*Anna Turska-Szybka1, Iwona Soika1, Małgorzata Kalita1, Dariusz Gozdowski2, Dorota Olczak-Kowalczyk1
Dentition in children attending secondary school based on 2015 Monitoring of Oral Health and its Determinants in Mazovia Province. Part I. Dental caries
Stan uzębienia uczniów szkół gimnazjalnych na podstawie Monitoringu Stanu Zdrowia Jamy Ustnej i Jego Uwarunkowań w 2015 roku w województwie mazowieckim. Część I. Choroba próchnicowa
1Department of Paediatric Dentistry, Medical University of Warsaw
Head of Department: Professor Dorota Olczak-Kowalczyk, MD, PhD
2Department of Experimental Design and Bioinformatics, Department of Agriculture and Biology, Warsaw University of Life Sciences
Head of Department: Professor Wiesław Mądry, PhD
Wstęp. Wyniki dotychczasowych badań stanu zdrowia jamy ustnej wskazują na bardzo zły stan uzębienia w populacji młodzieży szkolnej w Polsce. W badaniach z roku 2008 wykazano, że w populacji 15-latków odsetek młodzieży z chorobą próchnicową był bliski 94%, a z 2011 roku, że zaledwie 8% badanych było wolnych od próchnicy. Z raportu NIK z 2013 roku wynika, że stan zdrowia jamy ustnej znacznie odbiega od standardów europejskich. Monitoring Stanu Zdrowia Jamy Ustnej i Jego Uwarunkowań pozwala na określenie nasilenia próchnicy zębów, odsetka młodzieży z zębami usuniętymi z powodu próchnicy, wartości wskaźnika leczenia zachowawczego próchnicy i wielkości potrzeb leczniczych, a także odsetka objętych postępowaniem profilaktycznym.
Cel pracy. Ocena stanu uzębienia uczniów szkół gimnazjalnych w województwie mazowieckim na podstawie badań epidemiologicznych przeprowadzonych w 2015 roku.
Materiał i metody. Badaniem objęto grupę 215 osób 15-letnich z województwa mazowieckiego. Badania kliniczne przeprowadzono zgodnie z wytycznymi WHO. Obliczono frekwencję i poziom próchnicy u młodzieży, wartości D3MFT oraz ich składowych, wskaźnik leczenia zachowawczego, istotny wskaźnik poziomu próchnicy SiC. Wyniki badań poddano analizie statystycznej z wykorzystaniem testu t oraz testu chi-kwadrat.
Wyniki. Frekwencja próchnicy w badanej grupie młodzieży wyniosła 94,9%, zarówno u chłopców, jak i dziewcząt, oraz była wyższa w środowisku wiejskim (97%) w porównaniu do miejskiego (94,3%). Średnia wartość D3MFT wyniosła 6,07 ± 3,53, natomiast średnia wartość wskaźnika SiC 9,94 ± 2,29. Wskaźnik leczenia próchnicy w tej grupie wiekowej kształtował się na poziomie 0,51 ± 0,36. Brak potrzeb leczenia zachowawczego i chirurgicznego stwierdzono jedynie u 3,3%, natomiast profilaktyka próchnicy potrzebna była aż u 76,7%.
Wnioski. Na podstawie przeprowadzonych badań stwierdzono:
1. Wysoką frekwencję próchnicy wśród 15-letniej młodzieży gimnazjalnej województwa mazowieckiego.
2. Wysoki poziom choroby próchnicowej wśród badanych.
3. Wskaźnik leczenia choroby próchnicowej wskazuje na połowę wyleczonych zębów.
4. Istnieje konieczność poprawy efektywności opieki stomatologicznej w województwie mazowieckim poprzez działania profilaktyczne, edukacyjne i lecznicze.
Introduction. Recent studies on oral health indicate very poor dental condition in the population of school children in Poland. A 2008 study showed that the proportion of patients with dental caries accounted for nearly 94% of 15-year olds. Another study (2011) demonstrated that only 8% of subjects were caries-free. According to 2013 NIK report, the oral health is far from the European standards. A study conducted in 2011 showed that nearly 92% of 15-year-old children had dental decay, whereas only 6% of the evaluated children were free of caries in 2008. The Monitoring of Oral Health and its Determinants allows to assess the severity of dental caries, the percentage of adolescents with teeth extracted due to dental caries, the index of conservative caries treatment and the size of treatment needs as well as the percentage of individuals receiving prophylaxis.
Aim. Dental assessment of children attending secondary schools in Mazovia Province based on epidemiological research conducted in 2015.
Material and methods. A total of 215 15-year-old children from Mazovia Province were included in the study. Clinical evaluation was performed in accordance with the WHO guidelines. The incidence and the level of dental caries, D3MFT and its components, the index of conservative treatment and the significant caries index (SiC index) were assessed in adolescents. The results were analysed statistically using the T-test and chi-square test.
Results. The incidence of tooth decay was 94.9% in the study population (in both boys and girls), and was higher in rural (97%) compared to urban areas (94.3%). The mean D3MFT was 6.07 ± 3.53, and the mean SiC was 9.94 ± 2.29. The index of caries treatment was 0.51 ± 0.36 in this age group. No need of conservative or surgical treatment was found in only 3.3% of subjects, while 76.7% of subjects required only caries prevention.
Conclusions. The following was concluded based on the conducted research:
1. The incidence of dental caries among 15-year-old adolescents attending secondary schools in Mazovia Province is high.
2. The level of dental caries in the subjects is high.
3. The treatment index indicates that 50% of teeth are repaired.
4. There is a need to improve the efficiency of dental care in Mazovia Province through preventive, educational and therapeutic approaches.
The analysis of the dynamics of tooth decay prevalence demonstrated that dental caries is listed next to ischemic heart disease, cancer, type 2 diabetes or allergies, as a serious disease of modern society, which is strongly related to lifestyle on one hand, as well as systemic and environmental factors, on the other hand. Recent studies on oral health indicate very poor dental condition in the population of adolescents in Poland. A 2008 study showed that the proportion of patients with dental caries accounted for nearly 94% of 15-year olds. Another study (2011) demonstrated that only 8% of subjects were caries-free. According to 2013 NIK report, the oral health is far from the European standards (1, 2). High caries indices are reported, among others, in Mazovia Province.
Evaluation of adolescents is performed at three-year intervals due to the primary focus on the population of children and adolescents, as in accordance with the principles for oral health monitoring adopted by the World Health Organization. The National Monitoring of Oral Health and its Determinants, which has been systematically implemented since 1997, allows to assess the severity of dental caries in adolescents, the percentage of adolescents with teeth extracted due to dental caries, the index of conservative treatment of dental caries and the size of treatment needs as well as the percentage of individuals receiving prophylaxis (including fissure sealing). The results of the research allow to address the effectiveness of the current dental care system and point to the intensification of preventive and therapeutic measures to improve health and the quality of life in these patients. The collected data has contributed significantly to the improvement in oral health in many countries where it was used, e.g. for dental care planning and the development of intervention programs.
The aim of the study was to assess dental status in children attending secondary schools in Mazovia Province based on 2015 National Monitoring of Oral Health and its Determinants.
Material and methods
The study included a group of 15-year-old adolescents from Mazovia Province, selected based on stratified sampling.
The study was conducted as a part of 2015 National Monitoring of Oral Health and its Determinants (Ministry of Health), based on the WHO classification criteria for clinical conditions, under similar conditions, using artificial light, a flat mirror and a calibrated WHO-621 periodontal probe and by previously trained personnel (3). The incidence and the level of dental caries in adolescents, D3MFT index and its components, the percentage of subjects with D3MFT index components = 0, 1-3 and ≥ 4, Significant Caries Index (SiC) indicating 1/3 of patients with the highest number of carious teeth, as well as the index of conservative treatment were calculated.
Results are presented as mean values and standard deviations or as the number or percentage of patients. Statistical analysis was performed using t-test for comparison between two groups (sexes or places of residence) and chi-square test for comparison of fractions. A p < 0.05 was accepted as statistically significant. Statistica 12 was used for statistical analysis.
The study was approved by the Bioethics Committee of the Medical University of Warsaw (Approval No KB/217/2015 dated 3rd November 2015). Written consent of parents/legal guardians was obtained prior to study. Lack of consent to participate in the study was an exclusion criterion.
A total of 215 15-year-old children attending secondary schools – 140 (65.1%) urban residents and 75 (34.9%) rural residents, including 136 (63.3%) girls and 79 (36.7%) boys, participated in the study. The incidence of tooth decay was 94.9% in both girls and boys and was higher in rural (97%) compared to urban areas (94.3%). There were no statistically significant differences between the values of D3MFT index for different places of residence. The average number of teeth present in the assessed secondary school students was 27.79 ± 0.65 and was comparable for both girls (27.76 ± 0.67) and boys (27.85 ± 0.62) as well as for different places of residence (city – 27.89 ± 0.48, rural areas – 27.60 ± 0.87).
Mean values of D3MFT index and components are shown in table 1. Comparison of the two different places of residence demonstrated higher value of the D3MFT index and its components in the group of rural adolescents, with statistically significant difference for D3T component. There were no statistically significant differences between sexes.
Tab. 1. Mean values of D3MFT and D3MFT components
|D3MFT||5.81 ± 3.47||6.55 ± 3.63||6.12 ± 3.43||5.99 ± 3.73||6.07 ± 3.53|
|D3T||2.87 ± 2.84||3.00 ± 2.92||2.79 ± 2.81||3.14 ± 2.95||2.92 ± 2.86|
|MT||0.03 ± 0.21||0.17 ± 0.55||0.09 ± 0.41||0.06 ± 0.29||0.08 ± 0.37|
|FT||2.91 ± 2.77||3.37 ± 3.3||3.24 ± 2.97||2.78 ± 2.96||3.07 ± 2.97|
|p for D3T||0.754||0.385||< 0.001*|
|p for MT||0.006*||0.637||0.648|
|p for FT||0.281||0.276||0.039*|
*statistically significant (p < 0.05)
D3T – the mean number of decayed permanent teeth; MT – the mean number of missing permanent teeth; FT – the mean number of filled permanent teeth
Table 2 shows the number and the percentage of children with at least one carious tooth, tooth lost due to caries or for other reasons as well as a filled tooth.
Tab. 2. The number and the percentage of children with at least one decayed tooth (D3T ≥ 1), tooth lost due to caries – code 4 (MT ≥ 1), tooth lost due to other reasons – code 5 (MT ≥ 1) and filled tooth (FT ≥ 1)
|D3T ≥ 1||n||106||57||100||63||163|
|MT ≥ 1||n||3||9||8||4||12|
|MT ≥ 1||p||0.003*||0.801|| |
|Other cause||p||0.652||0.0279|| |
|FT ≥ 1||n||109||55||106||58||164|
*statistically significant (p < 0.05)
Mean SiC in the study group was 9.94 ± 2.29. There were statistically significant differences between the two places of residence. The mean value of the index was higher in rural (10.56 ± 2.29) compared to urban areas (9.62 ± 2.25) and among boys (10.19 ± 2.42) compared to girls (9.87 ± 2.22). There were no statistically significant differences between sex groups. Mean D3MFT for the remaining 2/3 of subjects was 2.69 ± 1.65 and was higher in rural (4.54 ± 2.23) compared to urban areas (3.89 ± 2.12) as well as among girls (4.26 ± 2.16) compared to boys (3.92 ± 2.21) (statistically insignificant differences).
The mean number of sealed molars was 0.56 ± 1.18 (tab. 3), which represents only 7.1% of all molars present in the oral cavity. The mean index of conservative treatment of dental caries was 0.51 ± 0.36 and was slightly higher among girls (0.55 ± 0.36) and rural residents (0.53 ± 0.38) compared to boys (0.53 ± 0.38) and urban adolescents (0.51 ± 0.36). The differences were statistically insignificant. No need of conservative or surgical treatment was found in only 3.3% of subjects, and 76.7% of subjects required only caries prevention, including fissure sealing in second molars in 31.2% (tab. 4).
Tab. 3. The average number of molars present in the oral cavity (M) and filled molars (FM) (code 6)
|Mean ± SD|
|M||7.96 ± 0.22||7.73 ± 0.74||7.88 ± 0.46||7.89 ± 0,53||7.88 ± 0.48|
|FM||0.67 ± 1.32||0.35 ± 0.81||0.46 ± 1.05||0.72 ± 1.36||0.56 ± 1.18|
|p (M)||0.001*||0.957|| |
|p (FM)||0.054||0.121|| |
*statistically significant (p < 0.05)
Tab. 4. The percentage of patients aged 15 years in relation to the identified needs for conservative and surgical treatment
| ||No needs||Caries prevention only||Fissure sealant||Filling for 1 surface cavity||Filling for more than 1 surface cavity||Pulp treatment||Extraction||Other|
|Boys||1 (1.3%)||61 (77.2%)||25 (31.6%)||60 (75.9%)||27 (34.2%)||4 (5.1%)||2 (2.5%)||0 (0%)|
|Girls||6 (4.4%)||104 (76.5%)||42 (30.9%)||93 (68.4%)||45 (33.1%)||6 (4.4%)||6 (4.4%)||3 (2.2%)|
|Urban||3 (2.1%)||109 (77.9%)||51 (36.4%)||99 (70.7%)||48 (34.3%)||5 (3.6%)||4 (2.9%)||0 (0%)|
|Rural||4 (5.3%)||56 (74.7%)||16 (21.3%)||54 (72%)||24 (32%)||5 (6.7%)||4 (5.3%)||3 (4%)|
|Total||7 (3.3%)||165 (76.7%)||67 (31.2%)||153 (71.2%)||72 (33.5%)||10 (4.7%)||8 (3.7%)||3 (1.4%)|
*statistically significant (p < 0.05)
G – girls; B – boys; U– urban; R– rural
For years, a significant increase in the level of caries has been observed among adolescents in epidemiological research. The first research conducted as a part of the Monitoring of Oral Health and its Determinants in Mazovia Province, which included 15-year-old students, was conducted in 2005, and was later (2008) continued across many provinces in the country (1).
The current research showed that the incidence of dental caries is 94.9%, with higher proportions of caries-free subjects in urban rather than rural areas. The oral health of 15-year-old adolescents has not improved. The percentage of caries-free individuals (5.1%) was lower compared to previous studies. The lowest incidence of dental caries in Mazovia Province was reported in 2003 (90.5%), and it increased reaching 95.9% in 2008, followed by 96.8% in 2011 (1, 2, 4-6). Similar, high values were obtained by researchers from Małopolska Province between 2002 and 2003 (95.3%) and currently (92.3%) (7) as well as by a team from Łódź Province (93.8%) in 2011 (1). National data showed a similar tendency (91.8%) in 2011 (1). A research conducted in adolescents from Wielkopolska Province showed caries incidence of 92.5% in 2008, which decreased to 88% in 2011 (8).
Sikorska-Jaroszyńska et al. (9), Hajto-Bryk (10), Mielnik--Błaszczak et al. (11) found that the incidence of caries was 100% in 15-year-olds (11). In Lublin Province, the incidence of dental caries in adolescents aged 15-17 years, who did not receive regular caries prophylaxis, was 99.7% (12). Małkiewicz and Kępa found that the incidence of dental caries in 15-year old adolescents from Mazovia Province was lower in 2003 than currently, i.e. 90.5% (13). Similarly, lower incidence was reported by Molęda-Ciszewska (89.43%) (14). The lowest incidence was reported in 15-year-olds in India and Macedonia, with 25.7% of caries-free adolescents from India and 18.7% from Macedonia (15). Dental caries was reported in 41.4% of 12-15-year-olds from India, with statistically significantly higher percentage in public schools (51.7%) compared to private institutions (28.9%) (16). The incidence of dental caries in 15-year-olds from Ambala (India) was 46.5% (17). Dental caries was reported in more than half of 15-year-olds (51.9%) from the Netherlands (18) and 57% in Switzerland (19) as well as 64% of Danes (20) and 43.6% of Spanish adolescents (21), all of which represent lower reported incidence of dental caries in Europe. Higher incidence of dental caries among 15-year-olds was reported in Thailand – 68.6% (22), Northern India – 86.16% (23), Iran – 75.5% (24), Brazil – 87.8% (25) and Russia – 91.8% (26).
The level of dental caries has currently reached 6.07 in Mazovia Province. Lower index of dental caries in permanent teeth was reported in 2003, 2005 and 2008 (5.86 as well as 4.8 and 5.69, respectively), whereas higher (8.46) values were observed in 2011 (4-6, 13, 27). Studies among 15-year-olds in Mazovia Province in 2002 showed that the mean DMFT was 4.09 in a large city and 5.96 in a smaller town (13). The lowest mean DMFT was shown in adolescents from Andhra Pradesh (India), i.e. 0.6 (16), followed by Spain – 1.08 (21), Ambala (India) – 1.26 (17), India and Switzerland – 1.72 (15, 19), Thailand – 2.4 (22), Iran – 2.66 (24), Macedonia – 3.43 (15) and Russia – 4.92 (26). Another study, which was conducted among Icelandic children aged 15 years showed that the DMFT was 2.78, but it increased to 4.25 after bitewing radiograph analysis (28). The mean DMFT in Northern India was 4.21, while DMFS – 5.38 (23). Ambarkova et al. showed statistically significant differences between sex groups (6.65 for girls and 5.04 for boys) (29). The trend in the distribution of dental caries in our study, where the FT component representing the mean number of filled teeth contributed most to the caries index (3.07) and was statistically significantly higher compared to DT (2.92), is noticeable. This would indicate improved dental care in adolescents from Mazovia Province. However, the mean number of permanent carious teeth gradually increased over years from 2.03 in 2008, 2.67 in 2011 up to 2.92 in 2015 (4-6). The DT component was 1.67 ± 2.22 in India (15), 1.47 ± 2.18 in Macedonia (15), 2.83 ± 2.74 in the east region of Macedonia (29), 0.86 in Valencia (Spain) (21) and the lowest DT component.
The mean number of extracted teeth (0.08) is currently 4 times lower than in 2008 (0.22) and significantly lower than in 2011 (0.12) (4, 5). The percentage of adolescents with at least one tooth extracted due to caries was 5.6% and significantly decreased compared to 2008 (10.8%) (4) and 2011 (9.4%) (5), which may indicate the implementation of endodontic treatment of molars in secondary school students. The mean number of missing (extracted) teeth (the MT component) was 0.17 in 2008 (5) and 0.16 in 2011 (4) in Polish 15-year olds. The study showed a statistically significant difference in MT component between urban (0.03) and rural (0.17) areas. Poorer dental health in rural areas compared to cities has been observed for a long time also in other provinces, which is probably due to the limited access to dental care in smaller towns (1, 13, 27). The MT component was 0.30 ± 0.75 in Macedonia, 0.045 ± 0.34 in India (15), and 0.02 in Valencia (Spain) (21). The FT component (3.07) in Mazovia Province decreased compared to the previous monitoring (4.45) and was comparable with the value reported in 2008 (3.43) and lower than the national average in 2008 (3.76) (5) and 2011 (3.29) (4). The FT component was significantly higher in Macedonia (1.67 ± 2.42) compared to India (0.02 ± 0.09) (15) and in the east region of Macedonia (2.53 ± 3.03) (29), and very low in Valencia (0.77) (21).
At present, the mean SiC value in Mazovia Province is 9.94 ± 2.29, which is lower than the national average in 2008 (10.08) (5) and 2011 (10.80) (4). The mean value of this index was statistically significantly higher in rural areas compared to cities. Nationwide research conducted in 2011 in 15-year-olds showed that the SiC was 10.82 in urban residents and 10.77 in rural residents (5). The mean SiC value in Switzerland was only 4.39 (19), while in Macedonia it was similar to the value obtained in Mazovia Province (10.22) (29).
The low treatment index in dental evaluation indicates that only slightly more than half of decayed teeth were filled. The results for Mazovia Province correlate with those in 2011 (0.53), those obtained by Małkiewicz i Kępa (0.53) as well as the level of the national average value in 2011 (0.55) (5) and are lower than in 2008 (0.63) (4, 13, 27).
In our study, one in three secondary school students (31.1%) had a sealed molar, an average of 0.56 ± 1.18 of tooth, which accounts for 7.15% of all molars. In 2008, 13.1% of 15-year-olds had an average of 1.63 sealed teeth (4). The nationwide percentage of 15-year-old secondary school students with sealed teeth was lower in 2011 and was equal to 19.7% (2). No need of conservative and surgical treatment was observed in only 3.3%, while 76.7% of subjects required caries prevention only. One in three 15-year-olds required one surface filling, whereas treatment of pulp was needed in 4.7% of subjects, and tooth extraction was needed in 3.7% of subjects. According to data obtained during previous monitoring in Mazovia Province, pulp treatment was needed in 3.7% of subjects, extraction was needed in 6.4% compared to similar nationwide data (3.2 and 6%, respectively). In 2008 in Mazovia Province, the percentage of teeth requiring pulp treatment was lower (2.5%), but the percentage of teeth intended for extraction was significantly higher (11.5%) (4).
The conducted study revealed high incidence of dental caries among 15-year-old adolescents attending secondary schools in Mazovia Province. A very high level of caries was observed in the subjects. The index of caries treatment indicated that 50% of teeth were repaired. There is a need to improve the efficiency of dental care in Mazovia Province through preventive, educational and therapeutic approaches.
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