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J Tonzetich

Publications and source records attributed to J Tonzetich.

At least 37 records · Page 2Linked to original sources
PubMed1984

Effect of hydrogen sulfide and methyl mercaptan on the permeability of oral mucosa.

Hydrogen sulfide (H2S) and methyl mercaptan (CH3SH) are the volatile sulfur compounds (VSC) that were investigated for a possible role in the etiology of periodontal disease. The results show that the permeability of porcine non-keratinized sublingual mucosa is increased by up to 75% or 103% following exposure to H2S and CH3SH, respectively. The effect may be attributed to VSC reaction with tissue components resulting in alteration in the integrity of the tissue barrier. The increase in permeability of the mucosa to [35S]-Na2SO4 was dependent on both the time of exposure and concentration of VSC in the head-space. The [35S]-H2S was retained by the mucosal tissue and was able to penetrate the intact layers consisting of non-keratinized epithelium, basal membrane, and connective tissue. Treatment of the mucosa with 0.22% ZnCl2, either prior to or after exposure to CH3SH, nullified the effect of CH3SH and restored the permeability to a state similar to that observed in control 95% air/5% CO2 systems.

Animals↗
PubMed1981

Volatiles of exogenous origin from the human oral cavity.

The volatiles found in the headspace above male and female saliva were examined by combined gas chromatography--mass spectrometry. This had led to the identification of a number of constituents of exogenous origin. The most likely source of these products are atmospheric and water pollutants as well as food stuffs and cosmetic products. Volatiles from saliva represent a potential medium for the detection of reproductive states as well as local and systemic diseases. Consequently, knowledge of compounds not arising from the body's metabolic process if important to prevent their identification as anomalous metabolites.

Adult↗
PubMed1981

Characterization of volatile sulphur production by pathogenic and non-pathogenic strains of oral Bacteroides.

Marked differences were observed in intermediate sulphur metabolism between non-pathogenic strains of Bacteroides melaninogenicus var melaninogenicus (CP-) and pathogenic Bacteroides melaninogenicus asaccharolyticus (CP+). The CP+ strains, which produced collagenase and protease and caused formation of abscesses when injected subcutaneously into groins of guinea pigs, produced copious amounts of volatile sulphur compounds (VSC) which consisted predominantly of CH3SH and (CH3S)2. Hydrogen sulphide occurred in considerably lesser amounts. CP+ cultures yielded 8-fold more total volatile S, 15-fold more CH3SH and 260-fold more (CH3S)2 during 24 h of incubation in trypticase-yeast extract medium. Whereas H2S accounted for 60 per cent of the total volatile S content of the head-space of CP- cultures, it represented only 8 per cent of the volatile S in CP + systems. Although the CP-organisms did not grow as well as CP +, the differences in concentration of VSC may be only partly related to the disparity in growth rates. When the VSC concentrations were calculated on the basis of equivalent optical density of 1.0, the CP + strains still produced over 3-fold more total volatile S, 6-fold more CH3SH and 100-fold more (CH3S)2. A similar allowance for growth rate suggests that CP-strains may possess a greater potential to produce H2S. Both groups metabolized S-containing amino acids and serine, resulting in appreciable increases in H2S production by CP-. However, the two groups appeared to metabolize the carbon moiety of cystine an cysteine by different pathways. The addition of glucose to the medium depressed total volatile S production by both CP+ and CP-strains, attributable mostly to lower H2S levels. Whereas the omission of yeast extract and charcoal treatment of trypticase did not adversely effect the activity of CP+, it further markedly reduced the capacity of CP-cultures to produce VSC. These results suggest that VSC analysis offers a convenient means of assessing strain differences and pathogenic potential of B. melaninogenicus.

Bacteroides↗
PubMed1981

Quantitative differences in volatiles from healthy mouths and mouths with periodontitis.

It has been suggested that orally derived volatile aromatic amines may be of possible diagnostic use and may contribute to the etiology or pathogenesis of periodontal disease. Using gas chromatography and gas chromatography/mass spectrometry, we identified and quantitated pyridine and picolines in the headspace of incubated whole saliva from healthy and diseased subjects. The oral health of subjects was evaluated by four standard oral-health indices. Volatile aromatic amines were virtually absent from subjects with healthy oral cavities, but were present in the oral cavities of subjects with periodontitis to the extent of 636.4 (SEM 154.7) ng/5 mL of saliva. Pyridine and picolines in saliva of diseased subjects may be related to the disease process.

Humans↗
PubMed1977

Production and origin of oral malodor: a review of mechanisms and methods of analysis.

Organoleptic studies indicate that the oral cavity is usually the principal source of physiologic malodor associated with the early morning halitosis. In all individuals, regardless of the age or health status of the oral tissues, the most intense oral malodor is exhibited after prolonged periods of reduced saliva flow and abstinence from food and liquid. This results from normal metabolic activity in the oral cavity and is accentuated in cases with periodontal involvement. Physiologic oral malodor is transient in duration as it can be controlled to varying degrees in most individuals by oral hygiene measures, such as tooth brushing, dental prophylaxis, tongue scraping and rinsing with antiseptic mouth washes. Experimental evidence strongly suggests that putrefaction of sulphur-containing proteinaceous substrates by predominantly gram-negative oral microorganisms is the primary cause of oral malodor. Optimum putrefactive activity occurs in low carbohydrate environment, physiological pH, and anaerobic conditions. Salivary sediment containing the exfoliated epithelial cells is the primary source of substrate which exists in a disulphide state. Proteolysis and reduction of disulphide bonds precedes the formation of odor. The odor intensity of putrescent saliva and plaque head-space vapor has been correlated with the concentration of volatile sulphur compounds consisting of hydrogen sulphide, methyl mercaptan, dimethyl sulphide and dimethyl disulphide. Except for dimethyl disulphide, the same sulphur-containing compounds have been found in mouth air of all tested individuals. Hydrogen sulphide and methyl mercaptan emanate an offensive putrid odor and account for approxiamtely 90% of the total sulphur content of mouth air. In half of the population tested, methyl mercaptan and hydrogen sulphide content of early morning mouth air is sufficiently high to account for the oral malodor. Brushing studies indicate that both plaque and tongue are important sources of malodor with most of the odor emanating from the dorso-posterior surface of the tongue. None of the gas chromatographic or mass spectrometric analyses have detected the presence of amines, indole, or skatole in the head-space, mouth air, or breath vapor samples.

Amino Acids↗
PubMed1976

Reduction of malodor by oral cleansing procedures.

Organoleptic and gas chromatographic methods were employed to establish the threshold of odor objectionability of methylmercaptan and hydrogen sulfide and to assess the relative effectiveness of different oral hygiene measures to reduce the malodor to acceptable levels. The study showed that methylmercaptan and hydrogen sulfide concentrations below 0.5 ng. and 1.5 ng., respectively, are considered nonobjectionable. Gas chromatographic analyses indicate that these concentrations were exceeded in the early morning mouth air samples of approximately 50 per cent of the adult population studied. In these instances, methylmercaptan and hydrogen sulfide occurred in sufficiently high concentrations to account for the malodor. Brushing studies suggest that the early morning malodor arising from the oral cavity can be controlled by proper oral hygiene. The tongue was the major source of both offending compounds in the persons studied. Methods that involved cleansing of the dorsoposterior surface of the tongue caused the most pronounced reductions of both compounds. Since methylmercaptan was found to be more objectionable and to exhibit a lower threshold of objectionability, it was more difficult to reduce to acceptable levels.

Adult↗