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81.
Although chlorhexidine has been widely used in the prevention and treatment of gingivitis, its effects on taste sensation have not been well studied. The purpose of the present study was to evaluate taste alterations following regular applications of 0.2% chlorhexidine mouthrinses. 24 healthy and non-smoking clinical instructors, dental assistants and dental students were divided into 3 groups after having reached a status of clinical gingival health by 4 weeks of supervised oral hygiene procedures. Following this, they were asked to abolish all mechanical oral hygiene for a period of 14 days, during which time they rinsed twice daily with different mouthrinses. Group A rinsed with a 0.2% chlorhexidine solution, group B served as control and utilized a 0.001 molar solution of quinine hydrochloride as a placebo rinse. A second control group (C) rinsed with distilled water. At days -3 and -2, as well as at days 1, 2, 13 and 14 of the experimental period, and 1 and 2 days after cessation of the rinsing, taste sensitivity was evaluated by a magnitude estimation, suprathreshold scaling procedure for the 4 taste qualities--sweet, salty, sour and bitter. 6 different concentrations of each of sucrose, sodium chloride, citric acid and quinine hydrochloride were utilized. Magnitude estimations of the perceived intensities of each series of test solutions were calculated. The analysis of co-variance revealed significant differences at the short-term and treatment-related suprathreshold scaling responses between both control groups (B, C) and the test group (A) for the sodium chloride magnitude estimation function. However, no significant inter-group differences in the magnitude estimation function were found for the remaining taste qualities.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
82.
微型pH电极直接测试人牙菌斑pH的应用研究   总被引:6,自引:1,他引:6  
目的:进一步探讨微型pH电极在原位检测人牙菌斑pH的可行性,了解漱糖后对菌斑pH的影响。方法:采用微型蜂式pH指示电极直接测试人牙邻面菌斑pH变化。结果:微型pH电极与玻璃pH大电极所测结果基本一致;漱糖后菌斑pH呈下降趋势,20min时达到最低点;无龋组与龋敏感组之间的pH改变无显著性差异。结论:微型pH电极适用于在原位直接测试菌斑pH;漱糖后菌斑pH发生改变,但龋坏与否的个体之间未见明显不同  相似文献   
83.
It has become increasingly recognized that groups of microorganisms interact within the subgingival plaque of adult subjects with periodontitis. It is much less clear, however, whether the consortia of microorganisms associated with periodontitis are different in early and more advanced cases of periodontitis. To investigate this point further, subgingival plaque was collected from six sites in 87 adolescents with periodontitis and 73 controls and the samples were analyzed for the detection of 18 microbial species using the DNA-DNA hybridization technique. Actinomyces oris accounted for the highest proportion of the flora and was more predominant among controls. Prevotella nigrescens, Prevotella intermedia, Porphyromonas gingivalis, and Tannerella forsythia were present at higher levels among the subjects with periodontitis. Factor analyses identified one factor characterized by highly positive loadings for T. forsythia, Campylobacter rectus, P. gingivalis, P. intermedia, P. nigrescens, Parvimonas micra, and Treponema denticola, and another factor characterized by highly positive loadings of A. oris, Capnocytophaga ochracea, Eikenella corrodens, Streptococcus intermedius, Selenomonas noxia, Streptococcus oralis, Streptococcus sanguinis, and Veillonella parvula. Aggregatibacter actinomycetemcomitans and Streptococcus mutans did not load on any of the two factors, while Fusobacterium nucleatum loaded on both. These findings confirm the occurrence of clustering of subgingival bacteria according to case status also among young individuals.  相似文献   
84.
OBJECTIVE: P-113, a 12 amino acid histatin-based peptide, was evaluated in a mouthrinse formulation for safety and efficacy in a phase 2 multi-center clinical study. METHOD: 294 healthy subjects abstained from oral hygiene procedures and self-administered either 0.01% P-113, 0.03% P-113 or placebo mouthrinse formulations twice daily over a 4-week treatment period. During this time, the safety, anti-gingivitis, and anti-plaque effects of P-113 were evaluated. RESULTS: There was a significant reduction in the change from baseline to Day 22 in bleeding on probing in the 0.01% P-113 treatment group of the intent to treat population (p=0.049). Non-significant trends in the reduction of the other parameters were observed in this population (p> or =0.159). A sub-group of subjects which developed significant levels of disease within the four-week timeframe of the study was identified based on baseline gingival index scores > or =0.75. Significant findings were observed for bleeding on probing, gingival index and plaque index within this population (p<0.05). There were no treatment-related adverse events, and there were no adverse shifts in supragingival microflora during the study. Significant amounts of the peptide were retained in the oral cavity following rinsing. CONCLUSION: These data suggest that P-113 mouthrinse is safe and reduces the development of gingival bleeding, gingivitis and plaque in the human experimental gingivitis model.  相似文献   
85.
DNA probe detection of periodontopathogens in advanced periodontitis   总被引:4,自引:0,他引:4  
Species-specific DNA probes were used to determine the presence of Actinobacillus actinomycetemcomitans (A.a.), Porphyromonas (Bacteroides) gingivalis, Prevotella intermedia, Treponema denticola. Eikenella corrodens, Fusobacterium nucleatum , and Wolinella recta in subgingival plaque from deep pockets/sites of patients with advanced periodontitis. The subjects were 20 patients with severe adult periodontitis, 13 men and 7 women (mean age 45.6 ± 6.7 yr). For each subject, 9–10 subgingival sites with the deepest probing depths from each quadrant were sampled by the paper point method, a total of 198 sites, with mean probing depth 7.2 ± 1.6 mm and clinical attachment level 9.5 ± 2.7 mm. A.a . was present in at least one site in 75% of the subjects; P. gingivalis was found in 95%; P. intermedia and W. recta were found in 90%, respectively; and T. denticola, E. corrodens , and F. nucleatum were found in all subjects. In the 198 samples, A.a . was detected in 25.8%, P. gingivalis in 51.5%, P. intermedia in 64.1%, T. denticola in 60.6%, E. corrodens in 72.9%, F. nucleatum in 74.7%, and W. recta in 65.7%. The predominant combination was the simultaneous presence of P. intermedia, T. denticola, E. corrodens, F. nucleatum , and W. recta in 89.5% of the subjects and 46.8% of the sites. Of these sites, 51.1% showed the combined presence of P. gingivalis and 28.4% that of both A.a . and P. gingivalis . None of the seven bacteria could be detected in 14.4% of the total sites sampled. The present study indicates that severe destructive adult periodontitis is a multibacterial infection and that certain combinations of periodontopathogens seein to be important in the pathogenesis of the disease.  相似文献   
86.
老年根面龋临床初步分析   总被引:11,自引:0,他引:11  
目的:分析老年人根面龋发病的危险因素,为根面龋防治选择最佳方法.方法:对门诊老年人根面龋患者的临床资料进行分析.结果:牙龈萎缩、菌斑指数、年龄、吃甜食习惯与根面龋有关,随年龄增大而根龋增加且多发于下颌磨牙、前磨牙,以近远中面为好发牙面.结论:牙龈萎缩、菌斑指数、年龄是根龋发生的危险因素.防治老年根面龋应消除各种致病因素,早期防治,以保护天然牙列的完整性.  相似文献   
87.
The purpose of this study was to examine the effectiveness of a dental health education program providing dental health information and toothbrushing instruction on oral cleanliness. Two methods of instruction, individual and group instruction, are presented in this study. The plaque situation was assessed in a group of 175 children, 11-14 years of age, by the Patient Hygiene Performance (PHP) method at the beginning of the study and at 1, 2, and 12 months. It was found that immediately after instruction the dental health education program resulted in improved oral hygiene home care for the two experimental groups. However, the improvement noted was achieved regardless of the method of toothbrushing instruction (individual versus group). Moreover, it was demonstrated that maintenance of a satisfactory level of oral hygiene home care was dependent upon review of educational programs and toothbrushing instruction and not related to the method of instruction.  相似文献   
88.
目的:探讨口腔龈下菌斑中血链球菌、中间普氏菌与冠心病的关系。方法:检查与记录60例研究对象(冠心病组与对照组各30例)的牙龈指数(GI)、菌斑指数(PLI)、牙周袋探诊深度(PD)。应用生化法检测两组研究对象龈下菌斑中的血链球菌数,并用定性随机引物酶链反应法对两组研究对象龈下菌斑中的中间普氏菌进行了鉴定。结果:冠心病组的PD、PLI和龈下菌斑中的血链球菌数及中间普氏菌检出率明显高于对照组(P(0.05)。结论:冠心病组的牙周健康状况相对更差,与冠心病有关的口腔细菌除血链球菌外,龈下菌斑中的中间普氏菌也与冠心病的发病关系密切。  相似文献   
89.

Background

Helicobacter pylori is a Gram-negative microorganism which is able to colonize the gastric mucosa and is associated with peptic ulcer, gastric carcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Several studies have detected this bacterium in the oral cavity, suggesting it as a potential reservoir. The aim of this study was to investigate the presence of H. pylori in the oral cavity of individuals with periodontal disease and gastric diseases.

Methods

115 individuals, with mean age 49.6 (±5.8) years, were divided in 4 groups: (A) with gastric diseases and periodontal disease; (B) with gastric diseases and no periodontal disease; (C) without gastric diseases and without periodontal disease, (D) without gastric diseases and with periodontal disease. Supra and subgingival plaque samples were collected from posterior teeth of the individuals with sterile paper points, and prepared for Polymerase Chain Reaction analysis. Fisher's exact test was used for detecting statistical differences between groups (p < 0.05).

Results

H. pylori was detected in supragingival plaque of 9/36 (25%) of group A, 1/31 (0.3%) of group B, 0 (0%) of group C and 3/36 (8.3%) of group D. No subgingival samples were positive for H. pylori. There was a statistically higher prevalence of H. pylori in groups A and D when compared to B and C (p < 0.05).

Conclusion

H. pylori was detected in the supragingival plaque, but not in the subgingival plaque, of individuals with periodontal disease and upper gastric diseases. There was an association between the supragingival colonization of H. pylori and oral hygiene parameters such as the presence of plaque and gingival bleeding.  相似文献   
90.
木糖醇牙膏对菌斑抑制效果的临床试验   总被引:2,自引:0,他引:2  
目的:评价木糖醇牙膏在抑制菌斑生成的临床效果。方法: 60名军校学员随机分为3组,即黑妹木糖醇牙膏组、黑妹空白牙膏组、高露洁全效牙膏组,双盲法评价1周和4周后的刷牙效果。结果:使用木糖醇牙膏4周后,试验组全口平均菌斑指数持续下降,第4周与第1周比较P<0. 01。1周后,三组菌斑清除率无显著性差异; 4周后,黑妹木糖醇牙膏组平均菌斑清除率最高。黑妹木糖醇牙膏组与高露洁全效牙膏组菌斑清除率无显著性差别,而与黑妹空白牙膏组比较有显著性差异。结论:长期使用木糖醇牙膏能显著抑制牙菌斑形成,黑妹木糖醇牙膏与高露洁全效牙膏抑菌效果相当,均优于不含木糖醇的空白牙膏。  相似文献   
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