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Updated: Mar 21, 2026

Biofilm Removal Using Carbon Dioxide Aerosols without Nitrogen Purge
Published on: November 6, 2016
Role of preprocedural rinse and high volume evacuator in reducing bacterial contamination in bioaerosols
T V Narayana1, Leeky Mohanty2, G Sreenath3
1Head of Oral and Maxillofacial Pathology, Independent Dental Practitioner, Impressions Dental Car, Elegant Desire Building No 1, Coles Road, Frazer Town, Bangalore, India.
Context:
Microbial contamination, which occurs during dental procedures, has been a potential threat to dental professionals and individuals. There has been a growing concern over the role of bioaerosols in spread of various airborne infections and also to reduce the risk of bioaerosol contamination.
Aims:
This study was to analyze the number of colony forming units (CFUs) in bioaerosols generated during ultrasonic scaling procedure as well as to evaluate the efficacy of chlorhexidine 0.12% (CHX) preprocedural mouth rinse and high volume evacuator (HVE) in minimizing the bioaerosol contamination.
Methods:
About 45 individuals were divided into three Groups A, B and C. These groups underwent ultrasonic scaling before and after the use of CHX (0.12%), HVE and combination of CHX (0.12%) and HVE. Bioaerosols were collected on blood agar plates which were incubated at 37°C for 48 h, and the CFUs were counted with manual colony counting device. A comparison was also done between A versus B, B versus C and A versus C groups.
Statistical Analysis Used:
Student's t-test.
Results:
We found a significant reduction in the CFUs when CHX (0.12%) preprocedural rinse (P < 0), or HVE (P < 0.001) or combination of both CHX (0.12%) and HVE were employed (P < 0.001). Maximum reduction in CFUs was observed when CHX (0.12%) and HVE were used in combination as compared to their individual use. A moderate significance was seen between A versus C groups but not with B versus C groups and A versus B groups.
Conclusion:
From our study, we conclude that individual methods such as CHX (0.12%) and HVE were useful to reduce the dental bioaerosols; however, combination of both CHX (0.12%) and HVE is more efficient to reduce dental bioaerosols than individual method.
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