At birth, the lip is one of the most developed organs of the human body. The lip terminates its intensive development at preschool age . At the age of 2 to 9 years, the lip growth shows a difference between girls and boys. The lip is larger during this age range among boys than in girls . Lee  and Randal  criticized surveys of photos: since infants do not keep quiet, photographs are not standardized, and different enlargements can occur. Therefore, we avoided to use absolute values for the measurements. In his study, Lee carried out the measurements directly on the patient. This is also problematic since small children cannot keep quiet, the skin is soft and elastic and the measurements are difficult to reproduce. To circumvent the retrospective aspect of the no longer exactly determinable factor growth, only relative values were considered in this study. Therefore, errors of different imaging scales in photographs are eliminated because the values are simply normalized.
The final result of the cleft closure is essentially determined by the OP technique, the operator and the postoperative growth in the former cleft region. The wave-cutting technique, which had already proved itself in correctional procedures, was adopted as a primary treatment because it is more tissue-friendly and more flexible than the earlier methods. In addition, it uses the elasticity of the skin at the edge of the lip for lengthening the lips evenly . Of importance is the liberation of the musculature from an unphysiological attachment and the exact union of the circular muscle . This technique has a wide range of variations and allows individual consideration of the shape of the lip stumps . Another great advantage lies in the precise measurement possibility .
Millard’s rotation-advancement principle is used most frequently in its modifications worldwide. Millard himself called it “cut as you go” . It is very flexible and allows modifications during the cutting and the lip closure . The technique is tissue-saving and allows a complete mobilization of the lateral nasal ala and its placement in the appropriate position so the symmetry of the nostrils and the nasal floor can be restored at the same time. Because of the flow of the advancement flap, not only a balanced height compensation of the lip is possible but also a volume adjustment of the cleft side .
Our results on the lip Philtrum in the Millard group agree with the statement by Millard that shortly after the operation, the cleft side was shorter than the healthy side, but compensation took place over time . He also postulated that, in the case of wide clefts, a contraction of the cleft could be postoperative in the first 3 months. However, if the technique was applied properly, the result improved without any additional surgery after 6 months and showed almost perfect symmetry after 1 year. Investigations by Becker even showed a lengthening of the lips on the cleft side .
Lee  carried out measurements on the lip immediately after the operation and determined that incomplete clefts had a symmetry between the cleft and the healthy side, while complete lip clefts were shorter on the cleft side than on the healthy side. No improvement was noted a year postoperatively. Le Mesuier, Mulliken and Martinez-Perez, and Saunders et al. [4, 19, 20] also reported a shortened Philtrum on the cleft side according to the Millard technique. Millard acknowledged that the asymmetry was in some cases caused by the defect at the maxilla and recommended a lip adhesion operation, which already had been recommended by other authors [21,22,23], as well as a preoperative orthodontic treatment . Additionally, in Göttingen, the patients with lip-to-palate clefts were provided with the Latham plate before lip closure to position the jaw segments. This could explain why most of the patients in the present study had a symmetrical Philtrum until the fourth postoperative year. As clearly confirmed by our study, the symmetry course shows a clearly time-dependent behavior.
In the Pfeifer group, the Philtrum is briefly shorter after the operation and in the further examination course on the cleft side than on the healthy side. Although this technique is very common in the German-speaking world, it is not often reported in the literature. Maerker and Bull  found that the red and white border was symmetrical in 58 out of 83 examined children, whereas in 25 examined children, the cleft lip Philtrum showed a shortening and thus a distortion of the lip vermillion with step formation. Bitter  also noted a shortening of the lip Philtrum.
Regarding the vermillion length, we found contradictory statements. Mulliken and Martinez-Perez  found a very full vermillion in the patients who were operated with the Millard technique, whereas Noordhoff describes a deficit . These differences can also be explained with the different temporal course.
Märker and Bull found a very full upper lip in patients who had been operated with the Pfeifer technique .
In the present study, the total lip height is not significantly different in both groups. However, in the Pfeifer group, the deficiency of the Philtrum is compensated by a too plumb vermillion. This can be accompanied by esthetic limitations. For this reason, Pfeifer recommended that in case of an esthetic deficiency, a correction should be completed before the first day of school .
Over the whole study period, the two groups did not differ in mouth width, but the development of the horizontal dimension of the cleft side is, according to Pfeifer, until the fourth year, bigger than the healthy side; in the Millard group, it is the other way around. Lewis  also observed a narrowing of the lip width in the Millard group postoperatively. According to our study, Märker and Bull (1982) observed a widening in the first postoperative years .