To evaluate objectively the outcome of the Abbe flap procedure, an anthropometric ratio--the lip index--is introduced. The lip index is the ratio of the labiale superius-tragion to the labiale inferius-tragion. It represents the protrusion of the upper lip in relation to the lower lip. It has been assessed in preoperative and postoperative photographs of 19 patients who underwent an Abbe flap procedure. The values were compared with the values found in noncleft patients. In all 19 patients, postoperative values were found to have normalized. This study indicates that the lips are in better harmony postoperatively than they were preoperatively.