Monofluorophosphate Blocks Internal Polysaccharide Synthesis in Streptococcus mutans.

Streptococcus mutans is the leading cause of dental caries worldwide by accumulating a glycogen-like internal polysaccharide (IPS) that contributes to cariogenicity when sugars are in excess. Sodium monofluorophosphate (MFP) is an active anticariogenic compound in toothpastes. Herein, we show that MFP inhibits (with an I0.

Remineralization potential of an anticaries/antigingivitis mouthrinse.

Purpose: To assess the ability of a new formulation (Listerine with 0.022% NaF) to remineralize initially decalcified bovine enamel compared to a positive control, clinically established 0.022% NaF rinse.

Ab initio study of AmCl(+): f-f spectroscopy and chemical binding.

A valence full configuration interaction study with a polarized double-zeta quality basis set has been carried out for the lowest 49 electronic states of AmCl(+). The calculations use a pseudopotential treatment for the core electrons and incorporate a one-electron spin-orbit interaction operator. Electrons in the valence s, p, d, and f subshells were included in the active space.

Effect of fluoride/essential oils-containing mouthrinse on the microhardness of demineralized bovine enamel.

Purpose: To assess the ability of a fluoride mouthrinse containing a fixed combination of essential oils (thymol, menthol, eucalyptol, and methyl salicylate) to inhibit demineralization as compared with that of a clinically established NaF rinse.

Methods: Inhibition in sound bovine enamel to demineralization was assessed utilizing a cyclic T/R/D (treatment/remineralization/demineralization) in vitro model where Knoop microhardness was monitored over 6, 12, and 18 T/R/D cycles.

Results: Both fluoride-containing mouthrinses resulted in statistically significant increase in microhardness when compared to the non-fluoride control mouthrinse, possibly demonstrating and validating the in vitro model's ability to parallel the clinically established benefit of a 0.

The inhibition of mercury absorption by dietary ethanol in humans: cross-sectional and case-control studies.

Background: Since the inhibition of mercury absorption by ethanol was serendipitously discovered in 1965,(1) a limited number of small number studies with both animal and human subjects have reported results consistent with this finding.

Aims: To investigate this phenomenon in a large scale human study with low level Hg exposed dentists.

Methods: Data were collected for a sample of 1171 dentists, and both cross sectional and case-control methods were utilised to examine the data.

Behavioral effects of low-level exposure to Hg0 among dental professionals: a cross-study evaluation of psychomotor effects.

A Across-study design was used to evaluate the sensitivities of five psychomotor tasks previously used to assess preclinical effects of low-level Hg0 (urinary < or =55 microg/l). Pooling dental professional subject populations from six studies conducted over the last 6 years, a larger study population was obtained with a high degree of uniformity (N = 230). The five psychomotor tests were: Intentional Hand Steadiness Test (IHST); Finger Tapping: The One-Hole Test: NES Simple Reaction Time (SRT); and Hand Tremor.

Short-chain carboxylic acid concentration in human gingival crevicular fluid.

Short-chain carboxylic acids (e.g., lactic acid, propionic acid, butyric acid) are metabolic by-products of bacterial metabolism which can accumulate in the gingival crevice.

The relationship of gingival crevicular fluid short chain carboxylic acid concentration to gingival inflammation.

Short-chain carboxylic acids (SCCA; C < or = 5; e.g., lactic acid, propionic acid, butyric acid) are metabolic by-products of bacterial metabolism which accumulate in the gingival crevice, and exhibit significant biological activity, including the ability to alter gene expression.

The validity of spot urine samples for low-level occupational mercury exposure assessment and relationship to porphyrin and creatinine excretion rates.

Hg and porphyrin levels in single void urine specimens (spot samples) were compared with calculated 24-hr urine levels in 35 (20 [correction of 25] male and 15 female) practicing dentists who had been occupationally exposed to low levels of elemental Hg. The study aimed to: 1) determine the individual variability for Hg and porphyrin concentrations in spot samples over a 24-hr period; 2) test for the presence of diurnal variation in urinary Hg and porphyrin concentrations; and 3) determine the time of day at which a spot sample would give a Hg concentration closest to the 24-hr average concentration. Results confirmed previous reports of a first-order diurnal pattern with a mid-morning peak for Hg concentration (P < .

Factors contributing to mercury exposure in dentists.

Although mercury exposure levels among dentists have been steadily decreasing, occupational mercury exposure among dental professionals continues to be a matter of interest. This study examined personal professional and office characteristics of dentists to determine which factors contribute most to exposure. The resulting information will help dental professionals change their practices to minimize unnecessary exposure to elemental mercury.

Subgingival temperature as a gingival inflammatory indicator.

Elevated temperature is one of 4 cardinal inflammatory signs. Previous work indicates that subgingival temperature assessments are accurate and re- liable, and provide objective, quantitative information over a broad 10 degrees C range, in small 0.1 degrees C increments with a direct, immediate report on the inflammatory status at the pocket base.

Behavioral effects of low-level exposure to elemental Hg among dentists.

Exposure thresholds for health effects associated with elemental mercury (Hg degree) exposure were examined by comparing behavioral test scores of 19 exposed (mean urinary Hg = 36 micrograms/l) with those of 20 unexposed dentists. Thirty-six micrograms Hg/l is 7 times greater than the 5 micrograms Hg/l mean level measured in a national sample of dentists. To improve the distinction between recent and cumulative effects, the study also evaluated porphyrin concentrations in urine, which are correlated with renal Hg content (a measure of cumulative body burden).

Comparative attributes for the description of the relative efficacy of therapeutic agents: general concepts and definitions, and application to the American Dental Association guidelines for the comparison of the clinical anticaries efficacy of fluoride dentifrices.

Comparative attributes are terms or phrases commonly employed in the vernacular of the biomedical literature to convey the results of comparative studies. Examples are such terms as "equivalent" or "superior." Recently, there has developed an increasing tendency in certain areas of application toward the institution of guidelines which provide both a uniform set of criteria for defining such attributes and a set of requirements which must be satisfied in order to demonstrate that such attributes may hold in a particular situation.

Fractional mercury levels in Brazilian gold refiners and miners.

A field study survey of individuals residing in the region of Para, Brazil, was conducted to determine fractional mercury levels in individuals at risk for exposure in the Brazilian Amazon region. Subjects with a history of exposure to mercury either in the gold mining or refining industry, or exposure to these processes through proximity were included. Three groups were identified as either having recent (less than 2 d since last exposure), intermediate (less than 60 d), or remote (greater than 60 d) exposure to mercury vapors.

Urinary porphyrin profiles as a biomarker of mercury exposure: studies on dentists with occupational exposure to mercury vapor.

Porphyrins are formed as intermediates in the biosynthesis of heme. In humans and other mammals, porphyrins with eight, seven, six, five, and four carboxyl groups are excreted in the urine in a well-established pattern. Mercury selectively alters porphyrin metabolism in kidney proximal tubule cells, leading to an altered urinary porphyrin excretion pattern.

Use of an in vitro model to assess the effects of APF gel treatment on the staining potential of dental porcelain.

Porcelains and resin composites exposed to acidulated phosphate fluorides (APF) have been reported to result in increased roughness, loss of weight, and loss of specular reflectance (gloss). Six samples of five commercial porcelains were subjected to five four-minute treatments with APF gels. Samples were then subjected to a nine-day cyclic staining procedure that utilized a tea, coffee, and mucin mixture.

On-site screening for urinary Hg concentrations and correlation with glomerular and renal tubular function.

At the American Dental Association 1985 and 1986 Annual Sessions, an on-site screening for mercury was conducted as part of the Health Screening Program (HSP) to identify dentists having elevated urinary mercury concentrations. The data generated from this study were used to examine the relationship between elevated urinary mercury exposure and kidney dysfunction. Kidney dysfunction was assessed by measurement of serum and urine beta 2 microglobulin concentrations, serum creatinine, and creatinine clearance.

Assessment of the effectiveness of glove use as a barrier technique in the dental operatory.

To assess the effectiveness of routine glove use as a barrier technique in the dental operatory, the relationship between frequency of glove use and hepatitis B infection was examined. Hepatitis B screening results and information on infection control practices of 1,109 dentists who attended the 1985 annual session were compiled and statistically analyzed. The results showed that 18% of the dentists wore gloves routinely, 65% wore gloves intermittently, and 17% never wore gloves.

Behaviors of dentists in regard to dental and medical appointments. ADA Health Foundation Research Institute.

During the Health Screening Program at the ADA's annual session, 1,160 dentists completed questionnaires about their personal medical and dental visits within the past year. Findings from this study were compared with findings from other surveys of these behaviors in the general population. Results indicated that dentists visited dentists more often than did members of the general population.