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[Effect of maxillary protraction in patients with unilateral cleft lip and palate and anterior crossbite].

OBJECTIVE
To investigate the different changes after maxillary protraction between the cleft and non-cleft patients with anterior crossbite.


METHODS
Prospective controlled clinical trial was carried out. Eighteen patients (aged 9.6 +/- 1.2 years) with unilateral cleft lip and palate (UCLP) were chosen as the experimental group. Eighteen non-cleft patients (aged 9.8 +/- 1.4 years) with similar malocclusions were selected as control group. All the patients were before puberty according to the evaluation of the hand wrist radiograms. Hyrax appliance and reverse headgear were used in both experimental and control groups. Lateral cephalometric radiographs were taken before and after treatment. Computerized cephalometric analysis was carried out. Paired t tests or t test were performed using software package SAS 8.1.


RESULTS
After treatment, the main changes in experimental group were: SNA +1.45 degrees , A-TFH +2.19 mm, SNB -2.18 degrees , ANB +3.64 degrees , MP/SN +2.78 degrees , LL-EP +0.88 mm in UCLP group. And in control group were: SNA +1.42 degrees , A-TFH +2.12 mm, SNB -1.32 degrees , ANB +2.68 degrees , MP/SN +1.47 degrees , LL-EP -1.37 mm.


CONCLUSIONS
Before puberty, maxillary protraction could accelerate maxillary forward growth in UCLP patients and the changes were similar to non-cleft patients. The occlusal relationship and soft tissue profile were improved significantly in both patients with or without cleft. The amount of mandibular posterior rotation in patients with UCLP was larger than in those with no cleft.