Caries and periodontal diseases are among the most common diseases of modern society (1, 2). According to the WHO data, 60-90% of schoolchildren and almost 100% of the adult population suffers from caries (2). Apart from caries, periodontitis is one of the most important causes of tooth loss and epidemiologically speaking, it is a public health problem worldwide (3). About 30% of world population aged between 65 and 74 do not have any natural teeth (2). Periodontitis also affects general health and is related to cardiovascular diseases, stroke, diabetes, premature childbirth and low birth weight as well as aspiration pneumonia (4-6). Since over 90% of oral diseases can be prevented, prophylaxis plays an important role in dental medicine, particularly from a public health perspective (7). The development of modern dentistry is based on investments in prevention and development of modern clinical procedures based on scientific concepts (7, 8).
Results of research show that caries incidence in children and adolescents in developed countries is decreasing while in developing countries it is very high (9). In Croatia, the awareness about the importance of oral health and its effects on general health is lacking, which ranks Croatia along with the least developed European countries (9-11). This is supported by the fact that Croatians use 3.5 toothpastes and 0.6 toothbrushes during the year (12). According to the WHO data, 49% of the world population have DMFT index value of 3 (the sum of carious, extracted and filled teeth) whereas in most EU countries the value ranges from 0.5 and 1.5 (9). According to the same source, the DMFT value in Croatia is assessed to be around 3.5. The caries incidence is directly related to the economic and social development of society (1, 2). The results of research done in the Zagreb area show that 4.1% of subjects have juvenile and progressive periodontitis and as many as 82% have gingivitis (13).
The oral status of an individual depends on their oral hygiene habits, way of life, economic status and frequency of visits to the dentist (14). Children and adolescents have a higher risk for caries and the etiological factors are related to lifestyle, increase total and frequent intake of carbohydrates, sweets and sweetened beverages (7). If the teeth are inadequately brushed, a biofilm forms on them and it is the main cause of caries and periodontal diseases (15, 16). Since caries and periodontal diseases can be controlled if the appropriate oral habits are adopted, they are considered behavioural diseases (17). However, the results of research show that young people in Croatia are insufficiently educated on prevention and do not recognize the link between their own behaviour and the risks it carries (14). The level of health awareness depends on the successful communication between the patient and the health professional that is, sharing of information relevant for maintaining good health. The fact that up to 50% of patients do not understand what the doctor is telling them is alarming (8). During their studies, dental students acquired knowledge on oral health, treatment of oral diseases, prevention and control and also improved their perception of oral health, resulting in their better oral status (18, 19). In 1991, the DMFT index in Croatia amounted to 2.6 and in 1999 it was 3.5 (20). This increase in the DMFT index was probably the result of primary healthcare reform in which the systematic dental prevention in kindergarten and school children was lost and a new system has not been established (20).
The aim of the study was to examine the attitudes of dental students and students of technical sciences and humanities towards oral health and to compare their oral statuses as well as the results of plaque indices in three groups of subjects.
Subjects and methods
This research was carried out at the Department of Endodontics and Restorative Dentistry at the School of Dental Medicine, University of Zagreb. The Ethics Committee of the School of Dental Medicine in Zagreb approved the research. After the patients had given their informed consent to use their data for scientific purposes, the research started.
The study comprised 58 subjects aged between 20 and 28, all of them undergraduate students at the University of Zagreb. They were divided into 3 groups according to the college they attend:
The subjects filled in a questionnaire which consisted of the following three questions:
How often do you brush your teeth?
How often do you visit the dentist?
How important is oral health to you?
A probe (PCP-11, Hu-Friedy, Chicago, Illinois, USA) and a dental mirror (Roeko, Langenau, Germany) were used for the intraoral examination with a standard dental light (20 000 lux). The number of teeth, fillings and caries was determined by the oral examination. Subsequently, the DMFT index which stands for the sum of decayed, filled, and missing teeth was calculated based on these data. Teeth extracted due to orthodontic anomalies, dental trauma or congenital anomalies were not included in the count.
The subjects were given a plaque disclosing tablet Mira-2-Ton® (Hager Werken, Duisburg, Germany) which they melted in their mouth and then the plaque index was recorded (Plaque Control Record) according to the method by O'Leary et al. (15). Each tooth was divided into four surfaces which were then checked for plaque.
83% of subjects stated that they brush their teeth 2-3 times a day, and 17% of them stated that they brush more than 3 times a day and all of them were students of Dental Medicine (Figure 1).
With respect to the frequency of visiting the dentist, 28% of subjects stated that they visit every 6 months; most of them students of dental medicine, and only 3 of them were from other colleges. Yet, the most common answer was ‘as needed’ (Figure 2). The subjects’ attitudes towards oral health are shown in Figure 3.
There were no statistically significant differences between the values obtained by comparing the DMFT index in the three groups of subjects (p=0.1004; f=2.4) (Figure 4).
A statistically significant difference was found between the plaque index values in the groups (p=0.0018; f=7.14) (Figure 5).
The results refuted the null hypothesis by showing that there is a difference between dental students and students from other colleges. Dental students who participated in the research were all students of the 5th and the 6th year which means that they have already acquired knowledge on oral health, treatment of oral diseases, prevention and control thus modifying their attitude towards oral health, resulting in a better oral status and lower plaque index value (18, 19). It is therefore unsurprising that 48% of dental students stated that they brushed their teeth more than three times a day whereas in other groups there were no subjects who chose this answer, that is, most of them chose the ‘2-3 times a day’ option.
Apart from knowledge on oral hygiene which dental students have, the availability of dental care plays an important role because many of the dental students’ parents are dentists themselves (18) and the students get to be the patients during practicals.
Since 98% of subjects stated that oral health is very important to them, we can conclude that the perception of oral health is on a high level. However, the perception of oral diseases is on a significantly lower level, which is reflected in the high values of DMFT index and less frequent visits to the dentist. This is consistent with the results obtained by Pellizzer et al. according to whom 98% of young people think teeth should be brushed regularly but 40% of them only visit the dentist due to toothache and not for regular check-ups (14). Only students of dental medicine understand the importance of regular check-ups every 6 months (61.9% of them) whereas in the other two groups altogether only three subjects chose this answer.
A high percentage of subjects who brush their teeth twice a day was also obtained in Sarajevo, as many as 79.5% of them (21). It is clear that the subjects’ answers are significantly affected by the so-called social approval factor (22). This factor causes the subjects to state that they brush their teeth twice a day when in fact they only brush once a day or less frequently and the actual frequency of tooth brushing is almost impossible to find out (22). The most socially acceptable answer to the question about the frequency of tooth brushing is 2-3 times a day (23). More than 50% of them are aware that teeth should be brushed 3 times a day or more, but they do not practice that (21).
In all three groups, the DMFT index is higher than the standard for developed European countries. A study in Finland (24), also carried out with students showed that as many as 28% have DMFT 0 whereas in our study only four students (7%) had DMFT 0, all of them students of dental medicine. Oral health is improving in many European countries with the DMFT index lower compared to ten years ago (2.24) but in Croatia this is not the case. According to the available data for Croatia from 1968, 12-year-olds had DMFT 7, which decreased over the years and in 1999 reached 3.5 (11). More recent studies show that the DMFT index is increasing in Croatia (10) and the same results were obtained in this study. Unemployment, inflation, low income and privatisation of the dental practice lead to individual management of oral health services and the main victims of such a situation are children (25).
The comparison between the groups of students of technical sciences and humanities did not reveal great differences. Students of humanities do have lower DMFT index and plaque index but this can be attributed to the fact that the other group (technical sciences) included more males (77%), whereas female students were predominant (60%) in the third group (humanities). Studies which evaluated the correlation between gender and the DMFT index did not reveal a statistically greater correlation but there was a statistically significant link between gender and plaque (26). Conversely, Bego et al., showed a higher DMFT index in women in Croatia compared to men (10).
Students of dental medicine develop a better perception of oral health during their studies, which results in better oral hygiene. Students of dental medicine had less plaque than students of humanities and technical sciences and the difference was statistically significant. Although the dental students had somewhat lower DMFT index values, the difference was not statistically significant and therefore, further research is needed. In all three groups, the DMFT index was higher than in developed European countries. Also, it was higher than ten years ago in Croatia, which points to insufficient preventive measures. The perception of oral health is at a high level but the perception of oral diseases is at a significantly lower level, which is reflected in the high DMFT index values and less frequent visits to the dentist. Owing to the fact that dental students expanded their knowledge on oral hygiene and care, we believe the same could be achieved by better education of patients. Since the attitude toward oral health is positive, such plaque indicators are important as they show the patients which surfaces are inadequately cleaned.