Gutta percha cone disinfection efficiency analysis

Vol. 11 – Number 43 – 2020 CLINICAL DENTISTRY NOTEBOOK Original article Page 80-85 Gutta percha cone disinfection efficiency analysis Vivian Dinardi Rocha¹ Luiza Cristina Ribeiro Melo¹ Paola Bernardes¹ Leandro Maruki Pereira² Paulo Vinicius Rocha Pereira³ Fernando Fachilnelli Rodrigues³ Eduardo Silva Botelho² ABSTRACT This study aims to evaluate disinfection effectiveness of different substances (alcohol 70%, chlorhexidine 2%, sodium hypochlorite 2.5%, and 0.9% physiological solution used as positive control) and periods (10, 60, 180, and 300 seconds) used for decontamination of gutta percha cones. For this, 160 gutta percha cones were initially contaminated in BHI broth containing Eschechiria coli (ATCC35218) for 72 hours. After incubation, they were divided into 16 groups (n =10) according to the solution and time used, immersed in the tested solutions for four different periods, and then each cone was immersed in a tube containing 3ml of sterile BHI broth and incubated again for 24 hours. After this period, 1ml was collected from each substance and the interferometry analysis was performed. The concentration of the collected broth was compared to that of a sterile broth and the difference was determined as broth contamination. Data were submitted to the analysis of Variance test (a= 0.05) and Tukey test (a=0.05). All samples disinfected with 70% alcohol presented contamination, regardless of time; among the samples disinfected with 2% chlorhexidine, two presented contamination in each time analyzed, except for the time of 300 seconds. All samples disinfected with 2.5% NaClO showed decontamination regardless of the time analyzed. According to this study, NaClO 2.5% presented the best efficacy for surface decontamination, being the most suitable for gutta percha cones. Descriptors: Gutta percha, disinfection, chlorhexidine, sodium hypochlorite. ¹ Undergraduates – Faculty of Dentistry – UNIPAM. ² Prof. undergraduate course in Dentistry – UNIPAM. ³ Prof. undergraduate course in Biomedicine – UNIPAM.