Oral health habits , prevalence of dental caries and dental erosion in adolescents

Objective To assess oral hygiene habits, and prevalence of dental caries and erosion in adolescents of Campina Grande, Paraíba, Brazil. Methods Cross-sectional study with random cluster sampling involving 201 15-year-old schoolchildren. Oral health habits were obtained through questionnaire, and socioeconomic data, by means of interviews. The DMFT index was adopted to determine the prevalence of caries and that proposed by O’Sullivan, to assess dental erosion. Data were analyzed using the Statistical Package for Social Sciences (SPSS) version 18. A 5% significance level was adopted. Results All subjects reported using toothbrush and toothpaste, 50.7% reported dental flossing, and association was found between sex and use of mouthwash (p <0.05). Regarding dental caries, the mean DMFT was 3.67 and 51.7% had DMFT lower than or equal to 3. For dental erosion, 18.4% of the sample had erosive lesions, predominantly enamel lesions (92%). Conclusion The use of dental floss was low and adolescents revealed unsatisfactory index. The DMF-T value was moderate and lower than that reported for the Brazilian age group. The prevalence of dental erosion was high, with predominance of enamel lesions. Indexing terms: Dental caries. Oral hygiene. Tooth erosion.


Conclusion
The use of dental floss was low and adolescents revealed unsatisfactory index.The DMF-T value was moderate and lower than that reported for the Brazilian age group.The prevalence of dental erosion was high, with predominance of enamel lesions.

Oral health habits, prevalence of dental caries and dental erosion in adolescents
Hábitos de higiene oral, prevalência de cárie e erosão dentária em adolescentes

INTRODUCTION
Factors considered extra-biological, such as economic level, behaviors and self-care have been pointed out as being factors that lead to increasing prevalence of oral pathologies in adolescents 1 .Dental caries is among the most frequent oral pathologies in adolescents [2][3] .
The last national oral health survey (SB BRASIL 2010) showed a mean DMF-T of 4.25 in adolescents from 15 to 19 years of age, but in the northeastern regions, this index rises to 4,53, and in João Pessoa, capital of the State of Paraíba, the DMF-T rises to 6.15 2 .These differences demonstrate regional inequalities, so that the representativity of distribution of the disease in geographical macro-regions may underestimate or mask some of the regional or local problems 3 .
At present, there is a variety of instruments that help to control dental biofilm and in turn, to prevent oral diseases through habits in the home, such as toothbrushing and the use of dental floss that play an important role in removing biofilm 1 .
In Brazil, a decline in caries disease was verified in the first decade of the 21st Century 2 .Studies began to be directed towards other areas to monitor the trends in the population related to oral health diseases, among them, the growing prevalence of dental erosion in children and adolescents, with the main consequence of wear on the tooth surface [4][5] .This is of idiopathic origin or is caused by a known source of acid 6 , with individual factors and lifestyle having great relevance in its development 7 .Although studies on the prevalence of tooth erosion have been conducted in Brazil [8][9][10][11] studies involving adolescents in the Brazilian Northeast are still rare 7 .In view of the foregoing, the aim of this study was to evaluate the oral hygiene habits and the prevalence of dental caries and erosion in adolescents.

Ethical aspects
This study was submitted to and approved by the Research Ethics of UEPB (Protocol 03263612.4/0000.5187).

Population and sample
The sample was composed of 201 schoolchildren 15 years of age, of both sexes, regularly enrolled in the day shift at 20 schools of the state public teaching network, localized in the urban zone of the City of Campina Grande, FCM COSTA et al.
family income) and those referring to hygiene habits (use of toothbrush, toothpaste, dental floss, mouthwash and tongue cleaner) were collected by means of a questionnaire.
The dental exam was performed on the school premises, in a reserved room, under standardize artificial lighting 9,14 coupled to the head of the researchers 7 (Petzl Zoom head lamp, Petzl America, Clearfield, UT, USA).The subjects were seated on a chair, and the examiner stood behind or in front of the chair.The examiners wore Individual Protective Equipment -IPEs.
Before the clinical exam, supervised toothbrushing was performed.The dental condition was evaluated by means of the DMF-T index, with the use of an oral mirror No.3 (Trinity, Campo Mourão, PR, Brazil) and WHO probe (Trinity, Campo Mourao, PR, Brazil) 15 .The DMF-T variable was dichotomized into ≤ 3 e >3, in view of the World Health Organization and International Dental Federation (WHO/IDF) goal for the year 2000 16 .
Dental erosion was evaluated according to the index proposed by O'Sullivan 6 adapted for use in the four maxillary incisors 17 and maxillary and mandibular first molars 9,12.The choice of this index was because it included information about the severity, location and area affected by the condition, in addition to being proposed for performing the measurement of dental erosion in children and adolescents.

Data analysis
The findings were saved in a data base with the resources of the Statistical Package for the Social Sciences (SPSS), version 18.0.For data analysis, the descriptive and analytical statistical techniques were used.In the bivariate analyses the Pearson Chi-square and Exact Fisher tests were used.The level of significance considered was 5%.

RESULTS
With respect to the sociodemographic characteristics, the authors verified the predominance of mulatto (55.7%), followed by white (21.9%),Oriental (11.5%) and black (10.9%) persons.Relative to family income, the majority (46.8%) reported an income higher than or equal to two minimum wages 18 , while 42.8% informed a family income lower than two minimum wages.Approximately 10.4% did not know their family income.Relative to sex, predominance of the female sex was verified (62.2%).
All the adolescents reported using a toothbrush and toothpaste; however, only half the sample (50.7%), used dental floss, so that association was verified between the use of oral mouthwash and sex (Table 1).The mean DMF-T found for the sample was 3.67 (± 3.31); median 3.0; minimum 0, and maximum 15.Of the individuals, 22.9% had a DMF-T equal to zero.Approximately half of the schoolchildren (51.7%, n=104) presented a DMF-T equal to or lower than 3.With respect to the DMF-T and occurrence of dental erosion, no statistical significance was found; whereas, in relation to the use of oral hygiene instruments, association was observed between the use of a tongue cleaner and the DMF-T (Tables 2 and 3).
Relative do dental erosion, 18.4% (37) of the adolescents presented some lesions (Table 3).As regards the characteristics of the erosive lesions, the majority were characterized by the satin-like of the enamel, presenting no loss of contour (69.7%), localized on the vestibular surface (58.9%) and with less than half of the surface affected (59.9%).The authors observed a clear prevalence of lesions restricted to tooth enamel (92%) (Table 4).

DISCUSSION
The moderate to high prevalence of dental caries continues to be a reality worldwide 19 .The frequency of brushing; use of dental and regular visits to the dentists are important determinants of oral health 18 .
Relative to the socioeconomic characteristics referring to race, the majority of the participants declared they were mulattos; this could be explained since the majority of the Northeastern population affirm being mulatto 20 .According to Carvalho 21 , the increase in the number of those declaring they were mulatto in the Brazilian census is justified by the "migration" of white and black people to the category mulatto, and not by the occurrence of the racial miscegenation process.
In this study, the majority of the adolescents reported an income equal to or higher than two minimum wages.The female sex accounted for the majority of the sample.However, the oral hygiene habits reported were better in the male sex, corroborating the findings of a previous study.According to Calderon and Mallory 22 , the socioeconomic and behavioral factors have an influence on the development of poor oral hygiene habits, and this in turn influences the development and both the prevalence and incidence of dental caries disease.
Control of dental biofilm involves different mechanisms, such as the use of dental floss, toothbrushing and use of oral mouthwashes, among others 23 .All the adolescents reported that they brushed their teeth at least once a day, and half of the sample mentioned the use of dental floss.The use of these means by schoolchildren could be a regular means of removing biofilm, helping to contain carious and periodontal infections, seeing that they are directly related to deficient oral hygiene 2 .There was a low level of use of the tongue cleaner, and association was found between the use of this hygiene instrument and DMF-T.
With respect to the DMF-T index, the WHO recommends that at twelve years of age, this should be equal to or lower than 3.0 19 .In the Brazilian case, this goal was observed by SB Brasil 2003 24 when the index attained 2.78, presenting a decline to 2.07 in 2010 (SB Brasil 2010). 3Nevertheless, because it is a per capita value, it does not reflect the reality of all the regions 4 , considering that in the Northeast the goal was only attained in 2010 (DMF-T = 2.63) 3 .In this study we identified a mean DMF-T value of 3.67, with a median of 3.0 for the sample of schoolchildren, this result being lower than that found in the Brazilian Northeast for adolescents from 15 to 19 years of age (4,53) 3 .
Approximately half of the adolescents presented a DMF-T equal to or lower than 3, corroborating the findings of Cangussu et al. 25 and Rocalli et al. 26 .The reduction in the dental caries indicators in Brazil is clear, and has been demonstrated in population-based studies 25 .This important trend towards decline in caries is linked to the spread of access to services, greater perception of oral health diseases and exposure to fluoride, considered the main factor for local control 3,26 .
Relative to erosive lesions, 18.4% of the sample presented lesion in at least one tooth, similar to the findings of Gurgel et al. 8 and Mangueira et al. 10 .Over the course of the last decade there has been a significant increase in the prevalence and severity of erosive dental wear, particularly in children and adolescents 9,14,27 .In modern society dental erosion is known to be an important cause of loss of dental structure 9,14,23 .
Relative to the severity of erosive lesions, the majority of the participants presented lesion only in enamel, corroborating the findings described by Huew et al. 27 and Mulic et al. 28 .With reference to localization, the vestibular surface was the most affected, according to Dukic et al. 29 ; a fact due to the close contact with potentially erosive beverages (sodas and citric juices).
The smooth silky appearance with absence of periquimacies and intact enamel along the gingival margins are some of the typical signs of enamel erosion on these surfaces [27][28] .If left untreated, erosion may cause sensitivity, discoloration and change in the shape of teeth, resulting in esthetic and functional compromise 25 .
There was no significance in the concomitant manifestation of erosive lesions and DMF-T.This result may be explained by the fact that erosion is the chemical dissolution of dental enamel cause by acids without bacterial involvement 25 , thus, in principle, it has etiologic factors that differ from those of dental caries.These pathologies do however, have one and the same risk factor -high consumption of foods rich in sugar, which in general have high erosive potential 30 .Some of the methodological limitations of the present study must be observed; among them the fact that the study has a cross-sectional design in which the outcome corresponds to a single moment in time.Another aspect to be pointed out was the initial resistance of some of the schools or teachers to receiving the researchers, because they did not understand the importance of studies for the planning of actions in oral health.

CONCLUSION
The use of dental floss and other means of oral hygiene were unsatisfactory.The mean DMF-T found was 3.67, median 3.0, minimum 0 and maximum of 15 was considered moderate and below the value reported for the Brazilian age group, but varying considerably.The prevalence of dental erosion with lesions predominantly in enamel was found among the adolescents.

Table 1 .
Distribution of schoolchildren according to use of dental floss, tongue cleaner and mouth wash, according to sex.Campina Grande (PB), 2012.

Table 3 .
Distribution of schoolchildren according to presence of erosion and DMF-T.Campina Grande (PB), 2012.

Table 4 .
Characteristic of dental erosion in rate of affected teeth.