AIM: This was to investigate survival rate, median survival time and differences in the progression of different stages of proximal caries in 196 children, aged 6 to 8 years old, with different caries index at baseline examination. METHODS: Based on DMFS/dmfs values, children were categorized as low, moderate and high caries index groups. Subjects with DMFS/dmfs smaller or equal to half of a child's age were classified as low caries index group, children with DMFS/dmfs greater to half and smaller than or equal to the child's age as moderate, while those with DMFS/dmfs greater than the child's age as high. Proximal caries and its progression were diagnosed from bitewing radiographs taken at 1-year intervals over a period of 4 years. The mesial surface of the first permanent molars, mesial and distal surfaces of the first and second primary molars and distal surfaces of the primary canines were examined. Sound surfaces, caries lesions in the external and internal half of the enamel and external, middle, internal third of the dentine as well as filled, extracted and exfoliated teeth were recorded. STATISTICS: A life table analysis was performed to estimate survival rate and median survival time of each state of proximal caries and differences between the groups in the progression of the proximal lesions were tested with the Wilcoxon pairwise comparison statistic. RESULTS: There were statistically significant differences in the caries rate of the sound proximal surfaces of the primary teeth between the low and high caries index groups. Also, statistically significant differences between these two groups were found in the progression of the external half of the enamel caries in the first permanent molars and in the primary teeth. CONCLUSIONS: A high caries index increases the risk of developing caries in the sound proximal surfaces of posterior primary teeth and causes faster progression of the external half of the enamel lesions in the first permanent molars and posterior primary teeth.
AIM: This was to investigate survival rate, median survival time and differences in the progression of different stages of proximal caries in 196 children, aged 6 to 8 years old, with different caries index at baseline examination. METHODS: Based on DMFS/dmfs values, children were categorized as low, moderate and high caries index groups. Subjects with DMFS/dmfs smaller or equal to half of a child's age were classified as low caries index group, children with DMFS/dmfs greater to half and smaller than or equal to the child's age as moderate, while those with DMFS/dmfs greater than the child's age as high. Proximal caries and its progression were diagnosed from bitewing radiographs taken at 1-year intervals over a period of 4 years. The mesial surface of the first permanent molars, mesial and distal surfaces of the first and second primary molars and distal surfaces of the primary canines were examined. Sound surfaces, caries lesions in the external and internal half of the enamel and external, middle, internal third of the dentine as well as filled, extracted and exfoliated teeth were recorded. STATISTICS: A life table analysis was performed to estimate survival rate and median survival time of each state of proximal caries and differences between the groups in the progression of the proximal lesions were tested with the Wilcoxon pairwise comparison statistic. RESULTS: There were statistically significant differences in the caries rate of the sound proximal surfaces of the primary teeth between the low and high caries index groups. Also, statistically significant differences between these two groups were found in the progression of the external half of the enamel caries in the first permanent molars and in the primary teeth. CONCLUSIONS: A high caries index increases the risk of developing caries in the sound proximal surfaces of posterior primary teeth and causes faster progression of the external half of the enamel lesions in the first permanent molars and posterior primary teeth.