We added two synthetic pyrimidine compounds to periodontal dressing materials and examined the increase in the area ratio of the tubule-like structure in vitro, in order to evaluate the effects on angiogenesis. Also, we examined the change in cell viability by adding these compounds. Both tests have shown that the level at which the formation of the tubule-like structure is facilitated is about 0.1 mM for both additives, and that at this level there were almost no effects on cell viability. Although the applicability of test periodontal dressing materials cannot be determined based solely on the results of this in vitro study, the application of these compounds to dentistry appears promising.