Narayana 2016.

Study characteristics
Methods	Trial design: CCT – split mouth (multi‐arm) Location: G Pulla Reddy Dental College, Kurnool, Andhra Pradesh, Oxford Dental College, Bangalore, India Setting: good ventilated room measuring about 20 feet × 15 feet with single dental chair Language: English Number of centres: 2 Study period: not mentioned Funding source: not mentioned Study protocol: not available
Participants	Age: not given Total number of participants: 15 (for HVE group) Inclusion criteria: patients undergoing supragingival scaling Exclusion criteria: immunocompromised patients or patients with systemic diseases Method of randomization: not mentioned Method of allocation concealment: not mentioned Method of blinding: not mentioned Number evaluated (withdrawals/missing participants): 15 (no dropouts)
Interventions	Comparison: HVE versus no HVE Intervention: Group A: with and without preprocedural rinse with 0.12% chlorhexidine rinse Group B: with and without HVE Group C: with and without preprocedural rinse with 0.12% chlorhexidine rinse and HVE Group name: Group B: 2nd and 3rd quadrant – with HVE Number of intervention groups: 1 Number of participants in the intervention group: 15 Description of intervention: Group B consists of 15 individuals with 1st and 4th quadrants undergoing supragingival scaling without HVE, 2nd and 3rd quadrants undergoing supragingival scaling with HVE. Any co‐interventions: no (2 other group was present Group A ‐ with and without preprocedural rinse and Group C – combination) Comparator: Group name: Group B: 1st and 4th quadrant ‐ without HVE Number of control groups: 1 Number of participants in the control group: 15 Description of control: Group B consists of 15 individuals with 1st and 4th quadrants undergoing supragingival scaling without HVE, 2nd and 3rd quadrants undergoing supragingival scaling with HVE.
Outcomes	Outcome name: reducing bioaerosol contamination during ultrasonic scaling procedure (blood agar plates were used to check CFU) Outcome measurement: CFU Effect estimate: mean (SD not given) Key conclusions: CFU were significantly reduced with the use of HVE in Group B individuals.
Notes	We contacted the study authors for: SD and study protocol. E‐mail sent on 18 June 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)	High risk	Controlled clinical trial
Allocation concealment (selection bias)	High 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	Unclear risk	It is not clear if the CFU were manually counted or any automated colony counters were used – there is subjectivity if manually counted.
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