Evaluation of soft tissue profile changes around the nose and upper lip following maxillary anterior alveolar osteotomy with Wassmund and Wunderer technique in Japanese.

Purpose: The extent to which maxillary anterior alveolar osteotomy alters the facial profile remains unclear. The present study retrospectively analyzed and evaluated changes in maxillary anterior fragments and soft tissue from the nose to upper lip from pre- to postoperatively in patients who underwent the Wassmund and Wunderer (WW) technique.

Methods: Thirty-seven Japanese patients with maxillary prognathism underwent orthognathic surgery with the WW technique were retrospectively included in the present study. Changes in both hard- and soft-tissue landmarks and correlations between both tissues were evaluated using lateral cephalograms taken immediately before and ≥6 months after orthognathic surgery.

Results: The maxillary anterior segment showed predominantly posterior movement, with only slight upward movement. Posterior shift and lingual inclination of the maxillary anterior teeth were prominent. As for soft tissues, the change in the nasal tip was small and posterior change was large in the subnasal and upper lip areas. Nasolabial angle, nasal height, and inclination of nasal tip increased, while upper lip protrusion, nasal tip angle, and philtrum length decreased. Correlations were found between posterior changes in hard tissues and posterior changes in soft tissues. Among these, posterior changes and lingual inclination of the maxillary anterior teeth strongly correlate with posterior changes of the upper lip.

Conclusion: Posterior shift of the maxillary anterior segment using the WW technique is useful because it can greatly improve the protrusion of the upper lip while minimizing nasal morphological changes, and the positioning of the maxillary anterior teeth may be an important key factor.