[Analysis of trends on smoking prevalence and its risk factors in Shaanxi province 2007-2015].

Objective: To analyze the trend of smoking prevalence and its risk factors among adults in Shaanxi province from 2007 to 2015. Methods: We used data from China Chronic Disease and Risk Factor Surveillance in 2007, 2010, 2013 and 2015. The current smoking prevalence and trends of the four surveys were calculated. Its risk factors were analyzed by multivariate logistic regression from each survey and then from all pooled data of the three surveys. Results: The number of participants in 2007, 2010, 2013 and 2015 was 1 542, 3 000, 10 166 and 6 330, respectively. The current smoking prevalence dropped from 34.34% in 2007 to 26.22% in 2013, but increased to 28.33% in 2015 (trend χ(2) test: Z=2.53, P=0.01). The results from four pooled data showed that the current smoking prevalence of men was higher than that of women (OR=75.03, 95%CI: 63.57-88.55). The current smoking prevalence of people aged 45-59 was higher than that of people aged 18-44 (OR=1.28, 95%CI: 1.15-1.41). In addition, the current smoking prevalence of those who were educated for 7-9 years and more than 9 years were higher than those who were educated for less than 6 years (people with education for 7-9 years OR=1.44, 95%CI: 1.29-1.61; people with education >9 years OR=1.43, 95%CI: 1.26-1.63). The current smoking prevalence of the single was lower than those of married/cohabitants (OR=0.54, 95%CI: 0.37-0.77). The current smoking prevalence of retirees were lower than those of employees (OR=0.46, 95%CI: 0.38-0.57) and smoking prevalence of alcohol drinkers were higher than those of non-drinkers (OR=2.92, 95%CI: 2.67-3.19). Conclusion: From 2007 to 2015, the current smoking prevalence of Shaanxi population was high and the trends remained stable. It is necessary to strengthen smoking control and health education for men, people over 45 years old, people with education level 7 years and above, and working personnel in Shaanxi province.

[Preliminary safety and stability assessment of orthodontic miniscrew implantation guided by surgical template based on cone-beam CT images].

OBJECTIVE: To develop surgical templates for orthodontic miniscrew implantation based on cone-beam CT(CBCT)three-dimensional(3D)images and to evaluate the safety and stability of implantation guided by the templates. METHODS: DICOM data obtained in patients who had CBCT scans taken were processed using Mimics software, and 3D images of teeth and maxillary bone were acquired. Meanwhile, 3D images of miniscrews were acquired using Solidworks software and processed with Mimics software. Virtual position of miniscrews was determined based on 3D images of teeth, bone, and miniscrews. 3D virtual templates were designed according to the virtual implantation plans. STL files were output and the real templates were fabricated with stereolithographic appliance(SLA). Postoperative CBCT scans were used to evaluate the implantation safety and the stability of miniscrews were investigated. RESULTS: All the templates were positioned accurately and kept stable throughout the implantation process. No root damage was found. The deviations were(1.73±0.65)mm at the corona, and(1.28±0.82)mm at the apex, respectively. The stability of miniscrews was fairly well. CONCLUSIONS: Surgical templates for miniscrew implantation could be acquired based on 3D CBCT images and fabricated with SLA. Implantation guided by these templates was safe and stable.