“…Of the 19 studies included, nine had a split-mouth design -six with a follow-up period of 12 months (14,16,23,27,28,34) and three with duration of over 24 months (15,35,36) -and ten had a parallel design -five with a follow-up period of 12 months (10,17,(37)(38)(39) and five with a follow-up period of over 24 months (24,25,29,40,41). Regarding the evaluated outcomes, PD and CAL were evaluated in all the studies, gingival recession (GR) was additionally evaluated in eight studies (15,16,24,25,29,36,39,41) and bone filling in twelve studies (10,(14)(15)(16)(23)(24)(25)27,29,36,39,41).…”