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51.
Abstract: In order to evaluate the level of evidence of factors influencing the survival of reconstructions, systematic reviews of the relevant literature were prepared by a group of rapporteurs. The review papers were circulated to the members of the group before the conference and formed the basis for group and panel discussions. Subsequently, modifications were added to the review papers, and suggestions for consensus statements concerning the following topics were prepared and again critically reviewed in the group and in the plenum: Impact of (i) periodontal disease on the survival of tooth-supported reconstructions, (ii) post-surgical factors as supportive therapy on the survival of implant supported reconstructions, (iii) technical and/or biological complications on the survival of different types of reconstructions, (iiii) material choice for reconstructions on the survival of single crowns and fixed dental prostheses.  相似文献   
52.
An epidemiological survey of the oral health needs of 1144 elderly patients was conducted in hospitals and nursing homes in Western Australia. Patients were categorised as being either totally dependent (requiring intensive nursing care) or partially dependent (requiring nursing supervision). Of all patients the mean age was 80.2 yr, 70% were women, 74% were edentulous, and 70% needed some form of prosthetic care. Of all dentate patients 56% needed dental scaling (and 17% needed complex periodontal treatment), 47% needed some restorative treatment (with a mean need per patient of 1.1 coronal restorations and 0.4 radicular restoration), and 29% needed one or more dental extractions (with a mean need of 1.4 extractions per patient). Partially dependent patients had statistically significant higher needs for prosthetic work than did totally dependent patients, while the converse applied to extraction needs, but in all other aspects the needs of the two categories of patient did not differ significantly.  相似文献   
53.
Abstract – A total of 170 adult Tanzanians aged 30- 691 yr were examined for loss of attachment, gingival recession, plaque, calculus and gingival bleeding on all surfaces, of all teeth. The severity of loss of attachment varied considerably between tooth types. Irrespective of age, mandibular incisors and first and second molars were the teeth most affected by loss of attachment. In all age groups heavy plaque deposits and gingival bleeding occurred more frequently in posterior than in anterior teeth, Dental calculus was most frequently observed in the maxillary posterior and mandibular anterior teeth. The distribution of calculus within the dentition showed a close resemblance with the patterns of loss of attachment and gingival recession. The variation of the severity of periodontal breakdown within individuals indicates that the use of mean values to describe periodontal breakdown may give the impression of a greater uniformity than really exists.  相似文献   
54.
Studies using plaster models of teeth and photographs simulating the full range of occlusal conditions have found high agreement between measures of adolescent social acceptability of these conditions and perceived need for orthodontic treatment. This study examined the association between adolescents' acceptability of their own occlusal condition, severity of malocclusion, and likelihood of undergoing orthodontic treatment. The factors predicting the acceptability of occlusal condition of 13-yr-olds, as assessed by the SASOC scale, were measurements of acceptability of general physical appearance, and the severity of occlusal condition. Variability in SASOC scores appeared to be independent of gender, socioeconomic status, and ethnicity. Gender, and severity of occlusal condition were important differences between subjects who had received, planned, or were undergoing orthodontic treatment, and those who had not. Neither SASOC scores nor perceived need for treatment accounted for a significant proportion of the variance between these groups. Although adolescents seeking orthodontic treatment had a greater severity of malocclusion than those not, little difference was observed between these groups in acceptance of occlusal condition.  相似文献   
55.
电脑比配色仪与比色板之间的相近性分析   总被引:1,自引:0,他引:1  
目的:通过对比色记录的分析,比较Vita比色板、松风Vintage Halo比色板和电脑比配色仪之间的相近性和差异性。方法:随机抽取100名年龄在21~24岁的本地在校大学生,由男女两位测试者使用电脑比配色仪、Vita比色板和松风Vintage Halo比色板对被测试者的左上中切牙进行比色分析。结果:三种比色方法均以A色调最为集中,占总数的55%以上。其次是D色调占总数20%以上。男女测试者的选色在A、R、VR.系列中无明显差异。结论:电脑比配色仪、Vita比色板、松风Vintage Halo比色板均不能完全覆盖本地区青年天然中切牙的色度特征,只在A色调系列中重复率较高。  相似文献   
56.
武汉市3~5岁儿童牙齿酸蚀症的研究   总被引:4,自引:1,他引:3  
目的:调查武汉市3~5岁儿童的酸蚀症流行状况;评价儿童饮用饮料和饮食习惯、口腔卫生习惯与酸蚀症的关系。方法:随机抽样武汉市4所幼儿园3~5岁儿童共500人。对所有儿童进行酸蚀症和龋齿发病情况的临床检查以及问卷调查,问卷内容包括:儿童每天消耗饮料或食物的频率,以及口腔健康行为。收集酸蚀症儿童和无酸蚀症儿童各20人,对其唾液pH值、流速和缓冲能力进行测定和比较。结果:武汉市3—5岁儿童酸蚀症的患病率为9.3%。儿童睡觉时含奶瓶、喝饮料的习惯与酸蚀症的发生呈正相关。酸蚀症儿童和对照组儿童唾液分析结果无显著性差异。结论:预防酸蚀症应该减少酸性食物及饮料的消费量及频率。  相似文献   
57.
目的探讨保留齿状线加皮桥重建闭合切口治疗环状混合痔的可行性及疗效。方法治疗组选用保留齿状线加皮桥重建闭合切口32例,与对照组采用传统外剥内扎治疗34例在术后疼痛、水肿、出血、痔残留等并发症及住院时间、愈合时间等方面进行比较。结果治疗组在术后疼痛、水肿、出血、痔残留等及住院时间、愈合时间等方面均优于对照组。结论保留齿状线加皮桥重建闭合切口治疗环状混合痔安全、有效、可行。  相似文献   
58.
59.
Abstract  – The dental records made on presentation of 1367 consecutive patients (731 females and 636 males) for orthodontic treatment at a private orthodontic practice between 1998 and 2002 were examined for data relating to trauma to the permanent incisors. The results showed that 10.3% of these patients had suffered from dental trauma before the onset of orthodontic treatment. The highest prevalence of dental trauma was determined in the 11–15 years age group, corresponding to the dental developmental stage of the late mixed dentition. The most frequently affected teeth were the maxillary central incisors (79.6%), and the most common types of trauma were fracture of enamel–dentin without pulpal involvement (42.7%) and fracture of enamel (33.8%). Compared to patients with normal overjet and adequate lip coverage, the frequency of dental trauma was significantly higher in patients with increased overjet and adequate lip coverage ( P  = 0.028) or with increased overjet and inadequate lip coverage ( P  = 0.003). The results of the present study indicate that a significant percentage of candidates for orthodontic treatment, and especially those with increased overjet and inadequate lip coverage, suffer trauma to their permanent incisors before the onset of orthodontic treatment. It might also be concluded that preventive orthodontic treatment of such patients should be initiated and completed before the age of 11, i.e. in the early to middle mixed dentition.  相似文献   
60.
陈彬  刘宽  王伟 《卒中与神经疾病》2007,14(5):267-270,314
目的比较研究成年大鼠细胞周期蛋白依赖性激酶抑制因子在神经元和星形胶质细胞的表达差异。方法应用免疫荧光和激光扫描共聚焦显微镜观察成年大鼠生理状态下大脑皮层或海马CA1、CA3、DG区神经元和星形胶质细胞细胞周期蛋白依赖性激酶抑制因子(CDKI)p15Ink4b、p21cipl的表达。结果成年大鼠海马区和大脑皮层的神经元有p15Ink4b和p21cipl的表达,细胞核和细胞浆均有表达,且以胞核为主;星形胶质细胞也有上述细胞周期调控蛋白的表达,便细胞数目较少,并且表达这些指标的星形胶质细胞多聚集在海马区。结论成年大鼠大脑皮层和海马区的神经元和星形胶质细胞均表达p15Ink4b和p21cipl,而其在神经元的表达较星形胶质细胞更为普遍。  相似文献   
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