The purpose of this study was to estimate and compare the Significant Caries Index (SiC), the pattern of sugar consumption, and to know the oral hygiene practices in a sample of 200, 12-year-old school going children of two different social classes residing in both urban and rural areas. The subjects were divided into two social classes based on the per capita monthly income. Twenty-four hour dietary records of five consecutive days were obtained from each subject. The results showed that all the subjects brushed daily. More number of children belonging to social class I and urban area brushed twice a day. While there were no significant differences in DMFT among the study groups, SiC index was higher in males, subjects of social class I, and urban residents. Sweet score, Total sugar exposure and Between-meal sugar exposure were more in males, subjects of social class I, and urban residents, whereas At-meal sugar exposure was more in females, subjects of social class II, and rural residents. From a preventive point of view, males, subjects of higher socioeconomic background, and urban residents seem to be the most important target groups for dental health communication programs focusing on the frequency of sugar consumption and dietary counselling.