Three-dimensional analysis techniques--Part 4: Three-dimensional analysis of bone and soft tissue to bone ratio of movements in 24 cleft palate patients following Le Fort I osteotomy: a preliminary report.

The three-dimensional changes in the bone and the ratio of soft tissue to bone movement were investigated in a group of 24 cleft palate patients following Le Fort I osteotomy. CT scans were taken for each patient preoperatively and 1 year postoperatively. The scans were superimposed, radial measurements calculated, and the changes illustrated by two separate color scales. In all of the groups, there was a fairly consistent pattern of movement over the mandible. The soft tissues moved in a 1.25:1 ratio over the chin and canine regions, and reduced to 1:1 over the body. In the maxilla, there was a 1:1 movement in the midline increasing to 1.25:1 bilaterally over the alar bases for both the bilateral clefts and clefts of the secondary palate groups. In the unilateral cleft group, however, there was a greater degree of movement over the cleft than over the noncleft side.