Effect of maxillary protraction in patients with unilateral cleft lip and palate and anterior crossbite / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the different changes after maxillary protraction between the cleft and non-cleft patients with anterior crossbite.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSIONS</b>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.</p>

Dental arch characteristics of the facial asymmetry / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the characteristics of dental arches in the patients with facial asymmetry.</p><p><b>METHODS</b>20 facial asymmetrical patients were chosen as the study subjects. They were 8 boys and 12 girls, aged from 12-year to 16-year old. 20 normal occlusion persons without signs of facial asymmetry were chosen as control. Dental casts were measured by 3-dimension measuring machine. Dental arch asymmetry, coordination between upper and lower dental arch, and dental inclination were measured. SAS 6.03 was used in statistical analysis.</p><p><b>RESULTS</b>The distance from cuspid and the first bicuspid to the median palatal raphe in the side of crossbite was larger than that of contralateral side in maxilla. The distance from cuspid, bicuspids and the first molar to the midline in the side of crossbite was smaller than that of contralateral side in mandible (P < 0.05). The dental arch width of cuspid and first premolar in maxilla was smaller than that of mandible (P < 0.05) . Significant buccal inclination of the maxillary posterior teeth coupled with lingual inclination of the mandibular posterior teeth was found on the crossbite side. In contrast, significant lingual inclination of the maxillary posterior teeth coupled with buccal inclination of the mandibular posterior teeth was found on the contralateral side (P < 0.05).</p><p><b>CONCLUSION</b>The width of upper anterior dental arch was smaller, and the inclination of upper and lower posterior teeth between crossbite side and counterside was different in facial asymmetry patients.</p>