[Study of caries polarization in 2-5 year-old children of Shenyang, China].

Objective: To investigate dental caries polarization in 2-5 year-old children.

Methods: 3 799 random samples of 2-5 year-old children from attending kindergarten in Shenyang were selected. Means of dmft index and SiC index for each age group were calculated by WHO Collaborating Center. The subjects of each age group were further divided into subgroups of different level of dmft: the dmft of subgroup I was 0, the dmft of subgroup II was 1, the dmft of subgroup III was 2, the dmft of sub-group IV was equal to or more than 3. The obtained data were analyzed statistically with SPSS 10.0.

Results: 4.5% of 2-year-old children were carriers of 60.0% of the total dmft in that age group, 13.2% of 3-year-old children were carriers of 69.4% of the total dmft in that age group, 34.4% of 4-year-old children were carriers of 86.6% of the total dmft in that age group, and 47.8% of 5-year-old children were carriers of 89.8% of the total dmft of that age group.

Conclusion: This study supports the assertion that a small percentage of persons with high dental caries rate and a large percentage of caries-free persons of early childhood caries.