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Oral health disparities among adolescents from urban and rural communities of central Chile.

PURPOSE
Rural populations may be at increased risk for prevalent oral diseases. The aim of this study was to compare oral health status of adolescents of rural and urban areas from central Chile.


METHODS
A representative sample of 552 and 486 adolescents aged 12 and 15 years, respectively, was examined using WHO methods. Adolescents were chosen from schools belonging to urban and rural districts of the region. Caries status was obtained by decayed, missing, filled teeth (DMFT) and significant caries (SiC) indexes. The gingival exam included the oral hygiene index (OHI) of Silness and Löe and the gingival index (GI) of Löe and Silness. Clinical attachment loss and community periodontal index (CPI) were restricted to 15-year-old adolescents. Statistical comparisons of medians and means were performed with the Mann-Whitney U-test. To determine the association between caries experience and oral hygiene and gingival indexes, Spearman's correlation was used at p<0.05.


RESULTS
Twelve-year-old children from rural areas had caries prevalence of 67.50%, which was significantly higher (p<0.05) than children from urban areas, who had 54.04%. Caries experience of 12-year-old rural children was significantly higher (DMFT 3.36; standard deviation (SD) 2.71) than that of urban children (DMFT 2.29; SD 2.17) (p=0.0001). Rural adolescents also showed increased caries severity (SiC 6.21; SD 2.44), whereas urban children showed had a SiC of 4.71 (SD 1.74) (p=0.0001). For periodontal indexes, the average GI for 12-year-olds was 1.51 (SD 0.33), which corresponds to moderate inflammation, but rural subjects (GI 1.55; SD 0.34) had higher values (p=0.002) than their urban counterparts (GI 1.45; SD 0.29). In 15-year-old adolescents, caries prevalence was significantly higher in rural (73.58%) than in urban (64.59%) individuals (p<0.05). Although not significant, caries experience for 15-year-olds in rural areas, like in the other age group, was slightly higher than for urban 15-year-olds (DMFT 5.03; SD 3.61 and DMFT 4.65; SD 3.58, respectively) (p=0.238). The SiC in the rural subjects (9.16; SD 2.26) of this age group was significantly higher than for urban adolescents (8.51; SD 3.00). No significant differences either in the OHI (p=0.418) or in the GI (p=0.624) were observed between rural and urban participants.


CONCLUSIONS
Adolescents of central Chile show clear disparities in oral health, with rural communities more affected. Gingival health seems to be less impacted by rurality than caries experience. Other social determinants of oral health may also explain these results, and further research appears necessary.