INTRODUCTION
Allergic rhinitis (AR), asthma and dental caries are multifactorial diseases. Although the mortality rate associated with dental diseases is low, dental diseases indicate a significant deterioration in self-care and nutritional competence.
Although the pathogenesis of allergic diseases is controversial and unclear [1], AR is a common health issue, affecting approximately 25% of children and 40% of adults throughout the world [1]. AR is the most common chronic respiratory disease in childhood. Its prevalence has been reported as 11.8–36.4% in our country [2]. Even if AR patients do not receive treatment, they may develop dental diseases clinically as a result of excess cariogenic bacteria in the oral microbiota, dry mouth, constant mouth breathing, and complications from oral infections. As a result of the drugs (especially antihistamines) used in the treatment of AR, salivary secretion and the intraoral pH decrease. In this acidic environment, demineralization begins in the enamel layer of the tooth [3]. Tooth decay is defined as the destruction of the hard tissues of the tooth over time due to the acids produced by the bacteria within the plaque by fermenting the carbohydrates [4]. All of the issues above are among the key risk factors in the formation of dental caries in AR patients.
Asthma affects roughly 300 million people worldwide [1]. Although asthma is among the foremost chronic diseases seen in childhood, the prevalence of asthma is around 2–16% in Türkiye [5]. As the prevalence of asthma increases in children, it is important to examine how it affects oral and dental health [6]. It has been reported that possible cariogenic mechanisms are related to asthma drugs described in some studies [7]. A meta-analysis study conducted in 2011 determined that the risk of dental caries is twice as high in people with asthma [8]. The xerostomia effect of three groups of agents which are frequently utilized in the treatment of asthma – β2-agonists, anti-histamines and corticosteroids – is known [6]. For these and similar reasons, some studies have shown that asthmatic children have more dental caries, plaque formation and gingivitis compared to healthy children [9]. One month of treatment with inhaled β2-agonist and corticosteroid has been shown to result in a significantly reduced salivation rate and increased dental plaque index [10].
AIM
This study aimed to investigate whether there is a difference among the groups by performing oral and dental health screening in children with AR or asthma and healthy children varying in age from 6 to 12 in Sakarya.
MATERIAL AND METHODS
ORAL AND DENTAL HEALTH EVALUATIONS
In this prospective study, oral and dental health evaluations of the participants were made according to the dmft/DMFT (Decayed, Missing, and Filled Teeth) criteria [11], plaque index (PI) [12] and the Löe and Silness gingival index (GI) [13]. The evaluation of the participants was done by an assistant professor of pediatric dentistry at Sakarya University Faculty of Dentistry, Department of Pediatric Dentistry. We compared the effects of demographic characteristics, nutrition, and treatment duration on oral and dental health scores in three groups: AR, asthma and the control group.
SELECTION OF PARTICIPANTS
This study was carried out in pediatric allergy clinics of Sakarya University and outpatient clinics of Sakarya University Faculty of Dentistry, Department of Pedodontics between 8.03.2020 and 31.05.2021. Participants were randomly and voluntarily selected from patients diagnosed by a pediatric allergist based on the evaluation of individual symptoms and laboratory findings or followed up in our pediatric allergy outpatient clinic with a previous diagnosis of asthma and/or AR, and who had used medication in the last three months. A total of 63 participants, aged 6–12 years, diagnosed with asthma or AR and followed up in the allergy clinic were included in the study. Sixty-two children of similar age and gender, who were systemically healthy and applied to Sakarya University Faculty of Dentistry, Department of Pedodontics, were recruited as the control group.
INCLUSION CRITERIA FOR PARTICIPANTS
Age between 6 and 12 years.
Being followed up and taking medication due to the diagnosis of asthma or AR.
The participant has been using medication (treatment) for his/her disease for at least the last 3 months during his/her participation in the study.
Not taking antibiotics in the last 1 month.
Absence of additional chronic disease and/or dental disease.
EXCLUSION CRITERIA FOR PARTICIPANTS
Having additional chronic disease and dental disease.
Those with tooth loss due to trauma.
Those with chronic diseases affecting teeth such as gastroesophageal reflux (information was obtained through a questionnaire).
Medications used during permanent tooth development, oral and dental health care and needing dental treatment are critical for quality of life and health in the rest of life. For this reason, we conducted our study in children aged 6–12 years, when permanent teeth were developed. While evaluating the use of drugs, the number of months for drug use in the last years was evaluated retrospectively, provided that the drug was used for the treatment of the disease in the last 3 months.
It has been reported that the incidence of tooth erosion is 31 times higher in patients with gastroesophageal reflux disease [14]. Therefore, volunteers with gastroesophageal reflux disease were not included in the study. Volunteers with bone diseases, calcium metabolism defect, and malnutrition were not included in our study since tooth development, oral and dental health were primarily affected.
STATISTICAL ANALYSIS
The program SPSS Statistics for Windows, Version 22.0 (IBM Corp., Armonk, NY) was used for statistical analysis. Descriptive statistical methods (mean, standard deviation, percentage, minimum, maximum) were used when evaluating the study data. The conformity of the quantitative data to the normal distribution was tested with the Shapiro-Wilks test and graphical examinations. One-way ANOVA test was used for the comparison of normally distributed quantitative variables between three groups. The Mann-Whitney U test was used in the evaluation of non-normally distributed variables according to two groups; the Kruskal-Wallis test was used in the comparison of three groups; and the post hoc Dunn test with Bonferroni correction was used to determine the significance of group differences. Spearman’s correlation analysis was used to evaluate the relationships between quantitative variables. Pearson’s χ2 test and the Fisher-Freeman-Halton test were used to compare qualitative data by groups. Statistical significance was set at p < 0.05.
RESULTS
EVALUATION OF DEMOGRAPHIC FINDINGS OF THE STUDY GROUPS
A total of 125 children, 30 of whom were asthmatic, 33 had AR, and 62 were healthy, were included in the study. No statistically significant differences were found in the age and gender distributions of the children between the groups (p > 0.05).
COMPARISON OF ORAL AND DENTAL EVALUATIONS OF THE STUDY GROUPS
A statistically significant difference was found between the DMFT measurements of the (asthma and AR) patient and healthy control groups (p < 0.05). DMFT measurements were found to be lower in the patient group (p = 0.034; Table 1).
Table 1
Distribution of dental findings in patient and healthy groups
In the asthma group, a statistically significant positive correlation was found between DMFT and PI (r = 0.398; p < 0.05; Table 2). As PI increased in the asthma group, the DMFT index increased. This is an expected situation explained in the mechanism of caries formation: as PI increases, we see an increase in the DMFT index. Similarly, in the asthma group, in accordance with the caries development mechanism, a statistically significant positive correlation was found between DMFT and GI (r = 0.461; p < 0.05; Table 2).
EVALUATION OF SURVEY FINDINGS OF THE STUDY GROUPS
In the daily eating routine, a statistically significant difference was found between the groups in lemonade, cola, and sports drink consumption levels (p < 0.05; Table 3). When examined with Dunn’s test, the consumption rate in the asthma group was found to be significantly lower than in the healthy group (p = 0.013; p < 0.05; Table 4).
Table 3
Evaluation of daily eating routine in patient and healthy groups
Table 4
Evaluation of daily eating routine by group
There was a significant difference between the groups in jam/honey consumption levels (p < 0.05); when examined with Dunn’s test, the rate of intake in the AR and asthma group was found to be significantly lower than in the healthy group (p < 0.05; Table 4).
When the biscuit consumption of the participants was compared statistically between the AR, asthma and the healthy group, it was found that the participants in the healthy group consumed biscuits significantly less frequently (p < 0.05; Table 5).
Table 5
Biscuit consumption frequency compared between patient and healthy groups
| Biscuits | Patient | Healthy | P-value |
|---|---|---|---|
| n (%) | n (%) | ||
| Several times a week or more rarely | 34 (53.7) | 57 (75.8) | 0.001 |
| Daily or more often | 29 (46.3) | 15 (24.2) |
It was found that the patient (asthma and AR) group had higher water drinking rates than the control group (p = 0.01).
When evaluating the drug use of the participants, the number of months they had used drugs since the beginning of the treatment was evaluated retrospectively, provided that the drug was used in the last 3 months. A statistically significant, but weak, negative correlation was found between DMFT and duration of drug use (r = –0.252; p < 0.05; Table 6).
Table 6
Relationship between DMFT, plaque index and gingival index according to the duration of treatment
| Drug use period (years) (n = 63) | DMFT | PI | GI |
|---|---|---|---|
| r | –0.252 | 0.116 | –0.031 |
| P-value | 0.047 | 0.365 | 0.807 |
The number of people in the house also differs significantly according to the groups (p < 0.05). The proportion of participants with seven or more people in the household in the AR group was high. The proportion of medium extended families in the asthma group and the proportion of nuclear families in the healthy group were also high.
Smoking rates were significantly different between the study groups. The rate of exposure to cigarette smoke in the patient group was higher than in the control group (p = 0.001; Table 1).
DISCUSSION
It has been reported in the literature that some medications used in the treatment of allergic rhinitis and asthma affect oral and dental health. These drugs include antihistamines, nasal and oral inhaled steroids, β-agonists, etc. Antihistamine agents are known to reduce salivary secretion. The use of nasal steroids, which affect oral pH, is important to evaluate the effects on oral and dental health. The incidence of tooth decay is higher in children who exclusively use β-agonists than use β-agonists and corticosteroids together, as the study by Khalilzadeh et al. demonstrated [8, 15, 16].
Since the average household size in the AR group is high, this result of our study is contradictory to the relationship between allergic diseases and the hygiene hypothesis as well as general literature. The extended family, lifestyle, and the high household size in the asthma group indicate that secondary care and follow-up of the health status of the child will be limited. The nuclear family lifestyle in the healthy group is consistent with the low number of people in the household and the higher care and health status of existing children. This suggests that the hygiene hypothesis by itself is not sufficient to explain the development of allergic disease.
Mother’s education level, mother’s occupation and father’s education levels do not differ statistically significantly according to the groups, and this result of our study is unexpected because the mother is primarily liable for childcare and health, which may be a traditional feature in our society. It is necessary to examine the effect of the education level of the mother in the family, which is the smallest unit of the society where people receive their first education and learn cleaning and personal care, with a larger scale study. Also, in the study of Shashikiran et al., the high rate of caries in children with asthma was found to be related to factors such as socio-economic level and oral hygiene habits [17].
When fathers’ occupations were examined, the proportion of workers was found to be significantly higher in the AR and asthma groups. However, when the income levels were examined, no significant difference was found among the groups. It means that the study did not provide strong evidence for a relationship between low socio-economic level and asthma and/or AR. With this unexpected result, our study does not corroborate findings reported the literature [17–19]. Since the developmental stages of such allergic diseases and the severity of the allergic disease are determined by more than one factor, larger studies with many participants are required to determine a statistically significant difference.
In our study, when the significant difference between the groups in terms of lemonade, cola and sports drink consumption levels was examined by Dunn’s test, the consumption rate in the asthma group was found to be significantly lower than in the healthy group. One of the reasons that emerged for the lower DMFT index in the asthma patient group when the dietary habits were closely examined was lower cariogenic food and beverage consumption. While our study result contradicts the study of Celenk and Ayna [20], the studies of Morikava et al. [21] and Akarslan et al. [22] support our study result. Chewing sugar-free or xylitol gum would be a suitable recommendation as a habit to increase the flow rate of saliva.
When examining the levels of jam/honey consumption between the groups, when the significant difference between them was examined by Dunn’s test, the rate of use in the AR and asthma groups was found to be significantly lower than in the healthy group. Since they are very sticky foods, the residence time on the teeth is very long, and therefore the effects of caries could be very high.
Despite higher biscuit consumption, we found that the cariogenic factor of our patient group was low due to lower consumption frequency of lemonade, cola, sports drink, jam, honey as well as higher water drinking rates.
DMFT measurements were found to be statistically significantly lower in the patient (AR and asthmatic) groups. This result suggested that the smaller the bacterial colony was in the oral flora in allergic diseases in the patient group diagnosed with AR and asthma, the less was the development of secondary dental caries; in other words, the hygiene hypothesis was supported [23]. The low cariogenic factor detected in the patient groups in this study also supports this conclusion [24].
A statistically significant relationship was found between DMFT and duration of drug use in a negative direction (DMFT index decreases as the duration of drug use increases). However, we expected a positive relationship between the duration of drug use and DMFT in accordance with the literature [25]. Therefore, this result is the opposite of what was expected. However, the increase in the duration of drug use could be associated with more severe allergic disease and more hygienic conditions. On the other hand, as the disease’s severity decreases with treatment, so does the negative influence on saliva secretion in the oral cavity and the pH balance of the oral mucosa [26, 27].
It was determined that the rates of smoking and tobacco exposure were higher in the patients than in the control group. This is an additional factor that increases the severity and symptoms of their allergic diseases. It is known that exposure to cigarette smoke exacerbates asthma and allergic rhinitis symptoms [28, 29]. Furthermore, our study demonstrates the statistically significant harmful consequences of this exposure on children’s oral and dental health.
This study has some limitations. Since the developmental stages of such allergic diseases and the severity of the allergic disease are determined by more than one factor, larger studies with many participants are required to determine a statistically significant difference. However, since our study was conducted during the pandemic period, the number of participants was limited. Nevertheless, the statistically strong and significant results encourage further studies on this subject.
CONCLUSIONS
Awareness of both allergists and dentists about the effects of AR and asthma on oral and dental health should be increased, and this awareness should also be increased in all branches of medicine and dentistry as well as the general society. When planning treatment, it is critical to consider the potential side effects of the treatment and to inform the patients and their families about the necessary preventive measures.
