Volatile Sulfur Compounds In Mouth Air Research Articles

Interdental and subgingival microbiota may affect the tongue microbial ecology and oral malodour in health, gingivitis and periodontitis.

Oral malodour is often observed in gingivitis and chronic periodontitis patients, and the tongue microbiota is thought to play a major role in malodorous gas production, including volatile sulphur compounds (VSCs) such as hydrogen sulphide (H2 S) and methanethiol (CH3 SH). This study aimed to examine the link between the presence of VSCs in mouth air (as a marker of oral malodour) and the oral bacterial ecology in the tongue and periodontal niches of healthy, gingivitis and periodontitis patients. Participants were clinically assessed using plaque index, bleeding on probing (BOP) and periodontal probing depths, and VSC concentrations in their oral cavity measured using a portable gas chromatograph. Tongue scrapings, subgingival and interdental plaque were collected from healthy individuals (n=22), and those with gingivitis (n=14) or chronic periodontitis (n=15). The bacterial 16S rRNA gene region V3-V4 in these samples was sequenced, and the sequences were analysed using the minimum entropy decomposition pipeline. Elevated VSC concentrations and CH3 SH:H2 S were observed in periodontitis compared with health. Significant ecological differences were observed in the tongue microbiota of healthy subjects with high plaque scores compared to low plaque scores, suggesting a possible connection between the microbiota of the tongue and the periodontium and that key dysbiotic changes may be initiated in the clinically healthy individuals who have higher dental plaque accumulation. Greater subgingival bacterial diversity was positively associated with H2 S in mouth air. Periodontopathic bacteria known to be prolific VSC producers increased in abundance on the tongue associated with increased bleeding on probing (BOP) and total percentage of periodontal pockets >6mm, supporting the suggestion that the tongue may become a reservoir for periodontopathogens. This study highlights the importance of the periodontal microbiota in malodour and has detected dysbiotic changes in the tongue microbiota in periodontitis.

Inactivating effects of the lactoperoxidase system on bacterial lyases involved in oral malodour production.

The main components of oral malodour have been identified as volatile sulfur compounds (VSCs), including hydrogen sulfide (H(2)S) and methyl mercaptan (CH(3)SH). The lactoperoxidase (LPO) system (consisting of LPO, glucose oxidase, glucose and thiocyanate) was previously shown to exhibit antimicrobial activities against some oral bacteria in vitro and suppressive effects on VSCs in mouth air in a clinical trial. Here, we examined the in vitro effects of the LPO system on the activities of the bacterial lyases involved in the production of VSCs by oral anaerobes. The exposure of crude bacterial extracts of Fusobacterium nucleatum and Porphyromonas gingivalis or purified methionine γ-lyase to the LPO system resulted in the inactivation of their lyase activities through l-cysteine and l-methionine, which was linked to the production of H(2)S and CH(3)SH, respectively. The exposure of living F. nucleatum and P. gingivalis cells to the LPO system resulted in the suppression of cell numbers and lyase activities. The inactivation of the crude bacterial extracts of F. nucleatum and purified methionine γ-lyase by the LPO system was partly recovered by the addition of DTT. Therefore, the LPO system may inactivate bacterial lyases including methionine γ-lyase by reacting with the free cysteine residues of lyases. These results suggested that the LPO system suppresses the production of VSCs not only through its antimicrobial effects, but also by its inactivating effects on the bacterial lyases of F. nucleatum and P. gingivalis.

Effect of non-surgical periodontal therapy on the concentration of volatile sulfur compound in mouth air of a group of Nigerian young adults

Background:The major goal of non-surgical periodontal therapy is to reduce or eliminate the subgingival pathogenic microbial flora that is known to be associated with volatile sulfur compounds (VSC).Aim:The aim of this study was, therefore, to determine the effect of non-surgical periodontal therapy on the concentration of VSC in mouth air of young adults.Subjects and Methods:Four hundred subjects, grouped into two based on the absence or presence of periodontal diseases, were involved in this study. Basic periodontal examination was used for the grouping. The measurement of the concentration of the VSC in the mouth air of the subjects was done objectively, using the Halimeter, before and after the therapy, and at recall visits 2 weeks and 6 weeks after therapy. Chi-square and Paired t-test were used to find statistical significance.Results:The results revealed that at baseline, 78.7% (48/61) of the subjects who had VSC concentration more than 250 parts per billion (ppb) were from the group with periodontal disease. Immediately after non-surgical periodontal therapy, only 8.5% (17/200) of the subjects with periodontal disease had VSC concentration of more than 250 ppb while all the subjects with no periodontal disease had VSC concentration less than 181 ppb. The same pattern of reduction in the concentration of the VSC and improvement in oral hygiene was also obtained 2 weeks and 6 weeks after therapy.Conclusion:It can be concluded that non-surgical periodontal therapy brought about reduction in the concentration of volatile sulfur compounds in mouth air of young adults.

Association Between Volatile Sulfur Compounds and Periodontal Disease Progression in Elderly Non‐Smokers

Periodontal pathogenic microorganisms produce volatile sulfur compounds (VSCs), such as hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. VSCs are toxic to periodontal tissue. Therefore, there is a relationship between periodontitis and the VSC level of mouth air. However, the association between VSC and periodontal disease progression has not been investigated in a longitudinal study. The purpose of this study is to evaluate the association between VSCs in mouth air and periodontal disease progression among elderly dentulous non-smokers. Two hundred forty-one dentulous non-smokers (103 males and 138 females; all 70 years old) had their VSC levels examined with a portable sulfide monitor, and their periodontal status was assessed. Periodontal examinations were performed at baseline and once a year for 3 years to investigate the clinical attachment levels of all teeth. Participants were classified by membership in tertile groups (lowest, middle, and highest) according to the value of baseline VSC measurements. In negative binomial regression analysis, the number of teeth with periodontal disease progression for participants in the highest tertile of VSC measurement was greater (incidence rate ratio of 1.33, P = 0.011) than for the reference group (lowest tertile of VSC measurement) after simultaneously adjusting for sex, number of remaining teeth, and maximum clinical attachment level. VSC measurements were significantly associated with periodontal disease progression in a non-smoking dentulous elderly population. This suggests that VSC measurements are useful for the diagnosis of periodontal disease progression.

Tablets containing a cysteine protease, actinidine, reduce oral malodor: a crossover study

Tongue coating (TC) mainly consists of protein mostly from exfoliated epithelial cells. Until now, to reduce TC accumulation, only mechanical measures have been available, and the procedure involves unpleasant side effects, such as gagging reflex or carcinogenesis related to mechanical stimulation. We expected that protease might be effective in reducing the accumulation of TC causing oral malodor. The purpose of this study was to determine the effect of long-term use of candy tablets containing protease, actinidine, on both TC accumulation and concentration of volatile sulfur compounds (VSCs) in mouth air. We employed 14 subjects aged 24 to 54 years old for this study, and conducted a double-blind randomized crossover trial. The subjects sucked the tablets containing actinidine three times a day until the sixth day after starting the study. The tablets without actinidine were utilized as a placebo. Measurements of VSC concentration and TC accumulation were carried out before and after chewing tablets on the first day, and also on the seventh day. The levels of VSC and TC significantly (p < 0.05) decreased after tablets were taken on the first day in both the test and placebo groups. There was a statistically significant decrease (p < 0.05) in VSC after seven days of use only in the test group. The results of the study suggest that the tablets containing actinidine had an accumulative effect in reducing VSC in mouth air with long-term use.

Fluorescein mercuric acetate—A novel sensor for oral malodour detection

Volatile sulphur compounds (VSC) like hydrogen sulphide, methyl mercaptan and dimethyl sulphide are the primary constituents of oral malodour. We have developed a fluorimetric assay, using fluorescein mercuric(II) acetate (FMA), for the quantification of VSC in mouth air. The assay is based on the quenching of fluorescence of FMA on reaction with VSC. The detection limit of the sensor is 0.06μgL−1 for VSC. The analyte concentration, the pH of solution and the time for reaction have been optimized to achieve rapid and sensitive response for VSC levels in the range of 0–0.75μgL−1.The response of the sensor has been validated with a commercial halimeter. The sensor was also used to study the VSC levels in human subjects with healthy oral hygiene. The level of VSC in mouth air of healthy subjects ranged between 0.2 and 0.4μgL−1. The assay can be a potential diagnostic tool to evaluate any change in the VSC levels in mouth air due to different environmental factors. The sensor is cost effective, sensitive and simple to use. It can be used for routine clinical evaluation of oral malodour and also as a self-test kit.

Diurnal changes in oral malodour among dental-office workers

Dentistry is a major resource for the treatment of halitosis, therefore dental professionals must also pay attention to their own oral malodour for professional courtesy. However, oral malodour among dental professionals has not yet been investigated. In this study, the diurnal changes in oral malodour in dental-office workers were determined, and preventative measures were assessed. Diurnal changes in the levels of volatile sulphur compounds (VSCs), which are the main cause of oral malodour, in mouth air were determined with a gas chromatograph specially designed for such analysis and the effects of several preventive measures were evaluated. High concentrations of VSCs in mouth air persisted during the morning and decreased after lunch. Tongue-cleaning followed by tooth brushing decreased VSCs dramatically. Further measures such as eating breakfast, drinking tea or using zinc mouthwash significantly decreased VSCs, but the effects were limited in dental hygienists who suffered from persistent oral malodour, especially in the afternoon. Eating breakfast, cleaning the tongue followed by brushing the teeth and zinc chloride mouthwash were very effective in preventing oral malodour in dental-office workers; however, the effectiveness of these preventive measures was limited in dental hygienists.

Relationship between volatile sulfur compounds in mouth air and systemic disease

This study examined the relationship between volatile sulfur compounds (VSCs), including hydrogen sulphide (H2S), methyl mercaptan (CH3SH) and dimethyl sulphide [(CH3)2S], in mouth air of patients and a history of systemic disease. The subjects were 387 residents (174 males and 213 females) of Fukuoka Prefecture, Japan, who participated in an oral and systemic health survey for elderly persons (mean age: 61.8, s.d. 2.8 years). The VSCs were measured using a portable gas chromatograph (OralChroma). The H2S concentrations were significantly greater in the 132 subjects with a history of hypertension and the 41 subjects with a history of respiratory disease, including pneumonia, pulmonary emphysema and bronchitis, than in those without such a history. The CH3SH concentrations were significantly greater in those with a history of hypertension. The 16 subjects with a history of cerebrovascular disease, including intracerebral haemorrhage, cerebral infarction, and subarachnoid haemorrhage, and the 58 subjects with a history of liver disease, including hepatitis, alcoholic liver disease, drug-induced liver injury, fatty liver and liver cirrhosis, showed significantly greater (CH3)2S concentrations (p < 0.05). These results suggest an association between the production of VSCs in mouth air and systemic diseases such as hypertension as well as respiratory, cerebrovascular and liver diseases.

Volatile sulphide compound levels in mouth air with plaque-related periodontal disease are associated with a change in the proportion of periodontopathic bacteria in saliva

This study investigated whether oral malodour with plaque-related periodontal disease was associated with the prevalence of periodontopathic bacteria in saliva and tongue debris. The subjects were 30 patients who visited the Breath Odour Clinic. An oral examination was performed at baseline and two months after periodontal treatment, and included measuring the volatile sulphur compounds (VSCs) in mouth air. The proportions of five periodontopathic bacteria versus all bacteria in saliva and tongue debris were determined using real-time polymerase chain reaction. The subjects were classified into four groups based on the existence of VSCs above the organoleptic threshold level (TVSC) and a periodontal pocket ⩾4 mm (PD4). At baseline, the group with TVSC/PD4 had higher proportions of periodontopathic bacteria in saliva compared to those with TVSC/no PD4 and no TVSC/no PD4, but there were no differences in the proportions in tongue debris among the four groups. At follow-up, the proportion of periodontopathic bacteria in the saliva of the group with TVSC/PD4 was significantly reduced, as compared to that at baseline, and the VSCs and periodontal health improved. The results suggested that the reduction in VSCs in mouth air of subjects with periodontal disease might be associated with the prevalence of periodontopathic bacteria in saliva.

Effect of Green Tea on Volatile Sulfur Compounds in Mouth Air

Many food products are claimed to be effective in controlling halitosis. Halitosis is caused mainly by volatile sulfur compounds (VSCs) such as H(2)S and CH(3)SH produced in the oral cavity. Oral microorganisms degrade proteinaceous substrates to cysteine and methionine, which are then converted to VSCs. Most treatments for halitosis focus on controlling the number of microorganisms in the oral cavity. Since tea polyphenols have been shown to have antimicrobial and deodorant effects, we have investigated whether green tea powder reduces VSCs in mouth air, and compared its effectiveness with that of other foods which are claimed to control halitosis. Immediately after administering the products, green tea showed the largest reduction in concentration of both H(2)S and CH(3)SH gases, especially CH(3)SH which also demonstrated a better correlation with odor strength than H(2)S; however, no reduction was observed at 1, 2 and 3 h after administration. Chewing gum, mints and parsley-seed oil product did not reduce the concentration of VSCs in mouth air at any time. Toothpaste, mints and green tea strongly inhibited VSCs production in a saliva-putrefaction system, but chewing gum and parsley-seed oil product could not inhibit saliva putrefaction. Toothpaste and green tea also demonstrated strong deodorant activities in vitro, but no significant deodorant activity of mints, chewing gum or parsley-seed oil product were observed. We concluded that green tea was very effective in reducing oral malodor temporarily because of its disinfectant and deodorant activities, whereas other foods were not effective.

Development of a Compact and Simple Gas Chromatography for Oral Malodor Measurement

Volatile sulfur compounds (VSCs) in oral air are the only type of gases correlated with the strength of oral malodor. We developed a compact and simple gas chromatograph (GC) equipped with a newly invented indium oxide semiconductor gas sensor (SCS) for measuring the concentrations of VSCs in mouth air. We have assessed the correlation between measurements with a GC-SCS and those with a regular GC. Oral air samples from randomly selected volunteers were analyzed with both a GC-SCS and a GC with a flame photometric detector (FPD), which is specific to VSCs, and GC-SCS measurements were compared to those obtained by GC-FPD. Subsequently, oral air samples before and after mouthrinsing with 5% ethanol mouthwash were analyzed to determine the effect of ethanol on VSC measurements by GC-SCS. There were strong correlations between VSC concentrations determined using these two gas chromatography methods (hydrogen sulfide, R=0.821, P<0.0001; methyl mercaptan, R=0.870, P<0.0001; and dimethyl sulfide, R=0.770, P<0.0001). Although GC-SCS can differentiate ethanol and VSCs in oral air samples after mouthrinsing, GC-SCS measurements demonstrated higher values than those obtained by GC-FPD; however, this discrepancy improved over time due to the reduced effect of ethanol. The results suggest that GC-SCS may be useful for the diagnosis of halitosis.

A sorbent tube for oral malodour monitoring

Volatile sulphur compounds (VSCs) and particularly hydrogen sulphide are considered as the predominant gases causing oral malodour. In this paper, a simple alarm sensor has been developed for VSCs determination in mouth air. The device consists of a glass tube packed with a solid sensing phase. The VSCs react with the sensing phase to produce a change in the colour of the sensor visible with a naked eye. Different “reagents” were investigated to develop the sensing phase (neocuproine + Cu(II), bathocuproine + Cu(II), resazurin, 2,6-dichlorophenolindophenol and lead acetate), finding the neocuproine + Cu(II) as the best for our purposes. Also, different substrates such as Amberlite XAD-4 and XAD-7 and different trademarks of silica gel were tested as solid supports, being selected the silica gel. A device consisting of a glass tube packed with the sensing phase was optimized and tested with halitosis patients as a rapid illness test and the results compared with those obtained with a commercially available instrument, the Halimeter™, used for the determination of VSCs in mouth air. The results exhibited acceptable agreement between the proposed “qualitative” alarm sensor and a commercially available technique selected as reference, showing the possibility of using this “visual sensor” to control the halitosis and its evolution with an eventual treatment, by the own patient.

Low salivary flow and volatile sulfur compounds in mouth air.

The purpose of this study was to determine whether a reduction of salivary flow would influence the production of methylmercaptan (CH(3)SH) and hydrogen sulfide (H(2)S), which are volatile sulfur compounds (VSCs) known to cause oral malodor. The VSCs in mouth air were measured by means of gas chromatography. Spitting and masticatory (stimulated) methods were used to determine the salivary flow rates of 174 patients. There was no significant correlation between the level of VSCs and salivary flow rate. However, subjects with extremely low resting salivary flow rates had significantly higher CH(3)SH and H(2)S concentrations and tongue-coating scores than those with higher resting salivary flow rates. Moreover, logistic analyses revealed that extremely low resting salivary flow, the increase in tongue coating, and a probing pocket depth greater than 4 mm were strong explanatory factors for the generation of VSCs, which could have caused oral malodor. These findings suggested that an extreme reduction in resting saliva influenced the generation of CH(3)SH and H(2)S in mouth air.

Portable oral malodor analyzer using highly sensitive In 2O 3 gas sensor combined with a simple gas chromatography system

A portable oral malodor analyzer was developed for quantitative detection of volatile sulfur compounds (VSCs) in mouth air using a combination of a semiconductor gas sensor and a compact gas chromatography system. We found that In 2O 3 doped with Au is the optimum sensing material of the gas sensor for obtaining a high sensitivity to measure all the VSCs in mouth air with low concentration ranges. A specific column design, simple sampling system and signal processing method were applied for achieving a portable analyzer without using a standard pressurized carrier gas. This analyzer can easily measure the concentration of essential components of oral malodor individually and quantitatively over a wide range from 50 to 1000 ppb (v/v).

Variation in oral volatile sulphur compound formation

It has been suggested that the level of orally produced volatile sulphur compounds (VSCs) can be of use when monitoring oral malodour or in determining patients at risk of periodontal disease in longitudinal studies. It is not known, however, to what extent the level of VSC in mouth air is a stable, individual characteristic over time. Aim: The hypothesis to be tested was that the level of VSC in mouth air is an individual trait that is stable over time. Methods: Two groups of dental students participated in the study (n = 30 and n = 11). The amount of available substrate for VSC formation was standardized by rinses with 6 mM aqueous solutions of cysteine (pH 7.2). Part 1 used a Halimeter® to measure 'morning breath' and response to cysteine rinses. Part 2 measured response to cysteine rinsing using a gas chromatograph. Repeated measurements provided information concerning the longitudinal intra-individual variations in level of oral VSC formation. Results: Both groups showed large intra-individual variations in oral VSC. The differences were enhanced by cysteine rinses. Conclusion: The hypothesis was not supported. Oral VSC levels cannot be taken as diagnostic criteria in a normal population because of marked intra-individual variations over time.