RELATIONSHIPS BETWEEN FREE SMOOTH SURFACE AND PROXIMAL CARIES IN THE YOUNG PERMANENT DENTITION

Cross-sectional relationships between free smooth surface and proximal caries were assessed in 3 age groups, comprising 252 subjects aged 12 yr, 301 aged 15-16 yr and 102 aged 18-19 yr. Caries diagnosis was cli nically on white spot and radiographically on enamel lesion level. Fai r correlation between buccal-lingual and proximal caries observed amon g 12-yr-olds (r=0.47) declined in the older subjects (r=0.24). While s tatistically significant the variability in proximal caries, explained by buccal-lingual lesions, was low (range 6-22%). Sensitivity and spe cificity for buccal-lingual lesions as an indicator for proximal carie s in the same tooth ranged from 0.37-0.44 and 0.84-0.91, respectively, with associated Pv+ and Pv- ranging from 0.41-0.44 and 0.84-0.91, res pectively. Sensitivity and specificity for buccal-lingual caries in id entifying subjects with proximal caries ranged from 0.33-0.44 and 0.67 -0.98, respectively. Pv+ ranged from 0.94-0.99 and Pv- from 0.06-0.35. ROC curve analysis yielded A(z)-values of about 0.76 in the two young er age groups and 0.57 in the oldest. The results imply that informati on obtained from visual examination should be applied with caution whe n inferences about current caries status on proximal surfaces are made from the presence of buccal-lingual caries.