The effects of orthodontic treatment on the morphology of temporomandibular joint of the adult with the low angle Class II malocclusions: a CT study / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To analyze the effects on the morphology of temporomandibular joint (TMJ) of the adult with the low angle Class II malocclusions before and after orthodontic treatment comparatively. To provide the references for the orthodontic treatment of the adults.</p><p><b>METHODS</b>19 adult patients with low angle Class II malocclusions were chosen and treated with Damon self-ligating braces. The examinations of 16-slice spiral CT were taken before and after the orthodontic treatment. The parameters of skeletal morphology of TMJ were measured in the multiplanar reconstruction (MPR) images. The results were analysed statistically.</p><p><b>RESULTS</b>The rate of condyles in a center position in the glenoid fossa after the treatment was 52.6%(20/38), and the rate of retrodisplacement was 31.6% (12/38). The position of the condyles before and after the orthodontic treatment had significant differences (P<0.05, chi2=4.41, chi2=5.32). The mean value of the anterior oblique angle of condyle decreased by 2.32 degrees +/- 1.78 degrees after treatment, meanwhile the average height of the condylar head increased by (1.07 +/- 0.29) mm. There were significant differences in both results before and after treatment (P<0.05).</p><p><b>CONCLUSION</b>The orthodontic treatment can make the TMJ structures stable and beneficial to relieve the symptoms by moving the condyle forward, increasing the height and reconstructing the anterior oblique angle of condyle on adult patients with low angle Class II malocclusions.</p>

Investigation and Analysis on Knowledge,Attitude and Practice of Environmental Health among Urban and Rural Residents in Four Areas in China / 环境与健康杂志

Objective To study the status of knowledge-attitude-practice (KAP) of environmental health among urban and rural residents and the influencing factors. Methods Totally,4 607 urban and rural residents from Lanzhou,Taiyuan,Shanghai and Qingdao were recruited and investigated by the self-designed questionnaire from July 3rd to August 10th 2007. In the questionnaire,a certain number of related questions were designed mainly on environmental health knowledge,attitude and practice. The datas were analyzed with SPSS13.0 software. Results The average scores of environmental health knowledge,attitude and practice of urban and rural residents were 4.14?1.30,4.88?0.85 and 4.05?1.11 respectively. The main influencing factors of environmental health knowledge were education background (?=0.220,P