摘要:

The levels of selected cariogenic and obligately anaerobic bacteria have been compared in carious dentine taken from fissures, smooth surfaces, and root surfaces. The numbers of infected dentinal tubules were determined by immunohistological staining using species-specific antisera against selected bacteria. Selective localization was observed; mutans streptococci were the predominant bacteria in dentine from fissures and smooth surface coronal caries, but not from root surface caries. The proportion of mutans streptococci was higher in the shallow and middle layers of dentine from fissures and smooth surface coronal carious lesions than from the deep layers. In root surface caries, Actinomyces spp. were the predominant bacteria, and were present at higher levels in the deep layer of root lesions than in the shallow and middle layers. The proportion of Lactobacillus spp. was relatively low despite its high detection frequency in all layers of the three types of carious lesion. Immunohistological staining with species-specific antisera was able to reveal the distribution and the localization of various bacteria in carious dentine.

ISSN:0008-6568    

DOI:10.1159/000261635

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The inhibitory effect of oolong tea extract (OTE) containing polymerized polyphenols on plaque deposition was examined in 35 human volunteers. Thirty-five human volunteers, aged 18-29 years, who received extensive oral prophylactic procedures were requested to refrain from all oral hygiene procedures for 4 days, and to rinse their mouth with 0.5 mg/ml OTE solution in 0.2% ethanol before and after every intake of food and before sleeping at night. No restriction regarding meals was given during the test period, except to refrain from teas or coffee. Plaque deposition was evaluated after disclosing the teeth with Erythrocin at the termination of this experiment. The study was repeated 1 week after the first trial, but only 0.2% ethanol without OTE was used for mouthrinsing in the second trial. OTE was found to significantly inhibit plaque deposition in volunteers, although mouthrinsing with OTE solution had no significant effect on the number of mutans streptococci in unstimulated whole saliva.

ISSN:0008-6568    

DOI:10.1159/000261636

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The distribution of sucrose in whole saliva and in saliva from seven different regions of the mouth was determined in 10 subjects over the 10-min period following the chewing of a doughnut, sucking on a mint candy, the drinking of orange juice, or use of a 10% sucrose mouthrinse. With all products, the sucrose was distributed non-uniformly, with particularly low concentrations on the lingual surfaces of the lower incisors and the facial surfaces of the upper molars. Clearance was also most rapid from these sites. Since the depth and duration of a Stephan curve in dental plaque is influenced by the sugar concentration to which the plaque is exposed, the results, together with previous results on salivary film velocity in different regions of the mouth, help to provide an explanation for the site-specificity of smooth-surface caries and of supragingival calculus deposition.

ISSN:0008-6568    

DOI:10.1159/000261637

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The relative contribution of the host genetic effect on the susceptibility to dental caries was examined. Four inbred strains of male rats (BN/Sea, F344/Ms, PVG/ cSea, and WKA/Sea) were inoculated with Streptococcus mutans and fed a cariogenic diet. The caries scores of the molar teeth were compared among these four strains, and the degree of genetic determination was estimated by analysis of variance. Statistically significant differences in caries scores were found among these strains (F344 > WKA > PVG/c > BN), and a high degree of genetic determination was obtained.

ISSN:0008-6568    

DOI:10.1159/000261638

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The aims of this study were to evaluate the level of mutans streptococci in two groups of Thai (Bangkok) children; to relate the findings to caries prevalence and to the caries increment over 2 years, and to study whether different sealant and fluoride programmes affected levels of mutans streptococci over a 2-year period. The baseline survey comprised 1,114 children aged 12 years. For the sealant project, a minimum of three caries-free permanent molars was required; 752 children aged 12-13 and 512 children aged 7-8 years were distributed into five groups: control group, Delton fissure sealant group, glass ionomer fissure sealant applied by dentist (GlC-dentist group) or by school teachers given a 3-day course (GlC-teacher group), and an HF group (0.5% HF solution applied 3 times). The WHO standard criteria were used to record caries. Prevalence of mutans streptococci was estimated using the Strip mutans® test. Mean DMFT (n = 1,114) of 12-years-olds was 2.96; 17% had Strip mutans class 0 (low level), 32% class 1, 33% class 2 and 18% class 3 (the corresponding mean DFT ± SD for each mutans streptococci class was 1.84 ± 2.33, 2.23+2.14, 3.18+2.75, and 3.59+3.01 respectively). For the 7- to 8-year-olds (n = 512), mean df teeth at baseline was 5.36 (d = 5.19; f = 0.17); 5% had Strip mutans class 0, 17% class 1, 33% class 2 and 45% class 3 (the corresponding mean df teeth was 3.19+2.5, 4.13+2.84, 4.89 ± 2.94 and 6.39+3.16 respectively). Mean DFS occlusal caries increments for age group 12-13 years were: control 0.70 surfaces, Delton 0.05, GlC-dentist 0.48, GlC-teacher 0.56, and HF 0.76 DFS. For age group 7-8 years, mean DFS occlusal caries increment was: control 0.66 surfaces, GlC-dentist 0.32, GIC-teacher 0.17 and HF 0.44. In conclusion, levels of mutans streptococci were significantly related to caries prevalence and increment. The study also showed that the outcome of various treatments was associated with the levels of mutans streptococci at baseline.

ISSN:0008-6568    

DOI:10.1159/000261639

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

The quality of radiographic diagnosis of occlusal carries was examined with special attention to the diagnosis of lesions in dentin. Eighty-four extracted teeth, most of them with occlusal caries of different severity and some apparently sound, were radiographed. For validation purposes, the lesion depths were recorded during a drilling procedure. Ten dentists interpreted the radiographs. On average, 12% of the sound surfaces were wrongly diagnosed radiographically as having caries (false positives), 33% of the enamel lesions were identified on radiographs, and 62% of the small dentin lesions and 100% of the big dentin lesions were diagnosed radiographically (true positives). There was wide variation in the ability to identify dentin caries correctly between the observers; the sensitivity values ranged from 0.77 to 1.0 (mean 0.90) and the specificity values from 0.45 to 0.93 (mean 0.76). The dentist demonstrating the highest diagnostic quality (measured by the area beneath the receiver operating characteristics curve) had only about 9% false positives (1-specifícity), while the dentist who had the lowest diagnostic quality scored caries in about 55% of the teeth in the control group. Both of them had 96% true positives. The tendency to make false-positive registrations in the dentin adjacent to enamel seems to be a major problem in radio-graphic diagnosis of occlusal caries. The radiograph has significant value in the diagnosis of occlusal dentin caries, but the great variations between observers indicate the need for training and calibration.

ISSN:0008-6568    

DOI:10.1159/000261640

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

Since a first survey in 1969, juvenile caries prevalence in the second largest city of the Netherlands has attained a European minimum of DMFT = 0.8 in 11.9-year-old children. However, the curves of improvement have been flattening out since the mid-eighthies. Incidental variations between 1984 and 1993, especially of caries prevalence in the deciduous teeth of 5- and 7-year-old children, do not indicate a turn to the secular downward trend. The stability of juvenile oral health does not seem to be due to changes in dietary habits, nor to public health measures, but is mainly due to good oral health and use of fluoride dentifrices by the children.

ISSN:0008-6568    

DOI:10.1159/000261641

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000261642

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000317510

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000317511

出版商:S. Karger AG    

年代:1994

数据来源: Karger