Objective The objective was to test whether the ranking of countries was different using the SFS-T (Significant Filled Sound-Teeth Index) or the Significant Caries Index (SiC). Method This study compared the country rankings using the SiC and the SFS-T indices in 12 year olds in a range of countries. The SFS-T is the one-third of the population with the lowest filled or sound teeth and is a measure of functional status. We used the SiC and DMFT data from the WHO database for 12 year olds. SFS-T index values were estimated for the 12 year olds for 16 countries. Results The ranking by SiC index scores was lower for developed countries than for developing countries. Conclusions These findings suggest that it may be more useful to use the SFS-T index than the SiC index in studies comparing dental status between countries.