Introduction Dental care has become a challenge for healthcare associated infection prevention programs, since the environment, within other factors, plays an important role in the transmission chain. Materials and Methods An intervention program was designed for the Dental Unit of Hospital Militar de Santiago, between years 2014 and 2015. The program contemplated 3 stages: diagnostic, intervention and evaluation stage. Objective To improve the safety of critical surfaces involved in dental healthcare. Results During the diagnostic stage, the cleaning and disinfection process was found to be deficient. The most contaminated critical surface was the instrument holder unit, then the clean area and lamp handle. The surfaces that significantly reduced their contamination, after the intervention, were the clean area and the instrument carrier unit. Conclusion Training in the processes of cleaning and disinfecting surfaces and dental equipment is one of the cost-effective strategies in preventing healthcare-associated infections (HCAI), with simple and easy-to-apply methods.