Qualitative correlation between postoperatively increased vertical dimension and mandibular position in skeletal...

Area of Science:

• Orthodontics and Dentofacial Orthopedics
• Surgical Orthodontics

Background:

• Skeletal class III malocclusion requires complex treatment.
• The surgery-first approach (SFA) is a common treatment strategy.
• Understanding postsurgical changes is crucial for treatment outcomes.

Purpose of the Study:

• To investigate the relationship between postsurgical vertical dimension (VD) and mandibular setback in skeletal class III patients treated with SFA.
• To model the pathway by which VD influences the final B point position posttreatment.

Main Methods:

• Retrospective analysis of 40 patients with skeletal class III bimaxillary SFA.
• Utilized cone beam computed tomography (CBCT)-generated cephalograms.
• Constructed a partial-least-square path-modeling (PLS-PM) model to analyze variables.

Main Results:

• An increase in postsurgical vertical dimension (VD) was associated with a decrease in the absolute value of the final mandibular setback.
• This finding suggests increased postoperative mandibular changes due to physiological responses.
• The PLS-PM model confirmed the effect of VD on the final B point position.

Conclusions:

• Partial-least-square path-modeling (PLS-PM) effectively addresses collinearity in cephalometric data.
• Increased postsurgical occlusal vertical dimension influences the changeability of the B point position posttreatment.
• This highlights the importance of considering VD in predicting treatment outcomes for SFA.