PubMed Health⌕ Search

Biomedical subjects

O J Bouwsma

Publications and source records attributed to O J Bouwsma.

13 recordsLinked to original sources
PubMed1997

A comparison of intraoral antimicrobial effects of stabilized stannous fluoride dentifrice, baking soda/peroxide dentifrice, conventional NaF dentifrice and essential oil mouthrinse.

The intraoral antimicrobial activity of four commercial oral products-conventional NaF dentifrice (Crest), baking soda/peroxide/NaF dentifrice (Mentadent), essential oil mouthrinse (Listerine) and SnF2 dentifrice (Crest Plus Gum Care)-have been compared in three test regimens. Formulations were compared for their ability to suppress the regrowth and apical extension of dental plaque following toothbrushing during thirty hours of non-brushing where products were used as oral rinses (30-hour plaque regrowth model). Formulations were also compared for their ability to suppress the colony-forming units (cfu) of facultative anaerobic bacteria sampled from buccal gingival surfaces following use (Gingival Surface Microbial Index-GSMI model). Lastly, formulations were compared for effects in suppressing the glycolytic metabolic activity and regrowth activity of in vivo-treated dental plaques sampled at various periods following topical use and incubated under controlled ex vivo conditions (Plaque Glycolysis and Regrowth-PGRM model). In thirty-hour plaque regrowth testing, the rank ordered antimicrobial efficacy of formulations followed SnF2 > essential oils > NaF = water = baking soda/peroxide. In GSMI testing, all formulations were shown to suppress the cfu of facultative anaerobic bacteria relative to baseline, although SnF2 treatment was observed to reduce bacterial levels to a significantly greater degree than NaF dentifrice or baking soda/peroxide dentifrice up to two hours following brushing. In PGRM testing, the SnF2 dentifrice provided significant inhibition of bacterial metabolism and regrowth following topical application when compared with the NaF dentifrice as control. The baking soda/peroxide dentifrice provided no reduction in either bacterial metabolism or regrowth in PGRM. Previous studies had demonstrated modest effects for essential oil rinse in reducing PGRM plaque regrowth, with no effects for this treatment on plaque metabolism. Overall, these results demonstrate that SnF2 dentifrice provides substantial intraoral antimicrobial effects. The essential oil mouthrinse also exhibits significant intraoral antimicrobial effects, albeit apparently less than SnF2 dentifrice. The baking soda/peroxide dentifrice did not produce any antimicrobial effects following in vivo use compared with conventional dentifrice. These results provide mechanistic rationale for the chemotherapeutic efficacy of SnF2 and essential oil formulations in reducing gingivitis, while providing no support for the expectation of clinical efficacy for formulations containing baking soda and peroxide.

Adult↗
PubMed1996

Gingival fluid tetracycline release from bioerodible gels.

Intracrevicular antimicrobial therapy is consistent with the site-specific nature of periodontitis. Considerable research has focused on the use of nonresorbable fibers. However, a bioerodible system is desirable. The purpose of this study was to assess tetracycline release and safety following a single application of a syringable 35% tetracycline hydrochloride in a lactic-glycolic acid gel. 31 generally healthy adult volunteers (mean age = 59 years) were enrolled in and completed this randomized, double-blind eight day study. 2, 6-10 mm non-adjacent interproximal pockets that bled on pocket probing were chosen as experimental sites in each subject. I experimental site and the surrounding gingival crevice received small particle size tetracycline in gel while the other site received larger particle size tetracycline in gel. Gingival crevicular fluid (GCF) was collected prior to treatment and 15 min, 1, 2, 3, 4 and 8 days post-treatment. GCF tetracyline concentrations were determined by agar diffusion bioassay and GCF volume measurements. 61% and 71% of sites had > or = 100 micrograms/ml tetracycline 3 days following application of large (mean concentration = 430 +/- 92 micrograms/ml) and small particle gels (mean concentration = 418 +/- 70 micrograms/ml), respectively. 37% and 55% of sites had measurable tetracycline 8 days after placement of large (mean concentration = 86 +/- 31 micrograms/ml) and small particle gels (mean concentration = 293 +/- 79 micrograms/ml), respectively. The most common adverse event was "bitter taste" (10% of subjects). Based upon the reduction in probing depths and % of sites bleeding on probing at 8 days relative to pretreatment, and the absence of any serious adverse events, it is concluded that these bioerodible gels are safe, and since the bacteriostatic range for most putative periodontopathogens is in the 2-10 micrograms/ml range, the tetracycline levels observed at days 3 and 8 likely represent significant antimicrobial efficacy.

Adult↗
PubMed1996

The status, future, and problems of oral antiseptics.

Caries and periodontal disease, the most widespread oral diseases, are commonly treated with various oral antiseptics. These antiseptics are derived from different chemical categories and have different mechanisms of action. Even though the properties of an ideal oral antiseptic have been identified, its formulation has proven elusive. Recent studies with chlorhexidine, triclosan, an amine and stannous fluoride rinse, and essential oil rinse, and others are discussed. Development of novel antiseptic products continues. The hope for the future is that now antiseptic products will treat oral disease better and oral health will improve.

Anti-Infective Agents, Local↗
PubMed1992

Comparison of a chlorhexidine rinse and a wooden interdental cleaner in reducing interdental gingivitis.

The purpose of this study was to evaluate the effectiveness of an antimicrobial rinse (chlorhexidine) compared to a positive control of mechanical oral hygiene in reducing interdental gingival inflammation. The mechanical group showed a significantly greater reduction in interdental gingivitis as determined by bleeding compared to the chemical rinse. Even though the chemical rinse has been shown to be effective in reducing inflammation on the visible buccal and lingual gingival surfaces, it is significantly less effective than the mechanical device in reducing bleeding in the interdental area.

Adult↗
PubMed1989

Rerandomization tests for analyzing correlated data from dental studies.

Dental research studies often produce relatively small data sets in which observations are serially or spatially correlated. Rerandomization tests are presented as alternatives to analysis of variance and multivariate analysis for assessing group differences using such data. Rerandomization tests are particularly useful when the investigator is unwilling to make strong assumptions about the nature of the serial correlation or the distribution of the data. Two examples are discussed that demonstrate these techniques.

Data Interpretation, Statistical↗
PubMed1989

The prevalence of interdental gingival inflammation: a report from the 1986 ADA annual health screening.

This study screened 1986 ADA annual session participants for interdental gingival inflammation by using the Eastman Interdental Bleeding Index (EIBI). The EIBI provides a sensitive and objective measure of interdental gingival inflammation, and has been shown to be reliable. At least one bleeding site was found in 81% of the 435 dentists examined. This study showed that in a dental population, the prevalence of gingival inflammation was high when the health of interdental tissues was assessed.

American Dental Association↗
PubMed1980

Constituents of Cannabis sativa L. XVIII--Electron voltage selected ion monitoring study of cannabinoids.

Cannabis sativa L. contains more than 420 different constituents. Sixty-one of these constituents are cannabinoids. The electron voltage selected ion monitoring technique was used in the study of this unique group on natural compounds. Mass spectra of each compound were recorded at various eV settings (5.5-21 eV). The electron voltage selected ion recordings were obtained by plotting the relative intensities of characteristic fragment ions against electron voltage. The method was proven useful in the structure analysis of cannabinoids since it requires only minute quantities of sample. It was possible to recognize homologs and to differentiate positional and double bond isomers as well as cannabinoids with the same molecular weight.

Cannabinoids↗
PubMed1979

Interaction of the antimalarial alpha-dibutylaminomethyl-2,6-bis(trifluoromethylphenyl)-4-pyridinemethanol with human serum albumin.

Binding of the antimalarial alpha-dibutylaminomethyl-2,6-bis(trifluoromethylphenyl)-4-pyridinemethanol with human serum albumin was studied using difference spectroscopy, fluorescence quenching, and equilibrium dialysis. Results indicated that the number of high affinity binding sites of the drug on protein is 0.45, with the total number of binding sites being 3.3--4.0. The binding constants were in the range of 0.57--4.00 x 10(6) M-1. The drug was bound more strongly to a nonionic detergent than to either a cationic or anionic detergent. Interpretation of these data and fluorescence quenching results indicated that the drug is possibly bound to a hydrophobic site on human serum albumin.

Antimalarials↗
PubMed1978

Characterization of pharmacologically important prototropic species derived from a pyridinemethanol antimalarial by electronic absorption and fluorescence spectroscopy.

Variations of the absorption and fluorescence spectra of the experimental antimalarial drug, alpha-dibutylaminomethyl-2,6-bis(p-trifluoromethylphenyl)-4-pyridinemethanol, were investigated throughout the pH region in concentrated sulfuric acid media and in n-hexane. The predominant prototropic species at physiological pH is the singly charged cation. In the pH 6--12 region, the structured fluorescence of the monocation is quenched with the concomitant appearance of a diffuse, long wavelength emission while the corresponding absorption spectra shift only slightly to longer wavelengths. Furthermore, the dibutylamino group exhibits an unusually low basicity. This behavior is explained as due to the formation of an intramolecular hydrogen bond in the neutral molecule in the ground and lowest excited singlet states. A similar intramolecular hydrogen bond in the monocation is not spectroscopically visible.

Antimalarials↗
PubMed1978

Methylthio metabolites of naphthalen excreted by the rat.

Eight methylthio metabolites have been found as urinary products of the metabolism of naphthalene in the rat. One was 1-methylthionaphthalene. A second was a methylthio analog and the dihydrodiol, and a third was naphthalene substituted with one hydroxyl and one methylthio group. Two compounds with common structural elements were found; one of these was prepared by synthesis from anti-1,2:3,4-naphthalene dioxide and one from 1 beta, 2 alpha-dithyroxy-3 alpha, 4 alpha-epoxy-1,2,3,4-tetrahydronaphthalene by reaction with 2-keto-4-methylthiobutyric acid or with methionine. Each of these compounds contained one methythio group and three hydroxyl groups substituted on a tetrahydronaphthalene structure. Two metabolites with two methylthio groups and two hydroxyl substituents on a tetrahydronaphthalene ring were also detected; one of these was prepared by synthesis from the dioxide. The most likely metabolic origin of these methylthio metabolites is through the reaction of epoxides (including the diepoxide) with a nucleophile which may be methyl mercaptan, 2-keto-4-methylthiobutyric acid, or methionine.

Animals↗
PubMed1978

Formation in vivo of deuterated methylthio metabolites of naphthalene from L-methionine (methyl-d--3).

Studies were carried out with deuterated methionine (methyl-d--3) to determine if methylthio metabolites of naphthalene were formed in vivo by reaction with methionine-derived metabolites. Rats were maintained on a methionine-free diet for nine days followed by eight days on the same diet supplemented with L-methionine-d--3 prior to administration of naphthalene. When naphthalene metabolites isolated from urine were characterized by GC and GC-MS procedures, it was found that the incorporation of deuterium into the methylthio metabolites, as well as into a catechol methyl ether, was approximately 40%. These results show that the methyl group was derived from methionine.

Animals↗