Changing cleft widths: a problem revisited.

A study was undertaken to evaluate changing cleft widths and the timing of surgical repair of the lip in so far as it affects the types of cross-bite occlussion that result in cases treated by presurgical orthopedics (as practiced at Tufts-New England Medical Center Hospitals) and by purely surgical intervention. On the basis of the analyses carried out, the following conclusions were reached: 1. Both the alveolar cleft width prior to lip surgery and the arch form following lip surgery are significantly related, and are predictors of, the type of cross-bite occlusion that will result from purely surgical intervention. 2. Neither the alveolar cleft width prior to lip surgery nor the arch form following lip surgery is significantly related to, or is a predictor of, the type of cross-bite occlusion that will result from presurgical orthopedics. 3. For both presurgical orthopedic treatment programs and purely surgical treatment programs, there is a significant relationship between the arch form following palate surgery and the type of cross-bite occlusion that will result. 4. In cases treated by presurgical orthopedics there is a higher probability of achieving favorable occlusal relationships than in cases treated by purely surgical intervention. 5. In a period of 6 months following birth, but prior to lip surgery, presurgical orthopedics results in a smaller percentage reduction in alveolar cleft width than does treatment without the use of an appliance. However, the posterior cleft widths and posterior palate widths show comparable changes in size. 6. The larger anterior cleft width maintained by the use of presurgical orthopedics prior to lip surgery is completely compensated for following lip surgery, so that no significant difference remains between cases treated by presurgical orthopedics and those treated by purely surgical intervention. 7. Since previous findings showed a larger reduction in posterior cleft width in cases treated by presurgical orthopedics than in cases treated by purely surgical intervention and these results show that there is a comparable reduction in posterior cleft width when lip surgery is delayed until the age of 6 months, then early lip surgery tends to limit the natural reduction of the posterior cleft width. 8. Additional studies are needed. These studies must be based on as complete a description of the cleft and the treatment program as possible. It is the total implication for patient rehabilitation that must be considered in the evaluation of treatment outcomes.