The aim of this randomized clinical trial was to clinically evaluate and compare the healing of intrabony defects after treatment with advanced platelet-rich fibrin (A-PRF+) to enamel matrix derivatives (EMD) in periodontitis patients.

Thirty (30) intrabony defects of 18 patients (9 males, 9 females) were randomly divided in two treatment groups: test (n = 15) and control (n = 15). The intrabony defects were filled with A-PRF+ (n=15) in the test group, respectively with EMD in the control group, and fixed with sutures to ensure wound closure and stability.

Inclusion Criteria:

• no systemic diseases that could influence the outcome of the therapy, a good level of oral hygiene, he presence of a 2-, 3-, or combined 2-3-wall intrabony defect with a defect angle of 20-40 (+/- 5) degrees, with a minimum PPD of 6 mm and intrabony component of a minimum 4 mm as detected on radiographs, no smoking

Exclusion Criteria:

• systemic diseases that could influence the outcome of the therapy, poor oral hygiene, smoking, horizontal bone loss