Comparative Evaluation of Residual Contamination on Healing Abutments after Disinfection with Sodium Hypochlorite, 2% Chlorhexidine and Autoclave: An In Vitro Study

Aims:To determine the effectiveness of sterilization on retrieved healing abutments (HAs) postdisinfection with autoclave, chlorhexidine (CHX) followed by autoclave, and sodium hypochlorite (NaOCl) followed by autoclave.Materials and methods: About 48 new HAs (BIOLINE) retrieved from patients were categorized into three groups of 16 samples each: group I-disinfection done by using NaOCl solution for 10 minutes followed by autoclave sterilization at 132C for 7 minutes; group II-disinfection done by using CHX mouthwash for 10 minutes followed by autoclave sterilization at 132C for 7 minutes; group III-samples were directly sterilized by autoclave.All the samples were then incubated in sodium thioglycolate growth media for 10 days, after which they were put on blood agar plates and again incubated for 48 hours aerobically, followed by counting the number of colonies formed.Data were recorded and statistically analyzed. Results:The mean of colony-forming units was 3.7 10 3 for the NaOCl group, 4.3 10 3 for the CHX group, and 6.64 10 3 for the autoclave alone group.Group III was found to be significantly higher (6.64 10 3 ) as compared to group I (3.7 10 3 ). Conclusion:The treatment of HAs with NaOCl followed by steam autoclaving was found to be the most effective method of removing contaminants and debris when compared to CHX followed by autoclave or autoclave alone.Clinical significance: Microbial colonies that remain viable following routine sterilization protocols have a significant impact on the transmission of infection and healing of soft tissues; hence, the most effective disinfection method must be considered and weighed against the minor economic benefits of the reuse of HAs.