EC Dental Science

The type of microorganisms are crucial, as some are more resistant than others, such as bacterial spores compared to vegetative bacteria. The presence of organic and inorganic matter can impede disinfection by protecting microbes or neutralizing disinfectants. Proper prior cleaning of surfaces can enhance disinfectant effectiveness by reducing microbial load. Disinfectants are antimicrobial chemicals that are applied to the surfaces of inanimate objects to kill germs that live on them. The effectiveness of germicides against microorganisms is contingent upon multiple factors, including those inherent to the organism and those arising from the chemical and physical surroundings.

The concentration and contact time of the disinfectant are also vital, with higher concentrations and longer contact times generally being more effective. Surface characteristics, such as porosity, impact how well a disinfectant works, with non-porous surfaces being easier to disinfect. Additionally, environmental factors like pH and temperature play significant roles, as certain disinfectants perform better under some specific conditions. By optimizing these factors, disinfection practices can be significantly improved, ensuring higher levels of cleanliness and safety. This chapter gives an insight about factors affecting efficacy of disinfection. It will also include some basic definitions, guidelines regarding disinfection and sterilization and a quick checklist to test the effectiveness of commonly used disinfectants.

 Keywords: Disinfection; Efficacy; Factors; Disinfectants; Sterilization

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