Disinfection efficiency of different disinfectants on dental impressions and the dimensional stability of impressions after disinfection / 中国组织工程研究

ABSTRACT

BACKGROUND:The surface of dental impression is inevitable to carry various bacteria caused by direct contact with the patient saliva, mucosa and blood during preparation;therefore, disinfection of the dental impression is necessary. OBJECTIVE:To evaluate the disinfection efficiency of glutaraldehyde, chlorine dioxide and electrolyzed oxiding water on dental impressions and to investigate the dimensional stability of impressions after disinfection, thus providing basis for establishing a standard and reasonable disinfection method. METHODS:Alginate impression materials were contaminated in vitro, and then immersed in glutaraldehyde, chlorine dioxide and electrolyzed-oxiding water for 5, 10 and 15 minutes, respectively. The colonies were counted after germiculture to compare the disinfection efficiency of three disinfectants. The impressions were poured in die stone after immersion, the dental models were structured-light scanned and three-dimensional digital dental models were reconstructed. Al the data were global y registered, and linear dimensions were measured on the digital models to deduce the influence of disinfection on surface accuracy and dimensional stability of the impressions. RESULTS AND CONCLUSION:The disinfecting rate reached 100%through immersion in 2%alkaline glutaraldehyde for 5 minutes, and the disinfection of kil ing the hepatitis B virus was effective after 10-minute immersion. The disinfecting rate of 600 ppm chlorine dioxide for 15 minutes kil ing experimental bacteria reached 99%and effective for kil ing the hepatitis B virus. While the disinfecting rate of kil ing experimental bacteria was less than 99%through immersion in electrolyzed oxiding water for 15 minutes, and was not effective for hepatitis B virus. The three-dimensional digital dental models did not differ significantly. These results suggest that immersion in 2%alkaline glutaraldehyde for 10 minutes or 600 ppm chlorine dioxide for 15 minutes can effectively disinfect alginate impressions and make no significant effect on the dimensional stability.