Prosthetic reconstruction of dentitions seriously compromised by periodontal disease

Dentitions seriously compromised by periodontal disease are often in need not only of cause-related periodontal therapy of high quality but also of relevant prosthetic rehabilitation. Contrary to traditional claims, clinical investigations published during the last 2 decades demonstrate that, if adequately treated and controlled, such dentitions can carry fixed, cross-arch bridges on an extremely reduced amount of periodontium, with a good long-range prognosis. It has also been shown that a markedly reduced but healthy and favourably distributed periodontium supporting such constructions can withstand occlusal forces of considerable magnitude. Another controversial topic, related to fixed bridges, involves indications and contra-indications for cantilever segments. Some clinical investigations demonstrate a markedly increased risk of failure if the fixed bridge is provided with cantilever units, while other controlled studies with defined specifications on the design of the constructions exhibit a high success rate after 8 years or more also for bridgework where 2 or 3 cantilever units are included. The force pattern along cantilever segments of both tooth-supported and implant-supported bridges has been extensively studied. The results show that the force distribution depends not only on the occlusal contact pattern and the dimensioning of the cantilever beam, but also on the type of prosthetic construction in the opposite jaw occluding with the cantilever segment. The free-standing, implant-supported bridge has recently become an important treatment modality for rehabilitation of the partially edentulous jaw, and follow-up studies demonstrate a high success rate.(ABSTRACT TRUNCATED AT 250 WORDS)     

固定烤瓷桥的咀嚼效能比较研究

目的评价固定烤瓷桥修复后牙列缺损的咀嚼功能及患者的满意度。方法以健侧作为对照,采用重量法测定25例患者固定烤瓷桥修复侧的咀嚼效能,同时对患者修复后咀嚼功能的满意度进行问卷调查,分析患者固定烤瓷桥修复侧的咀嚼效能与其咀嚼功能问卷调查得分的相关性。结果局部固定烤瓷桥的咀嚼效能与同一患者天然牙相比有统计学差异(P<0.01),患者对固定桥修复的咀嚼功能作出了肯定的回答,但咀嚼效能的测试与患者的主观评分并不相关。结论同一患者的固定烤瓷桥修复较其相应天然牙的咀嚼效能有所降低。但绝大多数患者对固定烤瓷桥修复表示满意,患者对咀嚼功能的主观满意度可能受到诸多因素的影响。     

The condition of the soft tissues at tooth and fixture abutments supporting fixed bridges A microbiological and histological study.

In 10 partially edentulous patients provided with fixed bridgework supported by the combination of tooth and titanium fixture abutments, the condition of the soft tissues surrounding the abutments was examined. Sampling of supra- and subgingival plaque was performed from both teeth and fixtures. The samples were analyzed regarding the total bacterial counts, the relative distribution of bacterial morphotypes and the cultivable microflora. From each patient, soft tissue biopsies were obtained from 1 tooth and 1 fixture abutment, and the specimens were analyzed for the presence and extension of inflammatory cell infiltrates. The microbiological examination showed that the distribution of bacterial morphotypes in the supra- and subgingival plaque both at teeth and fixtures were similar, irrespective of localization and type of abutment. Nonmotile rods dominated the microflora, whereas spirochetes were either not detected or occurred in very low proportions. From the histological analysis, it was found that a majority of the soft tissue biopsies (75-80%) from both tooth and fixture sites contained only very small inflammatory cell infiltrates.     

Large mucosal bridges

An unusual case of colonic mucosal bridges in a patient with ulcerative colitis was demonstrated by double-contrast barium enema and confirmed at colonoscopy. We believe this to be the first report of this entity in the radiologic literature. The probable etiology of this uncommon manifestation of chronic inflammatory bowel disease is discussed.The opinions or assertions contained herein are the private views of the authors and are not to be construed as reflecting the views of the Department of the Army or the Department of Defense     

PBDE-47对人神经母细胞瘤SH-SY5Y细胞致突变作用

背景与目的:探讨2,2',4,4'-四溴联苯醚(2,2',4,4'-tetrabromodiphenyl ethers,PBDE-47)对人神经母细胞瘤SH-SY5Y细胞的致突变作用.材料与方法:设空白对照组、溶剂对照组、3个不同BDE-47剂量的试验组(1 μg、2 μg、4 μg/ml)和阳性对照组(MMC),共6组.SH-SY5Y细胞分别暴露于各组不同受试物24 h后,采用胞质分裂阻断法测定微核率、核浆桥率. 结果:PBDE-47可诱导SH-SY5Y细胞核分裂指数呈剂量依赖性下降,微核细胞率和核浆桥率呈剂量依赖性增加;2 μg/ml和4 μg/ml的染毒剂量可引起SH-SY5Y细胞核分裂指数明显降低(P＜0.05)以及微核细胞率和核浆桥率的明显增加(P＜0.05),而仅在4 μg/ml PBDE-47染毒组发现微核率明显增加(P＜0.05).结论:PBDE-47可诱导SH-SY5Y细胞微核和核浆桥的形成,具有致突变作用.     

Seismic Assessment and Retrofitting of Existing Road Bridges: State of the Art Review

The load-carrying capacity assessment of existing road bridges, is a growing challenge for civil engineers worldwide due to the age and condition of these critical parts of the infrastructure network. The critical loading event for road bridges is the live load; however, in earthquake-prone areas bridges generally require an additional seismic evaluation and often retrofitting in order to meet more stringent design codes. This paper provides a review of state-of-the-art methods for the seismic assessment and retrofitting of existing road bridges which are not covered by current design codes (Eurocode). The implementation of these methods is presented through two case studies in Croatia. The first case study is an example of how seismic assessment and retrofitting proposals should be conducted during a regular inspection. On the other hand, the second case study bridge is an example of an urgent assessment and temporary retrofit after a catastrophic earthquake. Both bridges were built in the 1960s and are located on state highways; the first one is a reinforced concrete bridge constructed monolithically on V-shaped piers, while the second is an older composite girder bridge located in Sisak-Moslavina County. The bridge was severely damaged during recent earthquakes in the county, requiring urgent assessment and subsequent strengthening of the substructure to prevent its collapse.     

烤瓷冠桥修复后1年的牙周情况分析

目的：观察烤瓷冠桥修复体对牙周组织的影响。方法：对126例患的336颗牙分别经镍铬合金烤瓷、贵金属烤瓷和铸造全瓷冠桥修复后1年进行复查，观察修复前后牙龈色泽、牙龈指数、菌斑指数、和牙周探诊深度的变化。结果：有14％的镍铬合金烤瓷修复后1年牙龈发生变色，贵金属烤瓷和铸造全瓷对牙龈色泽影响很少或没有；镍铬合金烤瓷和贵金属烤瓷修复后牙龈指数与术前有显性差异；铸造全瓷组术前和术后无明显差异；3组术前、术后的菌斑指数、牙周探诊深度无明显差异。结论：铸造全瓷牙修复对牙周组织的影响较少。     

3.5%尿素交连明胶致血浆组织胺浓度变化及其预防

目的：观察３．５％尿素交连明胶（ＵＧ）输入人体后血浆组织胺浓度物变化及Ｈ１和Ｈ２受体拮抗药（异丙嗪与法墓替丁）的预防效应,方法：６０例患者随机分为三组,每组２０例,Ⅰ、Ⅱ组分别输注林格氏液、３．５％ＵＧ各５００ｍｌ;Ⅲ组静注异丙嗪１２．５ｍｇ和法莫替丁２０ｍｇ后输液同Ⅱ组,分别于输液前、开始输液后１０、２０及３０分钟抽取血样一次检测血浆组织胺逍度,结果：Ⅰ组血浆组织胺浓度与输注林格氏液前比较在２０