Objective: To determine the dimensional changes of alveolar bone cleft after using Khon Kaen University intra-oral contractionscrew plate together with nasal elevator molding and labial strapping prior to surgical lip repair.
Material and Method: Maxillary alveolar ridge models of 17 infants with complete unilateral cleft lip and palate between the
year 2015 and 2017 were evaluated at the initiation of molding therapy (T1) and after therapy (T2) before cheiloplasty. Linear
dimensions, including cleft width, anterior arch width, posterior arch width, arch length, midline deviation, and arch circumference were recorded using a digital vernier caliper. Data were analyzed with paired t-test.
Results: Maxillary alveolar ridge models were collected at the start of treatment. The average age was 24.5 days. The results
showed that measurements at T1 were significantly decreased at T2 in the width of the alveolar cleft (p<0.001), anterior arch
width (p = 0.002), arch length (p<0.001) and midline deviation (p<0.001). On the other hand, arch circumference and posterior arch width showed a slight increase at T2.
Conclusion: The contraction-screw plate, supported by the labial strapping, was effective in reducing the severity of the
alveolar cleft width and anterior portion of the arch. The arches were more symmetrical and centralized to the midline which
would contribute to improved overall surgical correction and result in better repair of alveolar cleft.

Keywords: Unilateral cleft lip and palate, Nasoalveolar molding device