The effect of the lip adhesion procedure on the alveolar arch. With special reference to the type and width of the cleft and the age at operation.

In a material of 89 wide clefts, we measured the effect of the lip adhesion on the width of the cleft, the deviation of the maxillary arch segments, and in bilateral clefts on the premaxillary protrusion. The width of the unilateral complete cleft diminished by two-thirds, on average, depending upon decreasing positive deviation of the major alveolar segment, while the minor segment did not react at all. In unilateral alveolar clefts the effect was in principle similar. In bilateral complete clefts the width of the cleft diminished by only 40-50%, on the average, and the protrusion of the premaxilla by 8-23%, while the primarily always negative segmental deviation decreased by about 40%. The age at operation within certain limits did not seem to influence the results in any significant way. Lip adhesion is thus recommended especially in wide unilateral complete clefts as an operative orthodontic procedure to facilitate subsequent final repair.