Effectiveness of different desinfections/sterilization protocols for heat sensitive orthodontics instruments

Resumo

Objective: The aim of this work was to assess effectiveness of different disinfections/ high level disinfection protocols for heat-sensitive orthodontics instruments. Methods: Eight protocols were applied to orthodontic instruments (n=120); they were cleaned with dual- or triple-enzyme detergent and disinfected with glutaraldehyde 2.5% or hypochlorite 1% or orthophthalaldehyde 0.55%.After applying each protocol, samples were taken from the instruments and cultured in MacConkey Agar and CLED Agar media. For Staphylococcus spp, a coagulase test was used. Instruments were considered contaminated when the CFU count from the cultures was greater than 105 CFU/ml. Results: The same proportion of contamination was found when using glutaraldehyde and sodium hypochlorite, and no significant differences were found with the use of dual-enzyme and triple-enzyme detergents. Of the three disinfectants used, orthophthalaldehyde was significantly more efficient, since contamination was never found when it was used. The microorganisms isolated from the different instruments were Micrococcusspp, Corynebacterium spp, Bacillus sppandcoagulase-negative Staphylococcus. Conclusions: Orthophthalaldehyde was significantly more efficient as a disinfectant. The microorganisms isolated were Micrococcus spp, Corynebacterium spp, Bacillus spp and coagulase-negative Staphylococcus. Although the percentage of contaminated instruments was low in relation to the total monitored, any contaminated instrument implies risks to a patient or a professional of an infectious or contagious disease.