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21.
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   
22.
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   
23.
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   
24.
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   
25.
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   
26.
Atraumetic Restorative Treatment (ART) has been adopted around the world to avoid unnecessary extractions, especially in non-industrialized countries The development of specific glass ionomer cements marketed for the ART technique has contributed to the technical success rate. In this study. Ketac-Molara (3M ESPE. Dental Medzn Germany) was used to restore 150 Class I cavities in 118 Brazilian public school children, aged from 7–12 years. At baseline and at subsequent recalls. CPI probes with a ball-end of 0.5 millimeters (mm) were used to assess loss of restorative material, and photographic color transparencies of restorations were made. After six months. 83 patients returned for follow-up examinations, with 71.8% of their restorations designated as acceptable. After three years. 49 patients with 57 ART-restorations were evaluated, with 21.0% of these restorations graded as acceptable Another 29.8% of their restorations had been replaced by more permanent materials. The main objective of the ART technique is tooth retention; this was achieved for 94.7% of the restored teeth in a high caries risk population who returned for recalls.  相似文献   
27.
Endoscopically controlled sinus floor augmentation. A preliminary report.   总被引:1,自引:0,他引:1  
Sinus augmentation has been advocated to be a surgical technique with predictable results in peri‐implant surgery. Endoscopic surgery of the maxillary sinus so far has been used as diagnostic procedure. In this paper, the use of endoscopy is described as a low invasive adjunctive technique in sinus floor augmentation. After preparation of the mucoperiosteum, bone grafts can be placed under endoscopic control between sinus floor and mucoperiosteum. A laterobasal approach via a small osteotomy and a transalveolar approach are possible for mucosal elevation and graft placement. First clinical results are reported. Endoscopic sinus lift may contribute to a reduction of perioperative morbidity, reduction of oroantal fistulae and control of graft position. The less invasive technique may allow to extend the indication for sinus augmentation.  相似文献   
28.
It has previously been reported that porous‐coated root form endosseous dental implants, became well integrated when used in the traditional 2‐stage surgical approach. In this study, the placement of the implant in a 1‐stage (non‐submerged)technique was to be explored. Implants were placed in the mandibles of dogs, and 2 designs were used differing only in that one (experimental) had a 3mm transgingival extension, permitting it to be exposed lo the oral cavity from the outset. 12 (3 per animal) non‐submerged implants were placed on I side of 4 beagle dogs and 12 control (submerged) implants were placed contralaterally. All implants were allowed to heal for 6 weeks, after which histological preparations were made. 2 of 12 non‐submerged implants were lost due to post‐operative complications: otherwise, all implants healed uneventfully. Histomorphometric analysis revealed bone‐implant contact, as assessed by absolute bone contact (ABC) and contact length fraction (CLF). to be greater for the submerged design, suggesting that bone healing may be delayed with the non‐submerged approach. As well. at this early stage of healing, for both implant designs, ABC and CLF were significantly greater on proximal than on buccal and lingual aspects.  相似文献   
29.
The visit of Dr. Trendley Dean to Dublin in the mid-1950s helped accelerate the decision to introduce water fluoridation as a public health measure in the prevention of caries in the Republic of Ireland. A challenge to the constitutional validity of the Health (Fluoridation of Water Supplies) Act 1960 failed and in 1964 the water supplies of Dublin city were fluoridated. Over the next seven to eight years all the major urban communities in the Republic of Ireland were fluoridated. Currently, 67 percent of the 3.5 million people in the country reside in fluoridated communities. Studies conducted over the last 20 years show that residents of fluoridated communities have better dental health than those in nonfluoridated communities—the mean dmft is lower in children and the number of natural teeth present in adults is higher.  相似文献   
30.
A significant minority of medical and dental students fail their undergraduate courses. Early warning systems (EWSs) have been developed in some areas of higher education to predict 'at-risk' students at an early remedial stage. An attempt is made to develop an EWS to predict failure in the bacteriology component of the Batchelor of Dental Surgery course at Manchester Dental School. A system based on class tests and previous end-of-year performance is derived which is used to predict those students likely to fail or fall in the bottom 20-25% in their finals examination. The predictors are combined by a simple equal weights method, which is found to have the same predictive power as using multiple regression. Failure was correctly predicted in 60% of cases, at the expense of 71% false alarms. The high number of false alarms reflects the low failure rate rather than the lack of predictive information. The need for effective cross-validation of EWSs is discussed; many previous studies have not been tested on independent data.  相似文献   
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