Materials and methods. A total of 17 amalgams and 17 compomer restorations were placed in 17 children based on a split-mouth design. Restorations were assessed at 12- and 24-month intervals for marginal integrity, the anatomic form and recurrent caries. Data were analyzed with SPSS 11. Chi-squared test was applied for the analysis. Statistical significance was set at P<0.05. 

Results. A total 34 restorations of 28 restorations (14 pairs) of the total restorations still survived after 24 months. Compomer restorations showed significantly better results in marginal integrity. Recurrent caries was significantly lower in compomer restorations compared to amalgam restorations. Cumulative success rate at 24-month interval was significantly higher in compomer restorations compared to amalgam restorations. There was no statistically significant difference in anatomic form between the two materials. 

Conclusion. Compomer appears to be a suitable alternative to amalgam for Class II restorations in the first primary molars.