Blood contamination of environmental surfaces in outpatient oral surgery operatory

High-speed instruments potentially produce large amounts of contaminated splatters and aerosols during dental procedures. To evaluate the dissemination of blood and distribution of frequent contaminations, we investigated blood contamination on environmental surfaces of equipment in an outpatient procedure room. Test samples were collected with disposable alcohol cotton from 443 portions on the surfaces of medical equipment, and a leucomalachite green blood detection test was then applied. Positive results were common for dental chair equipment requiring frequent hand contact, such as the controller of the electric coagulator (46.2%, 6/13) and armrest (36.4%, 4/11). On the surfaces with minimal hand contact, positive results were observed on the surface of the light arm (35.7%, 5/14) and bracket table arm (12.5%, 2/16). Housekeeping surfaces with frequent hand contact such as the sliding door knob (22.2%, 4/18) and towel case (33.3%, 1/3) also showed positive results. Another 36 samples were collected from surfaces of the PC system. Positive reactions were observed on the keyboard (14.3%, 1/7) and display (33.3%, 2/6), although no blood was detected on the mouse controller, PC body or desk. Possible routes of blood contamination seemed to be blood-contaminated splatters and medical staff-associated hand contact. As blood stains were all invisible on the surfaces of frequent hand-contact equipment, these results appear useful for cleaning and disinfection protocols.