Short Communication Caries Res 2014;48:347–352 DOI: 10.1159/000357226
Received: March 20, 2013 Accepted: November 8, 2013 Published online: March 6, 2014
Tooth Loss Prevalence and Risk Indicators among 12-Year-Old Schoolchildren from South Brazil L.S. Alves a C. Susin b N. Damé-Teixeira a M. Maltz a a
Department of Social and Preventive Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; b Department of Periodontics and Oral Biology, Georgia Regents University, Augusta, Ga., USA
Abstract This population-based cross-sectional study aimed to assess the prevalence and risk indicators for tooth loss due to dental caries among 12-year-old schoolchildren from South Brazil. 1,528 out of 1,837 (participation rate = 83.17%) schoolchildren were included. Tooth loss prevalence was 5.81% (95% CI = 3.71–8.98) and 0.08 (95% CI = 0.04–0.12) teeth were missing. Schoolchildren with low socioeconomic status (OR = 2.28, 95% CI = 1.23–4.21), who repeated years in school (OR = 1.56, 95% CI = 1.01–2.42), and with gingivitis (OR = 1.81, 95% CI = 1.33–2.45) were more likely to have missing teeth. Schoolchildren brushing 2 times/day (OR = 0.78, 95% CI = 0.64–0.96) or more (OR = 0.49, 95% CI = 0.33– 0.74), and those with dental insurance or private dentists (OR = 0.60, 95% CI = 0.39–0.93) were less likely to present missing teeth. © 2014 S. Karger AG, Basel
© 2014 S. Karger AG, Basel 0008–6568/14/0484–0347$39.50/0 E-Mail [email protected] www.karger.com/cre
Tooth loss is a complex phenomenon associated not only with oral disease and trauma but also dental care availability and treatment philosophy. Tooth loss may lead to loss of function, impaired esthetics and ultimately to compromised quality of life [Gerritsen et al., 2010]. Early tooth loss has been associated with extensive tooth loss in adulthood [Eklund and Burt, 1994]. Whereas a wealth of data on the global epidemiology of dental caries among 12-year-old children has been generated in the last decades, limited information regarding tooth loss prevalence and risk factors is available. Studies have reported prevalence rates ranging from 8.9 to 40.9% among adolescents aged 12–19 years [Casanova-Rosado et al., 2005; Susin et al., 2006; Atieh, 2008; Barbato and Peres, 2009]. Socioeconomic indicators such as family income, parents’ educational level and socioeconomic status have been consistently associated with tooth loss [Thomson et al., 2000; López and Baelum, 2006; Susin et al., 2006; Barbato and Peres, 2009]. In contrast, evidence regarding the association between gender and tooth loss among adolescents is inconclusive [Thomson et al., 2000; CasanovaRosado et al., 2005; López and Baelum, 2006; Barbato and Peres, 2009]. The relationship between dental care and Marisa Maltz Faculty of Dentistry – UFRGS, Department of Social and Preventive Dentistry Ramiro Barcelos, 2492 Porto Alegre, RS 90035-003 (Brazil) E-Mail marisa.maltz @ gmail.com
Downloaded by: John Rylands Library 130.88.90.140 - 5/14/2015 6:01:12 PM
Key Words Epidemiology · Permanent dentition · Prevalence · Risk factors · Tooth loss
Subjects and Methods Target Population and Sampling This cross-sectional survey was conducted in Porto Alegre, southern Brazil, from September 2009 to December 2010 [Alves et al., 2013]. The target population included all consenting schoolchildren aged 12 years. A multistage probability sampling strategy was used and the primary sampling unit consisted of five geographical areas organized according to the municipal water fluoridation system. Water fluoridation was implemented in 1975 and Porto Alegre has a water supply system that reaches almost 100% of the households. Within each area, schools were randomly selected proportional to the number of existing public and private schools (42 schools: 33 public and 9 private). Schoolchildren born in 1997 or 1998 were then randomly selected proportional to school size. The sample size calculation for this oral survey used data about dental caries because it was readily available and it was likely to yield the highest sample size (worst-case scenario 50%) of disease estimates for this population. The following parameters were used: prevalence of 60% [Barbachan e Silva and Maltz, 2001], precision level of ±3%, 95% confidence intervals (CI), and a design effect of 1.3. Thus, a sample size of 1,331 was considered necessary, to which was added a nonresponse rate of 40%, resulting in a sample size of 1,837 individuals. Data Collection A questionnaire was sent to parents/legal guardians to gather information on socioeconomic status, parents’ educational level, number of rooms in the house, number of people living in the house, access to dental services, and dental brushing frequency. Information regarding the school year that the student was attending was also recorded. Clinical examinations were conducted at the schools, with the students in a supine position, using artificial light, air compressor and suction. A trained examiner (N.D.T.) recorded the gingival bleeding index [Ainamo and Bay, 1975]. A calibrated examiner (L.S.A.) assessed dental caries experience [World Health Organization, 1997]. Cohen’s kappa for caries examination was >0.8 (unweighted). In order to minimize error during the fieldwork, all interview and clinical data forms were reviewed by the participating dentists before moving to the next school. The computer data files were compared with the original data sheets to check for and correct any typographical errors. Thereafter, basic frequency tables were generated to identify out-of-range values and outliers. These were identified and corrected.
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Caries Res 2014;48:347–352 DOI: 10.1159/000357226
Nonresponse Analysis Of the 337 and 1,500 schoolchildren who were selected from private and public schools, 76 and 233 did not participate, yielding response rates of 77.44 and 84.46%, respectively. Telephone contact was established with 176 parents/legal guardians of the nonrespondents and the following reasons for nonparticipation were given: 26% reported no interest due to previous access to dental care, 27% of schoolchildren refused to participate, 24% did not return the informed consent or questionnaire, and 4% showed concern about biosafety or refused to answer socioeconomic questions. Nineteen percent of students were not available at school during the normal survey schedule. A random sample of nonrespondents was selected and information for 80 schoolchildren was obtained. After comparing participants and nonrespondents with regards to demographics, socioeconomic status and family-related data, small discrepancies were observed. Further information regarding the nonresponse analysis can be found elsewhere [Alves et al., 2013]. Data Analysis The primary outcome of this study was tooth loss prevalence, defined as the percentage of schoolchildren having at least one missing tooth or root tip. Socioeconomic status was categorized using cutoff points proposed by the Standard Brazilian Economic Classification [Brazilian Association of Research Companies, 2009] into low (≤13 points), mid-low (≥14 to ≤22 points), midhigh (≥23 to ≤28 points) and high (≥29 points) socioeconomic status. Due to the reduced number of individuals presenting missing teeth in the high socioeconomic status category, mid-high and high categories were combined. Household crowding was calculated as the number of persons per room, and it was categorized into low (≤0.6 persons/room), medium (>0.6 to ≤1 persons/room) and high crowding (>1 person/room), according to data distribution. School year was dichotomized into regular (5th, 6th or 7th grades) and late students (4th grade or earlier). Regarding the last dental visit, schoolchildren were categorized into those who visited a dentist in the last year, those who visited a dentist 2 years ago or more and those who had never visited a dentist. Type of dental service was classified as public health system, insurance/private and none. Gingivitis was categorized according to the percentage of sites with bleeding (8 years (n = 639) 2.72 (1.12 – 6.42) Crowdinga Low (n = 351) 2.74 (0.82 – 8.77) Medium (n = 826) 6.21 (4.09 – 9.32) High (n = 350) 8.52 (6.01 – 11.93) School Private (n = 261) 1.80 (0.26 – 11.53) Public (n = 1,267) 6.94 (4.81 – 9.92) School year Regular (n = 1,219) 4.78 (2.69 – 8.33) Late (n = 309) 10.28 (6.90 – 15.03) Last dental visit ≤1 year ago (n = 844) 5.60 (2.93 – 10.45) ≥2 years ago (n = 354) 6.93 (3.99 – 11.77) Never visited a dentist (n = 330) 5.16 (2.53 – 10.24) Type of dental services Public health system (n = 487) 9.58 (7.78 – 11.75) Insurance/private (n = 711) 3.80 (1.77 – 7.97) Never visited a dentist (n = 330) 5.16 (2.53 – 10.24) Brushing frequency ≤1 time/day (n = 341) 9.34 (6.86 – 12.61) 2 times/day (n = 677) 5.85 (3.79 – 8.94) ≥3 times/day (n = 510) 3.55 (1.63 – 7.55) Gingivitis (sites)b
Received: March 20, 2013 Accepted: November 8, 2013 Published online: March 6, 2014
Tooth Loss Prevalence and Risk Indicators among 12-Year-Old Schoolchildren from South Brazil L.S. Alves a C. Susin b N. Damé-Teixeira a M. Maltz a a
Department of Social and Preventive Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; b Department of Periodontics and Oral Biology, Georgia Regents University, Augusta, Ga., USA
Abstract This population-based cross-sectional study aimed to assess the prevalence and risk indicators for tooth loss due to dental caries among 12-year-old schoolchildren from South Brazil. 1,528 out of 1,837 (participation rate = 83.17%) schoolchildren were included. Tooth loss prevalence was 5.81% (95% CI = 3.71–8.98) and 0.08 (95% CI = 0.04–0.12) teeth were missing. Schoolchildren with low socioeconomic status (OR = 2.28, 95% CI = 1.23–4.21), who repeated years in school (OR = 1.56, 95% CI = 1.01–2.42), and with gingivitis (OR = 1.81, 95% CI = 1.33–2.45) were more likely to have missing teeth. Schoolchildren brushing 2 times/day (OR = 0.78, 95% CI = 0.64–0.96) or more (OR = 0.49, 95% CI = 0.33– 0.74), and those with dental insurance or private dentists (OR = 0.60, 95% CI = 0.39–0.93) were less likely to present missing teeth. © 2014 S. Karger AG, Basel
© 2014 S. Karger AG, Basel 0008–6568/14/0484–0347$39.50/0 E-Mail [email protected] www.karger.com/cre
Tooth loss is a complex phenomenon associated not only with oral disease and trauma but also dental care availability and treatment philosophy. Tooth loss may lead to loss of function, impaired esthetics and ultimately to compromised quality of life [Gerritsen et al., 2010]. Early tooth loss has been associated with extensive tooth loss in adulthood [Eklund and Burt, 1994]. Whereas a wealth of data on the global epidemiology of dental caries among 12-year-old children has been generated in the last decades, limited information regarding tooth loss prevalence and risk factors is available. Studies have reported prevalence rates ranging from 8.9 to 40.9% among adolescents aged 12–19 years [Casanova-Rosado et al., 2005; Susin et al., 2006; Atieh, 2008; Barbato and Peres, 2009]. Socioeconomic indicators such as family income, parents’ educational level and socioeconomic status have been consistently associated with tooth loss [Thomson et al., 2000; López and Baelum, 2006; Susin et al., 2006; Barbato and Peres, 2009]. In contrast, evidence regarding the association between gender and tooth loss among adolescents is inconclusive [Thomson et al., 2000; CasanovaRosado et al., 2005; López and Baelum, 2006; Barbato and Peres, 2009]. The relationship between dental care and Marisa Maltz Faculty of Dentistry – UFRGS, Department of Social and Preventive Dentistry Ramiro Barcelos, 2492 Porto Alegre, RS 90035-003 (Brazil) E-Mail marisa.maltz @ gmail.com
Downloaded by: John Rylands Library 130.88.90.140 - 5/14/2015 6:01:12 PM
Key Words Epidemiology · Permanent dentition · Prevalence · Risk factors · Tooth loss
Subjects and Methods Target Population and Sampling This cross-sectional survey was conducted in Porto Alegre, southern Brazil, from September 2009 to December 2010 [Alves et al., 2013]. The target population included all consenting schoolchildren aged 12 years. A multistage probability sampling strategy was used and the primary sampling unit consisted of five geographical areas organized according to the municipal water fluoridation system. Water fluoridation was implemented in 1975 and Porto Alegre has a water supply system that reaches almost 100% of the households. Within each area, schools were randomly selected proportional to the number of existing public and private schools (42 schools: 33 public and 9 private). Schoolchildren born in 1997 or 1998 were then randomly selected proportional to school size. The sample size calculation for this oral survey used data about dental caries because it was readily available and it was likely to yield the highest sample size (worst-case scenario 50%) of disease estimates for this population. The following parameters were used: prevalence of 60% [Barbachan e Silva and Maltz, 2001], precision level of ±3%, 95% confidence intervals (CI), and a design effect of 1.3. Thus, a sample size of 1,331 was considered necessary, to which was added a nonresponse rate of 40%, resulting in a sample size of 1,837 individuals. Data Collection A questionnaire was sent to parents/legal guardians to gather information on socioeconomic status, parents’ educational level, number of rooms in the house, number of people living in the house, access to dental services, and dental brushing frequency. Information regarding the school year that the student was attending was also recorded. Clinical examinations were conducted at the schools, with the students in a supine position, using artificial light, air compressor and suction. A trained examiner (N.D.T.) recorded the gingival bleeding index [Ainamo and Bay, 1975]. A calibrated examiner (L.S.A.) assessed dental caries experience [World Health Organization, 1997]. Cohen’s kappa for caries examination was >0.8 (unweighted). In order to minimize error during the fieldwork, all interview and clinical data forms were reviewed by the participating dentists before moving to the next school. The computer data files were compared with the original data sheets to check for and correct any typographical errors. Thereafter, basic frequency tables were generated to identify out-of-range values and outliers. These were identified and corrected.
348
Caries Res 2014;48:347–352 DOI: 10.1159/000357226
Nonresponse Analysis Of the 337 and 1,500 schoolchildren who were selected from private and public schools, 76 and 233 did not participate, yielding response rates of 77.44 and 84.46%, respectively. Telephone contact was established with 176 parents/legal guardians of the nonrespondents and the following reasons for nonparticipation were given: 26% reported no interest due to previous access to dental care, 27% of schoolchildren refused to participate, 24% did not return the informed consent or questionnaire, and 4% showed concern about biosafety or refused to answer socioeconomic questions. Nineteen percent of students were not available at school during the normal survey schedule. A random sample of nonrespondents was selected and information for 80 schoolchildren was obtained. After comparing participants and nonrespondents with regards to demographics, socioeconomic status and family-related data, small discrepancies were observed. Further information regarding the nonresponse analysis can be found elsewhere [Alves et al., 2013]. Data Analysis The primary outcome of this study was tooth loss prevalence, defined as the percentage of schoolchildren having at least one missing tooth or root tip. Socioeconomic status was categorized using cutoff points proposed by the Standard Brazilian Economic Classification [Brazilian Association of Research Companies, 2009] into low (≤13 points), mid-low (≥14 to ≤22 points), midhigh (≥23 to ≤28 points) and high (≥29 points) socioeconomic status. Due to the reduced number of individuals presenting missing teeth in the high socioeconomic status category, mid-high and high categories were combined. Household crowding was calculated as the number of persons per room, and it was categorized into low (≤0.6 persons/room), medium (>0.6 to ≤1 persons/room) and high crowding (>1 person/room), according to data distribution. School year was dichotomized into regular (5th, 6th or 7th grades) and late students (4th grade or earlier). Regarding the last dental visit, schoolchildren were categorized into those who visited a dentist in the last year, those who visited a dentist 2 years ago or more and those who had never visited a dentist. Type of dental service was classified as public health system, insurance/private and none. Gingivitis was categorized according to the percentage of sites with bleeding (8 years (n = 639) 2.72 (1.12 – 6.42) Crowdinga Low (n = 351) 2.74 (0.82 – 8.77) Medium (n = 826) 6.21 (4.09 – 9.32) High (n = 350) 8.52 (6.01 – 11.93) School Private (n = 261) 1.80 (0.26 – 11.53) Public (n = 1,267) 6.94 (4.81 – 9.92) School year Regular (n = 1,219) 4.78 (2.69 – 8.33) Late (n = 309) 10.28 (6.90 – 15.03) Last dental visit ≤1 year ago (n = 844) 5.60 (2.93 – 10.45) ≥2 years ago (n = 354) 6.93 (3.99 – 11.77) Never visited a dentist (n = 330) 5.16 (2.53 – 10.24) Type of dental services Public health system (n = 487) 9.58 (7.78 – 11.75) Insurance/private (n = 711) 3.80 (1.77 – 7.97) Never visited a dentist (n = 330) 5.16 (2.53 – 10.24) Brushing frequency ≤1 time/day (n = 341) 9.34 (6.86 – 12.61) 2 times/day (n = 677) 5.85 (3.79 – 8.94) ≥3 times/day (n = 510) 3.55 (1.63 – 7.55) Gingivitis (sites)b
