Matarasso 1998.

Methods	RCT, parallel design, 2 treatment groups, 12 months' duration
Participants	20 individuals, 8 females, aged 18 to 42 years, with 1 Miller Class I or II buccal gingival recession of at least 3 mm
Interventions	1. GTR (polylactic acid membrane ‐ Guidor) + double papilla flap 2. GTR (polylactic acid membrane ‐ Guidor) + CAF
Outcomes	GRC CALC KTC MRC (Manual probe)
Notes	University/hospital‐based Unpublished data were included following contact with author
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method not reported
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	High risk	All measurements were performed by 1 examiner aware of the type of surgical procedure
Incomplete outcome data (attrition bias) All outcomes	Low risk	All patients completed the follow‐up period
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