Changes in bone blood flow in segmental LeFort I osteotomies.

OBJECTIVE

The aim of the present study was to investigate the effect of segmentation and different movements of the segments in LeFort I osteotomies on the bone blood flow (BBF).

MATERIAL AND METHODS

The study sample of the prospective cohort study was composed of subjects scheduled to undergo 3-piece LeFort I osteotomies and simultaneous BSSO for correction of developmental skeletal deformities. The primary predictor variables were: time (T1, before LeFort I osteotomy; T2, after LeFort I osteotomy; T3, after segmentation and fixation of the maxilla) and magnitude of maxillary movement in the sagittal, vertical, and transverse planes measured in millimeters (mm). The subjects were assigned to 2 risk groups (high/low) depending on the amount of the movement. The primary outcome variable was maxillary bone blood flow measured with a laser Doppler at 4 sites: premaxilla, right and left maxillary lateral segments, and the mandible.

RESULTS

No significant difference was observed among the 3 maxillary regions. The mean decrease of the maxillary BBF between T1 and T2 as well as the reduction of BBF between T2 and T3 were statistically significant for all regions (P = .028 to P = .005 for T1/T2; P = .003 to P = .028 for T2/T3). No significant difference could be found between the 2 risk groups of maxillary movements.

CONCLUSIONS

Multisegmental maxillary osteotomies lead to a significant reduction of BBF. Moderate maxillary movements have no significant influence on the blood supply.