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

Area of Science:

• Orthodontics and Maxillofacial Surgery
• Dental Biomechanics

Background:

• Orthognathic surgery protocols rely on pre- or post-surgical arch preparation.
• Incisor decompensation is key for normalizing incisor guides in three dimensions.
• Surgical movement extent is dictated by the final incisor position.

Purpose of the Study:

• To investigate the relationship between incisor decompensation magnitude and orthognathic surgery.
• To assess the risk of developing or exacerbating temporomandibular dysfunction (TMD) due to these procedures.

Main Methods:

• Analysis of orthodontic preparation and incisor decompensation.
• Evaluation of incisor position planning for extraction/non-extraction decisions.
• Correlation of surgical movements with temporomandibular joint (TMJ) stress and TMD.

Main Results:

• Incisor decompensation (sagittal, vertical, transversal) influences surgical movement placement and amplitude.
• Loss of occlusal guide control during orthodontic preparation did not appear to induce TMD.
• The degree of pre-existing TMD influences the scope of surgical movements and decompensation targets.

Conclusions:

• Incisor decompensation plays a significant role in determining the scope of orthognathic surgical movements.
• Orthodontic preparation involving incisor decompensation may not inherently lead to TMD.
• TMD severity is a critical factor in moderating surgical movements and setting decompensation objectives.