mandibular dysfunction (TMD). OBJECTIVES: This article studies relations between incisor decompensation amplitude, orthognathic surgical procedures and risk to create or to increase TMD. CONCLUSIONS: Sagittal, vertical and transversal incisor decompensation impact to place and amplitude of surgical movements. Incisor decompensation does not seem to induce TMD during orthodontic preparation even if occlusal guide controls are lost. Temporo mandibular dysfunction degrees define surgical movements area, moderate specially mandibular surgical movements and incisor decompensation objectives.