Comparison of the Effects of Injectable Platelet-rich Fibrin and Low-dose Laser Applications on Palatal Wound Healing.

Attached gingiva plays an important role in maintaining periodontal health. In the presence of insufficient attached gingiva, inflammation and root sensitivity, root caries and gingival recessions that cause esthetic complaints occur in periodontal tissues due to mucogingival stress in the relevant region and inadequate oral hygiene. In such cases, the width of insufficient attached gingiva should be increased with mucogingival periodontal plastic surgery procedures. Free gingival graft (FGG) is accepted as the most frequently used mucogingival surgical procedure to increase attached gingiva due to the predictability of the surgical result, simplicity of the technique and its applicability in wide operation areas including many teeth. In the FGG operation, a recipient bed is prepared in the region with insufficient attached gingiva. A free gingival graft containing epithelium and connective tissue is applied from the donor region in appropriate dimensions to this recipient bed. The palatal region is the most preferred donor area in terms of anatomical advantage, ideal tissue thickness and wide keratinized band harvest . The secondary wound formed in the donor area after FGG heals in 2-4 weeks and can cause many problems affecting patient comfort . Different products such as hemostatic agents, herbal products, ozonated oil, antibacterial and antiseptic agents, bioactive materials and platelet concentrates have been tested to accelerate wound healing and prevent these problems. Studies are ongoing to determine the product and method that provides optimal patient comfort and wound healing after surgery from these products known to have effects on wound healing.

Palatal donor area healing occurs with fibroblast proliferation, collagen synthesis, angiogenesis and wound contraction. Revascularization, immune system and epithelial cell proliferation are very important for optimal wound healing. It has been reported that platelet concentrates used in palatal wound healing accelerate wound healing and reduce postoperative patient discomfort by releasing growth factors such as transforming growth factor β (TGF-β), platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and insulin-like growth factor-1 (IGF-1). Platelet-rich fibrin (PRF) has a three-dimensional fibrin network, and this structure and growth factor release enhance cell proliferation, migration, angiogenesis, and wound healing. The use of PRF in the palatal donor site after FGG surgery has been shown to provide significant benefits in terms of wound healing parameters and postoperative comfort. In recent years, there has been a need for an injectable formulation of PRF without the use of anticoagulants. This need was met with the introduction of a new platelet concentrate, Injectable platelet-rich fibrin (i-PRF), by Joseph Choukroun in 2014. I-PRF is obtained by centrifuging blood at low speed (700 rpm, 60 G). This concentrate is the injectable form of PRF and clots within a few minutes after injection. It is believed to contain not only white blood cells and platelets but also circulating stem cells and endothelial cells. Therefore, it is considered not only a platelet concentrate but also a "blood concentrate".

It has been reported that low-dose laser therapy has many areas of use in periodontal soft and hard tissues such as gingivitis, periodontitis, dentin sensitivity, gingivectomy and gingivoplasty, free gingival graft, guided tissue regeneration and peri-implantitis treatment and that it contributes positively to wound healing . The stimulating effects of low-dose laser therapy at the cellular level are based on the increase in blood flow in the damaged area and the formation of new capillaries, and faster healing of the tissue as a result of more oxygen supply. In addition, advantages such as increased cell respiration and Adenosine Triphosphate (ATP) synthesis, increased venous and lymphatic flow, collagen synthesis, anti-inflammatory effect and analgesic effect, stimulation of wound healing, immune system modulation, increased periodontal tissue attachment, increased bone regeneration, and reduced inflammatory status in periodontal pockets have been reported .

The investigators believe that the findings obtained as a result of the study will help determine the method that contributes the most to wound healing. Although there are many studies in the literature on low-dose laser and platelet concentrates in palatal wound healing, this study is the first to compare the contribution of 980 nm low-dose laser and i-PRF application to wound healing after FGG operations.