摘要:

The plasma fluoride concentration in 15 subjects living in three different districts with 9.6, 1.2 and 0.25 ppm fluoride in the drinking water, was followed over 36 h. In the 9.6-ppm-fluoride area there was a wide fluctuation in the plasma fluoride concentration during the day compared to the 1.2- and 0.25-ppm-fluoride areas. A correlation coefficient of 0.71 was found between renal clearance of F and urinary flow. The results of this study illustrate the necessity for frequent or standardized blood sampling in studies on plasma fluoride concentrations in man.

ISSN:0008-6568    

DOI:10.1159/000260321

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

A method for the determination of acid production in suspensions of 5–10 mg (wet weight) of human dental plaque is described. With this method it was possible to investigate the fermentability of up to 10–15 substances with plaque material from one subject. The amount of alkali required per unit of time to keep pH constant was followed by an automatic recording titration system. Sorbitol, maltitol and Lycasin® were fermented at a significantly slower rate than glucose, sucrose and invert sugar. No acid production was found from mannitol and xylitol. The acid production activity with fructose was on average 21% lower than that from glucose. However, this difference was not statistically well established (p < 0.05) in experiments with 5 subj

ISSN:0008-6568    

DOI:10.1159/000260322

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Enamel fluoride levels of rats subjected to a 7-day precaries test period during which they received 0, 10, 50, 100 or 150 ppm F in their drinking water and then maintained for 56 days on a high starch diet and either non-F drinking water or 10 ppm F drinking water were compared to F levels in intact enamel of animals similarly treated but maintained for 56 days on a high sucrose caries test diet, infected with a caries-active flora and given 10 ppm F water. Enamel of animals exposed to a caries test challenge acquired much larger amounts of F from water containing 10 ppm F than those with the same F exposure but no caries test challenge. The results are interpreted as being due to fluoride enhanced remineralization of early carious demineralization.

ISSN:0008-6568    

DOI:10.1159/000260323

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

The symbiosis of two Streptococcus mutans strains differing in carbohydrate metabolism, and a strain of Veillonella alcalescens was studied in dental plaque in gnotobiotic rats. The lactate dehydrogenase in S. mutans FIL but not in C 67-1, is independent on fructose 1,6-diphosphate. S. mutans FIL was found to produce significantly more lactic acid in plaque than C 67-1. Both strains produced acetic acid and ethanol in addition to lactic acid. The proportion of Veillonella was higher in combination with FIL than with C 67-1 (15% and 0.05, respectively). Accordingly, lactic acid was found to be significantly reduced in plaque with FIL plus Veillonella. Further, the amount of biomass was reduced in fissures containing FIL plus Veillonella. The combination of these two effects could explain the significant caries reduction observed in the rats harbouring FIL plus Veillonella. Only trace amounts of propionic acid were detected in the plaque inhabiting Veillonella.

ISSN:0008-6568    

DOI:10.1159/000260324

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Saline, as well as detergent-soluble, phosphomonoesterase activity was quantitatively assayed from freeze-dried dentine in sound and carious human teeth. The activity was measured from 10-mg samples of dentine taken from 3 to 6 different areas of one tooth (76 teeth). The rate of hydrolysis of p-nitrophenylphosphate (p-NPP) was measured and calculated per milligram protein or per milligram of the dry weight of the sample both at acidic (possible reflecting acid phosphatase activity EC 3.1.3.2) and alkaline (alkaline phosphatase EC 3.1.3.1) pH values. At the acidic level, Triton X-100 treatment revealed higher activity than did saline treatment in sound dentine. In dentine from carious teeth p-NPP was hydrolyzed most rapidly by the enzymes solubilized in saline solution. The highest activity was observed in NaCl solution solubilized soft carious dentine from gangrenous teeth. At alkaline pH values Triton X-100 revealed higher activity, both in sound and carious dentine, when compared to saline treatment. The most rapid rate of hydrolysis was observed in the peripulpal dentine layer under incipient carious changes in dentine. The increase of this activity was also reflected in the peripulpal area of the apex. These observations support the hypothesis that the dentine as a tissue reacts already in the early stages of caries both anabolically and catabolically.

ISSN:0008-6568    

DOI:10.1159/000260325

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Using specific antisera to the proline-rich proteins A and C, a quantitative assay has been developed for human acidic proline-rich proteins. By adding varying amounts of hydroxyapatite to a given volume of saliva, the adsorption of acidic proline-rich proteins and total protein to hydroxyapatite has been determined for stimulated and unstimulated parotid and submandibular saliva. The maximum amount of acidic proline-rich proteins adsorbed (ADSmax) varied from 85 to 97% of the total acidic proline-rich proteins present in unadsorbed saliva. ADSmax for total protein varied from 41 to 79%. The amount of hydroxyapatite needed for half maximal adsorption (HA50) was consistently smaller for acidic proline-rich proteins than for total protein and for the secretions from any gland, HA50 was consistently smaller for unstimulated than stimulated saliva. HA50 values from one individual were consistently smaller than the corresponding HA50 values from a second individual. The mean concentration of acidic proline-rich proteins in unadsorbed saliva was 50 ± 26 mg/l00 ml and the mean contribution of acidic proline-rich proteins to hydroxyapatite-adsorbed proteins was 42% ± SD 23 of total adsorbed proteins. On the basis of equilibrium dialysis experiments with purified protein A and C in buffers with pH and ionic strength similar to salivary secretions, it was estimated that the concentration of calcium bound to acidic proline-rich proteins varied from 8 μM in unstimulated submandibular saliva to 41 μM in stimulated submandibular saliva. The concentration of calcium bound to acidic proline-rich proteins therefore apparently depends on the type of salivary secret

ISSN:0008-6568    

DOI:10.1159/000260326

出版商:S. Karger AG    

年代:1978

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260327

出版商:S. Karger AG    

年代:1978

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260328

出版商:S. Karger AG    

年代:1978

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260329

出版商:S. Karger AG    

年代:1978

数据来源: Karger

ISSN:0008-6568    

DOI:10.1159/000260330

出版商:S. Karger AG    

年代:1978

数据来源: Karger