ISSN:0008-6568    

DOI:10.1159/000259726

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000259727

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000259728

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000259729

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The morphology of human dental plaque has been studied with the electron microscope. In the inner part of the plaque, especially in the region adjacent to the tooth surface, many microorganisms exhibit unusually thick cell walls and contain large amounts of intracellular polysaccharide. The magnitude of both phenomena diminishes towards the saliva-plaque interface. Both cell wall thickening and intracellular polysaccharide storage are considered to be manifestations of a so called ‘unbalanced growth’ situation, suggesting a low or negligible rate of cell multiplicat

ISSN:0008-6568    

DOI:10.1159/000259730

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Recently developed micro-sampling and micro-analytical techniques have been used to determine the distribution of calcium, phosphorus and protein in individual enamel sections. Absolute values for calcium, phosphorus and protein were variable (30–40% calcium, 13–23% phosphorus and 0.002–0.015 mol amino acids/100 µg enamel), but consistent patterns of distribution were revealed in the tissue. The average values for calcium (37.5%), phosphorus (17.5%) and Ca:P ratio (2.1) agreed with those quoted in the literature. The volume of tissue occupied by the mineral and the significance of the composition patterns with respect to enamel formation and caries are dis

ISSN:0008-6568    

DOI:10.1159/000259731

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

On clinically sound buccal and lingual surfaces of 130 extracted teeth, class V cavities were prepared and filled. In some cases previously filled teeth were used. In vitro caries around the fillings was produced by immersing the teeth in an acid-gelatin system, the pH of which was held within the values 4.0–5.2 by means of lactic acid. Duration of the experiments varied within the range of 5–200 days. A number of teeth which were filled, but not exposed to the acid gelatin, were used as controls. Ground sections in series were prepared through the teeth with the fillings in situ and studied by ordinary transmitted and incident light, polarized light, ultraviolet light, and microradiography. The lesions produced consisted of two regions, the outer lesion and the cavity wall lesion. In the enamel the shape of the former and its relation to the latter seemed to be influenced by the angle made by the cavity wall with the prisms. The outer lesion developed by an action on the outer surface of the enamel or cementum and showed the features of a primary attack. Usually the wall lesion was a narrow subsurface defect in the enamel or the enamel and the dentine of the cavity wall. It represented an initial stage of the caries process and gradually encompassed the whole filling without penetrating deeply into the tissue. The development of the wall lesion was determined by the amalgam-dental tissue interface into which hydrogen ions must have diffused from the acidified gelatin. The demineralization seemed to have acted perpendicularly to the surface of the cavity wall in which reprecipitation had taken place in a few ca

ISSN:0008-6568    

DOI:10.1159/000259733

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Infant feeding with water-diluted cow’s milk or, still more, dry-milk formulas supplies many times greater fluoride doses than breast-feeding, already with low water fluoride content. An investigation of 260 schoolchildren in Uppsala (1.2 ppm F in the drinking water) showed only an insignificant trend towards increased enamel mottling in typically formula-fed children, compared to breast-fed children. Among 25 children in the small community Billesholm (5.5 ppm F in the drinking water) the same trend was only slightly stronger. No difference in caries rate was found between breast-fed and bottle-fed children in any of these communities. No health hazard seems to be involved in any of these fluoride doses, but the need to consider all the factors that can be changed when introducing new nutritional and therapeutic methods is pointed ou

ISSN:0008-6568    

DOI:10.1159/000259734

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Urinary fluoride excretion under different conditions was examined using a fluoride ion activity electrode. The mean 24-hour urinary fluoride excretion in adult women was 0.89 mg in Basel with water-fluoridation at the 1 ppm level. In two women using a domestic salt with 250 mg F/kg the mean fluoride excretion was 1.04 mg and in three persons working in a children’s home using the same salt it was 1.19 mg. This result seems to indicate, that a packeted salt with 250 mg F/kg should produce about the same caries-protective effect as water-fluoridation. With salt-fluoridation the urinary fluoride concentration reaches its maximum 2–4 hours after a meal. In the urine of newborn boys the mean fluoride concentration was 0.08 ppm compared with 0.58 ppm in the post partum urine of their mothers, confirming the placental F-barr

ISSN:0008-6568    

DOI:10.1159/000259735

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000259736

出版商:S. Karger AG    

年代:1971

数据来源: Karger