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181.
Objectives: (i) Initially, to devise and examine the validity of a system for determining lesion activity on root surfaces, and (ii) compare the effectiveness of two preventive programmes in controlling root caries in elderly people using the devised system. Materials and methods: (i) Four clinical variables: texture, contour, location and colour of root caries lesions were selected to evaluate lesion activity. The intraexaminer reproducibility of the scoring system was assessed on 28 elderly patients. The accuracy was assessed on 10 of these persons using an impression material (Clinpro, 3M ESPE). (ii) Of total, 215 homebound 75+ year olds were randomly assigned to one of three groups: group 1, once a month a dental hygienist brushed the teeth of the participants and applied Duraphat vanish to active root caries lesions. The participants in groups 2 and 3 received 5000 and 1450 ppm F‐toothpaste, respectively, to use twice a day. This study included an interview, a baseline examination and a final follow‐up examination after 8 months. Results: (i) Intraexaminer reproducibility of the root caries scoring system was 0.86 (Kappa). The sensitivity and specificity was 0.86 and 0.81. (ii) Data from those 189 (88%) who completed the study disclosed that there were no inter‐group differences at the baseline examination concerning relevant conditions. At the end of the study, the root caries status of participants in groups 1 and 2 had improved significantly when compared with group 3 (p < 0.02). No significant difference was observed between groups 1 and 2 (p = 0.14). Conclusion: The data suggest that the root caries scoring system is reliable. Both the intervention programmes controlled root caries development; the hygienist in eight of 10 persons, the 5000 ppm F‐toothpaste in seven of 10. In contrast, five of 10 participants who only brushed with 1450 ppm F‐toothpaste had root caries progression.  相似文献   
182.
Liu Y  Lin H  Bai Y  Qin X  Zheng X  Sun Y  Zhang Y 《Helicobacter》2008,13(4):256-260
Background: The aims of our study were to determine the presence of Helicobacter pylori DNA in the dental plaque of Chinese children aged 3–6 years by nested polymerase chain reaction (PCR) and to investigate the relationship between this infection and the occurrence of dental caries or oral hygiene index.
Methods: Two hundred and fourteen children from a kindergarten in Guangzhou City of China were evaluated. The children's plaques were assessed by plaque indices of Quigley–Hein. Dental plaque was analyzed using nested PCR for two sets of primers directed to the 860-bp fragment of H. pylori genomic DNA, which have been reported to be highly sensitive and specific by other researchers.
Results: H. pylori was detected in dental plaque samples from 126 children, and 70 children with dental caries carried H. pylori in dental plaque. Of these children without infection, only 36 of 88 suffered dental caries. Besides, the average dental plaque index of 126 H. pylori -positive children was higher than that of 88 children without infection. In the present study, there was a significant correlation between H. pylori infection and dental caries or dental hygiene.
Conclusion: The oral cavity may be a reservoir for H. pylori infection in children. H. pylori in dental plaque may play a role in the occurrence of dental caries, and poor oral hygiene may represent a risk factor for H. pylori in the oral cavity.  相似文献   
183.
Objectives: To quantify the adverse effects of the number of xerostomic medications on dental caries, oral mucosa, andperiodontal disease. Design: Secondary analysis of across‐sectional study of the Veterans Dental Study. Setting: Four New England area VA outpatient clinics. Subjects: The sample consists of 345 male veterans participating in The Veteran's Dental Study who also had pharmacy records. Main outcome measures: Oral health data included total surfaces of coronal caries, a modification of the root caries index, mean oral mucosa scores, and Community Periodontal Index of Treatment Need (CPITN). Oral health parameters were measured and recorded in clinical dental examinations. Exposures: Intake of xerostomic medications 14‐385 days prior to the dental examination. Statistical Analyses: The relationships between exposure and outcome were analyzed via linear and logistic regression methods adjusting for possible confounding factors such as disease burden index, alcohol consumption, dental care, and smoking status. Results: Veterans who were taking at least one xerostomic medication were almost three times more likely to have mean mucosa scores in the worst 25 percentile than veterans taking no xerostomic medications, OR= 2.63 (confidence interval [CI] 1.34,5.16, p=0.03) after adjusting for age, number of teeth, disease burden index, income, smoking and alcohol use. Participants who were taking at least one xerostomic medication experienced higher but non‐significant increases in coronal (OR =1.21; CI. 0.66, 2.25) and root caries (OR =1.10 CI. 0.54, 2.24) measured by numbers of total decayed surfaces. Conclusion: There were significant deleterious effects of xerostomic medications on oral mucosa. However, xerostomic medications do not appear to increase coronal caries, or periodontal index measured by CPITN among ambulatory, community dwelling participants who were able to perform routine preventive oral care.  相似文献   
184.
We compared the anticariogenic effect of lactobacilli expressing a single-chain antibody (scFv) against the SA I/II adhesin of Streptococcus mutans under the control of an inducible or a constitutive promoter. Both lactobacilli expressed equal amounts of scFv and agglutinated S. mutans bacteria expressing SA I/II to a similar level. In a rat caries model, transformed lactobacilli could be detected in the oral cavity throughout the duration of the study. Transformants containing the constitutive promoter were slightly more protective than those containing the inducible promoter suggesting that continuous in situ production of scFv in the oral cavity may be therapeutically superior to intermittent production.  相似文献   
185.
Objective: This study aimed to examine the possible association between level of education and 5‐year caries increment in the elderly inhabitants of Helsinki. Background: Low salivary flow and high numbers of salivary microorganisms are associated with the presence of caries, but cannot predict the increment in caries in the elderly. Materials and methods: This study group was derived from a population‐based Helsinki Aging Study, which consisted of a random sample of elderly born in 1904, 1909 and 1914. The 71 dentate elderly who underwent clinical oral examinations at baseline (1990–91) and 5 years later (1995–96) were included in the study group. Decayed, Missing or Filled Tooth (DMFT) and Root Caries Index (RCI) indexes were used to study subject’ caries experience. Data on subjects’ education came from questionnaire studies. The subjects were divided into four groups according to their level of education and occupation. Bivariate and multivariate analyses were used to evaluate relationships between subjects’ caries experience and level of education. Results: At baseline the elderly with high level of education had more teeth and more root surfaces at risk than those with low level of education. Number of teeth decreased (?1.085, p < 0.0001), while both DMFT (1.164, p < 0.0001) and RCI (0.081, p < 0.0001) indices increased during follow‐up. The increments in DMFT and RCI were not directly associated with the level of education. Multivariate analysis in which subjects’ gender, number of teeth, level of education, frequency of eating and frequency of brushing were taken into consideration, showed no significant association with caries increment. Conclusions: Within the limitations of this study it can be concluded that the level of education of the elderly is not directly associated with the increment in caries.  相似文献   
186.
Objectives: To study oral sugar (glucose) clearance and to examine some factors which were believed to either influence or be dependent upon oral glucose clearance. Design: Cross-sectional, clinical study with analysis of records. Setting: Göteborg gerontological and geriatric population studies, Göteborg University, Sweden. Subjects: 71 community-dwelling individuals, 27 men and 44 women, of a representative sample of 260 92-year-old persons. Intervention and Main outcome measures : Glucose concentration was measured in saliva after chewing of a glucose tablet and the clearance was assessed by three different variables: (i) the initial salivary glucose concentration, (ii) the area under the curve (AUC) and (iii) the clearance time. Results: The glucose clearance showed a wide inter-individual variation, which could be explained partly by differences in oral state, chewing time, stimulated salivary secretion rate and medication use. A positive correlation was found between the clearance variables and the number of lactobacilli and mutans streptococci in saliva and the percentage of untreated root caries lesions of the total number of exposed root surfaces. Conclusions : A slow oral sugar clearance is more common among 92-year-olds than younger adults earlier reported in other studies, particularly in those who have uncompensated functional impairments and a high medication history. A decreased oral glucose clearance was associated with high counts of salivary lactobacilli and mutans streptococci and a high proportion of untreated root caries lesions.  相似文献   
187.
A total of 434 White and 148 Black persons from the southern Brazilian city of Porto Alegre were studied in relation to the Pr, Db, Pa, Ps and amylase electrophoretic salivary systems. Concomitantly, individual migration, parent-offspring and marital distances were recorded for these individuals, their spouses and ancestors. As far as these dispersion measures are concerned, White/Black and intergeneration differences were generally higher in the present study than in earlier ones, although the averages found this time were consistently lower than those observed before. The correlations between these measures indicated a higher degree of independence between generations than was previously inferred. In the genetic studies, 21 comparisons between the Porto Alegre distributions and those found in North American, European and African surveys yelded 7 significant differences. In general the allele frequencies in Porto Alegre show intermediate values between those found elsewhere among Blacks and Whites, suggesting admixture in these two racial segments of that city. Using previous estimates of such admixture the gene frequencies of the putative Porto Alegre parental populations were estimated and compared with present European and African results. Relatively large differences were observed for the Db+ andAmy 1 E markers only. No significant associations were detected between the salivary phenotypes and the prevalences of caried, extracted and filled teeth.  相似文献   
188.
Abstract We have constructed a panel of mutants of S. mutans V403 which are defective in one or more of the glucosyltransferase genes ( gtfB,C or D ) or the fructosyltransferase gene ( ftf ). These strains have been tested for virulence in a gnotobiotic rat caries model with reference to both buccal (smooth surface) and sulcal (pit and fissure) carious lesions. Our data suggest differing roles for degradable and non-degradable polymers at buccal and sulcal sites. Non-degradable polymers (made by products of the gtfB and C genes) contributed significantly to the severity of smooth surface lesions. However, our studies suggested their role in pit and fissure lesions was not as important as the role of degradable polymers. Specifically, a mutant deficient in the major insoluble glucan synthesizing activity (product of the gtfB gene) was 25% more cariogenic on sulcal surfaces than was the wild-type V403 strain. We propose that extracellular glucosyltransferases and fructosyltransferase compete for sucrose and that this competition influences pathogenicity at differing tooth sites.  相似文献   
189.
Data from population-based longitudinal studies required to assess the incidence of root caries and associated risk factors are sparse in the literature. To this end, a group of 130 middle-aged and older adults were examined for root caries at baseline and at a follow-up visit between nine and 24 months (median: 16 months). Dental examinations were conducted by one examiner at a Tufts dental clinic using NIDR defined diagnostic criteria. Fifty percent of subjects in this study population developed one or more new root caries lesions over the follow-up period. Also, an annualised increment of 0.60 (SD: 0.72) decayed and filled surfaces per person was observed for the 45–59 year old group while the 70+ group showed an annualised increment of 1.38 (SD: 1.97) DFS in this study. Multivariate logistic regression analysis identified past root caries experience, high plaque score, and high number of teeth (>= 22) to be positively associated with new root caries (p < 0.05).  相似文献   
190.
BackgroundLead (Pb) and Cadmium (Cd) are important environmental contaminants. There is no biological monitoring of exposure to these heavy metals and their potential effect on dental caries in children in Tehran, Iran, a polluted megacity. Therefore, the present study investigated the potential association between Pb and Cd levels in primary teeth and saliva and dental caries.MethodsIn a cross-sectional design, 211 children aged 6–11 years referred to Tehran University of Medical Sciences, School of Dentistry and residing in Tehran were examined. Pb and Cd levels of exfoliated primary teeth and stimulated saliva were determined by atomic absorption spectrophotometry (AAS). Dental caries prevalence was evaluated according to WHO criteria. Socioeconomic status, oral hygiene behavior, snacking frequency and salivary pH data were acquired as confounding factors. Frequency and percentages were reported for categorical variables, mean and standard deviation (SD) for continuous variables, and geometric mean for skewed continuous variables. A simple linear regression and Pearson correlation tests were used for statistical analyses. P-values < 0.05 were considered as significant.ResultThe mean (95 % confidence interval) Pb and Cd levels in teeth were 213.26 ppb (164.29–274.84) and 23.75 ppb (20.86–27.05), respectively. The mean Pb and Cd levels in saliva were 11.83 ppb (10.71–13.06) and 3.18 ppb (2.69–3.75), respectively. Furthermore, Pb and Cd in primary teeth and saliva were not associated (p > 0.05) with socioeconomic status, oral hygiene behavior and snacking frequencyConclusionThis study showed no association between Pb and Cd concentrations in primary teeth and in saliva with dental caries prevalence.  相似文献   
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