ABSTRACT
BACKGROUND: Absorption of the alveolar bone subsequent to tooth extraction is a long-term process, especially in the anterior tooth region where the buccal part of the ridge undergoes a prominent remodeling process after tooth extraction. Socket shield technique (SST) recently reported may be a new choice for peri-implant tissue preservation. OBJECTIVE: To give an overview on the principle, interface basis and application of SST in implant dentistry. METHODS: The first author searched the PubMed, Ovid, CNKI, VIP and WanFang databases for relevant articles published from January 1990 to October 2017. The keywords were "socket shield technique;root-membrane technique; root-implant; implant proximity to teeth; dental-contected implants; dentointegration;cementum formation on implant surface" in Chinese and English, respectively. RESULTS AND CONCLUSION: SST aims to maintain alveolar bone and gingival tissues by preserving partial tooth root with its periodontium-bundle bone intact, which is an alternative strategy for tissue preservation in esthetics zone.
ABSTRACT
<p><b>OBJECTIVE</b>To explore the relationship between the -344T/C polymorphism of aldosterone synthase (CYP11B2) gene and essential hypertension in Chinese Mongolian population.</p><p><b>METHODS</b>By cluster-sampling method, a total of 1575 Mongolian people in Tongliao city of Inner Mongolia were included in this study. And 417 subjects were normotension, 596 subjects were prehypertension and 562 subjects were essential hypertension. A survey was conducted to collect data by personal interview using a standard questionnaire, meanwhile fasting blood samples were drawn. Height, weight, waist circumference, blood pressure, blood-fat indexes and fasting plasma glucose were measured. The variant genotypes of CYP11B2 were identified by PCR assays. The relationship between the -344T/C polymorphism of CYP11B2 gene and essential hypertension were analyzed by multinomial logistic regression model.</p><p><b>RESULTS</b>Crude prevalence of prehypertension among Mongolian people was 37.84% (596/1575) and hypertension was 35.68% (562/1575). The age-standardized prevalence of prehypertension was 38.57% and hypertension was 31.53%. The frequency of the T and C allele was 0.66 (481/728) and 0.34 (247/728) for normotension group, 0.69 (696/1042) and 0.33 (346/1042) for prehypertension group, 0.71 (706/998) and 0.29 (292/998) for hypertension group. The multiple logistic models showed CYP11B2 variant genotypes were associated with prehypertension (TT/CC, OR = 1.33, 95%CI: 0.87 - 2.01; TC/CC, OR = 1.74, 95%CI: 1.13 - 2.67; TC + TT/CC, OR = 1.49, 95%CI: 1.01 - 2.22); CYP11B2 variant genotypes were associated with hypertension (TT/CC, OR = 1.70, 95%CI: 1.07 - 2.70; TC/CC, OR = 1.59, 95%CI: 0.98 - 2.50; TC + TT/CC, OR = 1.66, 95%CI: 1.06 - 2.58).</p><p><b>CONCLUSION</b>CYP11B2 gene -344T/C polymorphism were associated with essential hypertension in Chinese Mongolian population.</p>