Factors Influencing Subjective Orthodontic Treatment Need and Culture-related Differences among Chinese Natives and Foreign Inhabitants

Aim The aim of this survey was to compare Chinese natives and foreign inhabitants in Chengdu, China, with respect to： （1） attitudes towards dental appearance, （2） subjective orthodontic treatment need, and （3） the main factors influencing orthodontic treatment need. Methodology A total of 522 subjects, including 227 foreign inhabitants and 295 Chinese natives in Chengdu participated in the survey. A simple random sampling method was adopted and a face-to-face interview was conducted at some public sites using a questionnaire. Data was entered by two persons synchronously using Epidata 3.0, and SPSS 13.0 was used to analyze these data. Results 89.0% of foreign inhabitants were satisfied with their teeth compared to only 46.8% of Chinese natives. Females were more dissatisfied with their teeth than males. Chinese natives put improving appearance as the top priority （55.9%） for seeking orthodontic treatment; however, in foreign inhabitants, the main reason for seeking treatment was to improve masticatory function（44.1%）, followed by ＂to be pretty＂ （35.2%）. The importance of well-aligned teeth and self-perception of psychosocial impact of malocclusion were the same two main factors influencing subjective orthodontic treatment need （P〈0.05） in foreign inhabitants and Chinese natives. Sub- jective orthodontic treatment need between the two target groups was significantly different （P〈0.05）. Conclusion （1） It was very common that Chinese natives were dissatisfied with their dental appearance, and their subjective orthodontic treatment needs were high. （2） There were some differences in orthodontic treatment motives between the two target groups. （3） There were differences in subjective orthodontic treatment needs between foreign inhabitants and Chinese natives. However, the prominent influential factors were almost the same. There may be benefit to understanding subjective orthodontic needs of different races.

Effects of orthodontic load on the periodontium of autogenously transplanted teeth in beagle dogs

Objective:To observe the periodontal healing of autogenously transplanted teeth loaded orthodontically after autotransplantation in Beagle dogs.Methods:Forty-eight teeth were autogenously transplanted,24 of which were loaded postoperatively with orthodontic force at different time points and for different durations.Periodontal healing was evaluated by probing pocket depth(PPD),the expression of relevant proteins,and histomorphometric analyses.Results:The dental pockets of loaded and non-loaded teeth were both much deeper after the first postoperative week than before transplantation(P<0.05).Later,the PPD,which was measured after postoperative weeks 1,3,5,9 and 13,gradually became shallow.The expressions of alkaline phosphatase(ALP)and basic fibroblast growth factor(bFGF)were higher in loaded teeth than in non-loaded teeth(P<0.05),and in groups subjected to two weeks duration of loading than in other groups at the same load time point(P<0.05).For the same load duration,the expressions of ALP and bFGF in teeth loaded after postoperative week 4 were higher than those of other treatments(P<0.05).According to histomorphometric analyses,an orthodontic force on transplanted teeth applied after postoperative weeks 4 or 8 for two weeks duration should be favorable for periodontal healing.Conclusions:It is advisable to apply an appropriate magnitude of force on autotransplanted teeth,such as orthodontic force,at appropriate time points and for a suitable duration,to achieve the optimal clinical prognosis following autogenous tooth transplantation.These results may serve as a basis for subsequent studies in humans so as to make clinical improvements.