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The aim of this study was to evaluate the effects of leukocyte- and platelet-rich fibrin (L-PRF) on the pain and soft tissue healing after tooth extractions. Twenty-six patients (9 males and 17 females) were treated with multiple extractions (2 to 8), with a total of 108 extractions. This was an exploratory single blinded randomized clinical trial with a split-mouth design. The pain after the surgery was assessed in each patient by the VAS scale (1 to 10) at intervals of 24-48-72-96 hours. The soft tissue healing was clinically evaluated at 3, 7, 14, and 21 days after surgery by the same examiner surgeon, using the modified Healing Index (4 to 12). The mean value of postextraction pain was 3.2 ± 0.3 in the experimental sides and 4.1 ± 0.1 in the control sides. After 7 days from the extractions, the values of modified Healing Index in the experimental and control groups were, respectively, 4.8 ± 0.6 and 5.1 ± 0.9. The use of L-PRF in postextraction sockets filling can be proposed as a useful procedure in order to manage the postoperative pain and to promote the soft tissue healing process, reducing the early adverse effects of the inflammation.

Platelet derivatives are commonly used in wound healing and tissue regeneration. Different procedures of platelet preparation may differentially affect growth factor release and cell growth. Preparation of platelet-rich fibrin (PRF) is accompanied by release of growth factors, including platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF) and transforming growth factor β1 (TGFβ1), and several cytokines. When compared with the standard procedure for platelet-rich plasma (PRP), PRF released 2-fold less PDGF, but >15-fold and >2-fold VEGF and TGFβ1, respectively. Also, the release of several cytokines (IL-4, IL-6, IL-8, IL-10, IFNγ, MIP-1α, MIP-1β and TNFα) was significantly increased in PRF-conditioned medium (CM), compared to PRP-CM. Incubation of both human skin fibroblasts and human umbilical vein endothelial cells (HUVECs) with PRF-derived membrane (mPRF) or with PRF-CM enhanced cell proliferation by >2-fold (p<0.05). Interestingly, PRP elicited fibroblast growth at a higher extent compared to PRF. At variance, PRF effect on HUVEC growth was significantly greater than that of PRP, consistent with a higher concentration of VEGF in the PRF-CM. Thus, the procedure of PRP preparation leads to a larger release of PDGF, as a possible result of platelet degranulation, while PRF enhances the release of proangiogenic factors.

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No abstract

The application of BPBM, with or without a collagen membrane, can be a viable and stable treatment to alleviate the periodontal defects that are often associated with impacted mandibular third molar extractions.

Leukocyte- and platelet-rich fibrin (L-PRF) is a biomaterial commonly used in periodontology and implant dentistry to improve healing and tissue regeneration, particularly as filling material in alveolar sockets to regenerate bone for optimal dental implant placement. The objective of this work was to evaluate the use of L-PRF as a safe filling and hemostatic material after dental extractions (or avulsions) for the prevention of hemorrhagic complications in heart surgery patients without modification of the anticoagulant oral therapy. Fifty heart surgery patients under oral anticoagulant therapy who needed dental extractions were selected for the study. Patients were treated with L-PRF clots placed into 168 postextraction sockets without modification of anticoagulant therapy (mean international normalized ratio  =  3.16 ± 0.39). Only 2 patients reported hemorrhagic complications (4%), all of which resolved a few hours after the surgery by compression and hemostatic topical agents. Ten patients (20%) showed mild bleeding, which spontaneously resolved or was resolved by minimal compression less than 2 hours after surgery. No case of delayed bleeding was reported. The remaining 38 patients (76%) showed an adequate hemostasis after the dental extractions. In all cases, no alveolitis or painful events were reported, soft tissue healing was quick, and wound closure was always complete at the time of suture removal one week after surgery. The proposed protocol is a reliable therapeutic option to avoid significant bleeding after dental extractions without the suspension of the continuous oral anticoagulant therapy in heart surgery patients. Other applications of the hemostatic and healing properties of L-PRF should be investigated in oral implantology.

Autologous platelet gel (AGP) is a source of concentrated growth factors contained in the platelet granules used to enhance bone quality and, especially, quicken bone formation in regeneration techniques, and also ameliorate the haemostasis in anti-coagulated patient management. The purpose of this study is to describe a technique to perform labelling of autologous platelet-gel with 111In -Oxine and to evaluate its usefulness, as a marker of bone osteoinduction by means of scintigraphy, after in vivo application in patients with jaw bone defects following cystic lesion enucleation and the extraction of deeply impacted lower third molar. All patients included in the study presented mandible bone defects following cyst enucleation or deeply impacted lower third molar extraction. In sterile conditions, 111In-Oxine AGP was added during the bone-milling phase of the graft preparation and then applied to the bone defects. The scintigraphy was performed 2 hours after the application of labelled AGP (early scan) and at 24, 48, 72, 384 hours (delayed scan). At early scan all the patients presented a high concentration of 111In-Oxine AGP, which was easily recognized at the level of jaw defect. Limited diffusion of AGP was seen in the tissue surrounding the bone defect; this activity was attributed to the presence, in the PRP, of a quote of autologous granulocytes, as marker of inflammatory process, which was labelled with 111In-Oxine. In order to demonstrate the persistence and stability of labelling AGP, abdominal scintigraphies were performed to assess the presence of activity in the liver, spleen and bone marrow. None of the patients presented appreciable activity in these organs. The labelled AGP topically applied showed high uptake values, without statistically significant activity in the surrounding tissues or in critical organs during the early phase, as well as in delayed controls, and confirmed a very low grade of loss of 111In-Oxine from the bone defect. The scintigraphy represents a useful method of assessing the success of surgical procedure for jaw bone defects performed with autogenous grafts. It is well accepted by the patients, offering at the same time a sensitive method of studying uptake of topically applied AGP and to follow up kinetics of AGP in order to correlate quantitative data of the platelet gel life span with evolution of the bone remodelling process. Finally, the labelled granulocytes around the bone defect allow to assess the inflammatory process evolution derived from the surgical technique.