Relationship between the sequence of lip and palate repair and maxillary growth: an experimental study in beagles.

The present study was designed to evaluate the relationship between varying sequences of lip and palate repair and maxillary growth. To investigate this problem, an experimental study using beagles was conducted to assess the influence of three different sequences of lip and palate repair. The first sequence constitutes the commonly accepted approach of lip repair first, palate repair second. The second sequence was reversed: palate repair first, lip repair second. The third sequence consisted of simultaneous lip and palate repair. Using 70 eight-week-old beagles, we tested the following hypothesis: The sequence of lip repair first and palate repair second is less detrimental to maxillary growth than the other two sequences. The animals were assigned to two control groups (unoperated and unrepaired animals) and three experimental groups, in which three different sequences of repair were executed. Upon sacrifice, 11 maxillary variables were measured directly from cleaned skulls and analyzed by univariate and multivariate techniques. The most important finding from this analysis is that the commonly accepted sequence of cleft lip and palate repair (lip first, palate second) is less detrimental to maxillary growth than repairing the palate first and the lip second or simultaneous closure of both defects.