Socioeconomic Disparities in the Self-Perceived Oral Health, Missing Teeth and Dentures in the Adult Population of Serbia

Oral health refers to health of the teeth, gums, and entire oral-facial system. Good oral health is in direct relation with eating, speaking, communication, and also influence self-confidence. It is under the influence of many internal and external factors, such as diseases, type of diet, bad habits, drugs and medication and many more, so the proper prevention is necessary to be involved in each age group, focusing on keeping the oral health on the highest level (1).

Oral diseases are a major public health problem for countries and populations worldwide, although they are often not publicly recognized as such. Oral diseases are a group of different disease entities with their own etiology and burden, and different possibilities for their prevention, care and rehabilitation (2).

Those diseases are not discriminating towards the gender, income or country development, but they do tend to be more prominently common in the developing countries because the public health system often does not include the dental health insurance (3,4). There are broad diapason of these diseases that could lead to loss of one or more teeth, like dental caries (in any type of dentition), paradontopathy, gum diseases, but also the injures in the sport and other accidents (5). Lost teeth, anterior or the posterior brings along problems with self-esteem, mastication, and esthetic is endangered due to the visibility of lost anterior teeth. So there are many components that must be observed. It is showed that missing teeth can impact the older and younger people in different ways where older group associate losing teeth with aging and younger group decrease social interaction due to poorer estetics (6).

Untreated caries of permanent teeth is the most widespread dental disease, followed by paradontopathy and those are the main reasons of why people have poor self-perception about their dental health (7). Dental caries is the chronic disease of had tissue of the teeth that with different symptomatology. It is not uncommon to be combined with the soft tissue problems, like gingivitis (gum disease) and combination of those two deepened the symptoms that lead to gum bleeding, bad smell, and overall increase the poor oral hygiene. People of any age with these problems will have issues in interaction with other people, at their job, self-esteem and eventually that can, in the long term, influence their mental health, and lot of studies links it with depression, anxiety and lost teeth with lover cognition levels (8).

For example, the parodontopathy is the disease that usually follows the older age, especially generalised parodontopathy. This leaves elderly people missing the group of teeth or all of them. The car accidents are statistically more common in the younger and middle age people and sport accidents and dental caries are more common in the adolescents and high school children. Loosing teeth can happen anytime, and treatments options may differ from age groups, but the common fact is that the missing teeth must be replaced due to short-terms and long-term complications (9). There are different therapies for replacing missing teeth, and they can vary from dental bridge and dentures to the implant therapy. Depending of the personality type, those therapy plans can be differently accepted and many people, because of the way of how they perceived replacement of lost teeth can be very problematic and not realistic in their demands (10). That’s why many older people choose not to wear the dentures, decline the therapy options or demand the implant therapy, although usually there are not indicated for demanded therapy.

Most oral diseases are preventable through self-care or simple, evidence-based and cost-effective population-wide measures, including action on the broader social, economic and political determinants of health, enabling significant reductions in disease burden and limiting negative impacts (11).

The dramatic increase in the global number of oral disease cases represents a huge burden on health systems. The main causes of oral health inequalities are often complex and linked to historical, country-specific, economic, cultural, social or political factors. The conditions in which people are born, grow, live, work and age and the structural drivers of those conditions - the unfair distribution of power, money and resources in society - are the basic social determinants of inequality in oral health (12).

The aim of this study was to assess the self-perceived oral health, the presence of dental prosthetics and missing teeth number in the adult population of Serbia and determinate the socio-economic inequalities within.

The study represents a secondary analysis of data obtained from the fourth National Health Survey of the Republic of Serbia, which was conducted by the Ministry of Health of the Republic of Serbia in accordance with the recommendations for the implementation of the European Health Survey in 2019. (13).

The research was conducted as a descriptive, cross-sectional analytical study on a representative sample of the population of Serbia. The primary target population consisted of all persons aged 15 and over living in private (non-institutional) households in the Republic of Serbia. The excluded persons were the ones living in collective households (student dormitories, dormitories for children and youth with disabilities, homes for socially endangered children, retirement homes for seniors, care homes for the elderly and infirm, adult disability homes, monasteries, convents, etc.). Stratification was performed according to the type of area (urban and other) and the four regions: the Belgrade region, the Vojvodina region, the Sumadija and Western Serbia region, and the Southern and Eastern Serbia region. For the purpose of this study, data on the adult population aged 20 years and older were used and total of 12.439 participants were included.

Ethical standards in the Health Research of the Serbian population are in accordance with the international Declaration of Helsinki, adopted at the General Assembly of the World Medical Association in 1964, and improved by amendments as of 2013, as well as the legislation of the Republic of Serbia. In order to respect the privacy of the research subjects and the confidentiality of the information collected about them, all necessary steps were taken in accordance with the General Data Protection Regulation (GDPR), a new European legal framework that prescribes the way to use citizens’ personal data, as well as with the national Law on the Protection of Personal Data, the Protection Strategy personal data and the Law on Official Statistics with the application of the principle of statistical confidentiality.

The research instruments were: a household info panel, which was used to collect information about all household members, i.e. about the socio-economic characteristics of the household itself, and a questionnaire for self-completion.

For the purposes of this research, the following socioeconomic variables were used: gender, age, marital status and region, education, employment status, and wellbeing index, while the variables related to oral health were self-rated oral health, missing teeth, and the presence of dentures.

All data of interest are presented and analyzed by adequate mathematical-statistical methods appropriate for the data type. Chi-square test (χ²) test was applied to test the difference in the frequency of categorical variables while the descriptive statistics of numerical variable was used for presenting the mean and standard deviation and categorical variables were presented as percentage. Multinomial logistic regression was also performed. All results with the probability that is equal to, or less than 5% (p ≤ 0.05) were considered statistically significant. Statistical analysis was performed using a commercial, standard IBM SPSS software package Version 19.0. (The Statistical Package for the Social Sciences software) (Version 19.0., SPSS Inc., Chicago, IL).

The research was conducted in 2019, during which a total of 12.439 people aged 20 and over were surveyed. The average age of all subjects was 52.8±17.7 years, with women being significantly older than men. The largest number of respondents were married or cohabiting (63.2%) and from the region of Šumadija and Western Serbia (32.0%). The largest number of respondents completed secondary school (56.4%), whereby women significantly more often had primary and lower education than men (p<0.001). The material condition of the respondents, assessed on the basis of the welfare index, shows that the largest percentage belongs to the poor category (40.4%). When it comes to the work status of the respondents, it turns out that almost two thirds of the respondents (61.4%) were unemployed or inactive. Men were employed significantly more often (42.9%) than women (32.2%) (p<0.001). The sociodemographic characteristics of the respondents by gender and overall are shown in Table 1.

In the self-assessment of oral health (condition of the mouth and teeth), the largest number of respondents rated it as good (32.7%), followed by average (22.9%), bad (18.9%), and very good (14.5%).

Regarding the lack of teeth, almost every third respondent lacks 1 to 5 teeth (31.7%), while 17.6% of respondents have all teeth. Every fourth respondent (23.0%) stated that they did not have more than 10 teeth, while every ninth respondent did not have any teeth (11.2%).

Total dentures are the most common dental restoration that the largest number of our respondents have (14.6%), followed by partial dentures that 11.9% of respondents have, 9.4% of them have fixed dental restorations, and only 3.4% have implants. If we look at the self-assessment of the condition of the teeth and gums in relation to the demographic characteristics of the respondents in Table 2, it is noted that the condition of the teeth and gums is assessed as very bad to a slightly higher degree by male respondents (6.1%), (p<0.001), aged 65 and over (64.0%), (p<0.001), who are in a married/cohabiting (58.9%), (p<0.001), and who were from the Šumadija region and Western Serbia (31.5%), (p<0.001). Also, it is noted that the condition of the teeth and gums is assessed as very bad to the greatest degree by respondents with the lowest education (54.5%), (p<0.001), the poorest (55.9%) (p<0.001), and inactive in terms of work status (77.5%), (p<0.001).

Regarding the lack of teeth (including implants), it is noted that 62.9% of female persons reported the lack of all teeth, significantly more often than men who reported the lack of teeth in 37.3%, followed by respondents of the oldest age group 65 and over (74.5%), who were married/cohabiting (54.5%) and who were from Vojvodina (30.7%). Looking at the lack of all teeth (including implants) according to the socioeconomic characteristics of the respondents, we see that they are most often respondents with the lowest education (50.5%), from the poorest (46.4%) and inactive in terms of work status (83.5%) (Table 3).

The presence of dental restorations in the adult population, according to demographic characteristics, is such that all types of prostheses are more often worn by women, married or cohabiting, from the region of Šumadija and western Serbia, while in terms of age, the oldest age group of 65 and over most often had total or partial dentures and fixed prosthesis, while implants were more often done in respondents aged 35 to 64 (69.2%). According to socioeconomic characteristics, the presence of dental restorations in the adult population was most often in respondents with secondary education. Total dentures were most often worn by the poorest (41.5%), while partial, fixed and implants were most often worn by wealthiest respondents (40.8%, i.e. 51.9% and 54.6%), while when it comes to work status, inactive ones mostly have total dentures (81.0%) had partial dentures (66.1%), while respondents who were employed mostly had implants (Table 4).

Multinomial logistic regression analysis was performed to see the predictors of poor oral health with variables of dental status - different types of dentures and number of missing teeth. We concluded that statistically significant predictors of self-perceived poor oral health were people wearing total dentures, partial dentures, fixed prosthetics, implants and people missing 1–5, 6–10 and more than 10 teeth (p = 0.00). People wearing total and partial dentures were 2.2 (OR = 2.2) and 1.7 (OR = 1.7) times more likely to self-perceived health as bad. Also, people wearing fixed prosthetics and implants also were more likely to perceived oral health as bad (OR = 1.3 and OR = 4.0). Missing teeth are also contributing in a large amount in how people self-perceive oral health, mainly people missing 1 to 5, 6 to 10 and more than 10 teeth with odds ratio 25.3, 13.8 and 4.5 more likely (Table 5).

As the starting point of digestion and place where the most “estetic” organs are placed - teeth, oral cavity is of a great importance in various aspects of people’s everyday life and overall health. Socioeconomic factors are the ones that are mostly investigated regarding the influence on the good oral health, and poorer people with lower education, and also the elderly people are more endangered of have oral health issues and are prone to losing their teeth due to multiple comorbidities that are following the older age (14, 15). In Daviovic results, female, of the age between 35 and 65+ were more from urban living place had more like hood of having dentures (16). This findings are similar to ours where we also determinate female gender, in slighter older age groups 55–75, mostly married with high school level of education as the ones more commonly wearing the dentures - either partial or total.

Good health system definitely increases the better oral health if it’s included in the healthcare system. But this is something that is problem even in the more developed countries, and the countries that are developing are the ones mostly in the problem due to combination of all named factors (17). That’s why the global situation of the dental status is not so bright in developing countries. They tend to have higher incidence and prevalence of gum and hard tissue diseases and this is consequentially followed with the teeth loss (18). Losing only one tooth can be problematic because it may cause the movement of other teeth and can influence the therapy procedures of patients. Lesser number of lost teeth is something more common among younger population, where the leading cause of teeth loss are traumas due to accidents, fights and hard teeth tissue disease, like dental caries (19). One in five adults aged 20–64 years had one or more permanent teeth with untreated decay (20). The mean number of missing teeth increases with age, from 0.7 teeth at 20–34 years to 7.4 at 75 years and older. More than 1 in 10 adults aged 65–74 years had lost all their teeth and prevalence of edentulous among adults increased from 1.2% at 35–49 years to 19.7% at 75 years or older (21). In the study of Milosavljevic et al, the highest average number of missing teeth among the military insured’s was in the group of 35–44 years and it was roughly 6.5 while the most missing teeth in that age group was one to five (22). In our adult population, the highest percentage of people missed 1 to 5 teeth (31.2%) and number of teeth did decrease with age of participants and 37.5% of people older than 75 were edentulous. The soft tissue disease, paradontopathy, of oral cavity are more common in older and elderly people, and in combination with their current health status where certain medicaments and oral health conditions like xerostomia can increase degradation of oral health (23).

Study of Davidovic et al showed more than one third of their respondents describe their oral health as poor and very poor and over the half of them reported missing from one to ten teeth. Especially the younger adults, without partner, economically more stable and with a higher level of education perceived their oral health as good and they also had more natural teeth present (16). This is in line with our results, nearly one third or respondents described their oral health as poor or very poor (24.5%) and nearly half (47.2%) reported missing one to ten teeth. Lost teeth lead to problems with mastication and digestion, appearance, self-esteem, problems with temporomandibular joint, in case they are not treated properly and on time (24). There are also studies that investigated the impact of tooth loss to the people’s cognitive degradations (25). Nowadays there are many different options to compensate teeth loss, form dental bridges over the partial and total dentures to the many different options for dental implants, but still there are many disparities in the choice therapies in adults. Dental implants are becoming more utilized in the older adults even they are costly, because of their long-term durability (26). Half of the older adults, over the age of 65 had nearly 25% of dentures as their rehabilitation therapy for their lost teeth by Daviovic results (16). The most common therapy in rehabilitant lost teeth in our study was partial and total prosthetics - 26.5%. In German seniors aged 65–74 years was noted declining number of missing teeth from late 90s up to early 2000 and more than 35% had removable dentures and had on average 10 remaining tooth and higher incidence of periodontal diseases in comparison to the younger people (27, 28).

Although there is much on-going improvements in oral health, many people still suffer from chronic oral conditions and lack of access to the dental care they need which is also the situation in Serbia. Poor dental care affects the health care system and influence and dental health needs of people in the lower-income countries tend to overpower the number of physicians and increase the out of pocket spending (29).

Health of oral mucosa and hard tissues of teeth are crucial in keeping the ideal balance between function and aesthetics, and that is something that often may be underrated. Disease of teeth and oral mucosa are also connected to many different diseases and can influence the psychological aspects and quality of life (30, 31). That’s why prevention programs an education about their health must be implemented from early age, due to the different surrounding factors that also influence the opinions of individuals.

Socio-demographic inequalities in self-perceived oral health and dental status are present in the older adults, especially ones age 65 and more in Serbia. Reducing the inequalities among older people, economically less stable and educated can impact their oral health status and dental status which tend to be poorer. This will have impact to the national and individual economic burdens (32, 33).

Limitations of this study are that the factors of losing teeth are not included. It would be helpful to determinate the relationships between dentures, implants and missing teeth with most common reasons for their utilization/losing. Conducting additional research on this topic would be useful in future. Also, the data is limited only to people older than 20 years, where all named socioeconomic factors can influence the younger population self-perceived oral health too, as well as the missing teeth.

Self-perceived oral health of the highest percentage of respondents was rated as good, almost every third respondent lacks 1 to 5 teeth and most common dental restoration was total dentures. Condition of teeth and gums was assessed as very bad, more often by male respondents, aged 65 and over, married, lowest education and poorest. Regarding the lack of teeth females reported the lack of all teeth, in age group 65 and over, who were married. All types of dentures were more often used by women, married or cohabiting, while implants were the most common in respondents aged 35 to 64. Statistically significant predictors of self-perceived poor oral health were people wearing total dentures, partial dentures, fixed prosthetics, implants and people missing 1–5, 6–10 and more than 10 teeth. Given that numerous factors from the social and physical environment determine the choices of individuals, the prevention of oral diseases requires a multisectoral and multidisciplinary approach that combines the promotion of healthy lifestyles with activities that affect social and economic determinants, as well as the physical environment. The best results would be achieved by combining population strategies and strategies aimed at the most vulnerable categories of the population. Implementation of educational programs and preventive measures would contribute to raising awareness of the importance of oral health in older age groups. The findings of our study suggest that actions should address socioeconomic factors in order to reduce health inequalities.