Objective: The objective of this study was to assess the congenital and postnatal factors that affect the degree of malocclusion of Japanese patients with UCLP at Hokkaido University Hospital using multivariate statistical analysis.
Materials: All information of 135 subjects with UCLP was got from oral examination and radiograph taken at the initial examination at orthodontic clinic and from the case record of surgery. Plaster models were also taken before orthodontic treatment. The ages of the subjects ranged from 5 to 8 years with a mean age of 6.85 ±1.56 years. All primary surgeries for the subjects were performed at Hokkaido University Hospital. To assess the dental arch relationships (degree of malocclusion) of subjects, the Goslon Yardstick was used. Associations between various factors and dental arch relationships were assessed using logistic regression analysis.
Results: Twenty-two percent of the subjects were classified into unfavorable relationship (category rating 4 and 5) using the Goslon Yardstick. Using adjusted odds ratio, positive family history of Class III made the dental arch relationship significantly worse. Palatoplasty using pushback made the dental arch relationship significantly worse than palatoplasty using pushback with buccal flap. Pushback with buccal flap made the dental arch relationship significantly worse than two-stage palatoplasty.
Conclusions: The multivariate analysis suggested that family history of Class III and Å@Å@the types of palatoplasty were significantly correlated with the dental arch relationship of UCLP patients at Hokkaido University Hospital.