Splintless Versus Conventional Maxillomandibular Advancement Surgery for Obstructive Sleep Apnea

Because the main objective of MMA for OSA is achieving the planned advancement and counter-clockwise rotation to relieve the upper airway collapse, anteroposterior translation of the maxilla and mandible, and pitch of the maxilla and mandible are the main study parameters.

The postoperative CT scan is superimposed on the preoperative virtual planning. The absolute difference between the planned value for a parameter and the postoperative acquired value will be calculated, which provides an intuitive accuracy measurement of MMA surgery.

Mediolateral and superoinferior movement of the maxilla and mandible in millimeters measured by CT scan

Roll and yaw of the maxilla and mandible in degrees measured by CT scan

The time between the start of incision and the suture of the incisions.

Blood loss during surgery

Intra- and post-operative adverse events/complications

The average number of apnea and hypopnea events per hour of sleep during a sleep study (polysomnography)

Number of times per hour of sleep that blood oxygen saturation drops by ≥3% from baseline during a sleep study

The minimum blood oxygen level (%) reached during a sleep study

Percentage of sleep time spent with blood oxygen saturation < 90% during a sleep study

Daytime sleepiness as assessed with Epworth sleep scale total score (range 0-24; higher scores indicate greater daytime sleepiness / worse outcome)

Functional status as assessed with Functional Outcomes of Sleep Questionnaire total score (range 5-20; higher scores indicate better functional status / less impairment due to sleepiness)

Sleep quality as assessed with Pittsburgh Sleep Quality Index global score (range 0-21; higher scores indicate worse sleep quality)

Patient's health status as assessed with EuroQol 5-Dimension 5-Level utility index (utility index ranges from <0 to 1; higher scores indicate better health-related quality of life)

Patient's health status as assessed with EuroQol 5-Dimension 5-Level visual analogue scale (VAS) score (VAS ranges 0-100, higher scores indicate better health status)

Quality of life as assessed with 36-Item Short Form Health Survey domain and summary scores (range 0-100; higher scores indicate better health-related quality of life)

Patient satisfaction with facial appearance as assessed using the FACE-Q questionnaire (range 0-100; higher scores indicate greater satisfaction with facial appearance / better outcome)

Patient's satisfaction with surgery outcomes as assessed with customized patient satisfaction questionnaire (5-point Likert scales; higher ratings indicate greater satisfaction)

Partner-reported assessment of snoring severity, snoring-related disturbance, and perceived postoperative facial appearance changes using a study-specific questionnaire completed by the participant's partner (higher ratings indicate greater snoring severity/disturbance or more positive perceived facial change, depending on the item).

Postsurgical relapse measures in translation parameters (anteroposterior, mediolateral, superoinferior) and rotation parameters (roll, pitch, yaw) of the maxilla and mandible. The discrepancy between immediately post-operation (1 week after MMA) and 2 years after surgery will be used to define the amount of relapse.

Facial soft tissue changes following MMA at various soft-tissue points. These are determined by the difference in 3D coordinates of soft tissue landmarks between baseline and 6 months after MMA;

Upper airway volume (mm³) measured using three-dimensional imaging analysis

Upper airway length measured using three-dimensional imaging analysis (mm)

Upper airway surface area (mm²) measured using three-dimensional imaging analysis

Minimum cross-sectional area (mm²) of the upper airway measured using three-dimensional imaging analysis

Lateral dimension of the upper airway minimum cross-sectional area (mm) measured using three-dimensional imaging analysis.

Anteroposterior dimension of the upper airway minimum cross-sectional area (mm) measured using three-dimensional imaging analysis.

Systolic and diastolic blood pressure

Incremental cost-effectiveness ratio (ICER) and incremental cost-utility ratio (ICUR).