Comparison of the Effectiveness of Preprocedural Rinse and Ultrasonic Coolant using Chlorhexidine Gluconate and Povidoneiodine in Reducing Aerosol Contamination: A Randomised Clinical Trial

Abstract

Introduction: The production of airborne particles with embedded microorganisms poses a high risk to dental professionals. Antimicrobials, when used in various forms such as pre-procedural rinse or ultrasonic coolant agents, could reduce the aerosol load. Aim: To compare the effectiveness of ultrasonic coolant, preprocedural rinse using 0.2% Chlorhexidine (CHX) gluconate, and 2% Povidone-iodine (PVI) in reducing aerosol contamination. Materials and Methods: A prospective single-centre, triple-blind, randomised clinical trial was conducted in the Department of Periodontology at Sree Sai Dental College and Research Institute, Srikakulam, India. The study duration was four months, from November 2021 to February 2022. A total of 75 patients diagnosed with gingivitis, aged 20 to 30 years, systemically healthy, with probing depths of <3 mm were included and randomly assigned to one of two groups: pre-procedural rinse or ultrasonic cooling agent. They were then divided into five subgroups: Subgroup I - CHX pre-procedural rinse, Subgroup II - PVI pre-procedural rinse, Subgroup III - ultrasonic cooling agent CHX, Subgroup IV - ultrasonic cooling agent PVI, and Subgroup V - control (distilled water). Agar plates were placed at three different locations, followed by a 20-minute ultrasonic scaling procedure. The agar plates were then incubated at 37°C for 48 hours, and the Colony Forming Units (CFU) were counted using a digital colony counter. Multiple measures Analysis of Variance (ANOVA) was performed for group-wise comparisons, and Tukey’s post-hoc test was performed for intergroup comparison of CFU. Results: All the groups reported statistically significant differences. The control group had higher CFU (616.85, 871.77, 342.23 for the operator, patient, and back of the patient’s head, respectively) compared to the rinse and coolant groups. However, the CHX coolant group showed lower CFU (186.31±41.508 at the operator’s chest area, 415.38±59.219 at the patient’s chest area, 71.69±10.323 at the back of the patient’s head) compared to the other subgroups. The patient’s chest area had higher CFUs (415.38±59.219 for CHX coolant, 545.85±38.105 for PVI coolant group, 580.38±48.290 for CHX rinse group, 752.46±41.667 for PVI rinse group, 871.77±98.826 for the control group) compared to the blood agar plates placed at other locations. Conclusion: The results of the study clearly indicate that CHX coolant can be considered a promising alternative in reducing aerosol contamination produced during ultrasonic scaling procedures.