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Acta Odontológica Latinoamericana

versão On-line ISSN 1852-4834

Acta odontol. latinoam. vol.29 no.2 Buenos Aires set. 2016



Prevalence of self-reported halitosis and associated factors in adolescents from southern Brazil


Montalverne H. B. Lopes1, Cassiano K. Rösing2, Paulo Roberto G. Colussi1, 2, Francisco Wilker M. G. Muniz2, Maria S. S. Linden1

1 School of Dentistry, University of Passo Fundo, Brazil
2 School of Dentistry, Federal University of Rio Grande do Sul, Brazil

CORRESPONDENCE Dr Cassiano Rosing Ramiro Barcelos, 2492. 90035003 Porto Alegre – RS – Brazil.


The aim of this study was to assess the prevalence of selfreported halitosis and associated factors in adolescents from Passo Fundo, Brazil. Additionally, we studied adolescents’ concern with their own breath and whether anyone had ever told them that they had halitosis. A crosssectional observational survey was conducted on 15to 19 year old high school students from public and private schools in the city of Passo Fundo, Brazil. The random sample consisted of 736 adolescents from 20 schools. An interview with a structured questionnaire was administered. The prevalence of selfreported halitosis and associated factors was analyzed by either the chisquare test or Fisher’s exact test. The prevalence of selfreported halitosis was 39.67%. The mother’s level of education was associated with the outcome. Gender and behavioral habits were not associated with selfreported halitosis. Halitosis reported by others presented a prevalence of 10.73% and was associated to male gender and oral hygiene habits. Individuals with less toothbrushing frequency and no use of dental floss were associated to halitosis reported by others. It was observed that 88.58% of the participants are concerned with halitosis. It is concluded that there is high prevalence of selfreported halitosis, which is associated with a socioeconomic pattern. Most adolescents report concern with their own breath.

Key words: Halitosis; Adolescent; Prevalence; Associated factors.


Prevalência de halitose autorreportada e fatores associados em adolescentes do sul do Brasil

O objetivo do presente estudo foi verificar a prevalência de halitose autorreportada e fatores associados em adolescentes de Passo Fundo, Brasil. Além disso, foram verificados a preocupação dos adolescentes com o seu próprio hálito e se eles já foram avisados por alguém sobre essa condição em qualquer momento de suas vidas. Esse estudo transversal envolveu estudantes do ensino médio, da rede pública e privada, com idades entre 15 e 19 anos, da cidade de Passo Fundo, Brasil. Uma amostra randômica de 736 adolescentes de 20 escolas foi utilizada. Um questionário estruturado foi aplicado. A prevalência de halitose autorreportada e fatores associados foram analisados por quiquadrado ou teste exato de Fischer. A prevalência de halitose autorreportada foi de 39,67%. O nível educacional da mãe foi associado com esse desfecho. Gênero e hábitos comportamentais não estiveram associados com halitose autorreportada. Apenas 10,37% dos adolescentes reportadam que outras pessoas indicaram a existência desse problema, sendo associada com o gênero masculino e com hábitos de higiene bucal. Os indivíduos que reportaram menor frequência de escovação dentária e ausência do uso de fio dental apresentaram associações com a advertência da halitose por outras pessoas. Foi observado que 88,58% dos participantes são preocupados com o próprio hálito. Concluiuse que a halitose autorreportada apresenta alta prevalência e está associada com fatores socioeconômicos. Advertência sobre mau hálito por outras pessoas foi relatada apenas por uma minoria, sendo associado com o gênero masculino e hábitos de higiene bucal. A maioria dos adolescentes reportou preocuparse com o próprio hálito.

Palavras chave: Halitose; Adolescente; Prevalência; Fatores associados.



Halitosis is a condition in which exhaled air is unpleasantly altered both for patients and for people with whom they relate1. It affects millions of people around the world, although its prevalence varies, apparently triggered mainly by lack of oral hygiene and a disorderly lifestyle. It can cause social restrictions, interfere in quality of life, and may be an indicator of important systemic diseases. In most societies where halitosis is prevalent, people seek solutions, usually due to the discomfort or embarrassment to which they are subjected2. A lot of money is spent – often unsuccessfully – on breath fresheners1.
One of the reasons for studying halitosis is its social impact as a result of patients feeling insecure in social, professional and family interactions. It may also influence quality of life and embarrass people relating to the individual with bad breath. Therapeutic interventions in the health field are basically assessed through two types of outcomes. Surrogate outcomes are defined as a measurement of the disease process, and are usually therapycentered, whereas true outcomes reflect unequivocal evidence of tangible benefit to patients, and are exclusively patientcentered. Surrogate outcomes are used assuming they represent true outcomes, either separately or together3. For example, some studies assess halitosis only through the objective measurement of volatile sulfur compound (VSC) concentrations in the exhaled air. The results of these investigations have a completely different meaning from studies that determine the percentage of individuals who report having halitosis1. Both outcomes are meaningful to understanding the issue, but observation through VSC monitors is considered a surrogate outcome, while selfreported perception of halitosis is recognized as a true outcome. Epidemiological observation taking into consideration both types of outcomes provides important information and enables broader understanding of the issue1.
Adolescence is the transition period between childhood and adulthood, and is characterized by various changes in biological, psychological and social development4. Adolescents are subject to several healthrelated manifestations, including halitosis, which exceeds the biological scope, affecting the social scope and potentially harming the physical and psychological health of affected individuals5. Moreover, presence of halitosis may indicate presence of important systemic diseases requiring urgent diagnosis and treatment.
Nevertheless, in Brazil there are few scientific papers on adolescents, and still fewer on adolescent halitosis, which is a highly overestimated and taboo subject. The aim of this study was to assess prevalence of selfreported halitosis and associated factors in adolescents from southern Brazil. Additionally, it assessed subjects’ concern with their own breath and whether they had ever been told they had bad breath.


Study design and location
In this crosssectional observational study, we interviewed 15 to 19 yearold adolescents enrolled at public and private high schools in the city of Passo Fundo, in 2012. Passo Fundo is located in the state of Rio Grande do Sul, southern Brazil. The city’s population is about 190,000, according to the Brazilian Institute of Geography and Statistics. More than 95% of the population lives in the urban area with a poverty incidence of 27.91%, and a Gini Index of 0.41. In 2012, the city reported 7,558 students enrolled in regular high school education at 23 schools, divided into 16 public schools and 7 private schools, all in the urban area of the city. Of this total 6,256 students (82.78%) attended public schools and 1,302 (17.22%) attended private schools (Department of Education of the State of Rio Grande do Sul).

Ethical considerations
The Institutional Review Board of the University of Passo Fundo approved this study following authorization from the 7th Regional Office of Education to conduct it at public schools, and after formal approval by the principals of the private schools. All selected students presented the Informed Consent Form signed by parents or legal guardians, and those who were present on the day of the survey were interviewed. If a student was absent on the day of the survey, a second attempt was made to collect data. This study was fully conducted in accordance with the World Medical Association Declaration of Helsinki.

All 23 high schools in the city were visited by the study coordinator and invited to participate. Twenty schools accepted the invitation (n=20), and 30% of the students from each of them were invited to participate. Participants were selected randomly by draw from the lists of all students aged 15 to 19 years from each participating school, regardless of their school schedule. The research team visited all classrooms that included selected students, to present the objectives of the study. After the explanation, the selected students received an Informed Consent Form to be signed by their parents or guardians. In case of absence, a later contact was made.

A structured questionnaire including demographic data, socioeconomic condition, general health beha vior, health record, and oral health selfperception was administered using a set of questions from the PCAToolSB Brazil adult version, validated in Brazil6, in addition to other questions on oral health at this age, such as oral hygiene habits and halitosis. The adolescents were interviewed between April and July 2012 by teams that included an interviewer and a recorder who had been previously trained by the study coordinator to ensure standard procedures. The training consisted of theoretical classes that included literature review on the subject, and reading and explanation of each question in the questionnaire. First, team members were trained, and secondly, high school students not selected to participate in the study were examined. The reproducibility of the interview was verified in 10% of the respondents chosen by draw, revealing an agreement rate of 98%.

Statistical analysis
The dependent variable was the prevalence of selfreported halitosis, which was ascertained by asking three questions: “Do you have bad breath?”, “Has anyone ever complained to you about your breath?” and “Are you concerned about your breath?”. The questions were answered on a Lickert scale response card with the answer choices “never”, “rarely”, “sometimes”, “often”, and “always”7. The answers were classified as “YES” for “some times”, “often”, and “always”; and as “NO” for “never” and “rarely”. The explanatory variables for halitosis in adolescents were divided into two groups (Fig. 1) one group with sociodemographic factors, and another with behavioral, biological, and oral factors8.

Fig. 1
: The theoretical framework linked to the analysis of the present study.

Ethnicity/skin color was classified as white or nonwhite. The nonwhite group included adolescents who referred to themselves as black, yellow, brown or indigenous. Socioeconomic condition was assessed through two factors. The first was mother’s level of education, classified into three groups: (1) complete or incomplete higher education, (2) complete or incomplete high school, and (3) complete elemen tary school at the most. The second factor was the type of school the adolescent attended, using public or private school as an income proxy, with students from public schools being considered to belong to lower income families. Smoking was classified into three groups: (1) no history of smoking, (2) current smokers and (3) former smokers. Health condition was classified into two groups: (1) no health problem or unaware of health problem and (2) with a health problem that has lasted or will probably last more than one year. Toothbrushing frequency was classified into three groups: (1) more than three times a day, (2) three times a day, and (3) less than three times a day. Use of dental floss and orthodontic treatment were both dichotomized as yes or no.
Data were analyzed with the statistical package SPSS 18 (SPSS Inc., Chicago, United States). Associations between the dependent variable and independent variables were analyzed by chisquare test or Fisher’s exact test, and presented by frequency distribution. The significance level applied was 5%.


This study addressed 20 schools in the city of Passo Fundo. Participant recruitment is illustrated in the flowchart in Fig. 2.

Fig. 2
: Study flowchart.

Results show that 15 to 19yearold old students in the city of Passo Fundo are predominantly female. Most individuals in this sample are 15, 16 and 17 years old. Regarding sociodemographic characte ristics, most individuals are white, study at public schools, and the mother’s level of education is low. In relation to health habits, a small percentage of individuals (less than 6%) reported having smoked at some time, more than 85% brush their teeth at least 3 times a day, and about half report using dental floss. About 12% report having health problems (mostly respiratory conditions), and about one third are under orthodontic treatment (Table 1).

Table 1. Description of the study sample.

Prevalence of selfreported halitosis was 39.67%. Table 2 shows the selfreported halitosis outcome and its association to potentially explanatory exposures. Gender had no statistically significant association to the outcome, although the result was close to reaching significance. Similarly, ethnicity and type of school were not associated to selfreported halitosis. The mother’s level of education was associated to the outcome, considering that students whose mothers had less access to formal education presented higher prevalence of selfreported halitosis. Smoking, oral hygiene, health conditions and history of orthodontic treatment were not associated to selfreported halitosis.

Table 2. Frequency distribution of exposures regarding self-reported halitosis among adolescents 15 to 19 years old.

Table 3 shows the results for “halitosis indicated by others”. For this type of assessment, prevalence of halitosis was 10.73%. Halitosis indicated by others was associated to male gender and oral hygiene habits. Individuals with less toothbrushing frequency and no use of dental floss were associated to indication of halitosis by others. Concern with bad breath was assessed, showing that 88.58% of participants care about halitosis, but no statistically significant association with the explanatory variables was found. Nonwhite ethnicity presented a lower percentage of concern, almost reaching statistical significance (Table 4).

Table 3. Frequency distribution of exposures regarding halitosis indicated by others among adolescents 15 to 19 years old.

Table 4. Frequency distribution of exposures regarding concern with bad breath among adolescents 15 to 19 years old.


The aims of this study were to determine prevalence of selfreported halitosis and associated factors in adolescents from Passo Fundo, Brazil and to measure adolescents’ concern with their own breath and whether they had ever been told they had bad breath. A crosssectional observational study was carried out on high school students aged 15 to 19 years. The sample was similar to the percentage of students enrolled at public and private schools in the city and the percentage of explanatory variables obtained such as ethnicity and gender was similar to the city’s population data (Fig. 2). All 23 high schools in the city were invited to participate, of which 20 accepted. A simple random sample of adolescents was selected, with a total 30% of students from each school. Of the selected students, 40.08% accepted to participate. Other studies using similar methodology report higher9 or similar10 participation rates. Although according to their age group, participants were close to being independent from their parents, the fact that legal restrictions required parents’ signature on the consent form may account for the response rate. Efforts were made to decrease any biases in the study, especially concerning the questionnaire. For this purpose, the research team was trained so that members would act similarly and to reduce any doubts that might arise while administering the questionnaire. Question comprehension was previously assessed among groups of adolescents.
Selfassessment or selfperception of halitosis is a highly relevant outcome, since it involves the individual in the process and makes him/her understand the importance of the condition11. Accordingly, it is safe to assume selfperception as a true patientcentered outcome, which is highly recommended in contemporary research in the health field3. However, organoleptic testing and selfperception both involve a subjective component, which may ultimately be questioned; therefore the additional use of an objective measurement to assess breath, such as the volatile sulfur compounds monitor (halimeter), may be recommendable. Its main limitation is that it does not detect all of the odorivectors present in exhaled air, and indicates only quantitative – not qualitative – values. It only detects some of the components offensive to the human sense of smell, while selfassessment relates to the individual perception of the person affected by halitosis1,12.
Studies that assess halitosis exclusively through objective measurement of volatile compound concentration in exhaled air provide results which have a completely different meaning from those of studies that verify the percentage of individuals who report having halitosis1,11. Both study methods make important contributions to understanding the issue, but observation using VSC monitors is considered a surrogate endpoint, while selfperceived halitosis is recognized as a true outcome. Epidemiological studies with true outcomes provide insight into the real impacts of halitosis. The perception and impact of oral health status on quality of life have only recently become a matter of concern to the academic community, and several authors currently endorse patientbased results. In addition to gathering substantial information, studies aim to measure the impact of oral health disorders on the patient’s quality of life1,12. This standpoint is important with relation to the concept of health not only as the absence of disease, but also as quality of life, and the concept of healthcare as not merely extending life and eliminating diseases, but rather, doing so while maintaining the best possible quality13. This study showed high prevalence of selfreported halitosis (39.7%), regardless of gender. This agrees with other studies on halitosis conducted with similar methodology on adults. In the United States, (1996) prevalence of selfreported halitosis was 31%14; in France (1998) it was 32% among 4815 individuals aged 15 years or older15; in Switzerland (2009) it was 32% among 419 adults aged 18 to 94 years16. Another Swiss study (2009) on 626 army recruits aged 18 to 25 years found 21.4% prevalence of selfreported halitosis17. In Japan (2010) a similar study on 474 university students found 42% prevalence of selfreported halitosis18. Our study found similar results in Brazil, revealing halitosis as a condition having high impact. Our study found a statistically significant association between selfreported halitosis and having a mother with a lower level of education, with 19.1% of the respondents having mothers whose educational level was not higher than elementary school and reporting halitosis.
The same has been reported in studies showing that socioeconomic conditions, such as mother’s level of education, are strongly associated to poorer oral health conditions19,20. Adolescents with poorer oral health conditions, including higher prevalence of cavities and periodontal diseases can be expected to have higher prevalence of bad breath. Although the difference was not statistically significant, 34.2% of the respondents answered “yes” to selfreported halitosis and attend public schools, while 5.5% answered “yes” and attend private schools. Behavioral, biological, and oral factors are not statistically associated to selfreported halitosis. Fiftynine percent of the respondents brushed their teeth three times a day, which is the most common toothbrushing frequency reported in the literature21,22. This may account for the absence of association observed in this topic. It has also been suggested that the epidemiological situation of oral health in adolescents may not be directly related to the oral hygiene habits reported. With regard to smoking, 37.2% of the students reported halitosis and having never smoked. Surprisingly, no association was found in this study between halitosis and smoking, even though it is known that the smell of cigarette may be mistaken for halitosis and exposure to smoking causes deterioration in oral health conditions, especially periodontally, which is related to halitosis. Another important finding is that 34% of this sample reports suffering from halitosis with no presence of systemic diseases. This supports other studies that showed halitosis mainly as a condition with oral etiology23. Subjects with poorer oral health status and behaviors could be expected to be more likely to have halitosis, as would those under orthodontic treatment as a result of the difficulty in performing oral hygiene. However, there was no statistically significant association between these factors in this study. The fact that not much literature is available about halitosis in adolescence makes it difficult to compare data for these topics. A less frequent approach to measuring halitosis is through third party reporting. This method was used in a study on a population of elderly people in the United States, which found prevalence of 24%14. In contrast, our study found that 10.7% of the sample had been told they had bad breath at some time in their lives. This difference may be explained by the age difference or even by cultural differences between populations.
Our study found a statistically significant association between halitosis and toothbrushing frequency, as well as between halitosis and use of dental floss. Of the respondents, 6.5% were male and reported halitosis indicated by others, presenting a statistically significant association. Of the respondents who reported having been told they had bad breath, 4.8% claimed they brushed their teeth three times a day, and 4.2% said they used dental floss. Thus, a relation between supposedly more adequate oral hygiene habits and lower impact of halitosis is clearly seen. The discrepancy between selfreported halitosis and halitosis indicated by others can be accounted for by the fact that the former reflects selfperception while the latter requires someone else to be willing to point out the presence of halitosis. Other studies also reflect this discrepancy14,23.
Our study also investigated whether adolescents are concerned with their own breath, finding that 88.7% are. This concern was independent of gender, ethnicity, type of school, mother’s level of education, toothbrushing frequency, use of dental floss, orthodontic treatment, or other associated factors, without statistically significant association between the level of concern with halitosis and the explanatory variables. People of all ages, including adolescents, have long been concerned about halitosis. This is reflected by the considerable increase in the sale of mouthwashes, as shown by a study conducted in Brazil,24 and massive advertising campaigns for breath fresheners25. Halitosis is a health condition with high prevalence1,2,14,17, which may be present from childhood to old age, thus including adolescence. Halitosis has high social impact, affecting family, social, and professional life, and may have an impact on quality of life. A recent study on adolescents showed that those with selfreported halitosis had lower scores of quality of life measured by the OHIP1426. Halitosis may thus be inferred to have an impact on public health. Despite the importance of halitosis as a highly prevalent condition, there are few studies involving adolescents, and few studies in general, since halitosis has historically been treated as an issue of lesser importance in dentistry1,12,25. The results of this study should be interpreted in light of the methodological understanding of its capacity to generate evidence. Because it is a crosssectional study, causality may not be inferred. However, the observation of associated factors provides information on risk indicators, which are essential for establishing preventive strategies, early diagnosis and prompt treatment. Considering the methodological characteristics and limitations, the results of the present study allow us to conclude that:
- Selfreported halitosis is a prevalent condition in about 40% of adolescents.
- Halitosis reported by others was observed in about 10% of adolescents.
- Almost 90% of adolescents reported concern with their own breath.
- Mother’s low level of education was associated to selfreported halitosis.
- Males were more likely to have halitosis reported by others.
- Toothbrushing frequency and the use of dental floss are potential protective factors.


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