ORIGINAL PAPERS Dent. Med. Probl. 2014, 51, 1, 49 55 ISSN 1644-387X Copyright by Wroclaw Medical University and Polish Dental Society Agnieszka Bruzda-Zwiech 1, 3, A D, Renata Filipińska 1, 3, B, C, E, G, Beata Szydłowska-Walendowska 3, B, Beata Lubowiedzka-Gontarek 3, B, Beata Borowska-Strugińska 2, B, E, Elżbieta Żądzińska 2, E, F, 3, A, E, F Magdalena Wochna-Sobańska Occurrence of Caries in the Permanent Dentition of 8- to 12-Year-Old Children Living in the Lodz Urban Area Występowanie próchnicy w uzębieniu stałym u dzieci w wieku od 8 do 12 lat zamieszkujących w Łodzi 1 Department of Paediatric Dentistry, Medical University of Lodz, Poland 2 Department of Anthropology, Faculty of Biology and Environmental Protection, Medical University of Lodz, Poland 3 Teaching Hospital No. 6, Department of Pedodontics, Dental Institute in Lodz, Poland A research concept and design, B collection and/or assembly of data, C data analysis and interpretation, D writing the article, E critical revision of the article, F final approval of article, G collection of references Abstract Background. Epidemiological studies have demonstrated a decline in caries intensity in schoolchildren, although a simultaneously increasing polarization of the disease has been observed. Objectives. The aim of the study was to determine the appearance of caries in the permanent dentition of 8- to 12-year-old children living in Lodz. Material and Methods. A group of 700 children (385 boys and 315 girls) attending randomly selected public primary schools in Lodz were examined. The children were subdivided into 5 age groups, with an annual breakdown (8, 9, 10, 11 and 12-year-olds). An intra-oral examination was conducted to assess dental caries in permanent dentition. Caries diagnosis was based on the WHO recommendation. The prevalence and intensity of caries, as well as the Significant Caries Index (SiC) were calculated based on the obtained data. Results. The prevalence of caries in the permanent dentition of the examined population was 58%. It was the highest (70%) in children aged 10. The mean DMFT for children 8 years of age was 0.9, and increased to 2.4 in 12-yearolds. In all age groups, DMFT mainly consisted of untreated caries. Also the SiC index increased with children s age (from 2.42 in 8-year-olds to 5.56 in 12-year-olds). Conclusions. The results of the study revealed high SiC values, which indicates the necessity of introducing intensive preventive programs for schoolchildren, especially for the one third with the highest DMFT values, to increase the possibility of achieving the WHO oral health goal for the year 2015 in children aged 12 (Dent. Med. Probl. 2014, 51, 1, 49 55). Key words: dental caries, DMFT, SiC index, school children. Streszczenie Wprowadzenie. Badania epidemiologiczne wskazują na zmniejszenie intensywności próchnicy w wieku szkolnym, jednakże jest obserwowane zjawisko polaryzacji choroby próchnicowej. Cel pracy. Ocena występowania choroby próchnicowej zębów stałych u dzieci w wieku 8 12 lat zamieszkujących w Łodzi. Materiał i metody. Badaniem objęto grupę 700 dzieci (385 chłopców i 315 dziewcząt) uczęszczających do wybranych w drodze losowania publicznych szkół podstawowych w Łodzi. Dzieci podzielono na grupy wiekowe, z przedziałem rocznym: 8, 9, 10, 11 i 12 lat. Stan uzębienia stałego pod kątem występowania próchnicy oceniano według
50 A. Bruzda-Zwiech et al. wytycznych ŚOZ. Na podstawie uzyskanych danych obliczono częstość występowania i intensywność próchnicy oraz istotny wskaźnik próchnicy SiC (Significant Caries Index). Wyniki. Częstość występowania próchnicy w uzębieniu stałym w badanej grupie wynosiła 58%. Najwyższy odsetek dzieci z próchnicą (70%) stwierdzono wśród 10-latków. Intensywność próchnicy (PUW) dla dzieci 8-letnich wynosiła 0,9 i zwiększała się do wartości 2,4 dla badanych 12-latków. O wielkości liczby PUW we wszystkich grupach wiekowych decydowała przede wszystkim liczba zębów z czynną próchnicą. Również wartość wskaźnika SiC wzrastała z wiekiem (od wartości 2,42 do 5,56; odpowiednio u 8- i 12-latków). Wnioski. Wykazane w niniejszym badaniu wysokie wartości wskaźnika SiC wskazują na potrzebę wprowadzania intensywnych programów profilaktyki próchnicy dla dzieci w wieku szkolnym, ze szczególnym uwzględnieniem jednej trzeciej populacji z najwyższymi wartościami PUW, co zwiększyłoby szansę osiągnięcia celu wyznaczonego przez WHO dla dzieci 12-letnich na 2015 r. (Dent. Med. Probl. 2014, 51, 1, 49 55). Słowa kluczowe: próchnica zębów, PUW, wskaźnik SIC, dzieci w wieku szkolnym. Dental caries are considered a major public health problem globally due to their high prevalence and considerable social costs. This is also the most common oral disease in children. The World Health Organization reports that 60 90% schoolchildren worldwide have experienced caries, with the disease being the most prevalent in Asian and Latin American countries [1]. Although its prevalence has declined over the past few decades [2], inequalities in dental caries occurrence exist between countries as well as within populations [3, 4]. The WHO goals set for the year 2000 (50% caries-free 5-year-olds and a maximum mean DMFT score of 3 for 12-year-olds) have already been met in many countries of the Western world [1, 5, 6]. This improvement has been mostly observed in high-income countries [2]. Reduced instances of caries among children and young adults is best documented in the Nordic countries [5, 7]. The mean DMFT for 12-year-olds in 2000 was 1.0 in Sweden and Denmark, and 1.2 and 1.5 in Finland and Norway, respectively [5]. In contrast, the intensity of caries in the Eastern European countries remained high as DMFT for 12-year-olds was 4.4 in Bulgaria, 3.9 in Latvia, 3.6 in Lithuania, and 3.3 in Hungary [8, 9]. The 2000 epidemiological surveys showed that in Poland DMFT for 12-year-olds was higher than 3 (DMFT = 3.8). However, a slow downward trend in occurrences of caries was observed in Polish 12-year-olds from 1999 to 2007 (4.0 to 3.07) [10]. In the Lodz region, DMFT was 2.97 in 2000, and increased to 3.19 in 2003 [11]. Even in countries with low caries indices, the disease has become increasingly polarized, with a high prevalence in a small group of children. According to literature data, 25 30% of children experience 75% of all caries lesions [6]. In 2000, Bratthall proposed the Significant Caries Index (SiC), which corresponds to the mean DMFT for the 1/3 of population with the highest caries levels. It reveals the real epidemiological status and helps to direct the prophylactic strategy to that specific group of children [12]. The goal of WHO is to decrease SiC in 12-year-olds to 3 in 2015 and 1.5 in 2020 [13], while the objective stipulated in the Polish National Health Program for 2007 2015 is to reduce SiC to 4 [10]. One of the major objectives of oral health promotion should be early identification of groups of children at high risk of developing caries and the preparation of a preventive strategy for those children. For that reason, epidemiological surveys continue to be of primary importance, since they can be used to compile oral health data for children over time and identify high-risk groups at different ages [6]. The population of children aged 12 is most often screened for caries experience [10, 11, 14 19], as this age group has been selected by the WHO. Groups of 8 11-year-olds are thus monitored more rarely. This study aimed to assess caries experience (caries prevalence and the DMFT and SiC indices) in 8- to 12-year-old children. Material and Methods An intra-oral examination was conducted in 700 children (385 boys and 315 girls) from randomly selected primary schools in Lodz in the year 2010. The children were subdivided into 5 age groups (8, 9, 10, 11, and 12-year-olds). The structure of the examined population is presented in Table 1. Permanent dentition was clinically examined for caries, and caries diagnosis was based on the WHO recommendation. The caries prevalence and intensity (DMFT the total number of decayed, missing due to caries and filled permanent teeth) were calculated based on the obtained data. Also the Significant Caries Index (SiC) was computed for the one third of children with the highest DMFT values. The data was statistically analyzed using the Mann-Whitney and chi-squared tests. Statistical significance was inferred if p < 0.05. The study was performed with the consent of the Ethical Committee of the Medical University in Lodz (No. RNN/63/08/ KE).
Caries Experience in the Permanent Dentition of 8- to 12-Year-Old Children 51 Table 1. The structure of the examined population Tabela 1. Struktura badanej populacji Age (in years) Boys (Chłopcy) Girls (Dziewczęta) Total (Razem) (Wiek w latach) n % n % n % 8 115 57.5 85 42.5 200 100 9 67 47.86 73 52.14 140 100 10 59 53.64 51 46.36 110 100 11 86 59.72 58 40.28 144 100 12 58 52.73 48 47.27 106 100 Total 385 55 315 45 700 100 Results Figure 1 presents the prevalence of caries (for permanent dentition) in the examined group in relation to gender and age. More than half (58%) of the entire group of examined children had caries-free permanent dentition. In 8- to 10-year-old children the prevalence of caries increased with age and was 43% in 8-year-olds, 57.14% in 9-yearolds, and 70% in 10-year-olds, while 63.89%, and 66.98% of 11- and 12-year-old children were affected by caries, respectively. Statistical analysis showed that the frequency of caries in the whole study population and for particular age groups was independent of gender, with the exception of 12-year-old children. At the age of 12, boys had a significantly higher prevalence of caries than girls (χ 2 = 6.51, p = 0.01). Data on the mean DMFT and its components in relation to children s age and gender are presented in Table 2. Caries intensity in permanent teeth increased with children s age from 0.9 in 8-year-olds to 2.4 in 12-year-olds. The mean DM- FT for the whole examined population was equal to 1.56, and mainly consisted of untreated caries (DT = 10.9). The values of the FT component were much lower, with the mean value being 0.34 (ranging from 0.24 to 0.99 in 8- and 12-year-olds, respectively). There was no relationship between caries intensity (mean DMFT, DT, and MT components) and gender, in the whole population and in any age subgroup. However, a significantly higher FT value was found in 12-year-old boys than girls (FT = 1.05 vs. FT = 0.73, Z = 1.98, p = 0.046). In the subgroup of children aged 12, boys also exhibited a higher decay component and the DMFT value than girls (DT = 1.8 vs. DT = 1.44 and DM- FT = 2.57 vs. DMFT = 2.13), although the differences were not significant (p > 0.05). Figure 2 presents the SiC values calculated for the one third of children with the highest DMFT values, according to sex and age group. The SiC Fig. 1. Prevalence of caries in permanent dentition (%) in examined group as related to gender and age * statistically significant χ 2 = 6.513; p = 0.010607 Ryc. 1. Frekwencja próchnicy w zębach stałych w badanej populacji z uwzględnieniem podziału na wiek i płeć * istotność statystyczna χ 2 = 6,513; p = 0,010607
52 A. Bruzda-Zwiech et al. Table 2. Mean DMFT score and DT, MT, FT components in examined population as related to age and gender Tabela 2. Średnia liczba PUW i jej składowe P, U, W w badanej populacji z uwzględnieniem podziału na wiek i płeć Age in years Boys (Chłopcy) Girls (Dziewczęta) Total (Razem) (Wiek w latach) DT MT FT DMFT DT MT FT DMFT DT MT FT DMFT 8 0,6 0.0 0.2 0.8 0.76 0.0 0.28 1.05 0.67 0.0 0.24 0.9 9 1.06 0.0 0.27 1.31 0.96 0.03 0.7 1.62 1.01 0.01 0.49 1.47 10 1.35 0.00 1.42 1.78 1.46 0.0 0.56 1.98 1.4 0.00 0.49 1.87 11 1.33 0.00 0.68 1.77 0.9 0.03 0.72 1.62 1.14 0.01 0.7 1.7 12 1.8 0.06 1.05* 2.57 1.44 0.0 0.73* 2.13 1.56 0.03 0.99 2.4 8 12 0.13 0.008 0.47 1.52 1.04 0.01 0.57 1.6 1.09 0.01 0.52 1.56 * statistically significant Z = 1.98982; p = 0.046612. * istotność statystyczna Z = 1,98982; p = 0,046612. Fig. 2. SiC index in examined population as related to age and gender Ryc. 2. Wskaźnik SiC w badanej populacji z uwzględnieniem podziału na wiek i płeć values ranged from 2.42 in children aged 8 to 5.56 in 12-year-olds. No significant gender-dependent differences in the indices were found. Discussion The results of the study confirm the findings of previous epidemiological surveys [11, 17, 19, 20] regarding the high prevalence and intensity of caries in primary school children in Poland. The prevalence and intensity of caries between the ages of 8 and 12 years steadily increased as the children grew, which remains in accord with the results reported by other authors [21 23]. The prevalence of caries in our study was 43% in 8-year-old children, while in the UK it was 19% in this age group (in 2005) [22]. Although the caries prevalence for 12-year-olds (66.9%) was lower than that for the general Polish population living in urban areas in 2007 (77.7%) [10], and also lower than that for children living in Lodz in 2003 (74.8%) [11], it was still higher than in many European countries, e.g., 52.9% in Portugal (1999), 50% in Germany (2003), 46% in Italy (2004), 43% in the UK (2005), 39% in Sweden (2008), and 31% in Denmark (2009) [22 26]. The mean DMFT value for 9- to 11-year-olds ranged from 1.31 to 1.77, and was lower than that reported in the 2009 study by Warsz and Rudnicka-Siwek, in which the mean DMFT value calculated for the group of 9 11-year-old children from Lublin was 4.26 [20]. Also caries intensity for 10-year-old children was lower in our study than in the 2004 epidemiological survey in Lublin (1.87 vs. 3.1) [27]. Caries intensity (DMFT) for children aged 12 was also lower than that for the general Polish population in 2007 (3.07), as well as for the urban areas of Silesia (4.21) and Podlasie (4.42) (in 2010 and in 2005, respectively), although
Caries Experience in the Permanent Dentition of 8- to 12-Year-Old Children 53 higher than that in Poznań in 2010 (1.59) [10, 18, 28]. When comparing DMFT values for children aged 12 with previous data from the Lodz region, a slight downward trend can be observed, considering the years 2000 and 2003 (with a DMFT for the urban area of 2.74 and 2.97, respectively) [11]. Also other epidemiological studies confirm a slow downward trend in caries intensity from 1999 to 2007 (from 4.0 to 3.07 for the general Polish population and from 4.0 to 2.8 in the urban population), albeit with an outlier in 2003 (3.8) [10]. According to the literature, the decrease in caries intensity and the continually growing number of cariesfree individuals can be associated with changing lifestyles, improved oral hygiene, the use of fluoridated toothpaste, the topical application of fluorides, and the prophylactic programs introduced in schools [9]. Nevertheless, the epidemiological surveys conducted within the last ten years show that in many European countries, especially in those which have reached the WHO goal for 2000, mean DMFT values remain lower than those obtained in our study for 11-year-olds, e.g., 0.5 in Germany (2004), as well as for 12-year-olds, e.g., 0.87 in Germany (2004), 0.9 in Sweden (2005), 0.6 in Denmark (2009), 1.2 in Finland (2003), 1.4 in Norway (2008), and 1.5 in Portugal (2003) [5, 23, 24, 26]. Moreover, our study reveals that untreated caries predominantly account for the DMFT score, which indicates neglected oral health in 8 12-year-old children living in Lodz, as well as a need for dental care, and proves that occurrences of dental caries are not under control yet. This is also in accord with the findings of other authors [11, 20]. According to Baelum et al., untreated dental caries remain a global public health problem, especially in low- and middle-income countries [7]. In our survey, the number of filled teeth (0.99) in children aged 12 was even lower than in 2003 (1.02), and the number of teeth with active caries decreased (1.56 vs. 2.1) [11]. In children from the urban areas of Podlasie the FT component was 3 times higher (3.37), but still every child had statistically almost one and half teeth to be treated [18]. In the 2007 national survey, the mean DT value for the general population of Polish children aged 12 was lower than the mean FT value (0.99 vs. 1.73), which may indicate a slight improvement of the effectiveness of dental care, although the treatment index was still unsatisfactory (0.64) [10]. Caries intensity in permanent teeth ranged from 0.9 in 8-year-olds to 2.4 in 12-year-olds, while the mean SiC index was more than twice higher. The results of other epidemiological studies confirm the polarization of this disease in Polish schoolchildren. In the Lublin region, the SiC index for the population of children aged 10 was almost twice higher than the mean DMFT (5.5 vs. 3.1) [27], which was also the case in the urban areas of Silesia (6.59 vs. 3.07) and Podlasie (8.45 vs. 4.42) for children aged 12 [18, 19]. In the Lodz region, SiC for 12-year-olds in 2003 was also more than twice higher than the DMFT score (6.89 vs. 3.19) [17]. Analysis of SiC values for 11- and 12-year-old children revealed that they were higher than in Western European countries. In Germany, SiC for children aged 11 (without immigration experience) was 1.5. Germany, Austria, Denmark and Sweden have already attained the WHO goal for 2015 (with SiC for 12-year-olds being 2.45, 2.79, 1.9 and 2.5, respectively); also SiC for Italy (3.1), as well as England and France (3.2) is very close to 3 [5, 24, 29]. On the other hand, in 2000 in Poland SiC for 12-year-olds amounted to 7.0 [15]. In our study, SiC was 5.56 and was lower than that in the urban areas of the Lodz region in 2003 (6.81), although it still remained higher than in 2000 (5.2) [11, 17]. The mean SiC was very close to the value achieved in 2004 in the Lodz region (5.72) [16], which suggests that despite some decrease in the caries intensity of the one third of children with the highest DMFT scores, the rate of positive changes has been quite low. When analyzing occurrences of caries in relation to gender, we noticed that boys aged 12 years had a significantly higher prevalence of caries than girls, but no differences were found in the other age groups. Similarly to the results of other authors [19, 20] the intensity of caries (DMFT and SiC) in our study group was independent of gender. In contrast, in the 2003 study by Rybarczyk et al. [17] conducted in the region of Lodz, the SiC index was significantly higher (7.64) in girls than in boys (6.09), while in 2004 no significant differences between SiC values for girls and boys were found (5.78 and 5.65, respectively) [16]. The results of our study revealed high SiC values for 8- to 12-year-old children, which indicates the necessity to introduce intensive prevention programs for primary school children in Lodz, especially for the one third with the highest DMFT values. The programs should be adjusted to the individual needs of children with high caries intensity, as was proposed by Burt [30], and include the application of professional fluoride gels and varnishes, as well as fissure sealing in molar teeth. The introduction of such programs and effective dental treatment provided to children in the younger age groups may increase the likelihood of attaining the goals of the National Health Program formulated for Poland for 2007 2015, and possibly the WHO oral health goal for children aged 12 in the year 2015.
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Caries Experience in the Permanent Dentition of 8- to 12-Year-Old Children 55 Address for correspondence: Agnieszka Bruzda-Zwiech Department of Paediatric Dentistry Medical University of Lodz Pomorska 251 92-213 Lodz Poland Tel./fax.: +48 42 675 75 16 E-mail: agnieszka.bruzda-zwiech@umed.lodz.pl Received: 18.11.2013 Revised: 21.01.2014 Accepted: 23.01.2014 Praca wpłynęła do Redakcji: 18.11.2013 r. Po recenzji: 21.01.2014 r. Zaakceptowano do druku: 23.01.2014 r.