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Is platelet concentrate advantageous for the surgical treatment of periodontal diseases? A systematic review and meta-analysis.

BACKGROUND
The aim of the present review is to systematically evaluate the effects of autogenous platelet concentrates on clinical outcomes of the surgical treatment of periodontal diseases.


METHODS
MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched using a combination of specific search terms. Furthermore, a hand search of relevant journals and bibliographies of reviews was performed. Only randomized clinical trials were included. For periodontal intrabony defects, the primary outcome variable was the clinical attachment level. For gingival recession, outcome variables were root coverage and keratinized tissue increase. Data were adjusted for baseline values. The methodologic quality of the included studies was assessed. The results of studies in which the only difference between test and control groups was the adjunct of platelet concentrates were aggregated using a meta-analysis. For intrabony defects, the influences of guided tissue regeneration (GTR) and study type (split-mouth versus parallel studies) were also evaluated.


RESULTS
The initial search yielded 424 studies. Of the 29 eligible studies, 24 studies were included. There were 16 studies on the treatment of periodontal intrabony defects, all of which used platelet-rich plasma (PRP); six studies on gingival recession treatment; and two studies on the treatment of furcation defects. A significant positive effect of the adjunct of PRP was found for intrabony defects. Such an effect was magnified in studies in which GTR was not used, whereas in studies using GTR, the use of PRP had no adjunctive effect. No effect of the study type was found. No significant effect of platelet concentrates was found for gingival recession treatment in which only studies with a follow-up ≤6 months displayed positive results. No significant benefit of PRP could be demonstrated for furcation treatment.


CONCLUSIONS
PRP may exert a positive adjunctive effect when used in combination with graft materials, but not with GTR, for the treatment of intrabony defects. No significant benefit of platelet concentrates was found for the treatment of gingival recession.