Costa 2016.

Methods	RCT, split‐mouth design, 2 treatment groups, 6 months' duration
Participants	20 individuals (heavy smokers ‐ 10 or more cigarettes/day for over 5 years), 12 females, aged 30 to 50 years, with 2 bilateral Miller Class I or II buccal gingival recessions of at least 3 mm
Interventions	1. ADMG + EMD + CAF (extended flap) 2. ADMG + CAF (extended flap)
Outcomes	GRC*(1) CALC KTC SCRC PCRC MRC (Automated controlled force probe and compass)
Notes	University/hospital‐based
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "method of randomly allocating by simple draw"
Allocation concealment (selection bias)	Unclear risk	Method not reported
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Information not reported
Blinding of outcome assessment (detection bias) All outcomes	Low risk	All measurements were performed by 1 examiner not aware of the type of surgical procedure
Incomplete outcome data (attrition bias) All outcomes	Low risk	1 patient did not return for clinical evaluation at 6 months Data are equally missing in both intervention groups (split‐mouth design), but reasons for these are both reported and balanced across groups, then important bias is not be expected
Selective reporting (reporting bias)	Low risk	Evidence of selective reporting of outcomes was not detected
Other bias	Low risk	Evidence of other bias was not detected