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 PowerPoint. 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.