International Dental Journal (2003) 53, 289–298

Oral knowledge, attitudes and behaviour of children and adolescents in China

Ling Zhu Beijing, China Poul Erik Petersen Geneva, Switzerland Hong-Ying Wang, Jin-You Bian and Bo-Xue Zhang Beijing, China

Objectives: A national representative study to describe oral health During the past two decades, many behaviour, illness behaviour, oral health knowledge and attitudes among industrialised countries have expe- 12-year-old and 18-year-old Chinese, to analyse the oral health behaviour rienced a dramatic decline in dental profile of the two age groups in relation to province and urbanisation, and to caries prevalence of children and assess the relative effect of socio-behavioural risk factors on dental caries adolescents1–4. The reasons for the experience. Methods: The total number of 4,400 of each age group were improved oral health are complex selected and data were collected by clinical examinations (WHO criteria) but may involve a more sensible and self-administered structured questionnaires. Results: 44.4% of the approach to sugar consumption, respondents brushed their teeth at least twice a day but only 17% used improved oral practices, fluoridated . Subjects who saw a during the previous 12 in toothpaste, topical fluo- months or two years were 31.3% and 35.3% for 12-year-olds and 22.5% ride application, effective use of and 20.2% for 18-year-olds, respectively. Nearly one third (29%) of 12 year- oral health services and establish- olds and 40.5% of 18-year-olds would visit a dentist in case of signs of ment of school-based preventive caries but only when in pain. Nearly half of the participants (47.2%) had programmes5–10. In parallel with the never received any oral health care instruction. Significant variations in oral changing oral patterns there health practices were found according to province and regular dental care have been significant improvements habits were more frequent in urban than in rural areas. The risk of dental in oral health awareness, dental caries was high in the case of frequent consumption of sweets and dental knowledge and attitudes of chil- caries risk was low for participants with use of fluoridated toothpaste. 11–13 Conclusion: Systematic community-oriented oral dren and parents . Conversely, programmes are needed to target lifestyles and the needs of children, increasing levels of dental caries particularly for those living in rural areas. A prevention-oriented oral health have been observed in several care policy would seem more advantageous than the present curative developing countries, especially for approach. those countries where preventive programmes have not been imple- Key words: , oral health knowledge, oral health behaviour, oral mented14–16. health habits In China, surveys of oral health status have been conducted in different provinces or local communities. Some variation in the occurrence of oral disease is found, for example in recent studies the mean dental caries experience of 12-year-olds was reported at 0.4– Correspondence to: Dr. Poul Erik Petersen, World Health Organization, Non-Communica- 17–22 ble Disease Prevention and Health Promotion, Oral Health Programme, 20 Avenue Appia, 1.9 DMFT . The analysis of oral CH-1211 Geneva 27, Switzerland. Email: [email protected] health habits, knowledge and atti-

© 2003 FDI/World Dental Press 0020-6539/03/05289-10 290 tudes of children was initiated in stratified cluster random sampling then transferred to the National the late 1980s and these studies were involving 11 provinces and within Committee for Oral Health in carried out in some provinces each province the total number of Beijing for central data analysis. The among urban children19,22. How- 400 subjects of the WHO standard national data file was constructed ever, such oral health behaviour ages was identified from randomly by the Department for Epidemi- data of children are scarce for rural selected schools. The schools were ology, Peking University, Faculty population groups. Since the intro- chosen from at least three loca- of Medical Science, Beijing. The duction of the national ‘Love Teeth tions in each province and district data were finally converted for Day’ campaigns in 1988, a number and in urban and rural areas, analysis by means of the Statistical of projects have respectively. For the present study, Package for the Social Sciences been implemented at province and the survey comprised 8,800 partici- (SPSS 10.0) in the WHO Collabo- community-levels throughout the pants, i.e. 4,400 in each age group rating Centre for Community Oral country. and the final sample was balanced Health Programmes and Research, National oral health behaviour by gender and urbanisation. University of Copenhagen. Bivariate data are needed for national plan- Oral epidemiological data were and multivariate analyses of the data ning and evaluation of health collected by clinical examinations on oral health knowledge, attitudes promotion programmes and system- according to WHO methodology and behaviour were based on atic analysis of oral health behaviour and criteria and all examiners were frequency distributions. The Chi- may help the specification of oral trained and calibrated to accept- square test was used in the statistical health messages as well as devel- able standard17,24. Examinations evaluation of the bivariate frequency opment of behaviour modification were carried out in daylight. In distributions. For the assessment of strategies relevant to China. There- addition, structured questionnaires the relative effect of behavioural fore, the second national oral health were used for self-administration factors on dental caries experience, survey was designed in order to whereby the participants were multiple dummy regression analy- provide nation-wide information asked about demographic back- sis and logistic for the analysis of both oral health ground, oral health knowledge and were performed. Dental caries status and oral health knowledge, attitudes, self-care practices, and experience index (DMFT) was the attitudes and behaviour of the utilisation of dental services. The dependent variable in the dummy Chinese population of ages 12, 18, questionnaires were filled out by regression analyses. In the logistic 35–44, and 65–74 years. The the respondents themselves in the regression model the dependent results from the clinical investiga- classroom and the data collection variable was represented by the tion of oral health conditions have was supervised by survey staff dichotomous presence or absence been described separately17,23. The specially trained for this activity. of caries (i.e. DMFT=1 or more, purpose of this report is to The supervisors had at least tertiary or DMFT=0); thereby the regres- describe the pattern of oral health education level and they were care- sion coefficient indicates the Odds behaviour, illness behaviour, oral fully instructed in the rationality and Ratio (OR=P/1-P) of caries. For health knowledge and attitudes meaning of questions. Prior to the the statistical evaluation of the among 12-year-old and 18-year- data collection the questions were regression coefficients, the t-test was old Chinese at the national level; to pre-tested among comparable used in the dummy regression analyse the oral health behaviour groups of children in order to whereas the Wald-test was chosen profile of the two age groups in assess reliability and validity. In each in the logistic regression. relation to province and urbanisa- province one dentist was in charge tion, and to assess the relative of the organisation of clinical Results effect of socio-behavioural risk examinations as well as administra- factors on caries experience. tion of questionnaires. Oral hygiene habits Processing of data was performed Tables 1–2 summarise the findings by use of EPI-INFO v5.0 (Chinese concerning habits Study population and version) whereby data were checked of 12- and 18-year-olds. No signifi- methods for logical errors. The data entry cant differences in tooth brushing The present study is part of the took place in every province and behaviour were found according 2nd comprehensive national oral the staff members were carefully to gender. In all, nearly half of the health survey, which was completed trained on how to use the data respondents claimed to brush their in China in 199617. The study popu- input program. Double data entry teeth at least twice a day and such lation and principles of sampling was carried out. All questionnaires practice was reported more often have been detailed in previous were collected from each prov- in urban than in rural areas. The reports17,24. The participants of this ince, checked for logical errors by majority of children and adoles- survey were chosen by multistage use of EPI-INFO and the files were cents brushed their teeth in the

International Dental Journal (2003) Vol. 53/No.5 291

Table 1 The percentages of 12- and 18- year-old Chinese according to frequency of tooth brushing, occasion of brushing, use of toothpaste and age of starting brushing in relation to urbanisation

12 years 18 years Urban Rural Total Urban Rural Total (n=2200) (n=2200) (n=4400) (n=2200) (n=2200) (n=4400)

Frequency of tooth brushing seldom or no brushing 7.2 26.3 16.8 2.0 9.5 5.8 brushing once a day 33.7 42.8 38.2 45.8 54.9 50.3 brushing at least twice a day 59.1*** 31.0 45.0 52.1*** 35.6 43.9 Occasion of tooth brushing in the morning 94.9 88.6 91.8 94.0 88.8 91.4 in the evening 64.6*** 43.6 54.2 60.4*** 51.6 56.1 after meals 13.6 1.4 16.0 14.2 20.4 17.3 after dessert/sweets 21.0 14.5 17.8 17.0 21.0 18.9 Use of toothpaste non-fluoridated 77.3 89.1 83.2 87.5 92.6 90.0 fluoridated 22.7*** 10.9 16.8 12.5*** 7.4 10.0 Started brushing teeth before schooling 70.6 29.0 50.0 54.3*** 18.7 36.7 when attending primary school 28.9 69.8*** 49.1 41.0 69.6*** 55.2 after completing primary school 0.5 1.2 0.9 4.7 11.6 8.1

*** p<0.001

Table 2 The distribution (pct) of 12- and 18-year-old Chinese according to methods of toothbrushing, time spent on brushing, and preference of type of in relation to urbanisation

12 years 18 years Urban Rural Total Urban Rural Total

Method of brushing horizontal 18.5 40.2*** 29.3 18.2 28.6*** 23.3 LTD-recommended methods 65.9*** 44.0 55.1 52.2*** 45.7 49.0 no systematic methods 15.6 15.7 15.7 29.6 25.7 27.7 Time spent on brushing teeth less than 3 min. 71.6 66.4 69.1 82.6 78.6 80.6 3 min or more 28.4 33.6*** 30.9 17.4 21.4*** 19.4 Preference of type of toothbrush big head, hard bristle 2.6 5.8 4.2 5.2 9.0 7.1 big head, soft bristle 9.2 11.1 10.2 19.3 20.6 20.0 small head, hard bristle 13.6 19.5 16.5 17.4 18.8 18.1 small head, soft bristle 62.3*** 43.4 52.9 45.9*** 38.0 41.9 pig bristle 2.4 3.6 3.0 1.0 1.4 1.2 colour 2.6 4.8 3.7 4.0 3.2 3.6 don’t know 7.3 11.8 9.5 7.2 9.0 8.1

*** p<0.001 morning and about half the partici- participants started tooth brushing 18-year-olds claimed that they spent pants also brushed their teeth in the more often before attending 3 minutes or more on brushing evening, relatively more often by primary school than did the rural their teeth. with small urban respondents. For respond- participants. heads and soft bristles were mostly ents who claimed to brush their The ‘Love Teeth Day’ recom- preferred by the respondents, teeth once a day, about 90 per cent mendations of tooth brushing particularly in urban areas. In addi- reported brushing in the morning. include the vertical technique, roll- tion to tooth brushing, several other In general, fluoridated toothpaste ing or Bass-methods. As shown in means of cleaning were performed was used infrequently but some- Table 2, the recommended methods by the participants such as rinsing what higher proportions were used were performed most frequently of mouth with water after meals in urban areas. Half of the 12-year- by urban participants while hori- (73.3 per cent), use of salt water olds and one-third of 18-year-olds zontal brushing technique was more (15.5 per cent) or rinsing of mouth brushed their teeth before starting common in rural areas. One-third with tea (22.6 per cent). These prac- at school. At both ages, urban of 12-year-olds and one fifth of tices showed only minor variation

Zhu et al.: Oral 292

Table 3 The distribution (pct) of 12- and 18- year-old Chinese according to awareness of where tends to stick and the intervals for exchange of toothbrush in relation to urbanisation

12 years 18 years Urban Rural Total Urban Rural Total

Where does dental plaque stick to in the mouth on the 1.5 1.5 1.5 0.5 0.5 0.5 on the 9.6 9.0 9.3 12.8 12.5 12.7 on the teeth 13.8 10.2 12.0 11.1 8.9 10.0 all the above mentioned 6.8 7.5 7.1 14.3 17.9 16.1 never heard about plaque 30.2 34.7 32.5 25.0 26.4 25.7 don’t know 38.1 37.0 37.6 36.4 33.8 35.1 Intervals for exchange of toothbrush 1–3 months 53.2*** 38.9 46.1 46.3*** 43.3 44.8 4–6 months 20.4 18.7 19.6 29.3 27.7 28.5 7–12 months 6.4 7.7 7.0 8.1 11.2 9.7 more than one year 2.7 4.1 3.4 2.3 3.6 2.9 don’t know 17.4 30.6 23.9 14.0 14.2 14.1

*** p<0.001

Table 4 The percentages of 12- and 18-year-old Chinese according to the reason of brushing or not brushing their teeth in relation to urbanisation

12 years 18 years Urban Rural Total Urban Rural Total

Reasons of brushing teeth clean, bright teeth 45.5 38.4 42.0 74.5 68.1 71.3 prevention of caries 81.8*** 71.2 76.5 85.1*** 80.3 82.7 prevention of bleeding gums 50.0 46.6 48.3 63.9 62.7 63.3 prevention of oral ulcer 55.0 50.5 52.8 63.4 64.1 63.7 to get rid of foul breath 74.0 76.9 75.5 87.1 87.4 87.8 to set good example to others 5.9 6.5 6.2 7.7 7.9 7.8 Reasons of not brushing teeth bother me too much 8.1 10.0 9.0 10.9 10.4 10.6 no time for brushing 19.4 31.0*** 25.2 38.2 49.7*** 43.9 useless, good teeth are hereditary 1.4 3.8 2.6 1.8 2.2 2.0 gums are bleeding when brushing 6.3 12.7 9.5 7.0 8.7 7.9 no money for brush and toothpaste 0.5 2.5 1.5 0.8 2.9 1.8 nobody brush teeth in my family 0.5 2.7 1.6 0.3 2.0 1.2 don’t know of any benefits from brushing 2.1 6.0 4.1 1.2 2.2 1.7 always forget to brush my teeth 20.4 32.0*** 26.2 26.0 30.0*** 28.0 don’t like the smell of toothpaste 2.3 5.2 3.8 1.3 11.6 2.1

*** p<0.001 by age, gender or urbanisation. dental caries but this was particu- of Liaoning while the use of fluo- Table 3 shows at what level the larly found in urban areas (Table 4). ride toothpaste among 12-year-olds children were aware of the pres- Prevention of foul breath, oral was more common in Beijing, ence of dental plaque in the oral ulceration and bleeding gums were Guangdong and Shanghai. cavity. Significant proportions of also frequently given as reasons. the respondents had no knowledge Reasons for not brushing were or answered that they had never either that the participants had no Utilisation of dental services heard about plaque. The differences time or it was simply forgotten. Table 6 highlights the utilisation of by urbanisation in knowledge on Table 5 illustrates the differences dental services, with nearly half the dental plaque were less prominent. in tooth brushing habits by province. participants reporting that they had Nearly half of the participants held For both age groups, participants never seen a dentist. A dental visit the opinion that toothbrushes of the Guangdong province had within the previous 12 months was should be exchanged at intervals high scores on tooth brushing at not common but visits were some- of 1–3 months. least twice a day. Recommended what more often indicated by fe- The majority of respondents methods of brushing (vertical, roll- males (25.9 per cent) than males stated that tooth brushing was ing or Bass methods) were most (19.1 per cent) for the age group carried out in order to prevent frequently reported in the province 18 years. In all, about one-third of

International Dental Journal (2003) Vol. 53/No.5 293

Table 5 The percentages of 12- and 18-year-old Chinese with certain self-care practices in oral health according to province

Province Tooth brushing at least Recommended methods Use of twice a day of brushing toothpaste 12 years 18 years 12 years 18 years 12 years 18 years

Beijing 40 50 49 54 38 10 Shanghai 48 41 66 48 31 17 Tianjin 33 36 66 48 13 4 Gansu 32 19 55 53 8 3 Shandong 43 31 60 47 7 2 Yunnan 62 59 56 40 6 5 Liaoning 47 32 79 67 26 8 Zhejiang 40 48 58 46 19 12 Hubei 24 43 30 42 6 7 Guangdong 77 72 40 34 35 28 Sichuan 50 53 54 48 22 11 Total 45 44 46 42 19 11

Table 6 The distribution (pct) of 12- and 18-year-old Chinese according to how many times they had seen a dentist during lifetime (n=7897), time since last dental visit (n=5862) and preventive services received within the recent two years (n=5861) in relation to urbanisation

12 years 18 years Urban Rural Total Urban Rural Total

Number of times having seen a dentist never 30.0 53.2*** 41.7 41.4 62.7*** 52.2 1–2 times 38.4 30.1 34.2 30.2 22.5 26.3 3 or more times 31.5 16.8 24.1 28.4 14.9 21.6 Time since last visit to the dentist less than 1 year 28.6 34.8 31.3 22.0 23.3 22.5 1–2 years ago 30.7 24.7 28.1 17.0 16.6 16.8 3 or more years ago 31.7 19.0 26.1 46.6 31.5 40.0 never seen a dentist 9.0 21.6*** 14.5 14.5 28.6*** 20.6 Preventive services received during the recent two years check-up of teeth 37.1* 32.9 35.3 18.7 22.2* 20.2 topical application of fluoride 5.4*** 8.3 12.3 11.2*** 6.9 9.3 fissure sealing 9.7*** 5.3 7.8 8.3*** 4.7 6.7 scaling of teeth 20.8 23.9* 22.2 11.9 16.0** 13.7

*** p<0.001 ** p<0.01 * p<0.05 the participants had seen a dentist seen a dentist more than 10 times per cent for 18-year-olds) within the previous two years. reported tooth brushing at least (p<0.001). Among respondents who claimed twice a day against 34.1 per cent of Table 7 indicates the variation in having had a dental visit within two children who had never seen a utilisation of professional dental years, 36.3 per cent of 12 year-olds dentist (p<0.001). In addition, those services by province. The highest and 20.8 per cent of 18 year-olds with more than 10 dental visits proportion of 12-year-olds having reported that this was for a check- more often claimed to clean their seen a dentist within last year was up. Visits to the dentist for topical teeth according to methods recom- found in the Tianjin province, while application of fluorides and fissure mended by the dental profession at age 18 the highest percentage of sealing were rare, but more frequent (66.0 per cent v. 48.1 per cent for attendants was observed in the in urban than rural areas, in 12-year-olds and 59.7 per cent vs. Hubei province. For both ages contrast to scaling. 44.9 per cent for 18-year-olds) dental check-ups during the recent Self-care practices in terms of (p<0.001) and the use of fluoride two years were most frequent in frequency and method of brushing toothpaste was also somewhat Liaoning province. and use of fluoride toothpaste were more frequent among dental highly associated with dental visit- attendees than non-attendees (20.4 ing habits. Among 12-year-olds, per cent vs. 11.3 per cent for 12- Illness behaviour 66.9 per cent of children who had year-olds and 12.4 per cent vs. 7.5 As shown in Table 8, the main reac-

Zhu et al.: Oral health in China 294

Table 7 The percentages of 12- and 18-year-old Chinese with use of professional dental services according to province

Province Saw a dentist within Dental check-up during the last year the recent two years 12 years 18 years 12 years 18 years

Beijing 36.6 24.9 31.4 15.7 Shanghai 34.0 21.8 39.0 19.5 Tianjin 39.2 24.0 33.7 33.7 Gansu 22.8 12.5 28.8 13.3 Shandong 32.1 24.0 28.6 9.9 Yunnan 29.4 18.7 9.8 12.1 Liaoning 32.0 22.5 72.0 56.3 Zhejiang 32.2 29.3 30.8 17.5 Hubei 28.4 30.1 22.4 12.6 Guangdong 28.3 24.5 24.7 5.5 Sichuan 33.5 24.1 44.2 15.9 Total 31.3 22.5 35.3 20.2

Table 8 The percentages of 12- and 18-year-old Chinese who reported certain actions when having bleeding from gums or signs of caries in relation to urbanisation

12 years 18 years Urban Rural Total Urban Rural Total

If gums are bleeding what do you do stop brushing 10.0 12.5 11.2 16.9 16.9 16.9 pay more attention to gums when brushing 30.6 32.1 31.3 39.6 40.4 40.0 brush more frequently 35.0 39.0*** 37.0 45.2 52.3*** 48.8 go to see a dentist 36.7*** 29.1 32.9 23.5 23.4 23.5 ignore bleeding 9.3 16.1*** 12.7 25.4 26.8 26.1 never had this problem 32.2 28.0 30.0 19.7 21.8 20.8 don’t know what to do 12.7 21.6*** 17.1 24.3 26.6 25.5 If having signs of what do you do don’t care if no pain 12.8 22.0*** 17.4 40.8 42.0 41.4 take pills for pain killing 16.7 27.6*** 22.1 24.8 29.0** 26.9 just try to cope with the problem 11.2 19.8*** 15.5 26.0 29.5** 27.7 go and see a dentist only when in pain 28.0 31.3* 29.6 42.4* 38.7 40.5 go and see a dentist immediately for dental filling 49.2*** 27.2 38.2 31.5* 28.0 29.8 go and see a dentist for extraction of tooth 18.8 19.2 19.0 9.5 10.5 10.0 brush teeth more often when having pain 12.8 17.5*** 15.1 18.0 19.9 19.0

*** p<0.001 ** p<0.01 * p<0.05

sweets on a daily basis against 64.0 tions to bleeding gums were to Consumption of sweets per cent of males (p<0.001). brush the teeth more frequently and Furthermore, only weak correla- to see a dentist. At age 12, rela- Table 9 presents the proportions of tions were found between number tively more urban children would 12- and 18-year-olds who reported of dental visits and consumption seek help from the dentist in such having sweets between meals and of sugary drinks or frequency of situation while more rural children the frequency of eating sweets. sugary foods. would ignore bleeding. When About half of the participants had noticing signs of caries, about 40 sweets every day and the differ- per cent of 12 year-olds and 30 ence in this practice between urban Oral health information per cent of 18 year-olds answered and rural respondents was minor. In all, 41.7 per cent of the respond- that they would see a dentist, The consumption of sugary drinks ents had been informed about oral particularly among urban partici- was more frequent for urban health care, 47.2 per cent declared pants. On the other hand, several participants while slightly more that they never received any oral rural participants reported that they rural participants had sweets before health instruction while 11.3 per would try to cope with problems sleeping. In addition, at age 18, 81.5 cent were not aware of it. In 12- or control pain. per cent of females consumed year-olds, significantly more urban

International Dental Journal (2003) Vol. 53/No.5 295

Table 9 The percentages of 12- and 18- year-old Chinese with certain habits of consuming sweets and frequency of eating sweets in relation to urbanisation

12 years 18 years Urban Rural Total Urban Rural Total

Have sweets in-between-meals every day desserts or candy 46.3 48.9* 47.6 54.1* 52.0 53.0 sugary drinks 45.1*** 34.5 39.8 46.0*** 35.9 40.9 sweets before sleeping 13.3 18.5*** 15.9 19.9 26.0*** 23.0 Frequency of eating sweets 1–3 times per day 69.4 63.9 66.8 68.3 64.9 66.6 4–6 times per day 6.8 9.1 7.9 6.5 4.1 5.3 7–10 times per day 1.4 1.4 1.4 0.9 0.5 0.7 do not have such habits 22.4 25.6** 24.0 24.3 30.5*** 27.4

*** p<0.001 ** p<0.01 * p<0.05

Table 10 Multivariate dummy regression analysis of dental caries experience (DMFT) and logistic regression of Odds Ratio of dental caries (OR) among Chinese aged 12 (n = 4400) and 18 years (n = 4400) by urbanisation and oral health behaviour

12 yrs 18 yrs b OR b OR

Urbanisation Urban 0.01 0.04 0.15 1.02 Rural – – – – Number of times having seen a dentist 3 times or more 0.39*** 1.44*** 1.61*** 1.94*** 1–2 times 0.27*** 1.74*** 0.64*** 3.83*** Never seen a dentist – – – – Frequency of toothbrushing Brushing at least twice a day 0.09 0.94 0.03 0.99 Brushing once a day 0.03 0.93 –0.11 0.97 Seldom or no brushing – – – – Use of toothpaste Fluoridated –0.19** 0.86 –0.33** –0.82 Non–fluoridated – – – – Frequency of eating sweets 4 times or more/day 0.14 1.22** 0.23 1.05 3 times/day 0.21* 1.44* 0.27* 1.32* 2 times/day 0.13 1.24* 0.21* 1.48** 1 time/day 0.13 1.26 0.20* 0.16 No sweets – – – –

*** p < 0.001 ** p < 0.01 * p < 0.05

(60.0 per cent) than rural (36.8 per province (20.5 per cent). tion of molar caries” (74.6 per cent) children had received oral The majority of respondents cent), and “The effect of fluorides health information (p<0.001). At age gave the following answers to the in caries prevention is not clear” 18, both in urban and rural areas, statements about dental care: “It is (69.0 per cent). two thirds of the respondents necessary to brush or to floss teeth claimed never having received any every day” (82.6 per cent), “It is oral health instruction or that they not normal to have gums bleeding Multivariate analysis of dental were not aware of it. The propor- when brushing teeth” (60.9 per caries tion of participants who indicated cent), and “Regular dental check- Table 10 shows the results of the never having received oral health ups are necessary” (73.6 per cent). multivariate regression analyses of information was high for Hubei However, most participants answered dental caries experience and Odds province (61.0 per cent) while the “don’t know” to the statements Ratio (OR) of dental caries. figure was low for Guangdong “Sealants are effective to preven- Urbanisation and oral health habits

Zhu et al.: Oral health in China 296 were inserted as independent vari- ince and retest within one month while the proportion of children ables and the regression analyses after the questionnaire was completed brushing twice or more per day in were carried out for the two age initially; the consistency rate of the the Chinese study is somewhat groups separately. The most two sets of responses was more lower than found in similar studies important factors of the caries than 70 per cent23. However, the in Asia, such as in Thailand12. experience index were frequency data collection method may have Traditionally, Chinese people of dental visits, use of fluoridated certain limitations26. First, the have tended to practice an unsyste- toothpaste and frequency of eating participants may tend to give matic or horizontal method of sweets. The logistic regression socially desirable responses by over- brushing. In order to encourage model indicated higher odds of estimating the frequency of dental the Chinese population to adopt dental caries (OR) if the respond- visits or tooth brushing. Second, proper oral hygiene habits, the ents had frequent dental visits and participants may underestimate vertical, rolling or Bass-methods frequent consumption of sweets. negative behaviour such as consump- were considered most appropriate tion of sugar. Third, some over- by the LTD programme. The reporting would be considered present survey indicated that only Discussion likely with respect to the answers half of the respondents performed In China, socio-epidemiological on knowledge and attitudes towards the recommended methods of data on oral health status are scarce; dental care. brushing. The results may suggest in particular, systematic data on oral In China, several efforts have that growing numbers of Chinese health behaviour of children and been made to implement preven- children adopt regular tooth brush- adolescents are not available at tive oral care programmes and oral ing in early childhood since about national level. The present study health education since the late half of the 12-year-olds reported intended to provide such informa- 1980s. In 1988, the National Com- tooth brushing before they started tion with regard to 12- and 18- mittee for Oral Health (NCOH) at school. In comparison, for 18- year-olds of urban and rural areas. was established in order to prevent year-olds who were born before The emphasis was placed on dental and improve oral the LTD was introduced, the describing the level of oral health health behaviour of the public. The figure was only about one-third. knowledge, attitudes and behav- Love Teeth Day campaign (LTD) Furthermore, it is worth noting that iour of children and adolescents in has been organised as a mass oral the use of fluoridated toothpaste different regions of China and high- health education programme by was relatively seldom. If brushing lighting the impact of the national the NCOH and annually various was performed only once a day, it mass oral health education pro- activities were carried out through- apparently tended to take place in grammes, such as the national ‘Love out the country in order to encour- the morning rather than in the Teeth Day’ campaign17,25. The age the implementation of commu- evening, despite the LTD messages multistage random cluster sampling nity-based oral health education at emphasising tooth brushing to be procedure was applied for selec- province level25. The LTD campaigns carried out in the evening. This may tion of participants. Relatively more intended to pass on the following indicate that such habits are diffi- urban respondents took part in the messages for preventive practices cult to change merely through mass survey, although the epidemiologi- by the public: regular tooth brush- health education33. cal part of the study may be ing at least twice a day, performance The children and adolescents considered representative of the of standard methods of brushing, living in urban areas had regular general population17. tooth brushing from early child- oral hygiene habits more often than The sociological data were hood as well as the use of standard in rural areas. This may be due to collected by means of self-admin- toothbrushes and fluoridated factors such as better coverage of istered questionnaires and due to toothpaste. The present study the LTD programme in urban the school-based approach a high revealed that about half of children areas, higher socio-economic status response rate was obtained. Several and adolescents performed the and adoption of modern lifestyle. initiatives were made to ensure the recommended practice of brush- In addition, the use of a standard validity and reliability of data. The ing teeth twice a day or more. This toothbrush was significantly less questionnaires used in this study level is similar to that observed in frequent in rural areas than in were evaluated for optimal construct some industrialised countries of east urban areas, and this pattern may and face validity of variables by an Europe27–29 but low as compared be explained by the restricted avail- expert panel of oral health research- with most western industrialised ability of such brushes from the ers of the Chinese National Com- countries27,28. Moreover, oral self- market. Moreover, the differences mittee for Oral Health (NCOH). care practices of Chinese youths in oral hygiene habits by location The test-retest method was carried seemed to be more frequent than were reflected in other dimensions out in a sub-sample of each prov- observed in the Middle East13,30,31, of oral health behaviour when

International Dental Journal (2003) Vol. 53/No.5 297 responses were analysed according tant factors of caries experience habits of youth and better control to the province; for example, the were frequency of dental visit, use of oral disease. Guangdong province had high of fluoridated toothpaste, and scores on tooth brushing at least frequency of eating sweets whereas twice a day. the frequency of tooth brushing had Acknowledgement About half of the respondents minor impact on dental caries This survey was conducted by an had never visited a dentist at all. experience. Such pattern was also expert group under the Ministry of and this confirms findings from found in the previous studies Health and the National Committee the Wuhan19 and Guangdong20 stud- carried in China19,20 and in Thai- for Oral Health; it was supported ies carried out in the mid-1990s. land12. One reason of the limited financially by the China Oral Health However, less than one third of impact of tooth brushing may be Foundation and technical assistance the respondents reported a dental that oral self-care practices of was provided by the WHO visit in the previous 12 months, a Chinese children and adolescents Collaborating Centre for Commu- figure much lower than in previous are more problem-oriented rather nity Oral Health Programmes and Chinese studies19,20 or as reported than performed for preventive Research (University of Copenha- for children of industrialised coun- reasons. The problem-oriented gen, Denmark). tries27–30, the Middle East13,29,31,32 and dental visiting habits also explain South-East Asia12. In agreement the higher caries index among with a previous Chinese study33 one dental visitors. References third of respondents reported In general, attitudes to prevention 1. 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