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Abstract – Objective: The aims of this study, which are part of the gerontological and geriatric population studies in Göteborg, Sweden (H70), were to describe cohort differences and trends in dental status and utilization of dental care in 70‐year‐olds. The study is based on five cohorts examined in 1971/72, 1976/77, 1981/82, 1992/93 and 2000/01 (called cohort I, II, III, V and VI, respectively). The total number of participants was 2290 and varied between 386 and 583 in the different cohorts. The proportion of dentate 70‐year‐olds changed gradually from 49% in the first to 93% in the last cohort. The mean number of teeth in the dentate 70‐year‐olds was 14 in cohort I and 21 in cohort VI. The proportion of subjects with 20 or more teeth changed from 13% in cohort I, to 20% in cohort III, and to 65% in cohort VI. In cohort I, 76% of the 70‐year‐olds had some kind of removable denture; 37% in cohort III, but only 17% in cohort VI. About 20% of all 70‐year‐olds in cohort I reported regular yearly visits to a dentist. The corresponding figures in cohort III and cohort VI were 50% and 80%, respectively. Even though positive cohort trends were observed in all studied subgroups, factors such as low education, smoking, being un‐married, having high waist circumference and being physically inactive were negatively associated with dental status at the end of the study period as well as at the beginning.  相似文献   
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The aim of this study is to document reasons for tooth loss in disadvantaged Jordanians who seek free dental care at the University Hospital/Dental Clinics. A 4-year (1998-2001) prospective study was undertaken involving 2200 randomly selected patients from this subpopulation. Of their 3069 lost teeth, 46.9% were lost due to caries and its sequel; 18% were lost because of periodontal disease; 8% were lost for a combination of caries and periodontal disease; 19.4% for pre-prosthetic reasons; 4% for orthodontic reasons; 2.8% for eruption problems and 0.7% due to trauma. Logistic regression analysis for reasons of tooth loss in this sector revealed that caries and its sequel was the predominant cause of tooth loss in patients 相似文献   
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HLA antigens have been considered as risk factors for periodontitis. Differences in prevalence and in the extent of attachment loss between males and females have suggested that gender-dependent HLA deviations could play a role in individual predisposition to periodontitis. The aim of the present study was therefore to investigate the incidence of gender-dependent HLA associations in 50 patients with generalized aggressive periodontitis (AP) and 102 patients with chronic periodontitis (CP) in comparison to 102 probands without any attachment loss caused by periodontitis. HLA typing was carried out using a microlymphocytotoxic test and a polymerase chain reaction with sequence-specific primers (PCR-SSP). Female AP patients showed an increase in the frequency of HLA-A*68/69 and a decrease in the frequency of DRBblank* (non-DRB3/4/5*) and DQB1*05-positive probands. Only in female CP patients was HLA-DQB1*0303 absent, whereas HLA-DQB1*06 homozygosity increased significantly. With regard to the (AP + CP) periodontitis group as a whole, the increased frequency of HLA-DQB1*06 homozygosity in females was similar to the findings obtained in the AP group. Evidently, gender is a confounding variable, which should be considered in further studies of HLA and periodontitis.  相似文献   
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PURPOSE: This study was designed to determine the effect of opacifiers used at different ratios on the color stability of pigmented A-2186 silicone maxillofacial elastomers and to evaluate the color spectrophotometrically before and after artificial aging. MATERIALS AND METHODS: Sixty experimental groups of elastomers were made using various concentrations (5%, 10%, and 15%) of 4 opacifiers (Georgia kaolin powder neutral, kaolin powder calcined, Artskin white, and dry pigment titanium white) with 1 of 5 dry earth cosmetic pigment groups (no pigment [control], red, yellow ochre, burnt sienna, and a mixture of all pigments). Five specimens of each elastomer were tested, for a total of 300 specimens. All specimens were placed in an aging chamber and artificially aged by exposure to light, water spray, fluctuating temperatures, and humidity. CIE L*a*b* values were measured by spectrophotometer. The color differences (Delta E*) at various exposure energies (150, 300, and 450 kJ/m(2)) were subjected to 4-way analysis of variance with repeated measures (super ANOVA). Mean values were compared with Tukey-Kramer intervals calculated at the 0.05 significance level. RESULTS: The trained human eye can detect color changes (Delta E*) greater than 1.0. Adding all pigments to any of the kaolin groups did not protect silicone A-2186 from color degradation over time. Mixing red pigment in all groups at all times drastically increased DeltaE* values ranging from 0.1 to 1.3 up to 16.6 to 49.6. Yellow ochre had an effect only with 10% and 15% concentrations of kaolin powder calcined, increasing the value of Delta E* to greater than 1.0. Burnt sienna had an effect only with a 15% concentration of kaolin powder calcined, increasing the value of Delta E* at 300 and 450 kJ/m(2) to greater than 11.0. At the 5% concentration, kaolin powder calcined had the smallest color changes, followed by, in order, dry pigment titanium white, Artskin white, and Georgia kaolin. At the 10% concentration, Artskin white had the smallest color changes, followed by, in order, dry pigment titanium white, kaolin powder calcined, and Georgia kaolin. At the 15% concentration, Artskin white again had the smallest color changes, followed by, in order, dry pigment titanium white, Georgia kaolin, and the kaolin powder calcined. The smallest color changes in each kaolin group were at the 10% concentration for Artskin white, dry pigment titanium white, and kaolin powder calcined and at the 5% concentration for Georgia kaolin. CONCLUSIONS: Mixing dry earth cosmetic pigments with opacifiers did not protect silicone A-2186 from color degradation over time, especially in the case of red pigment. The group in which pigments were mixed with 10% Artskin white had the smallest color changes over time, followed by, in order, the groups in which pigments were mixed with 10% dry pigment titanium white, 10% kaolin powder calcined, and 5% Georgia kaolin. Red pigment had a significant effect on all opacifiers, especially Georgia kaolin and kaolin powder calcined. Yellow ochre and burnt sienna had an effect only on 15% kaolin powder calcined. Among all the pigment groups tested, yellow ochre remained the most color stable over time.  相似文献   
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无鼾老年人上气道及周围结构矢状面测量分析   总被引:2,自引:0,他引:2  
目的建立无鼾正常老年男女性上气道及周围结构矢状面52项测量项目的正常值范围并作比较。方法摄取无鼾正常老年男性38名、女性18名的X线头颅定位侧位片,测量分析上气道及周围结构52项测量项目,行统计学t检验。结果建立两组人群上气道及周围结构矢状面52项测量项目的正常值范围,老年男性上气道矢状面较宽,软腭、舌体较大,但软腭、舌体占口咽腔比例、上下颌骨关系、下颌平面角、软腭及舌的倾斜度、下气道咽后壁厚度两组差异无显著性。结论老年男女人群上气道及周围结构矢状面不尽相同,老年女性上气道矢状面宽度较男性窄。  相似文献   
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Previous research with other ethnic minorities has shown that culture and age cohort, as well as language and economic limitations, act as barriers to obtaining dental care and maintaining good oral health. This study compared self-reported oral health attitudes, self-efficacy, and dental practices of 20 younger and 23 elderly Korean-Americans. Oral assessments were also conducted to determine plaque and gingival status, and root and coronal caries. Significant differences emerged in health self-efficacy (P less than .01) and preventive health orientation (P less than .002). Elderly had fewer teeth (P less than .0001), more decayed and filled root surfaces (P less than .05 and P less than .004, respectively), and more decayed and filled coronal surfaces (P less than .001 and P less than .03). Both groups showed higher levels of distal and mesial plaque than occlusal and cervical plaque; however, the elderly had higher rates of both (P less than .0001). Gingival status was also worse for the elderly, on distal and mesial (P less than .01), facial (P less than .01), and lingual (P less than .01) surfaces. These differences are striking, since the elderly reported visiting the dentist more recently (P less than .0001); but most of these visits were for prosthodontic and emergency care. Better preventive dental care and education are necessary for elderly immigrants who have not been exposed to preventive dentistry in their home countries.  相似文献   
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BackgroundThe authors conducted a study to assess recent trends in dental care provider mix (type of dental professionals visited) and service mix (types of dental procedures) use in the United States and to assess rural-urban disparities.MethodsData were from the 2000 through 2016 Medical Expenditure Panel Survey. The sample was limited to respondents who reported at least 1 dental visit to a dental professional in the survey year (N = 138,734 adults ≥ 18 years). The authors estimated rates of visiting 3 dental professionals and undergoing 5 dental procedures and assessed the time trends by rural-urban residence and variation within rural areas. Multiple logistic regression was used to assess the association between rural and urban residence and service and provider mix.ResultsA decreasing trend was observed in visiting a general dentist, and an increasing trend was observed in visiting a dental hygienist for both urban and rural residents (trend P values < .001). An increasing trend in having preventive procedures and a decreasing trend in having restorative and oral surgery procedures were observed only for urban residents (trend P values < .001). The combined data for 2000 through 2016 showed that rural residents were less likely to receive diagnostic services (adjusted odds ratio [AOR], 0.82; 95% confidence interval [CI], 0.72 to 0.93) and preventive services (AOR, 0.87; 95% CI, 0.78 to 0.96), and more likely to receive restorative (AOR, 1.11; 95% CI, 1.02 to 1.21) and oral surgery services (AOR, 1.23; 95% CI, 1.11 to 1.37).ConclusionsAlthough preventive dental services increased while surgical procedures decreased from 2000 through 2016 in the United States, significant oral health care disparities were found between rural and urban residents.Practical ImplicationsThese results of this study may help inform future initiatives to improve oral health in underserved communities. By understanding the types of providers visited and dental services received, US dentists will be better positioned to meet their patients’ oral health needs.  相似文献   
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