We gave a report on the model for dental diseases at the 1987 System Dynamics Conference. The model consists of 4 sectors: demography, cavities, pyorrhea and baby teeth. The demographic sector covered population of 5 three-year age groups under 14 years of age and 13 five-year age groups above 15 years of age. The cavities sectors and pyorrhea sector were composed of population of five-years age groups, on the other hand, the baby teeth sector used population of three-year age groups.From the total number of defective teeth, total dental costs in Japan were calculated annually from 1963 and projected to 2025. We added to this model a new level variable which is technology (rate variables and multipliers) in order to demonstrate to the effect of technology on the other level variables. New simulation results will be reported at the International System Dynamics Conference this year.