摘要:

Abstract –A sport drink mixture (pH 3.2) containing 6% sucrose was given to Osborne‐Mendel rats for 42 days. In some experimental groups the drink was supplemented with 15 ppm F, 38.5 ppm Mg or both F and Mg. The rats were fed a slightly cariogenic powdered diet containing 15% sucrose. Sport drink mixture increased significantly the accumulation of plaque but, compared with a group that drank distilled water, did not affect caries. Addition of fluoride to the sport drink mixture, alone or with magnesium, significantly reduced caries and tended to decrease plaque; addition of magnesium had no clear effect on plaque or caries. In spite of the fact that the rats had a sport drink mixture as the only drink for 6 wk, there were no untoward effects on growth, in histological studies of the inner organs, or in Ca, Mg, Na and K contents of kidney, heart and ao

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01790.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –Eight effervescent preparations and one chewable vitamin C preparation were tested with regard to dental erosion by immersing bovine tooth specimens for 100 h in 100 ml of the test solutions. For comparison, two effervescent calcium preparations were studied. All the vitamin C products caused distinct erosion and disclosure of dentin in the specimens which could not be found in calcium preparations. Calcium release from the bovine teeth varied from 1.08 to 12.99 μg Ca/rnm2/h. Softening of the dental tissue assessed as the Vickers hardness units, was most prominent among the specimens where most calcium release was observed. A crossover clinical trial using a test pannel assigned to 1‐week periods of excellent vs no mechanical cleaning, and with a consumption of 6.6 times more vitamin C tablets than the recommended daily use, revealed no particular impact of the preparation on a variety of oral health parameters. Except for a slight stimulation of the subjects' salivary flow rate 30 min after consuming the vitamin C, all other differences observed could be explained by the accumulation of plaque during the period without mechanical cleaning. Thus, in patients with normal salivary flow rate a short‐term consumption of vitamin C preparations, even in excess, may be regarded as harmless from the dental point of view. However, all the studied preparations are potentially erosive if left in direct contact with the

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01791.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –A significant correlation was found between the results of a dip‐slide test and a conventional agar‐plate method for determination of the salivary Streptococcus mutans population. The growth density of S, mutans around bacitracin discs on the dip‐slide was estimated and examination of the dip‐slides with or without a microscope showed good agreement. The percentage of identical scores between two observers increased from 69 to 84% with the use of a microscope. Scores from dip‐slides inoculated with saliva by means of a cotton swab showed good agreement with those obtained with stimulated saliva. The dip‐slide method is simple and reliable and can be a valuable too in general practice for the estimation of the S. mut

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01792.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –The effect of fluoride ingestion on plasma and urinary cyclic AMP levels was studied in healthy volunteers, children undergoing prophylactic fluoride treatment and in rats. In the first series of experiments fluoride ingestion led to a 20‐fold increase in plasma fluoride concentration, which was unrelated to changes in plasma cyclic AMP. The only significant effect on plasma cyclic AMP occurred prior to fluoride, an effect attributed to stress. In the second series performed in children increases in urinary F‐of up to 200‐fold were associated with slight but nonsignificant changes in cyclic AMP excretion. In rat experiments the blood sampling procedure was associated with a rise in plasma cyclic AMP. When this was prevented by pretreatment with propranolol (3 mg/kg), the effect of fluoride (50 ppm in the drinking water) was tested. A fall in urine production was not associated with any change in cyclic AMP excretion or in nephrogenic cyclic AMP. It is concluded that if fluoride alters cyclic AMP in rats and man the effect is small and easily masked by other factors such as catecholamine release following

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01793.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –Lipopolysaccharides (LPSs) were extracted by phenol‐water From three oral strains of Selenomonas. The preparations were tested for the ability to induce a blastogenic response in cultures of spleen cells from normal and nude BALB/c mice, to activate guinea pig complement and the clotting enzyme system of Limulus polyphemus amoebocytes, and to kill Actinomycin‐D treated mice. The capacity of the three LPSs was comparable to that of enterobacteria

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01794.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –The present study was carried out to examine the effect of application of a fluoride varnish (Duraphat) on experimentally produced caries in vivo. After a 4‐wk period of cariogenic challenge on homologous pairs of premolars, Duraphat was applied on one of the teeth while the other was extracted and saved as a control. The Daraphat treated teeth remained in a cariogenic environment for a new period of 2 wk prior to extraction. All the control teeth displayed the classical characteristics of active incipient subsurface carious lesions. The Duraphat treated lesions showed an increase in surface porosity relative to their controls while the subsurface porosity was dramatically reduced. When examined in the SEM, the corresponding surface appeared smooth with a leveling out of the original surface irregularities. High power microscopy disclosed, however, a distinct network of intercrystalline spaces. Application of Duraphat prior to reestablishment of cariogenic challenge apparently gives rise to a marked redistribution of minerals in active initial carious lesi

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01795.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –The absorbed doses in the body of a Rando‐Alderson phantom were measured in rotational panoramic radiography (OP‐5) with LiF‐700 crystals using conventional intensifying screens and standard collimator, as well as rare earth intensifying screens and a collimator slit of reduced width. The reduction of the absorbed doses obtained by using the latter combination was calculated. The reduction range in different regions was 0–50%. The greatest reduction was obtained in the cranial part of the phantom. In the caudal part little or no reduction was observed, probably because leakage radiation contributes substantially to the absorbed doses in this area. The average dose equivalent was calculated for organs in which measurements were made in several locations. The reduction was about 50% for these organs except for the gonads (8%). Compared to the estimated average annual dose equivalent originating from the natural background radiation sources, the dose equivalent resulting from this X‐ray examination was very small except in the thyroid gland. In this organ the dose equivalent from one exposure corresponded to 36 days of natural background radiation, but it could be reduced to 18 days by using rare earth intensifying screens in combination with reduced

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01796.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –By electron microscopy colloid bodies have been shown to be derived from epithelial cells. It has been suggested, however, that connective tissue cells or components from the basement membrane zone contributed to the formation of colloid bodies. In order to examine these possibilities we stained oral lesions of discoid lupus erythematosus (DLE) with antibodies against intermediate filaments (keratin, vimentin), basement membrane components (laminin, collagen type IV) and fibronectin. IgM was used as a marker for colloid bodies. Colloid bodies were stained positive for keratin, whereas vimentin was never found in colloid bodies. Laminin and collagen type IV were occasionally seen in their periphery probably owing to adherence of basement membrane fragments during apoptosis. Fibronectin was frequently seen at the entire periphery of colloid bodies which may facilitate their elimination by macrophages. In conclusion, connective tissue cells or basement membrane components do not seem to contribute to the formation of colloid bodies in oral DL

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01797.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –Professional commercial divers working with electrical cutting and welding sometimes experience a metallic taste phenomenon. An enquéte study among divers showed no influence of different equipment on the occurrence of such metallic taste, but it seems to occur less frequently in low salinity water, It has been suggested that this metallic taste phenomenon is due to increased corrosion rate of dental restorations, especially of amalgam. Experimental results recording the potential of amalgam specimens placed in the oral cavity of divers during welding, showed influence on the potential, and thus probably on the corrosion rate, during welding only when the diver came into direct contact with the water, e.g. through leakage in the su

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01798.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Abstract –The corrosion of powdered conventional and high Cu dental amalgam was studied in vitro under fixed conditions (100% oxygen, pH 4, and constant weak mechanical action). Results were retrieved from X‐ray diffraction of samples of amalgam and solid corrosion products Formed, in combination with recording of the HC1 consumed to maintain the fixed pH. In the conventional amalgam no corrosion of γ1occurred until all γ2had corroded, whereas in the high Cu amalgam corrosion of γ1occurred from the beginning, concurrent with corrosion of ε and ń. Corrosion products found were AgCl, Hg2Cl2, CuCl2‐3Cu(OH)2, and SnO2. The results may be interpreted as follows: in the conventional amalgam the matrix phase γ1is anodically protected against corrosion as long as any γ2remians; in the high Gu amalgam the least noble phases ε and ń do not protect γ1i

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1986.tb01799.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY