INTRODUCTION

Dental caries is a public health problema¹, defined as a chronic prevalent condition by the World Health Organization. Peru studies, although not current, report dental caries in 60%-90% of school-age children. Other oral diseases can affect the living conditions and health of the population, especially in children². Preventive measures for dental caries should be explained to parents, while health professionals should apply other measures. In this sense, while sugars and fermentable carbohydrate consumption should be avoided in the child's diet, toothbrushing and flossing, and 0.05% sodium fluoride rinses should be used in children over 6 years old with high caries risk³.

Toothbrushing is a fundamental self-care behavior for protecting oral health. It is considered a social norm that should be done at least twice a day⁴. In addition, there is strong evidence from systematic reviews that toothbrushing with fluoridated toothpaste is effective in decreasing the prevalence and intensity of caries^5,6. Thus, toothpaste should contain more than 1000 parts per million (ppm) of fluoride and should be used in age-appropriate portions. However, a study indicates that some Peruvian children do not brush their teeth daily⁷. Preventive programs in oral health should promote healthy habits from an early age, considering that oral diseases in advanced stages are the fourth most costly health problem to treat⁸.

Peru and the entire world were affected throughout the pandemic caused by coronavirus 2019 (COVID-19) due to its high transmissibility.

As a result, governments adopted preventive measures such as distancing and mandatory social immobilization, which negatively impacted accessibility to health care, and dental care was also affected. As for dental care, it was recommended to delay or avoid visits and treat only emergency cases to prevent the possibility of cross-contagion by aerosols. Due to limited access, oral diseases increased in prevalence. Finally, it is essential to know that children did not brush their teeth permanently, given that the years compared in this study are included with the beginning and continuation of the pandemic.

Therefore, this research sought to determine the practice of toothbrushing in children under 12 years of age in Peru between 2019 and 2021.

METHODS

A cross-sectional, analytical, and retrospective study was conducted using the Demographic and Family Health Survey (ENDES) database developed by the National Institute of Statistics and Informatics (INEI) of Peru during the years 2019, 2020, and 2021. The ENDES has a two-stage, probabilistic, balanced, stratified, and independent sample design classified into the rural and urban areas at the departmental level. The ENDES uses three questionnaires, but only the “Health Questionnaire” includes questions about general toothbrushing, daily toothbrushing, and toothbrushing at least twice a day for children aged 0 to 11 (Section 8). This section contains questions about the child's toothbrushing that can be answered by a person older than 15 years (parents or caregivers).

Only records taken from persons under 12 years old were considered, gathering a total of 167 750 records in 2019, 177 414 records in 2020, and 168 145 records in 2021. However, not all subjects were evaluated in the study variables. Therefore, the final sample size was 38 201 records in 2019, 18 611 records in 2020, and 35 758 records in 2021, including those who responded about toothbrushing^9-11. As inclusion criteria, only the records of individuals under 12 years of age from the Peru Demographic and Family Health Survey of 2019, 2020, and 2021 referring to toothbrushing were incorporated.

This study established 2019, 2020, and 2021 as independent variables and general toothbrushing as the dependent variable, which refer to whether children perform this practice (QS809: (NAME) brush their teeth with a toothbrush?). Daily toothbrushing, defined as on whether they brush their teeth daily (QS810: (NAME) brush their teeth every day?) and minimum toothbrushing two times a day, referring to whether they brush their teeth between 2 or more times a day (QS811: (NAME) how many times a day do they brush their teeth?). Likewise, some covariables were presented as the natural region of residence, being classified in Metropolitan Lima, rest of the coast, highlands, and jungle; the area of residence was divided into rural and urban areas; the place of residence was classified into large city (capital), small city, town and countryside; altitude of residence was defined as less than 2500 meters above mean sea level (MAMSL) and from 2500 MAMSL and more; the wealth index was categorized from the 1st to the 5th quintile, referring to the people of a population distributed in 5 groups according to their economic level, from the poorest to the richest. The age was divided into two groups: 0 to 5 years and 6 to 11 years, and sex was divided into man and woman.

The first step for the research was to access the INEI website. Todo so it was required to click on "database," follow by "microdata," and then to click on "survey query." In that window, we proceeded to type "Demographic and family health survey" in the search engine, and we chose 2019, 2020, and 2021 as the selected period. Once each database had been downloaded, they were merged using the STATA statistical software. Incomplete records were eliminated from the new database to perform the final data analysis.

STATISTICS

The statistical program used was STATA SE/15.1, with a confidence level of 95% and a p<0.05. We began with a descriptive study for each variable to obtain the absolute and relative frequencies. Then, we proceeded with the bivariate study using the chi-square test to measure the association of the studied variables. Finally, Poisson regression was used for the multivariate study to find crude prevalence ratios (PR) and adjusted prevalence ratios (aPR). Two models were generated: one crude and the other adjusted, in wich the years 2019, 2020, and 2021 were considered as independent variables. The dependent variables were general toothbrushing, daily toothbrushing, and toothbrushing at least twice daily. For the adjusted models, the covariates were those previously reported that have achieved bivariate association: natural region of residence, area of residence, place of residence, altitude of residence, wealth index, health insurance coverage, age, and sex. The svy command was used to have representative estimates because the survey design where sampling patterns are specified in the stratum, primary sampling unit, and weights was incorporated into this data study.

ETHICS

To begin the administrative processes, consent was requested from the Integrated Unit of Research, Science and Technology Management of the Faculties of Medicine, Stomatology and Nursing, obtaining its approval on July 21, 2022, with the code SIDISI No. 209189. Subsequently, the consent of the Institutional Ethics Committee of the Universidad Peruana Cayetano Heredia (CIE-UPCH) was requested and approved on August 8, 2022. It is essential to mention that the databases used publicly accessible on the official INEI website, where all records are coded, maintaining the anonymity of the respondents.

RESULTS

General toothbrushing was performed in 94.93 % (n=83 032) of the children, daily toothbrushing in 86.32 % (n=67 753) and minimum toothbrushing twice a day in 82.93 % (n=53 824). 31.42 % (n=6 281) of the sample came from Metropolitan Lima, 76.50 % (n=35 630) from the urban area, 31.42 % (n=6 281) from the capital, and 78.25 % (n=37 704) live at less than 2 500 MASML. 22.85 % (n=13 198) were poor, 76.61 % (n=75 291) had health insurance, 72.85 % (n=49 455) were male, and 58.33 % (n=40 735) were aged 6 to 11 years. In a bivariate manner, general toothbrushing and daily toothbrushing were associated with year, natural region, area of residence, place of residence, altitude, wealth index and age; minimum toothbrushing twice a day was associated with year, natural region, area of residence, place of residence, altitude, wealth index, health insurance holding, sex, and age (Table 1).

According to the multivariate analysis, the year 2020 presented a negative association only with daily toothbrushing (aPR: 0.97; 95CI %: 0.96-0.99; p<0.001) and toothbrushing minimum twice a day (aPR: 0.96; 95 %CI: 0.95-0.98; p<0.001). The year 2021 presented negative association with general toothbrushing (aPR: 0.98; 95 %CI: 0.97-0.98; p<0.001), daily toothbrushing (aPR: 0.97; 95 %CI: 0.95-0.98; p<0.001) and toothbrushing minimum twice a day (aPR: 0.94; 95 %CI: 0.92- 0.96; p<0.001), adjusted for the previously associated covariates (Table 2). These results show that 2021 boasted a lower probability of toothbrushing frequency compared to 2019, considering the three variables used to measure toothbrushing. The same occurred in 2020, except for general toothbrushing, compared to the same reference year.

DISCUSSION

Inadequate oral hygiene that does not include fluoridated toothpaste will result in a high caries risk and gingivitis. Consequently, there is broad consensus that oral hygiene behavior is essential for everyone and should begin with the eruption of a child's first tooth¹². Correct practice will help keep the oral cavity clean and healthy to prevent disease. Worldwide, more than 530 million children suffer from primary tooth decay, and research on risk factors associated with poor oral health indicates that preventive measures are the key to good hygiene, with toothbrushing being the most common and effective means¹³.

A study published in 2019 indicates that less than a tenth of Peruvian children do not brush their teeth; the majority are between 1 and 5 years old. This could be attributed to the fact that at this age, they require help to brush⁷. Garcés-Elías et al. observed that the year of the outbreak of the COVID-19 pandemic negatively impacted daily toothbrushing and its frequency of at least twice a day. They also evaluated whether the changes caused by the COVID-19 pandemic would have affected the oral health of people, finding a reduction in the frequency of toothbrushing¹⁴. Gotler et al. reported an increase in the diagnosis of carious lesions in children who visited the dentist after the confinement period, compared to previous years¹⁵. The present study obtained similar results, showing an association between the COVID-19 pandemic and toothbrushing frequency. The years examined coincide with the pandemic period, revealing a negative association between this event and the maintenance of a daily toothbrushing routine, whether general or at least twice a day. These findings significantly highlight how a health emergency can notably impact oral health care.

Regarding toothbrushing at least twice a day, the current research associated this practice with the following geographic characteristics: natural region, area of residence, place of residence, and altitude. Martin et al. studied households of children under three years of age with low economic income and lived in urban areas; about half of the parents reported brushing their children's teeth twice a day¹⁶. In addition, an analysis conducted in Peru revealed that access to health services in rural areas is significantly lower compared to urban areas, reflecting a decrease in adequate toothbrushing frequency⁸. Similarly, regarding daily tooth brushing, an investigation found that the percentage of children who did not brush their teeth were under the care of guardians with a low level of education, which is characteristic of rural areas of Peru⁷. Concerning the above, this research worked with children under 12 years of age, showing that toothbrushing frequency was lower in rural and remote areas.

Sociodemographic characteristics, such as wealth index, age, sex, and possession of health insurance, were also associated with this analysis. It was found that people with low economic income were less likely to brush regularly, especially among children aged 0 to 5 years, who proved to be more diligent in this hygiene practice. Regarding sex and availability of health insurance, no significant effect on brushing frequency was observed. In addition, another study highlighted the adverse impact of economic factors on the oral health of students¹⁷. Casanova-Rosado et al. studied the frequency of tooth brushing in Mexican schoolchildren, finding that girls brushed their teeth more than boys and that children who had visited the dentist in the last year before the analysis were more constant in this practice¹⁸, different from the results obtained in this investigation, where boys were the ones who brushed more than girls. Finally, a study in Australia on the influence of high socioeconomic level on tooth brushing shows that two-thirds of Australian children brush their teeth two or more times a day and that the mean age of initiation of tooth brushing with fluoridated toothpaste was 24 months. This may be influenced by parental education level and income above US$76 159, with this value being the equivalent in Australian dollars approximately¹⁹. On the other hand, the development of this research may have had limitations due to its cross-sectional design, preventing the establishment of causal relationships with the events studied. In addition, by using a secondary data source, there is a high possibility of presenting memory and information biases due to the answers provided by the participants, who may not remember the events accurately.

Finally, parents more concerned about their children's dental hygiene had a higher economic level. There are still less than a tenth of children who do not brush their teeth, most of them under six years of age, which could be explained by the low wealth index of the families or by the lack of parental support in exercising healthy practices such as tooth brushing. It should also be considered that the remoteness of some health centers in rural areas has a strong influence on these healthy practices, such as having health insurance. It is crucial to remember that good oral health will help to have healthy teeth and gums; tooth brushing is a fundamental habit that should be instilled in children from an early age. Poor oral hygiene and little education on the subject are still a concern. Therefore, laws, health promotion, and disease prevention should be reinforced. This helps raise awareness among the population. Moreover, brushing teeth with toothpaste containing at least 1000 ppm is recommended.

CONCLUSION

This study concludes that the frequency of toothbrushing decreased in Peruvian children under 12 years of age according to the Demographic and Family Health Survey during the years 2019 to 2021, whose associated factors were natural region, area of residence, place of residence, altitude, wealth index, health insurance tenure, sex, and age. Lastly, the studied years were negatively associated with general, daily, and minimum twice daily toothbrushing.