The effect of Sterilex UltraR for disinfection of dental unit waterlines

Abstract

Aim: To evaluate the effect of a disinfectant agent based on hydrogen peroxide (Sterilex UltraR, Sterilex Corporation, Maryland, USA) on the microbiological water quality in dental unit waterlines (DUWL). Setting: Six older dental units were disinfected with Sterilex UltraR and another six units with sodium hypochlorite. The results were compared to six nondisinfected units examined during a period without patient treatment. Outcome measure: The number of colony forming units of bacteria (cfu)/ml of water was determined according to European Standards on water quality. Design: The water quality was initially determined during a six week period, and subsequently in more detail for two weeks. Finally, the effect of prolonged administration of Sterilex UltraR was investigated for six weeks. Results: Instillation of Sterilex UltraR according to the recommendations of the manufacturer initially reduced the number of bacteria in DUWL to <102 cfu/ml. However, following daily, as well as prolonged administration of Sterilex UltraR a gradual recolonisation was observed resulting in bacterial numbers >104 cfu/ml in a number of units. Major differences between the number of cfu/ml in individual units were observed. Conclusion: Neither daily nor extended administration of Sterilex UltraR was capable of maintaining an acceptable water quality in these older dental units.