PURPOSE: The aim of the study was to evaluate the clinical performance of a high powder:liquid ratio self-cure glass ionomer cement in the restoration of primary molars. METHODS: Fuji IX GP (GC International, Tokyo, Japan) was used to restore 129 carious cavities (56 1-surface; 73 2-surface) in 69 patients of mean age 6 y 7 mo. Approximal cavities were prepared with a slot only design, and all cavities were small to medium in size. Restorations were evaluated at 6 mo, 1 y and 2 y using USPHS criteria, and the survival rate calculated using survival analysis. RESULTS: The cumulative survival rate of single-surface restorations was 100 percent at 2 y, and of 2-surface restorations was 99 percent at 6 months and 1 year, and 93 percent at 2 y. All failures were due to loss of restoration. The overall USPHS alfa ratings at 2 y were: marginal discoloration, 96 percent; anatomic form, 100 percent; marginal adaptation, 99 percent. There was no incidence of secondary caries. CONCLUSIONS: A high powder:liquid ratio glass ionomer cement was successful over 2 years in the restoration of small-medium sized cavities in primary teeth. It is predictable that the performance will continue to be highly satisfactory over the next 2-3 years.