Background: Cleft lip and palate develops during embryogenesis due to an alteration in the fusion of the tissues which will form the upper lip and palate. The rate of occurrence in Chile is 1.6 per 1000 live births. The object of the present study was to determine the effectiveness of the Grayson nasoalveolar molding appliance in reducing the gap between the alveolar segments in cases of unilateral cleft lip and palate by sex, age at start of treatment, initial gap between the alveolar segments, and number of checkups.
Methods: The study design was quasi-experimental, with measurements taken before and after surgery and no control group. The authors studied the medical records and models of a sample of 52 patients with complete unilateral cleft lip and palate who were discharged after treatment using Grayson nasoalveolar molding appliance. Treatment was considered effective when the final gap was 3 mm or less. Then the percentage of cases in which treatment was effective, applying statistical tests, including log regression, to assess the influence of other variables was calculated.
Results: The authors observed that the Grayson nasoalveolar molding appliance was effective in 69.23% of patients. Of the variables studied, the initial gap presented statistically significant differences (initial gap of 8-12 mm, effectiveness 82.61%); in the log regression, the same variable presented a statistically significant difference in the adjusted odds of effectiveness.
Conclusion: Grayson nasoalveolar molding appliance presents good effectiveness in reducing the gap between the alveolar segments in patients with unilateral cleft lip and palate, especially in cases with a gap of 8 to 12 mm.