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Updated: Aug 20, 2025

Characterization of Leukocyte-platelet Rich Fibrin, A Novel Biomaterial
Published on: September 29, 2015
Effectiveness of using platelet-rich fibrin to increase keratinized tissue around the tooth in the modified apical
Parviz Torkzaban1, Nazli Rabienejad1, Zahra Cheraghi2
1Department of Periodontology, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
Objectives:
One of the simplest methods to increase keratinized gingiva is the modified apically repositioned flap (MARF) technique. In this method, the periosteum remains exposed, which may lead to postoperative pain and discomfort. In the presence of bone dehiscence, bone resorption and gingival recession may occur. Hence, this study aims to use platelet-rich fibrin (PRF) to promote wound healing in the MARF technique and overcome its disadvantages.
Material And Methods:
In this randomized controlled trial study, 10 patients (six males and four females with a mean age of 33.9 ± 11.13) with less than 2 mm of attached gingiva bilaterally were treated by the MARF + PRF membrane (test group), on the one hand, whereas, on the other hand, it was treated only by MARF (control group). Clinical parameters of keratinized gingiva include thickness, width, and vestibule depth before and 8 weeks after the intervention were measured.
Results:
The attached gingival width increased significantly in both groups (1.7 mm in the MARF and 2.3 mm in the PRF) and this was greater in the PRF group (p < .05). Gingival thickness in the PRF method was significantly higher than in the control group (p < .05). Probe depth, vestibular depth, and postoperative pain were not different in both groups. Wound shrinkage in the MARF group (51%) was significantly higher than in the PRF group (30%) (p < .05).
Conclusion:
Using PRF with the MARF method significantly increased the width and thickness of the gingiva and reduced shrinkage compared to MARF only. Postoperative pain and vestibular depth changes were similar in both groups.
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