Comparison of scleral show alterations following Le Fort I osteotomy with either maxillary impaction or lengthening

Abstract

This study aimed at evaluating changes in scleral show following Le Fort I osteotomy with either impaction or lengthening of the mid face. Patients who underwent Le Fort I osteotomy were included. The patients were divided according to the direction of the movement: group 1 underwent maxillary advancement and impaction, while group 2 underwent maxillary advancement and lengthening. Standardized preoperative and 6-month postoperative photos were superimposed using Microsoft Power-Point. The inferior visible scleral area was assessed with landmarks and measured separately using ImageJ software. Marked scleral surface area was determined using pixel count. A total of 36 consecutive patients were included. The mean maxillary advancement in the patients was 4.16 +/- 2.14 mm. The mean impaction in group 1 (n = 21) was 1.06 +/- 1.49 mm, while the mean vertical lengthening in group 2 (n = 15) was 1.54 +/- 1.65 mm. The difference in improvement in the inferior scleral show between the groups was not statistically significant. Preoperative (180 +/- 118.2 mm) and postoperative (147.75 +/- 92.2 mm) scleral show significantly improved (p = 0.012) in both groups. Scleral show can be overlooked for movements under 6 mm while planning for maxillary orthognathic movement, as it improves regardless of the desired movement.