Bone biological plate for stabilization of maxillary inferior repositioning

Inferior repositioning of the maxilla to correct vertical maxillary deficiency has been one of the more unstable orthognathic procedures performed. Different surgical techniques have been proposed to stabilize downward movement of the maxilla. The aim of this study was to evaluate the skeletal stability of maxillary anterior downgrafting using bone biological plates in association to bone plates and bone graft for skeletal stabilization.

The records of 6 patients were evaluated cephalometrically, analyzing the presurgical, immediate postsurgical and long-term follow-up radiographs. All patients had one-piece Le Fort I osteotomy with anterior downgraft of at least 2 mm at point A. Any horizontal movement of the maxilla concomitant with the downgraft was no more than 5 mm. Rigid fixation with titanium miniplates and screws and with bone biological plate was used to stabilize the maxilla. In the sample of 6 patients, 3 underwent one-jaw (maxilla only) surgery and 3 two-jaw surgery.

The mean surgical inferior downgrafting at point A was 5+/-1.4 mm (P<0.001) with a relapse of 0.16+/-1. 63 mm (3.2% of surgical movement). The mean surgical inferior downgrafting at the anterior nasal spine (ANS) was 5.66+/-1.36 mm (P<0.001) with a relapse of 0.41+/-1.56 mm (7.32% of surgical movement). Relapse in the vertical dimension failed to reach any statistical significance for all maxillary landmarks.

Anterior downgrafting of the maxilla with this fixation method seems to be a stable and predictable procedure. The use of bone biological plates seems to substantially improve skeletal stability even if further investigations with a more consistent sample of patients is required.