Halitosis - An overview: Part-I - Classification, etiology, and pathophysiology of halitosis

One-Step Synthesis of Hydrogel Adhesive with Acid-Responsive Tannin Release for Diabetic Oral Mucosa Defects Healing

The complex preparation, weak wet tissue adhesion, and limited biological activity of traditional oral wound dressings usually impede their efficient treatment and healing for diabetic oral mucosal defects. To overcome these problems, a novel hydrogel adhesive (named CFT hydrogel) is rapidly constructed using a one-step method based on dual-dynamic covalent cross-linking. Compared with the commercial oral patches, the CFT hydrogel shows superior in vivo (rat tongue) wet tissue adhesion performance. Additionally, the CFT hydrogel exhibits unique acid-responsive properties, thereby facilitating the release of bioactive molecule tannic acid in the acidic diabetic wound microenvironment. And a series of in vitro experiments substantiate the favorable biocompatibility and bioactivity properties (including antibacterial, antioxidative, anti-inflammatory, and angiogenetic effects) exhibited by CFT hydrogel. Moreover, in vivo experiments conducted on a diabetic rat model with oral mucosal defects demonstrate that the CFT hydrogel exhibits significant efficacy in protecting against mucosal wounds, alleviating inflammatory reactions, thereby facilitating the wound-healing process. Taken together, this study provides a promising and comprehensive therapeutic option with great potential for the clinical management of oral mucosa defects in diabetic patients.

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.

Oxidative Stress and Natural Products in Orthodontic Treatment: A Systematic Review

In recent years, orthodontics, a specialized branch of dentistry, has evolved considerably in terms of both techniques and materials used. Aimed at correcting dental malocclusions and craniofacial anomalies, it improves the functionality and aesthetics of the face and oral cavity. However, orthodontic treatment, in its developmental stages, may induce oxidative stress (O.S.) phenomena, with an increase in the production of reactive oxygen species (ROS), damaging the dental and periodontal tissues involved, affecting the short-, medium- and long-term results. Studies on the antioxidant effects of natural products (e.g., resveratrol, green tea, turmeric, etc.) in the medical field have aroused considerable interest in recent years. A systematic literature review was conducted on the PubMed, Scopus, and Web of Science databases using natural products (N.P.s), O.S., and orthodontic as keywords. The study aims to consider the determinants of the increase in ROS occurring during orthodontic treatment and the possibility of natural products being able to control and neutralize biochemical phenomena by restoring the physiological process in which the balance between the production of ROS and the ability of the body's antioxidant system to neutralize them is in favor of the latter.

Oral microbiome as a co-mediator of halitosis and periodontitis: a narrative review

Objective

Halitosis or oral malodor is an unpleasant odor from the oral cavity. However, although patients with periodontitis often complain of halitosis, their relationship has not been fully elucidated. We reviewed previous literature based on the hypothesis that the relationship between halitosis and periodontitis is mediated by the oral microbiome.

Materials and methods

This narrative review sought to provide insight into the causative role of the oral microbiome in influencing halitosis and periodontitis. In addition, we tried to deepen knowledge related to the relationship between halitosis and periodontitis generated by the oral microbiome accumulated over the past 40 years.

Results

From 1984 to 2023, a total of 106 papers that carefully and scientifically dealt with halitosis and periodontitis were included in this narrative review. Based on previous results, halitosis and periodontitis were closely related. For decades, researchers have taken an intriguing approach to the question of whether there is a relationship between halitosis and periodontitis. Central factors in the relationship between halitosis and periodontitis include volatile sulfur compounds (VSCs), the oral microbiota that produce VSCs, and the inflammatory response.

Conclusions

Taken together, the more severe periodontitis, the higher the level of VSC in halitosis, which may be mediated by oral microbiome. However, the relationship between the occurrence, maintenance, and exacerbation of periodontitis and halitosis is not a necessary and sufficient condition for each other because they are complex interplay even in one individual.

Investigation of volatile sulfur compound level and halitosis in patients with gingivitis and periodontitis

This study aimed to measure the levels of volatile sulfur compounds and investigate the occurrence of halitosis in patients with gingivitis and periodontitis. Additionally, the incidence rates of gingivitis and periodontitis in patients with halitosis were investigated. Through various statistical analyses, we attempted to determine the relationship between periodontal disease and halitosis. One-hundred-and-four participants (52 females and 52 males, mean age: 46.49 ± 16.03 years) were enrolled in this cross-sectional study, comprising 33 healthy controls, 43 patients with gingivitis, and 28 patients with periodontitis. Gas chromatography was used to measure hydrogen sulfide (H2S) and methyl mercaptan (CH3SH), which are representative VSCs. The VSC cut-off values for diagnosing halitosis were 65.79 ppb for women and 79.94 ppb for men. Total VSC level was significantly higher in the gingivitis than the healthy control group (186.72 ± 374.83 ppb vs. 19.80 ± 40.19 ppb, p = 0.035). There was no significant difference between the gingivitis and periodontitis (153.79 ± 278.51 ppb) groups. H2S level was significantly higher in the gingivitis (100.51 ± 183.69 ppb) and periodontitis (91.57 ± 132.06 ppb) groups than in healthy controls (14.97 ± 31.22 ppb), and CH3SH level was significantly higher in gingivitis group (29.31 ± 59.16 ppb) than in the healthy control (5.73 ± 14.10 ppb) (all p < 0.05). Halitosis was found in 3% of healthy controls and 39.5% and 42.9% of patients with gingivitis and periodontitis patients, respectively, making it significantly higher in the gingivitis and periodontitis groups than the healthy controls (p = 0.005). Conversely, among participants with halitosis, 53.1% had gingivitis, 37.5% had periodontitis, and 90.6 incidence had periodontal disease. Multivariate logistic regression analysis to predict the presence of halitosis, found periodontal disease was a significant predictor of halitosis (OR = 3.607, 95% CI 1.023-12.718, p = 0.046). Considering area under curve value for halitosis, the cut-off value of healthy control (H2S:61.5 ppb, CH3SH:3.5 ppb), gingivitis (H2S:50.0 ppb, CH3SH:6 ppb), and periodontitis (H2S:62.0 ppb, CH3SH:3.5 ppb) were (all p < 0.05). Our results emphasize the close and strong relationship between periodontal disease and halitosis through human clinical evidence based on the high co-occurrence rate of mutual diseases. Additionally, the presence of periodontal disease increased the probability of halitosis by 3.607 times. These results suggest that H2S can be used as a biomarker of halitosis in patients with periodontal disease.

Clinical and oral microbiome pattern of halitosis patients with periodontitis and gingivitis

Halitosis is caused by a bacterial proteolytic process that induces the production of volatile sulfur compounds, odor-causing gases. The aim of this study was to determine the clinical oral hygiene state and oral microbiome pattern of halitosis patients with periodontitis and gingivitis. The oral hygiene state of halitosis patients with periodontitis and gingivitis was assessed using the oral hygiene index simplified (OHI-S), decay missing filled teeth (DMFT), and tongue biofilm. The dorsum of the tongue and subgingival swabs were cultured for bacteria, and bacterial morphology was evaluated using Gram staining. Evaluation of the bacterial genus using the Bergey's systematic bacteriology diagram as a guide. A total of ten patients with periodontitis and gingivitis were included. Our data indicated that the scores of OHI-S and DMFT were different significantly between halitosis patients with periodontitis and gingivitis (both had p<0.001) while tongue biofilm score was not different between groups. On the dorsum of the tongue, periodontitis patients had a significant higher oral microbiome population (85.65x106 CFU/mL) compared to those with gingivitis (0.047x106 CFU/mL) with p=0.002. In contrast, the number of microbiomes in the subgingival had no significant different between periodontitis and gingivitis. On the dorsum of the tongue, six bacterial genera were isolated from periodontitis cases and seven genera were detected from gingivitis patients. On subgingival, 10 and 15 genera were identified from periodontitis and gingivitis, respectively. Fusobacterium, Propionibacterium, Eubacterium and Lactobacillus were the most prevalent among periodontitis cases while Porphyromonas was the most prevalent in gingivitis patients. In conclusion, although OHI-S and DMFT are different between periodontitis and gingivitis, overlapping of bacterial genera was detected between periodontitis and gingivitis cases.

Relationship between Hormonal Changes and Self-Perceived Halitosis in Females: A Cross-Sectional Study

Halitosis is a growing concern for patients seeking dental treatment. Women experience hormonal changes throughout different phases of their life. These changes may affect volatile organic compound (VOC) production and can be linked to halitosis. The aim of this study was to evaluate the effect of hormonal changes on self-perceived halitosis in a sample of females using a self-administered questionnaire. This study used a cross-sectional observational design. The questionnaire was distributed electronically through Google forms. A total of 1089 participants completed the questionnaire. Almost 50% of participants were below the age of 25; and 12% were of menopausal age (defined as 45 years and older). Most participants reported having regular menstrual cycles (63.5%) while only 20% reported having hormonal disturbances. Almost 62% of the sample reported that they notice halitosis on themselves with 27.6% indicating their perception of halitosis occurred at different times of the month. Around 12% of the sample thought that a relationship between halitosis and their menstrual cycle existed with 4.6% reporting halitosis during menstruation. The present study found that regularity of menstrual cycle and hormonal disturbances can affect females' self-perceived halitosis and the prevalence of oral health symptoms.

Efficacy of probiotics in the management of halitosis: a systematic review and meta-analysis

BACKGROUND

Halitosis is defined as a foul odour emitted from the oral cavity. Many interventions have been used to control halitosis from mouthwashes to chewing gums. Probiotics have been reported as an alternative method to alleviate halitosis.

OBJECTIVE

The present study aimed to investigate the effect of probiotics on halitosis from a time perspective.

DESIGN AND METHODS

This is a meta-analysis study performed in indexed databases up to February 2021. Randomised controlled trials that compared the effects of probiotics and placebo on primary outcomes (organoleptic (OLP) scores and volatile sulfur compound (VSC) levels) and secondary outcomes (tongue coating scores (TCS) and plaque index (PI)) were included. Data extraction and quality assessment were conducted independently by two reviewers. Publication bias and leave-one-out analyses were performed.

RESULTS

The standardised mean difference (SMD) and 95% CI were calculated to synthesise data. The data were subgrouped and analysed in the short term (≤4 weeks) and long term (>4 weeks) based on the follow-up time. Seven articles were included in this meta-analysis. The primary outcomes, OLP scores (SMD=-0.58; 95% CI -0.87 to -0.30, p<0.0001) and VSC levels (SMD=-0.26; 95% CI -0.51 to -0.01, p=0.04), both decreased significantly in the probiotics group compared with the placebo group in the short term. However, a significant reduction was observed only in OLP scores (SMD=-0.45; 95% CI -0.85 to -0.04, p=0.03) in the long term. No significant differences were observed in secondary outcomes. There was no evidence of publication bias. The leave-one-out analysis confirmed that the pooled estimate was stable.

CONCLUSIONS

According to the results of this work, it seems that probiotics (eg, Lactobacillus salivarius, Lactobacillus reuteri, Streptococcus salivarius and Weissella cibaria) may relieve halitosis in the short term (≤4 weeks). The results of the biased assessment, limited data and heterogeneity of the clinical trials included might reduce the reliability of the conclusions.

Self-Perceived Halitosis and Related Factors Among the Mask-Wearing Population During the COVID-19 Pandemic in Delhi, India: A Cross-Sectional Study

Introduction Halitosis (oral malodor) is a common health condition throughout the world. In India, data on self-reported halitosis and related factors is limited. Mouth mask usage has been made compulsory after the coronavirus disease 2019 (COVID-19) pandemic. This could possibly alter oral microflora and environment and contribute to halitosis. The aim of the study was to determine the prevalence of self-perceived halitosis (SPH) among mask-wearing patients visiting a tertiary care dental hospital in Delhi, India. Methods A cross‑sectional study was conducted among a convenience sample of 300 patients visiting a tertiary care dental hospital in the capital of India. SPH status was measured using a self-designed and structured questionnaire containing socio-demographic factors, mask-related habits, and self-perceived oral health status. Statistical analysis was done using Jamovi software (The jamovi project, Sydney, Australia) version 1.8. Descriptive analysis followed by a chi-square test and a multivariate logistic regression test was applied. Results Bad breath was perceived by 86 study subjects. Of the participants, 16.7% felt that they had bad breath before the pandemic, and 38% of the participants had an increased perception or feeling of bad breath since regular mask usage. Of the participants, 42.7% felt that they had an increased feeling of dryness in the mouth post-pandemic. SPH status was associated with mask usage frequency (p<0.001), change (p<0.001) and type of mask (p=0.004), increased feeling of dryness (p<0.001), frequency of toothbrushing (p<0.001), self-reported oral disease (p=0.007), and dental treatment in the past 12 months (p=0.005). Conclusion The SPH status of the study population was associated with mask-related habits and self-reported oral health status. The findings highlight the importance of possible amendments in preventive and curative care for patients with halitosis post-COVID-19 pandemic.

Diversity of Oral Microbiome of Women From Urban and Rural Areas of Indonesia: A Pilot Study

Objective: The studies on the influence of geographical and socio-economic factors on the oral microbiome remain underrepresented. The Indonesia basic health research (RISKESDAS) 2018, showed an increasing trend in non-communicable diseases compared with the previous report in 2013. The prevalence of diabetes, heart disease, hypertension, and obesity are reported to be higher in urban areas than in rural areas. Interestingly, non-communicable diseases were found to be more prevalent in women than men. This pilot study aimed to examine the oral health and oral microbiome derived from tongue samples of healthy Indonesian women from urban and rural areas. Methods: Twenty women aged 21-47 years old from West Jakarta, residents of DKI Jakarta (n = 10) as representative of the urban area, and residents of Ende, Nangapanda, East Nusa Tenggara (n = 10) as representative of the rural area were recruited for this pilot study. The participants were evaluated by the Simplified Oral Hygiene Index (OHI-S) according to the criteria of Greene and Vermillion and divided into three groups. High-throughput DNA sequencing was performed on an Illumina iSeq 100 platform. Results: The principal component analysis displayed a marked difference in the bacterial community profiles between the urban and rural localities. The presence of manifest was associated with increased diversity and an altered oral bacterial community profile in the urban women. Two bacterial taxa were present at significantly higher levels (adjusted p < 0.01) in the urban oral microflora (Genus Prevotella and Leptotricia) could account for this difference irrespective of the individual oral hygiene status. The linear discriminant analysis effect size (LEfSe) analysis revealed several distinct urban biomarkers. At the species level, Leptotrichia wadei, Prevotella melaninogenica, Prevotella jejuni, and P. histicola, show an excellent discriminatory potential for distinguishing the oral microflora in women between urban and rural areas. Further, using SparCC co-occurrence network analysis, the co-occurrence pattern in the dominant core oral microbiome assembly was observed to be specific to its ecological niche between two populations. Conclusions: This is the first pilot study demonstrating the characterization of the oral microbiome in Indonesian women in urban and rural areas. We found that the oral microbiome in women displays distinct patterns consistent with geographic locality. The specific characterization of the microbiota of Indonesian women is likely linked to geographical specific dietary habits, cultural habits, and socio-economic status or the population studied.

Self-perceived and self-reported breath odour and the wearing of face masks during the COVID-19 pandemic

Objectives

To assess the self‐perception of breath odour (SPBO) and oral hygiene habits (OHHs) while the wearing of face masks during the COVID‐19 pandemic.

Subjects and Methods

This cross‐sectional study included 4647 individuals who answered a structured questionnaire containing demographic, medical and dental variables and self‐perceived breath odour. Variables associated with changes in self‐perceived breath odour, self‐perceived halitosis and changes in OHHs were assessed through multivariate logistic regression.

Results

Changes in self‐perceived breath odour were reported by 1572 individuals and were associated with smoking, systemic conditions, dry mouth, tongue coating, the period of face mask use and its interaction with prior thinking of having bad breath. Likewise, 645 individuals started to consider having bad breath. This was associated with the interaction between prior family/friends saying they have bad breath and period of face mask use. Changes in OHHs were strongly associated with changes in SPBO and starting to consider having bad breath.

Conclusion

Changes in one's SPBO was associated with the wearing of face masks and was significant for changes in OHHs. Findings may be important to guide comprehensive preventive and therapeutic strategies in relation to oral health care.

Alleviation of halitosis by use of probiotics and their protective mechanisms in the oral cavity

Regarding the relation of halitosis with oral infections and its effects on social relations between humans, the present study investigated the positive effects of probiotics on prevention or treatment of halitosis. The causative agents of halitosis are volatile sulphur compounds (VSCs), and halitosis is divided into oral and non-oral types according to the source of the VSCs. H2S and CH3SH are two main halitosis metabolites-produced following the degradation of proteins by bacteria in the mouth-however, CH3SCH3 has a non-oral origin, and is a blood neutral molecule. Just as much as halitosis is important in medicine, its psychological aspects are also considered, which can even lead to suicide. Today, the use of probiotics as a new therapeutic in many roles is in progress. Most probiotics are used for the treatment of gastrointestinal tract disorders, but various studies on the alleviation of halitosis by use of probiotics have reported satisfactory results. The genera Lactobacillus, Streptococcus and Weissella are among the most useful probiotics for the prevention or treatment of halitosis in the oral cavity.

Adolescence, Adulthood and Self-Perceived Halitosis: A Role of Psychological Factors

(1) Background: Halitosis is a frequent condition that affects a large part of the population. It is considered a "social stigma", as it can determine a number of psychological and relationship consequences that affect people's lives. The purpose of this review is to examine the role of psychological factors in the condition of self-perceived halitosis in adolescent subjects and adulthood. (2) Type of studies reviewed: We conducted, by the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) guidelines, systematic research of the literature on PubMed and Scholar. The key terms used were halitosis, halitosis self-perception, psychological factors, breath odor and two terms related to socio-relational consequences ("Halitosis and Social Relationship" OR "Social Issue of Halitosis"). Initial research identified 3008 articles. As a result of the inclusion and exclusion criteria, the number of publications was reduced to 38. (3) Results: According to the literature examined, halitosis is a condition that is rarely self-perceived. In general, women have a greater ability to recognize it than men. Several factors can affect the perception of the dental condition, such as socioeconomic status, emotional state and body image. (4) Conclusion and practical implication: Self-perceived halitosis could have a significant impact on the patient's quality of life. Among the most frequent consequences are found anxiety, reduced levels of self-esteem, misinterpretation of other people's attitudes and embarrassment and relational discomfort that often result in social isolation.

Targeted Chemometrics Investigations of Source-, Age- and Gender-Dependencies of Oral Cavity Malodorous Volatile Sulphur Compounds

Halitosis is a highly distressing, socially unaesthetic condition, with a very high incidence amongst the adult population. It predominantly arises from excessive oral cavity volatile sulphur compound (VSC) concentrations, which have either oral or extra-oral etiologies (90–95% and 5–10% of cases, respectively). However, reports concerning age- and gender-related influences on the patterns and concentrations of these malodorous agents remain sparse; therefore, this study’s first objective was to explore the significance and impact of these potential predictor variables on the oral cavity levels of these malodorants. Moreover, because non-oral etiologies for halitosis may represent avatars of serious extra-oral diseases, the second objective was to distinguish between etiology- (source-) dependent patterns of oral cavity VSCs. Oral cavity VSC determinations were performed on 116 healthy human participants using a non-stationary gas chromatographic facility, and following a 4 h period of abstention from all non-respiratory oral activities. Participants were grouped according to ages or age bands, and gender. Statistical analyses of VSC level data acquired featured both univariate/correlation and multivariate (MV) approaches. Factorial analysis-of-variance and MV analyses revealed that the levels of all VSCs monitored were independent of both age and gender. Principal component analysis (PCA) and a range of further MV analysis techniques, together with an agglomerative hierarchal clustering strategy, demonstrated that VSC predictor variables were partitioned into two components, the first arising from orally-sourced H2S and CH3SH, the second from extra-orally-sourced (CH3)2S alone (about 55% and 30% of total variance respectively). In conclusion, oral cavity VSC concentrations appear not to be significantly influenced by age and gender. Furthermore, (CH3)2S may serve as a valuable biomarker for selected extra-oral conditions.

Colorimetric Dye-Loaded Nanofiber Yarn: Eye-Readable and Weavable Gas Sensing Platform

The colorimetric gas sensor offers an opportunity for the simple and rapid detection of toxic gaseous substances based on visually discernible changes in the color of the sensing material. In particular, the accurate detection of trace amounts of certain biomarkers in a patient's breath provides substantial clues regarding specific diseases, for example, hydrogen sulfide (H₂S) for halitosis and ammonia (NH₃) for kidney disorder. However, conventional colorimetric sensors often lack the sensitivity, selectivity, detection limit, and mass-productivity, impeding their commercialization. Herein, we report an inexpensive route for the meter-scale synthesis of a colorimetric sensor based on a composite nanofiber yarn that is chemically functionalized with an ionic liquid as an effective H₂S adsorbent and lead acetate as a colorimetric dye. As an eye-readable and weavable sensing platform, the single-strand yarn exhibits enhanced sensitivity supported by its high surface area and well-developed porosity to detect the breath biomarker (1 ppm of H₂S). Alternatively, the yarn loaded with lead iodide dyes could reversibly detect NH₃ gas molecules in the ppm-level, demonstrating the facile extensibility. Finally, we demonstrated that the freestanding yarns could be sewn into patterned textiles for the fabrication of a wearable toxic gas alarm system with a visual output.

Small, but smelly: the importance of Solobacterium moorei in halitosis and other human infections

Solobacterium moorei (S. moorei) has been described as Gram-positive, non spore forming, obligate anaerobic bacillus from human feces. The traditional culture and identification of these strains is very difficult (as the strains are often not cultivable or they grow only relatively slowly, in addition to producing only a very few positive biochemical reactions in commercially available identification kits); thus, reliable identification may only be carried out using methods, such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and DNA sequencing. Regarding its pathogenic role, the relevance of S. moorei in halitosis (oral malodor) has a good standing, as it has been suggested by multiple studies, while the isolation of these bacteria from invasive infections is very rare; there are only a few reports available in the literature, regarding infections outside the oral cavity. Based on these reports, affected patients are predominantly characterized compromised immunity and are frequently associated with a dental focus of infection. The aim of our present review is to summarize the currently available knowledge on the pathogenic role of S. moorei in halitosis and other infections and to emphasize the relevance of this neglected anaerobic pathogen.

The Role of Oral Microbiota in Intra-Oral Halitosis

Halitosis is a common ailment concerning 15% to 60% of the human population. Halitosis can be divided into extra-oral halitosis (EOH) and intra-oral halitosis (IOH). The IOH is formed by volatile compounds, which are produced mainly by anaerobic bacteria. To these odorous substances belong volatile sulfur compounds (VSCs), aromatic compounds, amines, short-chain fatty or organic acids, alcohols, aliphatic compounds, aldehydes, and ketones. The most important VSCs are hydrogen sulfide, dimethyl sulfide, dimethyl disulfide, and methyl mercaptan. VSCs can be toxic for human cells even at low concentrations. The oral bacteria most related to halitosis are Actinomyces spp., Bacteroides spp., Dialister spp., Eubacterium spp., Fusobacterium spp., Leptotrichia spp., Peptostreptococcus spp., Porphyromonas spp., Prevotella spp., Selenomonas spp., Solobacterium spp., Tannerella forsythia, and Veillonella spp. Most bacteria that cause halitosis are responsible for periodontitis, but they can also affect the development of oral and digestive tract cancers. Malodorous agents responsible for carcinogenesis are hydrogen sulfide and acetaldehyde.

The Underestimated Problem of Intra-Oral Halitosis in Dental Practice: An Expert Consensus Review

Approximately 90% of halitosis cases originate within the oral cavity (intra-oral halitosis). With a focus on intra-oral halitosis, this narrative review article provides a current summary of the epidemiology, diagnosis and management of halitosis and discusses practical considerations for healthcare professionals (HCPs), including dentists, dental hygienists, general practitioners, community pharmacists, nurses and medical specialists. MEDLINE and PubMed were searched up to 31 December 2019. Additional information was sourced from reference lists of relevant published literature. Full-text articles which reported on the epidemiology, diagnosis and management of halitosis were considered for inclusion. Halitosis affects substantial numbers of individuals globally and is an underestimated problem in dental practice. Current estimates of the prevalence of halitosis, in addition to diagnostic methods and management considerations for halitosis, are discussed. Although not a life-threatening condition, halitosis has a significant impact on patients’ quality of life and can result in psychological consequences including social, professional and affective limitations. Using a simple step-wise approach for diagnosis and treatment, dentists and dental hygienists are ideally placed to respond to an initial consultation for halitosis.

The Effect of Streptococcus salivarius K12 on Halitosis: a Double-Blind, Randomized, Placebo-Controlled Trial

This study was to evaluate the effect of Streptococcus salivarius K12 on tongue coating-associated halitosis. Twenty-eight subjects having tongue coating-associated halitosis were randomly divided into either a test or control group. For each of the 30 days, the test subjects sucked S. salivarius K12 tablet while the control subjects sucked placebo tablets. All the subjects did not take physical (tongue scraping) and chemical (antiseptic mouth-rinse) oral cavity pretreatment prior to use of the tablets. At baseline, and on the 1st, 7th, and 14th day after completing the course of tablets, the subjects were assessed for their organoleptic test (OLT) scores, volatile sulfur compound (VSC) levels, and tongue coating scores (TCS). During the course, all subjects kept their routine oral care habits without scraping their tongue coating. Plaque index, probing depth, and bleeding index were recorded at baseline and at the completion of the trial. On the 1st day following the end of tablet use, the OLT scores and VSC levels had significantly decreased in the test group when compared with the baseline values (P = 0.001 and P = 0.012). The TCS in the test group were also significantly decreased (P = 0.05). At days 7 and 14, the OLT scores in the test group were still significantly lower than the baseline levels (P = 0.006 and P = 0.039 respectively). However, there were no statistical differences with OLT, VSC, and TCS between the test group and the placebo group by analysis of multi-level regression model. The use of S. salivarius K12 did not have significant effect on halitosis with tongue coating cause when the tongue coating was not physically or chemically pre-treated, which implies removing tongue coating is required before Streptococcus salivarius K12 use.

Self-reported halitosis in a sample of Brazilians: Prevalence, associated risk predictors and accuracy estimates with clinical diagnosis

AIMS

To evaluate the prevalence of self-reported halitosis and its predictors, and to determine the accuracy estimates of self-reported measures with clinical evaluation of halitosis.

MATERIALS AND METHODS

This cross-sectional study comprised 5,420 individuals (teaching staff, administrative personnel and ongoing students from Federal University of Minas Gerais), who answered a structured questionnaire containing sociodemographic, medical and dental data, and self-reported halitosis measures. A subsample (n = 159) underwent halitosis assessment through the organoleptic method. Predictors for self-reported halitosis were determined through univariate and multivariate analyses. Accuracy estimates of self-reported measures were evaluated in this subsample.

RESULTS

Prevalence of self-reported halitosis varied from approximately 4%-35%, depending on the self-reported measure. Self-reported halitosis was mainly associated with socio-economic variables (age, gender, educational level), parameters of oral health (gingival bleeding, gingival infections, tongue coating, general oral health evaluation) and impacts on daily activities (family/social environment and intimate relations). Specificity values for self-reported halitosis measures were determined to be high for clinical (organoleptic score ≥2) and strong (organoleptic score ≥4) halitosis. Combinations of self-reported measures retrieved useful accuracy estimates for strong halitosis.

CONCLUSION

Prevalence rates of self-reported halitosis may be considered moderate. Accuracy diagnostic estimates were determined to be useful, with good prediction for non-diseased individuals.

Combining culture and culture-independent methods reveals new microbial composition of halitosis patients' tongue biofilm

Background

Oral malodor is a very discomforting condition deriving from the presence of volatile sulfur compounds in the expired air. In halitosis of intraoral etiology, the volatile sulfur compounds are metabolic products of the oral microorganisms within the biofilm coating the tongue dorsum as well as other tissues in the oral cavity. The aim of this study was to characterize and compare the microbial composition of tongue biofilm in volunteers suffering from halitosis and healthy volunteers by means of both the culture method and culture‐independent cloning technique.

Results

A high bacterial variety (more than 80 different species) was detected using the combination of both methods. A distinct bacterial composition was revealed in the halitosis‐associated biofilms compared with the health‐associated biofilms. Actinomyces graevenitzii was shown to be significantly associated with the halitosis condition. The culture method identified 47 species, included Veillonella rogosae, never isolated from the tongue biofilm of halitosis patients so far. In the healthy condition, the culture‐dependent method showed that the most frequent species were Streptococcus parasanguinis among the aerobes and Veillonella spp. among the anaerobes. The culture‐independent cloning method detected more than 50 species. Streptococci, in particular S. mitis/oralis, S. pseudopneumoniae, and S. infantis as well as Prevotella spp., were found most frequently in halitosis patients. Streptococcus salivarius and Rothia mucilaginosa were found more frequently in the healthy condition.

Conclusions

The combination of the culture‐dependent and culture‐independent cloning techniques allowed for a widespread analysis of the tongue biofilm in halitosis patients. The results can support further pharmacological research for new antimicrobial agents and halitosis therapy strategies.

Otorhinolaryngological symptoms among smokeless tobacco (Maras powder) users

OBJECTIVE:

This study aims to investigate the relationship between smokeless tobacco (maras powder) consumption and otorhinolaryngological symptoms.

METHODS:

This descriptive study was carried out on 599 participants. The participants were divided into two groups. Of these, 299 (49.9%) patients aged over 18 years were the first group; they used smokeless tobacco for at least 5 years. The remaining patients comprised the second group, which included 300 (50.1%) healthy volunteers who did not use tobacco or its products and demonstrated some similarities with the first group. For the purpose of data collection, a questionnaire consisting of 45 questions was administered to the participants.

RESULTS:

Cough, sputum, shortness of breath, dysphagia, snoring, and apnea-hypopnea were found to be significantly increased in smokeless tobacco users. The highest odds ratio (OR) found was for sputum at 2.615. Similarly, other oral cavity symptoms such as mouth tickling, dryness of throat, mouth sores, halitosis, taste disorders, and toothache were found to be significantly increased in smokeless tobacco users. It is noteworthy that halitosis was 9.4 times more prevalent among smokeless tobacco users than in the non-tobacco users. Sinonasal symptoms such as sneezing, headache, facial fullness, and anorexia were found to be significantly increased in smokeless tobacco users. However, there were no differences between the groups in terms of ear symptoms.

CONCLUSION:

This study demonstrated that the negative effects of smokeless tobacco consumption were particularly higher in the oral cavity, which in turn gave rise to a number of serious upper respiratory tract complaints.

Genuine halitosis in patients with dental and laryngological etiologies of mouth odor: severity and role of oral hygiene behaviors

The aims of the study were to determine the severity of halitosis and the association between oral hygiene practices and the severity of malodor in patients with dental and laryngological etiologies of genuine halitosis. Thirty-five laryngological and 40 dental patients with halitosis completed a structured interview and underwent laryngological and dental examinations. Halitosis was assessed using organoleptic and halimeter tests. Greater halitosis severity in laryngological patients was associated with worse clinical status of the palatine tonsils, less frequent toothbrushing, less frequent use of tongue cleaners, fewer daily meals, and increased use of mouthrinses. Among dental patients, more severe halitosis was associated with worse clinical status of the periodontium, more tongue coating, less saliva secretion, and less frequent use of dental floss, interdental toothbrushes, and tongue cleaners. Oral hygiene was found to be a key moderator of the relationship between status of the periodontium or tonsils and severity of halitosis. The severity of halitosis in laryngological patients and dental patients is essentially similar; however, oral hygiene routines are associated with different effects in each group. Consequently, individual recommendations for patients with halitosis should be adjusted for the underlying disease and emphasize the role of effective specific hygiene behaviors.

Effect of Camellia sinensis plant on decreasing the level of halitosis: A systematic review

Tea is the second most consumed beverage. Polyphenolic catechins of green tea have a number of beneficial effects in oral cavity. This study aims to evaluate the clinical effects of green tea on halitosis through a systematic review of available literature. All available randomized, clinical trials - with a relevant subject that met the inclusion criteria - were included by searching PubMed, Cochrane, ProQuest, and Google Scholar, and Scopus databases. To score the selected articles, 27 items of CONSORT 2010 checklist were considered. Each article was reviewed by all the authors. Searching the PubMed database yielded 42 articles, 2 of which met the inclusion criteria. None of the 12 articles were obtained through Cochrane library, and 85 articles retrieved from ProQuest database met the inclusion criteria. Three hundred and five articles were obtained from Google Scholar, three of which fulfilled the inclusion criteria. Two articles were omitted because they were duplicated, and the rest were excluded. Searching the Scopus database yielded 270 articles, 2 of which met the inclusion criteria, but they were also duplicated. Finally, two studies were selected according to the inclusion criteria of the study. In both of the included articles, the early effect of green tea use was statistically significant in comparison with baseline. One of the studies showed the long-term effect of green tea mouthwash. Green tea can reduce halitosis through rinsing and antimicrobial effect.

Self-perception, knowledge, and awareness of halitosis among female university students

Background

Halitosis or oral malodor is defined as an unpleasant breath odor. It can become a serious problem affecting individuals’ social communication and self-confidence. Furthermore, it is a discomforting issue for the people around the person affected, because they consider it embarrassing to inform the person of the problem.

Aim

This study was designed to measure self-perception, knowledge, and awareness of halitosis among female university students in Saudi Arabia.

Materials and methods

A cross-sectional survey was implemented with 392 volunteer participants who responded to a questionnaire on their self-perception, knowledge, and awareness of halitosis.

Results

The response rate was 89.1% (392/440). Self-perception of halitosis was low (21.4%), whereas a larger percentage (78.1%) indicated noticing people with bad breath. Most participants (80.4%) thought that the gastrointestinal tract is the primary source of halitosis. Seventy-seven percent preferred using personal methods such as mouthwash and chewing gum to treat oral malodor. According to 82.1% of respondents, a dentist is the most appropriate professional to treat halitosis.

Conclusion

The investigation revealed low self-perception and limited knowledge regarding halitosis. Therefore, the role of dentists in informing and educating their patients concerning oral malodor should be enhanced. Public education about the causes of and possible ways of managing bad breath should be increased.

Comparison of oral malodors before and after nonsurgical periodontal therapy in chronic periodontitis patients

Background/purpose

Periodontal diseases have been considered as a source of oral malodor or halitosis. Improvement of oral malodor in chronic periodontitis patients has recently been observed after nonsurgical periodontal therapy in combination with tongue cleaning and/or chlorhexidine mouth rinsing. The present study, however, evaluated the impact of nonsurgical periodontal therapy alone on the oral malodor in chronic periodontitis patients by comparing the intraoral concentrations of volatile sulfur compounds (VSCs) before and after nonsurgical therapy.

Materials and methods

Using a sulfide monitor, the total VSCs in exhaled breath were measured in 80 patients with chronic periodontitis prior to and 1 month after nonsurgical periodontal therapy (re-evaluation phase). Malodor was defined as a VSC score > 75 parts per billion (ppb) and > 110 ppb, respectively.

Results

Significantly lower level of VSCs was recorded at periodontal re-evaluation (55 ± 9.7 ppb) than before treatment (89 ± 16.3 ppb). Before treatment, 27 (34%) patients were considered to have malodor, defined as VSCs > 75 ppb. After treatment, 16 patients (20%) had VSC scores > 75 ppb, including 10 of 27 patients with baseline VSC scores > 75 ppb and six of 53 patients with baseline scores ≤ 75 ppb. The risk of malodor differed significantly before and after treatment (P = 0.035, McNemar's test). However, when malodor was defined as VSCs > 110 ppb, the difference in risk showed only borderline significance (P = 0.077).

Conclusion

On the basis of our findings, we suggest that nonsurgical periodontal therapy has a mild impact on oral malodor.

Recombinant Sox Enzymes from Paracoccus pantotrophus Degrade Hydrogen Sulfide, a Major Component of Oral Malodor

Hydrogen sulfide (H₂S) is emitted from industrial activities, and several chemotrophs possessing Sox enzymes are used for its removal. Oral malodor is a common issue in the dental field and major malodorous components are volatile sulfur compounds (VSCs), including H₂S and methyl mercaptan. Paracoccus pantotrophus is an aerobic, neutrophilic facultatively autotrophic bacterium that possesses sulfur-oxidizing (Sox) enzymes in order to use sulfur compounds as an energy source. In the present study, we cloned the Sox enzymes of P. pantotrophus GB17 and evaluated their VSC-degrading activities for the prevention of oral malodor. Six genes, soxX, soxY, soxZ, soxA, soxB, and soxCD, were amplified from P. pantotrophus GB17. Each fragment was cloned into a vector for the expression of 6×His-tagged fusion proteins in Escherichia coli. Recombinant Sox (rSox) proteins were purified from whole-cell extracts of E. coli using nickel affinity chromatography. The enzyme mixture was investigated for the degradation of VSCs using gas chromatography. Each of the rSox enzymes was purified to apparent homogeneity, as confirmed by SDS-PAGE. The rSox enzyme mixture degraded H₂S in dose- and time-dependent manners. All rSox enzymes were necessary for degrading H₂S. The H₂S-degrading activities of rSox enzymes were stable at 25–80°C, and the optimum pH was 7.0. The amount of H₂S produced by periodontopathic bacteria or oral bacteria collected from human subjects decreased after an incubation with rSox enzymes. These results suggest that the combination of rSox enzymes from P. pantotrophus GB17 is useful for the prevention of oral malodor.

Self-perceived halitosis and related factors among adults residing in Riyadh, Saudi Arabia. A cross sectional study

Objectives

This cross-sectional observational study was conducted to determine the prevalence of self-perceived halitosis among adults in Riyadh, Saudi Arabia and to assess the relation of halitosis with some socio-demographic factors, oral habits and health practices.

Materials and methods

A questionnaire was distributed to randomly selected subjects including senior high school students, college students and employees working in governmental offices. High schools and governmental offices were selected using systematic random sampling from each of the main five regions of Riyadh. The college students were selected from the major universities in Riyadh. One hundred questionnaires were randomly distributed in each of the 15 locations for males and 15 for females (5 schools, 5 universities and 5 governmental offices for each gender) giving a total of 3000 questionnaires.

Results

The prevalence of self-perceived halitosis was 22.8% among the participants. The majority of the subjects with self-perceived halitosis experienced bad breath on waking up (83.5%). Nearly half of the sample with self-perceived halitosis was told by others that they had bad breath, 25.8% visited a doctor regarding that, 23.8% received treatment for their bad breath and 54.1% made trials to control their problem by using some aids. Self-perceived halitosis was found to be more prevalent among males compared to females (P < 0.000), whereas, no statistically significant differences were found among the different age groups (P = 0.317). A statistically significant relationship was found between self-perceived halitosis and times of mouth cleaning, use of tooth brush, use of tooth paste, tongue cleaning (P < 0.000), and the use of dental floss (P = 0.004). A statistically significant relationship was also found between self-perceived halitosis and shisha (P < 0.000) and cigarette smoking (P = 0.045).

Conclusion

The prevalence of self-perceived halitosis among the population in Riyadh is within the range reported in other countries. Self-perceived halitosis is related to gender, inadequate oral hygiene practices and cigarettes and shisha smoking however, it is not related to age.