Objective:To observe the bacteriostatic efficacy of bromogeramine of different concentrations made with potassium alginate impression materials.Methods:Based on the methods described in"Disinfection Technical Guidelines

2002 ed‘the second chapter-xxxx’"(Ministry of Public Health of the People’s Republic of China)

the bacteriostatic efficacy was evaluated through measuring the size of inhibition zone formed by mixing bromogeramine with potassium alginate impression material.Results:Bromogeramine of any concentration had no effect on Pseudomonas aeruginosa.When the concentration of bromogeramine was above 0.4 mg/ml

the size of bacterio- static ring did not change.However

when the concentration increased to 0.05%

0.1%

0.2%

or 0.4%

the diameter of the inhibition zone was increasinly enlarged.Conclusions:Bromogeramine of certain concentration had some bacteriostatic effect on bacteria except pseudomonas aeruginosa.Besides

the bacteriostatic efficacy increased with the concentration increasing

but it did not change when the concentration of bromogeramine was above 0.4 mg/ml.