Study	Reason for exclusion
Agarwal 2017	Mixed design ‐ randomised controlled trial
Aleksić 2008	No randomisation
Aroca 2009	Gingival recession (not infrabony defects)
Bajaj 2017	Mixed design ‐ randomised controlled trial
Camargo 2002	No control group
Camargo 2005	No control group
Cetinkaya 2014	Same participants of Keles 2006
Chatterjee 2017	Mixed design ‐ randomised controlled trial
Cheung 2004	Autologous platelet concentrates not the only difference between groups
Cieplik 2018	Incomplete data
Cortellini 1995	No platelet concentrate (fibrin glue)
Dogan 2015	Gingival recession (not infrabony defects)
Döri 2013	Same participants of Döri 2008b
Eren 2014	Autologous platelet concentrates not the only difference between groups
Gupta 2014b	Non‐independence of analysis unit
Harnack 2009	Incomplete data
Huang 2005	Gingival recession (not infrabony defects)
Jankovic 2010	Gingival recession (not infrabony defects)
Jankovic 2012	Autologous platelet concentrates not the only difference between groups
Jovicić 2013	No randomisation
Keceli 2008	Incomplete data
Keles 2006	Incomplete data
Lekovic 2012	No control group
Menezes 2012	Incomplete data
Moder 2012	Same participants of Christgau 2006
Ouyang 2006	Mixed design ‐ randomised controlled trial
Padma 2013	Gingival recession (not infrabony defects)
Pradeep 2012a	Non‐independence of analysis unit
Pradeep 2017	Mixed design ‐ randomised controlled trial
Qiao 2016	Mixed design ‐ randomised controlled trial
Saini 2011	No randomisation
Shah 2015	Incomplete data
Shepherd 2009	Gingival recession (not infrabony defects)
Shivakumar 2016	Gingival recession (not infrabony defects)
Thamaraiselvan 2015	Gingival recession (not infrabony defects)
Trombelli 1995	No platelet concentrate (fibrin glue)
Trombelli 1996	No platelet concentrate (fibrin glue)
Yajamanya 2017	Same participants of Chatterjee 2017
Yassibag‐Berkman 2007	Incomplete data
Yen 2007	Incomplete data