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Objective: To study the characteristics of soft-tissue integument and the differences between soft-tissue and hard-tissue topography in malocclusions., Methods: 144 female patients, 12-15 years old, were selected. They were divided into class I, class II and class III groups according to the value of angle ANB which was measured on the pre-treatment cephalographs. Each group had 48 patients. Each patient had same type of skeletal pattern and occlusal pattern, full set of permanent teeth and none of cranofacial soft-tissue and hard-tissue diseases. 4 pairs of measurements describing soft-tissue and hard-tissue sagittal facial pattern and the prominence of lips and incisors were measured on each cephalograph. They were angle SnNsB', angle ANB, angle NsSnPos, angleNAPo, UL-SnPos, UI-APo, LL-SnPos and LI-APo. The distribution of soft-tissue sagittal facial pattern in each skeletal group was analyzed. The differences between angle SnNsB' and angle ANB, angle NsSnPos and angle NAPo, UL-SnPos and UI-APo, LL-SnPos and LI-APo were calculated in each patient. Then we calculated the means and the ranges of these differences in each group, the probability of positive and negative difference between each pair of measurements in each group were calculated too. Chi2 test on those probabilities were performed between the three groups. The mean difference between each pair of measurements was then analyzed by ANOVA between the three groups., Results: The disharmony between soft-tissue and hard-tissue sagittal facial pattern was found in 20%-30% of malocclusion patients. There were more or less differences between soft-tissue and hard-tissue topography and the ranges of their variation were quite wide. The soft-tissue integument increasingly tended to augment the convexity of soft-tissue facial profile when skeletal pattern varied from class II to class I to class III, at the same time, tended to increase upper lip prominence and decrease lower lip prominence., Conclusion: On the average, soft-tissue integument tends to camouflage the abnormality of hard-tissue topography. But as to individual, the relative independence of soft-tissue integument makes it important to notice the influence of soft tissue on treatment planning and results.

Objective: To investigate the microbiological changes of subgingival microbials in patients with gingivitis and wearing fixed orthodontic appliances., Methods: 48 subjects (10 to 17 years old) with gingivitis, and wearing fixed orthodontic appliances, were divided randomly into three groups (placebo, NS and CH). Placebo group had normal saline mouthrinse; only and no oral hygiene instruction (OHI). The NS group had OHI and normal saline mouthrinse; The CH group had OHI and 0.12% chlorhexidine gluconate mouthrinse. Bacterial examinations were carried out on baseline, one week, one month and three months after scaling. The bacterial examination was carried out. The percentage of coccus, bacillus and spirochete was calculated., Results: In placebo group and NS group, the percentage of coccus increased up to the third examination then dropped down. The spirochete's percentage changed inversely. CH group maintained an increasing trend in coccus' percentage and decreasing trend in spirochete's percentage. The percentage changes of coccus and bacillus between placebo group and CH group are statistically significant (P < 0.05)., Conclusions: During the three-month examination, the CH group had better microbiologic change than the other two groups.