Jawade 2016.

Study characteristics
Methods	Trial design: RCT – parallel, 3 arms Location: MIDSR Dental College, Latur, Maharashtra, India. Setting: closed dental operatory Language: English Number of centres: 1 Study period: July 2015 to October 2015 Funding source: not mentioned Study protocol: not available
Participants	Age: 22 to 55 years Total number of participants: 30 participants (10 per group) (17 male, 13 female) Inclusion criteria: minimum of 20 permanent functional teeth, and mean probing depth ≤ 5 mm and clinical attachment loss ≤ 3 mm measured with Williams Periodontal Probe (Hu‐Friedy) in at least 30% teeth sites Exclusion criteria: a history of systemic diseases like diabetes mellitus, hypertension, rheumatoid arthritis, etc, use of tobacco in any form, history of periodontal treatment in the preceding 6 months, pregnant and lactating females, thyroid dysfunction, use of antibiotic or other drugs that affect periodontal status in the preceding 6 months or allergic to chlorhexidine and povidone iodine Number randomized: 30 (10 per group) Number evaluated (withdrawals/missing participants): 30 (none)
Interventions	Comparison: antimicrobial coolant A (povidone iodine) versus antimicrobial coolant B (chlorhexidine gluconate) Intervention: Group name: Group 2 (test group): ultrasonic scaling with 2% povidone iodine in 0.1% dilution (10 participants) 2% povidone iodine is diluted in 1:1 ratio in 1 litre water to prepare ultrasonic liquid coolant Group 3 (test group): ultrasonic scaling with 0.12% chlorhexidine in 0.06% dilution (10 participants) 0.12% chlorhexidine gluconate is diluted in 1:1 ratio in 1 litre water to prepare ultrasonic liquid coolant Number of intervention groups: 2 Number randomized to intervention group: 10 per group Description of intervention: ultrasonic scaling was carried out for 20 minutes by the clinician, with universal tip attached to the ultrasonic scaler. The normal rate of flow of water in ultrasonic scaler is 20 to 30 ml/min. The same rate of flow of water for each agent (2% povidone iodine in 0.1% dilution and 0.12% chlorhexidine in 0.06% dilution) while performing ultrasonic scaling was maintained. To assure that the room was free from aerosols, only 1 person was treated per day. For every scaling procedure, high‐vacuum suction was used. After the treatment, 3 coded blood agar plates were left uncovered for 20 minutes at the pre‐designated sites for gravitometric settling of airborne bacteria. After gravitometric settling of aerosols, blood agar plates were transferred to laboratory for incubation at 37 °C for 48 hours followed by colony counting procedure with the help of colony counter device by the microbiologist. Any co‐interventions: no Comparator: Group name: Group 1 (control group): ultrasonic scaling with distilled water (10 participants) Number of control groups: 1 Number randomized to control group: 10 Description of control: as described above except that the ultrasonic coolant was distilled water
Outcomes	Outcome name: reduction in contamination of aerosol (positions selected for agar plates was 0.4 metres on right, 0.4 metres on left and 2 metres behind the participant) Outcome measurement: CFU (using blood agar plates) Effect estimate: mean (SD) Key conclusions: this study indicates that chlorhexidine gluconate as an ultrasonic liquid coolant significantly reduces the microbial content of dental aerosols generated during scaling when compared with distilled water. Chlorhexidine gluconate showed better CFU reductions when compared with povidone iodine. Povidone iodine also showed better CFU reduction when compared with distilled water.
Notes	Study author were contacted for: allocation concealment, blinding and study protocol. E‐mail sent on 26 July 2020 and we are yet to receive any response from the contact author.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: “All subjects were assigned to one of the three groups by using randomization table...” Method of randomization: randomization table
Allocation concealment (selection bias)	Unclear risk	No details given
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Blinding is not possible. However, participants and personnel will not be able to alter their behaviour even if they know the received intervention.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "After gravitometric settling of aerosols, blood agar plates were transferred to laboratory for incubation at 37°C for 48 hours followed by colony counting procedure with the help of colony counter device by the microbiologist."
Incomplete outcome data (attrition bias) All outcomes	Low risk	No dropouts
Selective reporting (reporting bias)	Unclear risk	We are not sure of reporting selective outcomes as there is no protocol available.
Other bias	Low risk	None