Silvestri 2000.

Methods	1‐year follow‐up parallel‐group study including 3 groups with 30 patients in total. No drop outs at 1 year.
Participants	Patients in good general health and motivated for good oral hygiene. Teeth with PPD greater or equal to 6 mm and IBD greater or equal to 4 mm. Smokers were excluded. Age ranging between 37 and 59; 11 males and 19 females recruited in 1 university dental clinic and several private practices.
Interventions	Emdogain versus GTR with Gore‐Tex non‐resorbable barriers versus flap surgery.
Outcomes	FMPS and FMBS. For experimental teeth only: PAL, PPD, REC at baseline and 1 year. Tooth loss and postoperative infections. 1‐year data used.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Once the patients met on all entry criteria, they were randomly (Fleiss 1992) assigned to 1 of 3 surgical procedures".
Allocation concealment (selection bias)	High risk	Author informed us that group allocation was not concealed.
Blinding (performance bias and detection bias) All outcomes	High risk	Author informed us that no blinding method was used.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Outcome data for PAL, PPD and REC are presented in Table 1. Comment: No missing data. No drop outs.
Selective reporting (reporting bias)	Low risk	All the pre‐specified outcomes are reported in Table 1. No teeth were extracted. Aesthetics and changes in bone level were not evaluated.
Other bias	Unclear risk	Manufacturers partially supported the trial by offering free materials. We do not think that this has affected the outcome of the trial. Connective tissue grafts were placed in 6 patients after membrane removal. We are unsure whether this affected the outcome of the trial.