Qin Du1,2, Ming Yu2, Yueling Li2, Haojing Du2, Wenlan Gao3, Hao Mei1,4, Shijian Liu1. 1. School of Public Health and Department of Clinical Epidemiology, Pediatric Translational Medicine Institute, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, China. 2. Jiading District Dental Hospital, Shanghai, China. 3. Department of Dentistry, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai, China. 4. Center of Biostatistics and Bioinformatics, University of Mississippi Medical Center, Jackson, MS, USA.
Abstract
OBJECTIVES: The aim of this study was to evaluate the association between caries experience in primary teeth and caries experience in permanent teeth in a longitudinal study. METHODS: Teeth were examined at 5 years of age and a follow-up examination was conducted 7 years later at 12 years of age in all children from Jiading District, Shanghai, China. A total of 1885 participants were recruited in the study; 1683 students were followed up and 202 students (10.7%) were lost to follow up. Data were analyzed using the chi-square test, t-test and risk ratio. RESULTS: The followed-up samples comprised 883 boys (52.5%) and 800 girls (47.5%). At initial examination, the prevalence of dental caries was 67.4% in boys and 66.5% in girls (χ² = 0.2, P = 0.70), with mean decayed, missing and filled teeth (dmft) scores of 3.5 ± 0.1 and 3.4 ± 0.1, respectively (t = 0.1, P = 0.90). At follow-up, the prevalence of dental caries was 33.9% in boys and 37.9% in girls (χ² = 2.9, P = 0.11), with mean DMFT scores in permanent teeth of 0.7 ± 0.0 and 0.8 ± 0.1, respectively (t = 1.2, P = 0.24). The group of 5-year-olds with caries had a significantly higher prevalence of caries in permanent teeth (45.5%) at 12 years of age than the group of 5-year-olds without caries (16.0%) (χ2 = 141.1, P < 0.001, risk ratio = 1.5). Caries risk in permanent teeth was significantly higher with greater dmft scores (χ2 for trend = 31.1, P < 0.001). CONCLUSIONS: Caries in primary teeth is a major risk factor for caries in permanent teeth. The likelihood of caries in permanent teeth is higher with greater dmft scores in primary teeth.
OBJECTIVES: The aim of this study was to evaluate the association between caries experience in primary teeth and caries experience in permanent teeth in a longitudinal study. METHODS: Teeth were examined at 5 years of age and a follow-up examination was conducted 7 years later at 12 years of age in all children from Jiading District, Shanghai, China. A total of 1885 participants were recruited in the study; 1683 students were followed up and 202 students (10.7%) were lost to follow up. Data were analyzed using the chi-square test, t-test and risk ratio. RESULTS: The followed-up samples comprised 883 boys (52.5%) and 800 girls (47.5%). At initial examination, the prevalence of dental caries was 67.4% in boys and 66.5% in girls (χ² = 0.2, P = 0.70), with mean decayed, missing and filled teeth (dmft) scores of 3.5 ± 0.1 and 3.4 ± 0.1, respectively (t = 0.1, P = 0.90). At follow-up, the prevalence of dental caries was 33.9% in boys and 37.9% in girls (χ² = 2.9, P = 0.11), with mean DMFT scores in permanent teeth of 0.7 ± 0.0 and 0.8 ± 0.1, respectively (t = 1.2, P = 0.24). The group of 5-year-olds with caries had a significantly higher prevalence of caries in permanent teeth (45.5%) at 12 years of age than the group of 5-year-olds without caries (16.0%) (χ2 = 141.1, P < 0.001, risk ratio = 1.5). Caries risk in permanent teeth was significantly higher with greater dmft scores (χ2 for trend = 31.1, P < 0.001). CONCLUSIONS: Caries in primary teeth is a major risk factor for caries in permanent teeth. The likelihood of caries in permanent teeth is higher with greater dmft scores in primary teeth.