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81.
Sj?gren's syndrome is an auto-immune disease involving exocrine glands causing amongst others xerostomia and dry eyes. Many other tissues may be affected as well. Early recognition of this disease may help to alleviate signs and symptoms and is, thus, important. The aim of this paper is to provide the dentist with knowledge to enable him to timely diagnose the oral component of Sj?gren's syndrome as well as to give guidelines for the treatment.  相似文献   
82.
The transport of ionic and non-ionic compounds through bovine dental enamel was measured before and after irradiation with a carbon dioxide laser (energy density 10J/cm2). The irradiation increased the permeability of enamel rather than decreased it as postulated by other workers to explain the increased resistance to surface demineralization produced by such irradiation.  相似文献   
83.
Of the group of dentate adults taking part in the Public Health insurance scheme, 78% has opted for a supplementary insurance for dental care after the dental health care reform on January 1, 1995. For edentulous people this figure is 33%. Both for people who choose for a supplementary insurance and for those who did not, financial motives were most important. For the dentates visiting a dentist regularly, the time period between two check-ups has grown from 6.0 months to 6.9 months. The extent to which check-ups are postponed is not different for people with or without a supplementary insurance for dental care.  相似文献   
84.
Plasma antibody levels in periodontitis patients and controls   总被引:2,自引:0,他引:2  
BACKGROUND: A major aspect of the adaptive host response in periodontitis is the production of antibodies. Several risk and susceptibility factors for periodontitis, including smoking, age and composition of the subgingival microflora, have also been suggested to influence antibody production. AIM: The present study was conducted to investigate plasma levels of immunoglobulin (Ig) G, A and M antibodies in periodontitis patients of Caucasian European heritage in relation to disease severity, smoking, diagnosis and prevalence of periodontopathogens. METHODS: In this study, 29 patients with severe periodontitis, 51 with moderate periodontitis and 55 controls without periodontal destruction were enrolled. From the total of 80 patients, 18 were diagnosed with aggressive periodontitis and 62 with chronic periodontitis. Total IgG, IgA and IgM as well as IgG isotypes were analyzed in plasma samples. RESULTS: Levels of total IgG, IgA and IgM were not different between patients and controls; however, in periodontitis, higher levels of IgG1 and IgG2 were observed. Smoking appeared to be significantly and inversely related to antibody levels in periodontitis, in particular for total IgG and IgG2. The absence of an elevated total IgG and IgG2 in smoking patients was irrespective of severity, prevalence of periodontal pathogens and diagnosis. The elevation of total IgG and IgG1 and IgG2 in non-smoker periodontitis patients was observed in patients with moderate periodontitis and even greater in patients with severe periodontitis, but was independent whether patients were infected with Actinobacillus actinomycetemcomitans or Porphyromonas gingivalis and independent of diagnosis. Clinically, it was observed that patients who smoked had more periodontal bone loss; the current findings on antibody levels may be one of several mechanisms related to more extensive periodontal breakdown in smoker patients. CONCLUSION: The current study shows that non-smoker periodontitis patients have higher levels of total IgG and IgG2 than smoker periodontitis patients.  相似文献   
85.
Background: The replacement of a single tooth or several teeth by means of single‐implant restorations is an increasingly used method that needs long‐term validation. Purpose: The goal of this study was to evaluate the outcome of single‐implant restorations by means of fixed restorations and to define the prognosis through marginal bone level estimations. Materials and Methods: From November 1986 to June 1998, 270 Brånemark implants (215 in the upper jaw) were installed in 219 patients (106 males). Both anterior and posterior sites were involved. Of the 263 single restorations, 28 were placed in private dental offices. The patients were followed until June 1999. Results: Twelve implants failed before or at abutment connection or within 6 months afterward. Only four implants failed later. The cumulative success rates were 93% for the implants and 96.5% for the restorations over a period of 11 years. The marginal bone loss during the first 6 months after abutment connection reached 0.71 mm and then dropped to 0.036 mm annually over a period of 10 years. Conclusions: Single‐implant restorations (Brånemark System) are a reliable treatment with a good long‐term prognosis. Failures were concentrated during the healing period and early loading phase.  相似文献   
86.
The periodontal bacteria Prevotella intermedia and Prevotella nigrescens have been recently separated from each other. The purpose of this study was to investigate the distribution and routes of transmission of these bacteria among family members. Seven patients with moderate to severe periodontitis were selected. These probands, their spouses and 14 of their children were investigated. The presence of Pr. Intermedia and Pr. nigrescens was determined by culture techniques in pooled subgingival plaque samples, in the saliva, on the tongue, tonsils and buccal mucosa. Differentiation of Pr. intermedia and Pr. nigrescens was performed by enzyme electrophoretic mobility. From all 7 patients, as well as 4 spouses and 3 of the children, Pr. intermedia could be isolated. Pr. Nigrescens was found in 2 of the 7 patients, in 5 of the spouses and in 5 of the 6 children aged 5–10 yr. In the 8 children aged 0–4 yr both species were seldom isolated. These data are in accordance with earlier findings that Pr. Intermedia is associated with periodontitis and Pr. Nigrescens with a relatively healthy periodontal condition. Ribotyping of bacteria was performed by hybridization of Hindlll restriction endonuclease digests of chromosomal DNA with ribosomal DNA. Isolates from unrelated individuals always had distinct ribotypes. Indistinguishable ribotypes of Pr. intermedia and Pr. Nigrescens were found both among married couples and among parents and children. This indicates that intrafamilial transmission of Pr. intermedia and Pr. Nigrescens is possible both between adults and between parents and children.  相似文献   
87.
Ninety-one consecutive edentulous patients who had been treated by means of fixed prostheses (n = 103) supported by Br?nemark implants (n = 589) were examined. Eighteen fixtures (3%) failed to integrate. After a mean loading time of 32 (range 6 to 80) and 38 months (range 5 to 83) for fixtures in the maxilla and mandible, respectively, an additional 12 fixtures lost integration. The cumulative failure rate for individual fixtures after 6 years was 8.4% and 5% for maxillae and mandibles, respectively. Only one patient had to revert to complete dentures. For fixtures in the maxillae, the mean marginal bone loss was 0.7, 0.1, and 0.2 mm for each of the first 3 years of loading, respectively; for fixtures in mandibles, the corresponding values were 0.7, 0.2, and 0.1 mm. The loss in marginal bone height was equal in both jaws and was not related to bleeding on probing or to the preoperative resorption anatomy.  相似文献   
88.
Eighty-six consecutive patients, provided with 84 resilient and two nonresilient overdentures (six in the upper and 80 in the lower jaw), were examined. The overdentures were supported by a total of 173 osseointegrated titanium fixtures (the standard Branemark abutment), with a mean loading time of 19.1 months (range 4 to 48 months). In each jaw only two fixtures anchored the overdentures. No failures occurred during the observation period but two fixtures were lost before loading. The radiographic annual bone loss around fixtures in the lower jaw was -0.8 mm for the first year and less than -0.1 mm for the following years. The change in marginal bone height did not correlate with parameters such as the occlusion and articulation pattern, the presence or absence of a soft liner around the abutments, and the magnitude of the interabutment distance. The patients' reactions to overdenture treatment were, on the whole, positive concerning chewing function, phonetics, and comfort. The need for maintenance care of the clip-bar attachment was minimal.  相似文献   
89.
In this study, a mouthrinse containing calcium lactate was tested for its effect on the accumulation of dental plaque and on the concentrations of calcium and phosphorus therein. Human volunteers rinsed four times per day with a calcium lactate (165 mmol/l) solution for 1 week. Plaque samples, collected 16 h after the last rinse, were analyzed chemically. Calcium lactate rinses had no effect on the plaque score, but resulted in approximately twofold increases of calcium and phosphorus in plaque. The incorporation of monofluorophosphate (5 mmol/l) into the rinsing solution failed to show any significant influence on calcium, phosphorus, and fluoride levels in plaque. Increased mineral deposition in the plaque may provide an explanation for the reduced caries development earlier observed in rats fed a diet containing calcium lactate.  相似文献   
90.
Eight dentists evaluated 72 proximal surfaces of premolars with respect to all caries lesions and to lesions into dentine in digital images from a storage phosphor plate system. The images were processed in four different ways: (1) the default algorithm of the standard imaging system (DF); (2) an algorithm correcting for attenuation and visual response (AV), and two proprietary caries-specific enhancement algorithms (3) K1, and (4) K2, respectively. The lesions were validated by histological examination. There were no significant differences in the areas under the receiver operating characteristic curves between differently processed radiographs for the categories of all caries lesions and caries into dentine.  相似文献   
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