Comparative Evaluation of Caries Status in Primary and Permanent Molars in 7–8-year-old Schoolchildren of Shimla Using Caries Assessment Spectrum and Treatment Index

BACKGROUND A new epidemiological index is introduced for full assessment of dental caries which is known as caries assessment spectrum and treatment (CAST). "Spectrum" is considered backbone of this index as it covers from no lesion to advanced stage progression of caries. We aimed to evaluate and compare the status of caries in primary and permanent molars of 7-8-year-old schoolchildren of Shimla using CAST index and to find if any correlation exists between the status of caries in evaluated teeth. METHODS Three hundred and one schoolchildren with age group of 7-8 years were selected from schools in Shimla. CAST codes were determined for primary molars and first permanent molars. The distribution of CAST codes in the examined molars is correlated with the help of Spearman's rank correlation coefficient. The level of statistical significance was established at P < 0.05. The intraexaminer reliability was determined by the unweighted kappa coefficient. RESULTS Caries was assessed in 6.3%-12.3% of the permanent molars in contrast to primary molars, in which caries was near about 50%. The correlation was stronger for first and second deciduous molars for the right side of the mouth than the left side (r = 0.293 and 0.257 in the maxilla and 0.503 and 0.319 in the mandible [P < 0.001], respectively, while correlation for teeth in opposite jaws was moderate [r = 0.20-0.47]). The intraexaminer reliability was examined (k = 0.90 for the primary and 0.85 for permanent molars). CONCLUSION The correlation between primary and permanent molars regarding the caries status in primary molars is weak while strongest correlation was present on the right side of the mouth for first and second deciduous molars. The study also showed the applicability of the CAST index in epidemiological surveys.