摘要:

The serum concentrations of IgG, IgA and IgM, and the parotid saliva concentration and secretion rate of IgA were examined in 130 subjects, and related to dental caries experience. Subjects were subdivided into an active caries (AC) group and a no-detectable caries (NDC) group. Positive correlations were found between the index of decayed, missing and filled teeth (DMF) and both serum IgA and IgG but not IgM. A significant positive correlation was also found in the NDC group between the concentration of IgA in parotid saliva and the DMF index, but no relationship was seen in the AC group. In the series as a whole, low caries experience was associated with larger volumes of parotid saliva secreted per minute, and a greater secretion rate of salivary IgA than was present in subjects of high caries experience. The results suggest that serum IgG and IgA levels reflect past caries experience, but that salivary IgA may contribute to defence against dental caries.

ISSN:0008-6568    

DOI:10.1159/000260199

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

54 pre-school children who had no caries on the proximal surfaces between their primary molars, were examined every 6 months during V-11/2 year. Plaque samples were collected from the areas mentioned above. Samples from the right side were used for cultures and samples from the left side for gram-stained smears. From the cultures, the following ratios were determined: (1) number of aerobic/anaerobic microorganisms, (2) number of Streptococcus mutans/number of microaerophilic streptococci, (3) number of microorganisms producing intracellular polysac-charide/total number of microorganisms, and (4) number of streptococcitotal number of microorganisms. In the gram-stained smears the distribution of different gram-positive and gram-negative microorganisms were studied. The only parameter which changed in connection with caries development was the ratio aerobic/anaerobic microorganisms. The ratio ranging from 7.5 to 139.5% prior to the period of caries development decreased to between 0.5 and 43.5% in connection with caries development. With regard to the other ratios between viable counts, no correlation could be established with the development of caries. Similarly, no changes in the composition of the microflora were observed in the gram-stained smears.

ISSN:0008-6568    

DOI:10.1159/000260200

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

The remineralizing property of SnF2 was studied by treating artificial white spot enamel lesions for 0.5, 6 and 24 h and 1 week in a 4% SnF2 solution at 50 °C. Remineralization as opposed to recalcification was observed in all treated samples and was studied using microradiography and microprobe analysis. It appeared that remineralization started in the outer part of the intact surface layer covering the sub-surface lesion. With increasing time, the centre of the sub-surface lesion became remineralized. In a fully remineralized lesion it was no longer possible to distinguish between the surface layer and the sub-surface lesion. Some sections appeared to be fully remineralized after only 6 h treatment with SnF2. Microprobe analysis showed that the variation in density was highly correlated with the Sn concentration. Some possible mechanisms and reactions that may be involved in this remineralization are discussed

ISSN:0008-6568    

DOI:10.1159/000260201

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

The accuracy and reproducability of hardness measurements have been investigated in this study. Sound and demineralized enamel were used as the main test materials. The reproducability of hardness measurements on artificial white spot lesions produced by a hydroxyethyl cellulose/lactic acid demineralizing solution was also investigated on embedded cross-sections. The operator error was found to be less than 5% when reading both steel and enamel indentations. The maximum hardness of the surface layer and the minimum hardness of the subsurface lesion were measured in three positions in each of 10 artificial white spot lesions. An analysis of the results showed that: (a) the hardness values at the same distance from the surface but in different areas of the same lesion were very similar; (b) hardness values between lesions were also very even; (c) the drop in hardness after demineralization was related to the initial hardness of the enamel.

ISSN:0008-6568    

DOI:10.1159/000260202

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

The effect of differing periods of 4% stannous fluoride treatment at 50 °C on artificial white spot lesions was investigated on cross-sections. Microhardness, densitometric and microprobe measurements were made through the same place on the sections. Both hardness and radiodensity increased significantly after half an hour and reached a maximum after 6h treatment with SnF2 solution. The rate of hardness increase, even in heavily demineralized sections, appears to be superior to that so far achieved using remineralizing solutions. The microprobe results indicated that the increase in radiodensity was linked to the tin uptake. There was, however, no such correlation with the hardness increase, which appears to be due to an alteration in structure

ISSN:0008-6568    

DOI:10.1159/000260203

出版商:S. Karger AG    

年代:1976

数据来源: Karger

摘要:

The effects of pre-eruptive and post-eruptive exposure to fluoride (F) administered in milk and in water were studied separately using Osborne-Mendel rats fed diet 2000 and infected by Streptococcus mutans 6715. In assessing pre-eruptive effects, two groups of animals received either milk or water containing F at a dose of 1 mg/kg bodyweight by stomach tube from 5 to 15 days of age. Although these animals showed a significant increase in enamel uptake of F, their caries scores did not differ from those of untreated controls. In a second experiment, where post-eruptive effects were assessed, animals which drank 3 ml of milk or water containing 50 ppm F 5 days per week for 8 weeks also showed a significant increase in enamel F. The increase was slightly greater when the F was provided in milk than when it was in water. The post-eruptive administration of F resulted in significantly reduced levels of buccallingual caries but without effect on proximal or sulcal surfaces. There were no differences between the use of milk or water as the vehicle with respect to caries scores.

ISSN:0008-6568    

DOI:10.1159/000260204

出版商:S. Karger AG    

年代:1976

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260205

出版商:S. Karger AG    

年代:1976

数据来源: Karger