Non-oral etiologies of oral malodor and altered chemosensation

Preliminary investigation of a combined herbal extract of Aruncus dioicus, Cirsium nipponicum, and Ocimum basilicum for halitosis

BACKGROUND

Halitosis, the unpleasant odor in the oral cavity, has garnered increased attention and concern due to the growing significance of social interaction. SGE-107, a blend of 3 botanical drugs-Korean goat's beard, Cirsium tanakae, and Basil-with caffeic acid as its indicator component. This study aims to investigate the efficacy of SGE-107 in treating halitosis in patients with mild gastrointestinal symptoms.

METHODS

We enrolled 25 participants with oral malodor and dyspeptic symptoms. We assessed the severity of halitosis using the visual analog scale. Throughout a 4-week period of administering SGE-107, we evaluated both objective and subjective parameters, including the halitosis-associated life-quality test, the Korean gastrointestinal symptom rating scale, levels of volatile sulfur compounds, salivary flow rate, oral moisture, tongue index, Winkel tongue coating index, and tongue temperature.

RESULTS

After the intervention period, both the visual analog scale (5.88 ± 1.03 vs 2.38 ± 0.93, P < .001) and the scores of the halitosis-associated life-quality test (31.21 ± 11.78 vs 13.83 ± 6.38, P < .001) showed significant reductions. The proportion of participants with abnormal levels of methyl mercaptan (a volatile sulfur compound) also significantly decreased (17, 70.8% vs 9, 37.5%, P = .039). Furthermore, there were significant improvements in reflux, constipation, diarrhea, and the total scores on the Korean gastrointestinal symptom rating scale. Throughout the study period, only 2 participants experienced mild adverse events.

CONCLUSION

SGE-107 appears to be a safe and effective treatment for halitosis-associated with gastrointestinal symptoms; nevertheless, the limited sample size necessitates further large-scale randomized, controlled studies to confirm our findings.

Microbiota and Malodor-Etiology and Management

Accumulating evidence indicates that microbiota plays a critical role in physiological processes in humans. However, it might also contribute to body malodor by producing numerous odorous molecules such as ammonia, volatile sulfur compounds or trimethylamine. Although malodor is commonly overlooked by physicians, it constitutes a major problem for many otherwise healthy people. Thus, this review aims to investigate most common causes of malodor and describe potential therapeutic options. We searched PUBMED and Google Scholar databases to identify the clinical and pre-clinical studies on bad body smell, malodor, halitosis and microbiota. Unpleasant smell might originate from the mouth, skin, urine or reproductive fluids and is usually caused by odorants that are produced by resident bacterial flora. The accumulation of odorous compounds might result from diet, specific composition of microbiota, as well as compromised function of the liver, intestines and kidneys. Evidence-based guidelines for management of body malodor are lacking and no universal treatment exists. However, the alleviation of the symptoms may be achieved by controlling the diet and physical elimination of bacteria and/or accumulated odorants.

Halitosis and the Tonsils

Objective

Halitosis secondary to pathology of the palatine tonsils is considered airway (type 2) halitosis in the etiologic classification. Reports differ as to the proportion of objective halitosis complaints that have tonsillar etiology, with some giving this figure as 3%. Due to their immunologic role, even healthy tonsils usually possess some subclinical inflammation. The tonsil crypt system is also the most ideal environment for anaerobic bacterial activity in the upper respiratory tract. Tonsillar halitosis is thought to occur mainly because of chronic caseous tonsillitis and tonsillolithiasis (tonsil stones). Tonsillectomy and various cryptolysis techniques are reported to improve halitosis in such cases. In this article, diagnostic methods and evidence for interventions are reviewed.

Data Source

Medline search.

Review Methods

Studies reporting the efficacy of any intervention (medical or surgical) on tonsillar halitosis were included, whether halitosis was the focus or one of several measures.

Conclusions

There are insufficient high-quality studies on this topic. Improved methodology, for example, use of control groups and utilization of more accurate halitosis detection/quantification techniques, are required.

Implications for Practice

Lack of evidence currently prevents firm conclusions, but the following is recommended: (1) Use reliable methods for halitosis diagnosis and confirmation of tonsillar etiology. Initial treatment such as tongue scraping is useful to rule out oral halitosis. (2) Tonsillar procedures are contraindicated in: subjective halitosis, non-tonsillar etiology, or if medical management resolves halitosis. (3) Where indicated and where facilities permit, less invasive techniques such as laser cryptolysis may be preferable to tonsillectomy in adults, potentially avoiding general anesthetic and the higher risk associated with tonsillectomy in this group.

Association between viral hepatitis B infection and halitosis

OBJECTIVE

Oral malodor can be increased in breath of liver patients. However, no study has been performed for the association between volatile sulfur compounds (VSCs) and viral hepatitis. The aim of the present study was to determine the relationship between viral hepatitis and VSCs.

METHODS

This study analyzed 182 subjects and measured hydrogen sulfide (H2S), methyl mercaptan (CH3SH) and dimethyl sulfide [(CH3)2S] using the OralChroma(®). Hepatitis type B was evaluated. Periodontal health was assessed using the Community Periodontal Index (CPI) and bleeding on probing (BOP). Tongue coating score (TCS) was evaluated. Multiple logistic regression analyses were conducted to evaluate the relationship.

RESULTS

Viral hepatitis had an elevated odds of dimethyl sulfide defined halitosis (OR = 9.22, 95% CI = 2.08-40.95) after controlling for age, gender, alcohol consumption, current smoking, periodontitis, BOP, TCS and tongue brushing habit. The magnitude of the association between viral hepatitis and VSCs defined halitosis attenuated with adjustment of mediators (alcohol consumption, periodontitis, BOP, TCS and tongue brushing habit for hydrogen sulfide defined halitosis; periodontitis, TCS and tongue brushing habit for methyl mercaptan defined halitosis; tongue brushing habit for dimethyl sulfide defined halitosis).

CONCLUSIONS

Findings of this study suggest that viral hepatitis may be associated with methyl mercaptan defined halitosis.

Cellular scent of influenza virus infection

Volatile organic compounds (VOCs) emanating from humans have the potential to revolutionize non-invasive diagnostics. Yet, little is known about how these compounds are generated by complex biological systems, and even less is known about how these compounds are reflective of a particular physiological state. In this proof-of-concept study, we examined VOCs produced directly at the cellular level from B lymphoblastoid cells upon infection with three live influenza virus subtypes: H9N2 (avian), H6N2 (avian), and H1N1 (human). Using a single cell line helped to alleviate some of the complexity and variability when studying VOC production by an entire organism, and it allowed us to discern marked differences in VOC production upon infection of the cells. The patterns of VOCs produced in response to infection were unique for each virus subtype, while several other non-specific VOCs were produced after infections with all three strains. Also, there was a specific time course of VOC release post infection. Among emitted VOCs, production of esters and other oxygenated compounds was particularly notable, and these may be attributed to increased oxidative stress resulting from infection. Elucidating VOC signatures that result from the host cells response to infection may yield an avenue for non-invasive diagnostics and therapy of influenza and other viral infections.

Halitosis: the multidisciplinary approach

Halitosis, bad breath or oral malodour are all synonyms for the same pathology. Halitosis has a large social and economic impact. For the majority of patients suffering from bad breath, it causes embarrassment and affects their social communication and life. Moreover,halitosis can be indicative of underlying diseases. Only a limited number of scientific publications were presented in this field until 1995. Ever since, a large amount of research is published, often with lack of evidence. In general, intraoral conditions, like insufficient dental hygiene, periodontitis or tongue coating are considered to be the most important cause (85%) for halitosis. Therefore, dentists and periodontologists are the first-line professionals to be confronted with this problem. They should be well aware of the origin, the detection and especially of the treatment of this pathology. In addition, ear-nose-throat-associated (10%) or gastrointestinal/endocrinological (5%) disorders may contribute to the problem. In the case of halitophobia, psychiatrical or psychological problems may be present. Bad breath needs a multidisciplinary team approach: dentists, periodontologists, specialists in family medicine, ear-nose-throat surgeons, internal medicine and psychiatry need to be updated in this field, which still is surrounded by a large taboo.Multidisciplinary bad breath clinics offer the best environment to examine and treat this pathology that affects around 25% of the whole population. This article describes the origin, detection and treatment of halitosis, regarded from the different etiological origins.

Environmental and genetic contributions to indicators of oral malodor in twins

This study aimed to: (1) determine concordance rates of self-reported and subjectively determined indicators of oral malodor in twins; (2) determine the relative contributions of genetic and environmental factors to levels of volatile sulfur compounds (VSCs) in intraoral and exhaled breath. Fifty-one twin pairs participated in the study. Measurements of VSCs were obtained by a halimeter. The presence of tongue coatings was determined and twins filled out a 32-item questionnaire on oral malodor indicators independently of one another. Estimates of heritability (h2) for halimeter measurements were computed by SOLAR. The concordance rates for the presence of tongue coating among identical and fraternal twins were 67% and 11%, respectively. In the 10 most informative items, 70% exhibited higher concordance rates for identical than for fraternal twins. Of particular interest were the differences in concordance rates for dry mouth, sinus infection and unusual sweating. The h2 for intraoral breath was 0.28 +/- 0.17 (NS), whereas the h2 for exhaled breath was 0.50 +/- 0.20 (p = .0207). The concordance rates of tongue coatings and malodor indicators were higher in identical twins than in fraternal twins. Intraoral breath VSC values were primarily attributable to environmental factors, whereas exhaled breath VSC values were partially explained by genetic factors.

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.

Evaluation of oral and extra-oral factors predisposing to delusional halitosis

OBJECTIVE

This study evaluated the role of patients' associated oral and extra-oral factors, as well as previous dental treatment, as possible predisposing (triggering) factors in the development delusional halitosis.

METHOD

Forty-six patients diagnosed of delusional halitosis, over a consecutive period of 2 years (2003-2004) were selected for this study. Diagnosis was based on: use of standard halitosis questionnaire (to confirm the presence of psychological component) modified to obtain data on oral and extra-oral factors, as well as previous dental treatment linked by patients as cause of oral malodour; clinical assessment without objective evidence of oral malodour; absence of reliable third party to confirm patients' claim of oral malodour; and screening with sulphur monitor (RH-17 Series Halimeter, Interscan, Chatsworth, CA) that was within normal range (80-140ppb).

RESULTS

All the 46 patients studied had normal halimeter measurement and no reliable third party to confirm the patients' claim of oral malodour. Twenty-four (52.2%) patients had associated possible predisposing factors. The most common associated factors were bitter taste (25.0%), oral deposits (20.8%), carious tooth (16.7%) and previous tooth extraction (16.7%). Associated factors were divided into oral, extra-oral and dental treatment. Patients' associated oral factors were significantly correlated as predisposing factors for delusional halitosis (p<0.01)

CONCLUSION

This study shows significant correlation of patients' associated oral factors as the triggering event, which could predispose those individuals who may have underlying psychosomatic tendencies to developing delusional halitosis.

Halitosis: A frequently ignored social condition

Halitosis is a common complaint of one third of the population. It is commonly known as ‘bad breath’. The causes of halitosis can both be intraoral (90%) as well as extraoral (10%). Malodor of oral etiology results from the oral cavity itself. Non oral etiology may include various systemic diseases and use of certain drugs. Halitosis can act as a biomarker for various systemic diseases. Organoleptic examination, gas chromatography and portable sulfide monitors are the common methods of measurement of halitosis. Brushing twice daily with tongue cleaning can sufficiently manage halitosis in majority of the population while antimicrobial oral rinses can be prescribed to the non respondents. Necessary investigations and treatment should follow for those having extra oral cause of halitosis.

Extra-oral halitosis: an overview

Halitosis can be subdivided into intra-oral and extra-oral halitosis, depending on the place where it originates. Most reports now agree that the most frequent sources of halitosis exist within the oral cavity and include bacterial reservoirs such as the dorsum of the tongue, saliva and periodontal pockets, where anaerobic bacteria degrade sulfur-containing amino acids to produce the foul smelling volatile sulfur compounds (VSCs), especially hydrogen sulfide (H(2)S) and methyl mercaptan (CH(3)SH). Tongue coating is considered to be the most important source of VSCs. Oral malodor can now be treated effectively. Special attention in this overview is given to extra-oral halitosis. Extra-oral halitosis can be subdivided into non-blood-borne halitosis, such as halitosis from the upper respiratory tract including the nose and from the lower respiratory tract, and blood-borne halitosis. The majority of patients with extra-oral halitosis have blood-borne halitosis. Blood-borne halitosis is also frequently caused by odorous VSCs, in particular dimethyl sulfide (CH3SCH3). Extra-oral halitosis, covering about 5-10% of all cases of halitosis, might be a manifestation of a serious disease for which treatment is much more complicated than for intra-oral halitosis. It is therefore of utmost importance to differentiate between intra-oral and extra-oral halitosis. Differences between intra-oral and extra-oral halitosis are discussed extensively. The importance of applying odor characterization of various odorants in halitosis research is also highlighted in this article. The use of the odor index, odor threshold values and simulation of bad breath samples is explained.

Volatile compounds characteristic of sinus-related bacteria and infected sinus mucus: analysis by solid-phase microextraction and gas chromatography-mass spectrometry

Volatile compounds from human breath are a potential source of information for disease diagnosis. Breath may include volatile organic compounds (VOCs) originating in the nasal sinuses. If the sinuses are infected, disease-specific volatiles may enter exhaled air. Sinus infections are commonly caused by several known bacteria. We examined the volatiles characteristic of infectious bacteria in culture using solid-phase microextraction to collect and gas chromatography-mass spectrometry as well as gas chromatography with flame photometric detection to separate and analyze the resulting VOCs. Infected sinus mucus samples were also collected and their VOCs examined. Similar characteristic volatiles were seen from both cultures of individual "pure" bacteria and several mucus samples. However, the relative amounts of characteristic VOCs from individual bacteria differ greatly between cultures and sinus mucus. New compounds, not seen in culture were also seen in some mucus samples. Our results suggest an important role for growth substrate and environment. Our data further suggests that in some sinus mucus samples identification of bacteria-specific volatiles is possible and can suggest the identity of an infecting organism to physicians. Knowledge of these bacteria-related volatiles is necessary to create electronic nose-based, volatile-specific sensors for non-invasive examination for suspected sinus infection.

Oral Malodour and its Management: A Periodontal Perspective

Halitosis is a very common condition which may affect up to 30% of the population. In most cases the aetiology of the condition is from local oral causes (oral malodour). Oral malodour is the result of the action of anaerobic bacteria in producing a range of malodorous molecular species including volatile sulphur compounds. Patients with halitosis may seek treatment from dental clinicians for their perceived oral malodour. Physiologic halitosis, oral pathologic halitosis and pseudo-halitosis would be in the treatment realm of dental practitioners. Management of oral malodour is directed at managing and reducing the bacterial load both in periodontitis and in tongue coatings by instituting proper oral hygiene measures, control of tongue flora by brushing or scraping, and possibly the adjunctive use of antiseptic agents. Treatments have also been proposed to neutralise malodorous compounds by chemical agents to mask the presence of the condition. Further evidence is required to demonstrate the long-term efficacy of therapies for this troublesome condition. The purpose of this article is to review the etiology, diagnosis and treatment of oral malodor from a periodontal perspective. The review will be limited to bad breath odors originating within the mouth.

Trimethylaminuria (fish-odour syndrome) and oral malodour

A small but important percentage of oral malodour cases have an extra-oral aetiology and certain of these fall into the category of 'blood-borne halitosis'. Odoriferous substances generated within the body and transported to the lungs via the circulatory system may, if sufficiently volatile, leave with the exhaled air and impart a foetid odour to the breath. The aliphatic tertiary amine, trimethylamine, is such a volatile compound that is generated to excess in patients with a metabolic disorder known as trimethylaminuria (fish-odour syndrome). This article highlights this condition and draws attention to its potential role in the causation of recalcitrant oral malodour.

Intra- and extra-oral halitosis: finding of a new form of extra-oral blood-borne halitosis caused by dimethyl sulphide

AIM

The aim of this study was to unravel the origen and cause of intra-oral and extra-oral halitosis.

MATERIAL AND METHODS

We studied 58 patients complaining of halitosis, using gas chromatography of volatile sulphur compounds (VSCs) in mouth and nose breath, organoleptic scoring of mouth and nose breath, Halimeter readings of mouth air and tongue-coating inspection. Subjects had no precence or history of periodontitis.

RESULT

Of 58 patients, 47 patients had halitosis of oral origin, six had halitosis of extra-oral origin and five had no halitosis (halitophobia). A strong correlation was found between the degree of intra-oral halitosis as measured by organoleptic scoring of mouth breath and the concentration of the VSCs hydrogen sulphide (H(2)S) and methyl mercaptan (CH(3)SH) in mouth breath. Taking into account the much larger odour index of CH(3)SH, it was concluded that CH(3)SH is the main contributor to intra-oral halitosis. In all six cases of extra-oral halitosis, halitosis was caused by the presence of elevated levels of dimethyl sulphide (CH(3)SCH(3)) in mouth and nose breath.

CONCLUSION

Our study provides evidence that the VSC, CH(3)SH and to a lesser extent H(2)S are the main contributors to intra-oral halitosis and that CH(3)SCH(3) is the main contributor to extra-oral or blood-borne halitosis, due to a hitherto unknown metabolic disorder.

A review of the current literature on aetiology and measurement methods of halitosis

OBJECTIVES

This work reviews the current knowledge of aetiology and measurement methods of halitosis.

DATA

Halitosis is an unpleasant or offensive odour emanating from the breath. The condition is multifactorial and may involve both oral and non-oral conditions.

SOURCES

A private, monthly with keywords halitosis, malodo(u)r, (a)etiology, measurement, and management from Medline and Pubmed updated database of literature was reviewed.

CONCLUSIONS

In approximately 80-90% of all cases, halitosis is caused by oral conditions, defined as oral malodour. Oral malodour results from tongue coating, periodontal disease, peri-implant disease, deep carious lesions, exposed necrotic tooth pulps, pericoronitis, mucosal ulcerations, healing (mucosal) wounds, impacted food or debris, imperfect dental restorations, unclean dentures, and factors causing decreased salivary flow rate. The basic process is microbial degradation of organic substrates. Non-oral aetiologies of halitosis include disturbances of the upper and lower respiratory tract, disorders of the gastrointestinal tract, some systemic diseases, metabolic disorders, medications, and carcinomas. Stressful situations are predisposing factors. There are three primary measurement methods of halitosis. Organoleptic measurement and gas chromatography are very reliable, but not very easily clinically implemented methods. The use of organoleptic measurement is suggested as the 'gold standard'. Gas chromatography is the preferable method if precise measurements of specific gases are required. Sulphide monitoring is an easily used method, but has the limitation that important odours are not detected. The scientific and practical value of additional or alternative measurement methods, such as BANA test, chemical sensors, salivary incubation test, quantifying beta-galactosidase activity, ammonia monitoring, ninhydrin method, and polymerase chain reaction, has to be established.

Human Breath Odors and Their Use in Diagnosis

Humans emit a complex array of volatile and nonvolatile molecules that are influenced by an individual's genetics, health, diet, and stress. Olfaction is the most ancient of our distal senses and may be used to evaluate food and environmental toxins as well as recognize kin and potential predators. Many body odors evolved to be olfactory messengers, which convey information between individuals. Consequently, those practicing the healing arts have used olfaction to aid in their diagnosis of disease since the dawn of medical practice. Studies using modern instrumental analyses have focused upon analysis of breath volatiles for biomarkers of internal diseases. In these studies, a subject's oral health status appears to seldom be considered. However, saliva and properly collected alveolar air samples must pass over or come in contact with the posterior dorsal surface of the tongue, a site of bacterial plaque development and source of halitosis-related volatiles. Because of our basic research into the nature of human body odors, our lab has received referrals of people with idiopathic malodor production, from either the oral cavity or body. We developed a protocol to help differentiate individuals with chronic halitosis from those with the genetic, odor-producing metabolic disorder trimethylaminuria (TMAU). In our referred population, TMAU is the largest cause of undiagnosed body odor. Many TMAU-positive individuals present with oral symptoms of dysguesia and halitosis as well as body odor. We present data regarding the presentation of our referred subjects as well as the analytical results from a small number of these subjects regarding their oral levels of halitosis-related malodorants and trimethylamine.

The relationship between oral malodor and volatile sulfur compound-producing bacteria

Halitosis can be a crippling social problem, and standard dental treatments and mouthwashes often provide only temporary relief. The mouth is home to hundreds of bacterial species that produce several fetid substances as a result of protein degradation. Volatile sulfur compound (VSC)-producing bacteria colonizing the lingual dorsum have recently been implicated in the generation of halitosis. Detection of VSCs, such as methylmercaptan and hydrogen sulfite, via organoleptic and objective methods, can aid in the identification of their source. Following comprehensive evaluation for possible causes, most halitosis in patients seen in an ENT practice can be localized to the tongue. We review methods of diagnosis and treatment of oral malodor from the overgrowth of proteolytic, anaerobic, gram-negative bacteria on the crevices of the lingual dorsum. Bacteriologic analysis of biofilm and scraped specimens obtained from the lingual dorsum and other oral sites, primarily gingival pockets and tonsillar crypts, can identify VSC-producing bacteria. Porphyromonas, Prevotella, Actinobacillus, and Fusobacterium species are the most common organisms identified. Halitosis is an oral phenomenon, with almost no cases originating distal to the tonsils. Halitosis arising from the lingual dorsum secondary to overpopulated VSC-producing bacteria can be successfully managed with a combination of mechanical cleansing using tongue brushes or scrapes and chemical solutions containing essential oils, zinc chloride, and cetylpyridinium chloride.

Factors associated with self-reported halitosis in Kuwaiti patients

OBJECTIVES

Oral malodor is a common complaint of dental patients, yet limited data is available on the actual prevalence of this condition. The aim of this study was to assess the prevalence and factors associated with self-reported halitosis in Kuwaiti patients.

METHODS

This was a cross-sectional study of Kuwaiti adults using a 19-point self-administered structured questionnaire on self-perception of halitosis. Significant associations between self-reported oral malodor and sociodemographic, medical history, and oral hygiene variables were examined with multiple logistic regression analysis.

RESULTS

A total of 1551 subjects participated (response rate=86.2%). The prevalence of self-reported halitosis was 23.3%. Use of the toothbrush less than once daily was the factor most strongly associated with self-perceived halitosis (OR=2.68; 95% CI=1.83-3.92; p<0.001). Other factors significantly associated with self-perceived halitosis included current or past smoking (OR=2.51), female gender (OR=1.54), being 30 years of age or older (OR=1.35), having high school education or less (OR=1.41), history of chronic sinusitis (OR=1.58) or gastrointestinal disorders (OR=1.73), never using miswak (OR=1.56), and never using dental floss (OR=1.33).

CONCLUSION

Inadequate oral hygiene practices were the factors most strongly associated with self-reported oral malodor in this sample of Kuwaiti patients. Other factors with significant associations included history of gastrointestinal tract disorders, chronic sinusitis, older age, female gender, and lower education levels.

A cross-over study on the effect of various therapeutic approaches to morning breath odour

OBJECTIVE

The aim of this study was to investigate the effect of tongue scraping and inter-dental flossing on morning bad breath in periodontally healthy subjects.

METHODS

A four-step blind, cross-over study was conducted in 19 volunteers, divided into four groups: Group I: tooth brushing; Group II: tooth brushing and inter-dental flossing; Group III: tooth brushing and tongue scraping; and Group IV: tooth brushing, inter-dental flossing and tongue scraping. The volunteers performed these oral hygiene procedures three times a day for 7 days. Seven-day wash-out intervals were observed. Morning mouth breath was assessed organoleptically and by volatile sulphur compound concentrations.

RESULTS

The highest mean organoleptic and volatile sulphur compound measurement values were found in the treatment groups in which tongue scraping was not performed and there were statistical differences between the two groups (p < 0.05). In the organoleptic evaluation (p > 0.05), inter-dental flossing did not show any statistical improvement in the effect of tongue hygiene on morning bad breath, but it significantly reduced the concentration of volatile sulphur compounds (p < 0.05).

CONCLUSION

The findings suggest that tongue scraping appears to be the most important hygienic procedure to reduce morning bad breath in periodontally healthy subjects.

Comparisons between mammalian and artificial olfaction based on arrays of carbon black-polymer composite vapor detectors

Arrays of broadly cross-reactive vapor sensors provide a man-made implementation of an olfactory system, in which an analyte elicits a response from many receptors and each receptor responds to a variety of analytes. Pattern recognition methods are then used to detect analytes based on the collective response of the sensor array. With the use of this architecture, arrays of chemically sensitive resistors made from composites of conductors and insulating organic polymers have been shown to robustly classify, identify, and quantify a diverse collection of organic vapors, even though no individual sensor responds selectively to a particular analyte. The properties and functioning of these arrays are inspired by advances in the understanding of biological olfaction, and in turn, evaluation of the performance of the man-made array provides suggestions regarding some of the fundamental odor detection principles of the mammalian olfactory system.

Effect of tongue brushing on oral malodor in adolescents

BACKGROUND

Halitosis is a common problem in humans, and is a social and psychological handicap for those affected by it. Halitosis has a positive correlation with the accumulation of bacterial plaque in the oral cavity.

AIMS

The aim of the present study was to determine the effect of tongue brushing on oral malodor in adolescents.

METHODS

The subjects of the investigation were 28 adolescents who had oral malodor and whose average age was 16 +/- 0.12 years. Subjects were chosen to participate in the study if they had an established routine of oral care, and did not have systemic or periodontal disease or dentures (such as fixed prosthesis or partial and total dentures). The subjects with oral malodor were randomly assigned into two groups. Individuals in the first group received instructions regarding professional procedures of oral care from a periodontist. In addition, individuals in this group had the surface of their tongue cleaned using a hard toothbrush, wetted with 0.12% chlorhexidine gluconate. Individuals in the second group (control) underwent the same professional procedures of oral care executed by the same periodontist, however, they did not have their tongues cleaned. Oral malodor of individuals was then evaluated for all individuals using the organoleptic method. The pH of the subjects tongues were recorded before and after treatment. The results of the oral malodor test were compared between the two groups.

RESULTS

The results of the study found that oral malodor scores obtained by an organoleptic method was more severe in the second group than the first group, and statistical differences were found between the two groups (P < 0.001).

CONCLUSION

These results revealed that accumulation of bacterial plaque on the tongue is an important factor for oral malodor in the adolescents. Oral malodor levels were significantly reduced after cleaning the surface of the tongue. Thus, tongue care shouldn't be neglected in order to avoid oral malodor.

Enhanced sensitivity to and classification of volatile carboxylic acids using arrays of linear poly(ethylenimine)-carbon black composite vapor detectors

Vapor detectors formed from composites of conductors and insulating organic polymers have been tailored to produce increased sensitivity toward specific classes of analyte vapors. Upon exposure to acetic acid at 1% of its vapor pressure, detectors consisting of linear poly(ethylenimine) (1-PEI)-carbon black composites showed an approximately 10(3) increase in signal/noise relative to the performance of typical insulating organic polymer-carbon black composite vapor detectors. Compositional diversity in an array of such vapor detectors was obtained by varying the degree of plasticization of the 1-PEI films. The resulting vapor detector array produced sensitive detection of, and robust discrimination between, various volatile organic acids and relatively little response from nonacidic organic vapors or from water vapor. Measurements of the mass uptake, thickness change, and electrical conductivity of such composites indicate that swelling of the polymer film, and thus its normalized resistance response, is beyond that expected by mass uptake alone upon exposure to acetic acid vapor. This additional thickness increase is attributed to charge-induced polymer swelling occurring from polymer-analyte interactions. Electrical percolation also plays a significant role in producing the large increase in normalized resistance response of these composites upon exposure to acetic acid vapor.

Relationship between stressful situations, salivary flow rate and oral volatile sulfur-containing compounds

The relationship between stress, salivary flow rate and oral volatile sulfur-containing compounds (VSCs) is not clearly established. Two stressful situations were studied: psychological stress caused by a biochemistry examination (Study I) and psychophysiological stress caused by premenstrual syndrome (PMS) (Study II). Seventy-one undergraduate dental students took part in Study I and VSCs were measured 1 wk before the examination, on the day of examination and 1 wk after. In Study II, 50 women were selected (23 with and 27 without PMS) and the measurements were made during non-menstrual, premenstrual and menstrual stages. Unstimulated salivary flow was determined in the subjects of both studies. On the day of the biochemistry examination, VSCs significantly increased and salivary flow decreased compared with baseline values. Women with PMS showed higher VSC concentrations during the premenstrual stage than those without PMS (P < 0.05), but the salivary flow was not statistically different. A change in VSCs was observed during different stages of the menstrual cycle for the groups of women, but the salivary flow did not change. The results suggest that a stressful situation can be a predisposing factor for the increase of VSCs in the mouth air, but the mechanism cannot be simply explained by reduction of the salivary flow.

Halitosis in medicine: a review

This review deals with the different forms of halitosis. Halitosis can be subdivided according to its original location. At present, halitosis of oral origin is quite well understood and some excellent reviews have already appeared in the literature. Special attention is given here to extra-oral halitosis. Extra-oral halitosis can be subdivided into: halitosis from the upper respiratory tract including the nose; halitosis from the lower respiratory tract; blood-borne halitosis. In blood-borne halitosis, malodourant compounds in the bloodstream are carried to the lungs where they volatilise and enter the breath. Potential sources of blood-borne halitosis are some systemic diseases, metabolic disorders, medication and certain foods. The methods of analysis of halitosis are critically reviewed. Attention is also given to odour characterisation of various odourants.

Assessment of newly developed tongue sulfide probe for detecting oral malodor

AIM

The present study examined the relationship between sulfide levels on tongue dorsum surfaces (pS levels) and oral malodor.

METHOD

The pS levels of 20 systemically healthy volunteers were evaluated using an industrial device equipped with a newly-developed tongue sulfide probe. The pS levels on 3 parts of the tongue--anterior, middle and posterior along the median groove of the tongue dorsum--were determined for each subject.

RESULTS

The device reported the pS level in a digital score ranging from 0.0 (< 10(-7) M of sulfide) to 5.0 (> or = 10(-2) M of sulfide) in increments of 0.5. Oral malodor was assessed by measuring the level of volatile sulfur compounds in mouth air, as well as by the organoleptic method. The pS levels were 0.03 +/- 0.11, 0.20 +/- 0.41 and 0.88 +/- 0.76 for the anterior, middle and posterior parts, respectively. This difference was significant (p<0.001). Both oral malodor measurements showed significant correlation (p<0.05) with the pS levels of middle and posterior parts of tongue.

CONCLUSION

It was concluded that the tongue sulfide probe might be useful in management of subjects with oral malodor.

Relationship between sulcular sulfide level and oral malodor in subjects with periodontal disease

BACKGROUND

The relationship between oral malodor and sulfide levels in periodontal pockets (pS) has not yet been determined. The aims of this study were: 1) to identify the correlation among oral malodor, pS levels, and the BANA (benzoyl-DL-arginine-naphthylamide) test and 2) to recognize the interaction between oral malodor, demographic factors, tongue coating, and periodontal condition.

METHODS

Eighty-one periodontal patients participated in this study. A portable sulfide monitor and organoleptic method were used to evaluate oral malodor. Demographic data included age, gender, race, and smoking habits. The volume of tongue coating and periodontal condition for all teeth were assessed. The pS levels of 3 different radiographic bone loss (RBL) sites: RBL < 2 mm, healthy; RBL > or = 2 to < 4 mm; low to moderate; RBL > or = 4 mm, severe, were measured using an industrial sulcular sulfide-monitoring device. Subgingival plaque samples from the above 3 sites and tongue scraping were examined by the BANA test.

RESULTS

The volume of tongue coating (P<0.001), extent of periodontal disease (P<0.05), pS levels of the sites with low to moderate bone loss (P<0.05), and BANA score of tongue scrapings (P<0.05) were significantly associated with oral malodor. Stepwise multiple regression analysis examined the degree of association between oral malodor and potential explanatory variables. The volume of tongue coating and percent of sites BOP (bleeding on probing) were significantly associated with oral malodor. Females and smoking habit were negatively correlated with organoleptic measurements.

CONCLUSIONS

The pS level of the representative sites with low to moderate bone loss demonstrated a modest association with oral malodor. Oral malodor in periodontal patients was primarily associated with tongue coating and gingival inflammation.

Quantification of hydrogen sulphide in humid air by selected ion flow tube mass spectrometry

We report the results of a study of the reactions of H(3)O(+), NO(+) and O(2)(+.) ions with H(2)S. This study was undertaken to provide a thorough understanding of the ion chemistry required for accurate quantification of H(2)S in humid air by selected ion flow tube mass spectrometry (SIFT-MS). It shows that slow reactions occur between H(3)S(+), the primary product ions of the H(3)O(+)/H(2)S reaction, and the abundant H(2)O molecules present in humid air and breath. These reactions disturb somewhat the quantification of H(2)S by this analytical method, but the kinetic data obtained in this study facilitate precise quantification of H(2)S in humid air. This study also shows that NO(+) does not react with H(2)S, and that O(2)(+.) does react rapidly with H(2)S, but the product H(2)S(+.) ions react rapidly with H(2)O. Thus, NO(+) and O(2)(+.) cannot be used as precursor ion for analysis of H(2)S in moist air by SIFT-MS. A sample SIFT mass spectrum is shown from which H(2)S and several other volatile compounds have been quantified in a sample of cow rumen gas.

Olfactory sensitivities of mosquitoes with different host preferences (Anopheles gambiae s.s., An. arabiensis, An. quadriannulatus, An. m. atroparvus) to synthetic host odours

Responses of antennal olfactory cells associated with sensilla trichodea were recorded in females of four Anopheles species (Diptera, Culicidae) with different host preferences: the anthropophilic An. gambiae s.s., the opportunistic An. arabiensis, and the zoophilic An. quadriannulatus and An. maculipennis atroparvus. Stimuli were vapours of synthetic host-odours: ethanoic, propanoic, butanoic, 3-methyl propanoic, 4-methyl butanoic acid, 1-octen-3-ol, and 3- and 4-methyl phenol. On stimulation with fatty acids and phenols either excitation or inhibition of spike activity was found, whereas responses to 1-octen-3-ol were invariably excitatory. The odour spectra of the cells could include activating as well as inhibiting substances. Differences in host preferences may be reflected in the numbers of olfactory cells responding to different odours and/or in the sensitivities of these cells. In An. gambiae more cells were excited by fatty acids than in An. arabiensis and An. m. atroparvus, whereas inhibition occurred more often in the latter two species. In addition, the fatty acid-excited cells in An. gambiae were more sensitive to these substances than in An. m. atroparvus and An. quadriannulatus. On the contrary, in the latter two species cells were more responsive to 1-octen-3-ol. In An. arabiensis, responses of stimulus-excited cells were intermediate between those in the anthropophilic and zoophilic species.

Trimethylaminuria is caused by mutations of the FMO3 gene in a North American cohort

Trimethylaminuria (TMAuria) (McKusick 602079) first described in 1970 is an autosomal recessive condition caused by a partial or total incapacity to catalyze the N-oxygenation of the odorous compound trimethylamine (TMA). The result is a severe body odor and associated psychosocial conditions. This inborn error of metabolism, previously thought to be rare, is now being increasingly detected in severe and milder presentations. Mutations of a phase 1 detoxicating gene, flavin-containing monooxygenase 3 (FMO3), have been shown to cause TMAuria. Herein we describe a cohort of individuals ascertained in North America with severe TMAuria, defined by a reduction of TMA oxidation below 50% of normal with genotype-phenotype correlations. We detected four new FMO3 mutations; two were missense (A52T and R387L), one was nonsense (E314X). The fourth allele is apparently composed of two relatively common polymorphisms (K158-G308) found in the general population. On the basis of this study we conclude that one common mutation and an increasing number of private mutations in individuals of different ethnic origins cause TMAuria in this cohort.

Differentiation of mouth versus gut as site of origin of odoriferous breath gases after garlic ingestion

Utilizing the sulfur-containing gases of garlic as probes, we investigated the gut versus mouth origin of odoriferous breath gases. Five individuals ingested 6 g of garlic, and sulfur gases in mouth, alveolar air, and urine samples were measured. The mouth normally contained low concentrations of hydrogen sulfide, methanethiol, and dimethyl sulfide. Immediately after garlic ingestion, transient high concentrations of methanethiol and allyl mercaptan and lesser concentrations of allyl methyl sulfide (AMS), allyl methyl disulfide, and allyl disulfide were observed. With the exception of AMS, all gases were present in far greater concentrations in mouth than alveolar air, indicating an oral origin. Only AMS was of gut origin as evidenced by similar partial pressures in mouth, alveolar air, and urine. After 3 h, AMS was the predominant breath sulfur gas. The unique derivation of AMS from the gut is attributable to the lack of gut and liver metabolism of this gas versus the rapid metabolism of the other gases. Breath odor after garlic ingestion initially originates from the mouth and subsequently from the gut.

Oral malodor and its relevance to periodontal disease in the dog

Oral malodor has been studied extensively in humans but very little work has been done in dogs where it constitutes a significant problem. In this article we review its causes, methods of detection, and strategies for preventing it. Oral malodor arises from microbial metabolism of exogenous and endogenous proteinaceous substrates in the oral cavity and is exacerbated by periodontal disease and poor oral hygiene. Gram negative bacteria found in plaque, in periodontal pockets, and on the dorsum of the tongue are primarily responsible for odor production. The volatile sulfur compounds (VSCs) hydrogen sulfide and methyl mercaptan, which are produced by these bacteria, are not only primarily responsible for the objectionable odor but have been implicated in the pathogenesis of periodontal disease. Assessment of malodor by portable sulfide monitors correlates well with organoleptic measurements. Reduction of microbial load in the oral cavity due to good oral hygiene practices (such as tooth-brushing) or by the use of appropriate diets or chews may reduce malodor formation.

Chemosensory function and dysfunction

Taste and smell are fundamental sensory systems essential in nutrition and food selection, for the hedonic and sensory experience of food, for efficient metabolism, and, in general, for the maintenance of a good quality of life. The gustatory and olfactory systems demonstrate a diversity of transduction mechanisms, and during the last decade, considerable progress has been made toward our understanding of the basic mechanisms of taste and smell. Understanding normal chemosensory function helps clarify the molecular events that underlie taste and smell disorders. At least 2,000,000 Americans suffer from chemosensory disorders--a number that is likely to grow as the aging segment of the population increases. Smell disorders are more frequent than taste disturbances, due to the vulnerability and anatomical distinctiveness of the olfactory system, and because a decline in olfactory function is part of the normal aging process. Common gustatory and olfactory complaints are due to a number of medications, to upper respiratory infections, to nasal and paranasal sinus diseases, and to damage to peripheral nerves supplying taste and smell. Most chemosensory complaints have an identifiable cause. Although diagnosis of taste and smell disorders has improved considerably over the last two decades, treatment of these disorders is still limited to conditions with discernible and reversible causes. Future research is needed for a better understanding of chemosensory mechanisms, establishing improved diagnostic procedures, and disseminating knowledge on chemosensory disorders among practitioners and the general public.

The application of infrared spectroscopy to breath CO2 isotope ratio measurements and the risk of spurious results

Stable CO2 isotope breath tests are established as a valuable tool in diagnostic and investigative medicine with the potential to become more prominent in the future. However, their development and widespread clinical use is limited by the requirement of isotope ratio mass spectroscopic analysis. To overcome this restriction alternative analytical techniques have been developed; the most promising, offering relative simplicity and lower costs, are those instruments using infrared spectroscopy. Clinical investigations using such instruments show them to perform well but very little attention has been given to the possibility of interference from the infrared absorption spectrum of other compounds in the breath. To provide an unambiguous answer to this concern we have analysed literature on over 200 detected breath compounds and their infrared absorption spectra to identify any absorption bands coincident with the nu3 absorption band of CO2. It was found that only five breath trace compounds possess coincident fundamental absorption bands, none of which pose the risk of spurious results. We conclude that the 13C16O2/12C16O2 ratio can confidently be measured for isotopic breath tests using an infrared spectrometer, the position of the nu3 absorption band of CO2 in the infrared spectrum precluding any discernible risk of spurious measurements due to coincidental absorption bands.

Clinical assessment of bad breath: current concepts

Bad breath typically originates in the mouth, often from the back of the tongue. Nasal problems also can cause bad breath; odor generated in this manner can be easily distinguished from mouth odor by comparing the odor exiting the mouth and nose. In most cases, good professional oral care combined with a daily regimen of oral hygiene--including interdental cleaning, deep tongue cleaning and optional use of an efficacious mouthrinse---will lead to improvement. This article discusses common causes of oral malodor as well as methods to assess the extent of the problem.

Adverse effects of mouthwash use. A review

Many persons use mouthrinses as a part of their routine oral hygiene. Although rinses impart some benefits to users, improper use of mouthrinses may result in various side effects. This paper reviews the adverse effects of mouthwash use as reported in the English-language literature.