Impact of local and systemic antimicrobials on leukocyte- and platelet rich fibrin: an in vitro study.

The aim of this study was to evaluate the effect of local and systemic administration of antimicrobials to leukocyte- and platelet-rich fibrin (L-PRF). For part A, 16 tubes of venous blood were collected from each of eight systemically healthy subjects. Prior to blood centrifugation, 12 of the 16 tubes were injected with 0.125 ml, 0.25 ml or 0.50 ml metronidazole solution. One set of L-PRF membranes was used to assess the release of vascular endothelial growth factor AB, platelet-derived growth factor, transforming growth factor beta 1, and bone morphogenetic protein 2 at indicated time points. The metronidazole release over time by L-PRF membranes was also evaluated. The remaining L-PRF membranes were placed on the surface of agar plates inoculated with three different periodontal pathogens to determine their antibacterial activity. For part B, another six subjects were enrolled with three subjects taking 2 g amoxicillin and three subjects 500 mg metronidazole as prophylaxis prior to a periodontal treatment. Before and 2 h after consuming one of the prescribed antimicrobials, three tubes of blood were collected for preparing L-PRF membranes. These membranes were used to measure the antibacterial activity against periodontal pathogens. No statistically significant difference could be found in the release of growth factors between L-PRF membranes with and without incorporation of metronidazole solution. The release of metronidazole could be detected up to day 3, however with the highest concentration during the first 4 h. This concentration was dose dependent. The antibacterial capacity of L-PRF membranes increased significantly for both the systemic intake, and after the addition of metronidazole solution to the blood tubes before centrifugation, the latter again dose dependent. The antibacterial capacity of L-PRF against the periodontal pathogens tested can significantly be enhanced by the addition of antimicrobials, without disadvantage for the release of growth factors.

Impact of Zoledronic Acid and Denosumab Treatment on Growth Factor Concentration in Platelet Rich Fibrin of Patients With Osteolytic Bone Metastases.

BACKGROUND/AIM: Side effects of zolendronic acid (ZA) and RANKL inhibitors (RANKL-I) include impaired wound healing and osteonecrosis of the jaw. Platelet rich fibrin (PRF) enhances wound healing and bone remodelling in vivo and in vitro. However, the topical use PRF in the surgical treatment of patients with medicament-related osteonecrosis of the jaw is relatively new and not thoroughly investigated. Furthermore, the potential attenuation of the PRF effect following antiresorptive treatment remains unclear. Therefore, we investigated the concentration of growth factors within the PRF in healthy volunteers and in patients with antiresorptive treatment. PATIENTS AND METHODS: Blood samples from healthy volunteers and patients were used to produce PRF. The levels of EGF, VEGF, PDGF-BB, TGF-ß1, BMP-2, and CD31 in the PRF was investigated by ELISA. RESULTS: ZA treatment induced a significant decrease in EGF and TGF-ß1 levels, whereas RANKL-I caused lower TGF-ß1 levels. CONCLUSION: Reduced EGF levels in PRF after ZA treatment may explain the delayed wound healing and question the positive effect of PRF in these patients. PRF use in patients undergoing RANKL-I treatment seems to be more justified.

Utilização de membranas de L-PRF junto à instalação de implantes unitários em área anterior de maxila: estudo clínico randomizado / Use of L-PRF membranes in single implants installation in anterior maxilla area: randomized clinical trial

Para evitar a ocorrência de defeitos de tecido mole ao redor de implantes, um volume adequado de tecido (ósseo e mole) deve estar presente. Uma segunda geração de concentrado de plaquetas, denominada fibrina rica em plaquetas e leucócitos (L-PRF), foi desenvolvida na França. Pesquisas têm mostrado resultados positivos com o uso de L-PRF durante a colocação de implantes, melhorando a cicatrização dos tecidos moles e a osseointegração. O objetivo deste estudo foi avaliar se o uso de membranas de L-PRF associado à colocação de implantes unitários em área anterior de maxila gera aumento da espessura do tecido mole. Vinte e sete pacientes com indicação para instalação de implante unitário na região foram divididos aleatoriamente entre grupo teste (implante + L-PRF, n=14) e grupo controle (implante, n=13). Os procedimentos cirúrgicos foram realizados por um único operador. A espessura do tecido mole foi avaliada clinicamente previamente ao tratamento cirúrgico e após três meses da cirurgia. Os resultados mostraram que neste tempo de acompanhamento houve ganho na espessura do tecido mole vestibular ao implante (1,86±0,49 mm para 2,49±0,51 mm), bem como redução do defeito do rebordo na região (1,82±0,77 mm para 1,18±0,89 mm) no grupo teste. Não houve diferença significativa intragrupo no grupo controle para nenhum dos parâmetros avaliados. Concluiu-se que o uso de membranas de L-PRF gerou aumento da espessura de tecido mole quando associado à colocação de implante unitário em área anterior de maxila(AU)

To prevent the occurrence of soft tissue defects around implants, an adequate amount of bone and soft tissue volume should be present. A second generation of platelet concentrate, named Leucocyte and platelet-rich fibrin (PRF), was developed in France. Research has shown positive results with the use of PRF during implant placement, improving soft tissue healing and osseointegration. The aim of this study was to evaluate whether the use of L-PRF membranes associated with implant placement in anterior maxilla presents an increase in soft tissue thickness. Twentyseven patients requiring single implant placement in the area were randomly divided into test group (implant + L-PRF, n=14) and control group (implant, n=13). Surgical procedures were performed by a single operator. Soft tissue thickness was clinically assessed at baseline and 3 months after surgery. The results showed that, at this time of follow-up, there was a gain in vestibular soft tissue thickness (1.86 ± 0.49 mm to 2.49 ± 0.51 mm), as well as a reduction in the buccal bone defect in the region (1.82 ± 0.77 mm to 1.18 ± 0.89 mm) in the test group. There was no significant intragroup difference in the control group for any of the evaluated parameters. It was concluded that the use of L-PRF membranes can lead to an increase in soft tissue thickness when associated with a single implant placement in the anterior maxilla area(AU)

Tissue preservation through socket-shield technique and platelet-rich fibrin in immediate implant placement: A case report.

RATIONALE: In this report, a combination of socket-shield technique (SST) and platelet-rich fibrin (PRF) technique was used for immediate implant placement on a fractured central incisor. During the follow-up visit, cone beam computed tomography (CBCT) and clinical observation were used to evaluate the preservation outcome of peri-implant bone and gingiva. PATIENT CONCERNS: The patient was a 28-year-old healthy female patient who desired her fractured 21 to be replaced with an implant-supported single crown; the fractured 21 comprised a post-core crown with insufficient residual bone at the labial site. DIAGNOSIS: The root of 21 exhibited a complex root fracture; the labial portion of the alveolar ridge was thin (<1 mm) and partial ankylosis of the residual root was observed. INTERVENTIONS: Modified SST was applied to the labial portion of the residual root. The implant was placed immediately at the lingual site of the retained socket-shield root fragment; PRF was the placed in the gap between the root fragment and the implant. Final prosthodontic treatment was performed at 24 weeks after implant placement. OUTCOMES: Clinical examination and CBCT scanning at various follow-up visits time showed that the periodontal tissue was well- preserved. At 6 months after surgery, the average horizontal and vertical peri-implant bone resorption was 0.4 mm; a follow-up visit at 18 months post-loading indicated that peri-implant tissue was well preserved by the shield-technique and no significant peri-implant tissue resorption was displayed. LESSON SUBSECTIONS: In cases of anterior teeth with intact but insufficient residual alveolar ridge, the SST with PRF may be effective for preservation and maintenance of stable peri-implant tissue.

Bone regeneration around immediate placed implant of molar teeth with autologous platelet-rich fibrin: Two case reports.

RATIONALE: There are some challenges concerning immediate implant placement in molar region. Platelet-rich fibrin (PRF), a second generation platelet concentrate, is an autologous fibrin matrix and contains platelets, growth factors, and leukocytes. It is used for tissue healing and regeneration in periodontal and oral-maxillofacial surgery. We report 2 cases of immediate placed implant of molar teeth with autologous PRF to improve and accelerate tissue healing. PATIENT CONCERNS: Case 1 was a 38-year-old female patient with masticatory discomfort. Case 2 was a 43-year-old male patient with a demand for his left mandibular posterior tooth restoration. DIAGNOSES: Through the clinical and radiographic examination, the patient in case 1 was diagnosed with vertical root crown fracture of the maxillary right first molar. The patient in case 2 was diagnosed with residual root of the left mandibular first molar via cone-beam computer tomography and clinical examination. INTERVENTIONS: The 2 patients underwent extraction of the molar teeth and immediate placed implant of molar teeth with autologous PRF was performed. In case 1, the gap between the implant surface and the socket walls of freshly extracted tooth was filled with PRF mixed with a commercial spongious bone substitute, followed by 2 PRF membranes coverage for protection. In case 2, PRF was used as a sole bone substitute material, placed between immediate implant and the socket wall of freshly extracted tooth. OUTCOMES: Follow-up of 2 cases revealed successful osseointegration and matured gingiva with optimal form and function. LESSONS: The results suggested that PRF could solely serve as a bone scaffold in 4-wall bony defects, or can be combined with xenograft in 3-wall bony defects during immediately placed implants in molar regions, exhibiting excellent biocompatibility and good soft and hard tissue healing.

Comparison of the clinical, radiographic, and histological effects of titanium-prepared platelet rich fibrin to allograft materials in sinus-lifting procedures.

AIM: In the present study, we evaluated the clinical, radiographic, and histological comparisons of completely autologous titanium-prepared platelet rich fibrin (T-PRF) or allograft in sinus-lifting procedures. METHODS: Eighteen posterior maxilla requiring sinus-lifting procedures using the balloon-lifting technique for implant placement were selected. Ten sinuses were randomly assigned to T-PRF as the test group and eight to allografts as the control group. After 4 and 6 months in the test and control groups, respectively, computed tomography was done, and bone samples were received during implant surgery. Three months after the second surgery, implant stability was measured. RESULTS: Radiological results showed that the allograft group had better results (62% in volume, 53% in density, and 69% in height) than the T-PRF group. Histomorphometric results showed that newly-formed bone ratios were 17.28 ± 2.53 and 16.58 ± 1.05 in the allograft group and T-PRF groups, respectively. There was no significant difference between the test and control groups (P = .611) for implant stability values. CONCLUSIONS: The use of T-PRF alone in sinus-lifting operations has successful clinical and histomorphometric results. Bone formation in the T-PRF group was accelerated to 4 months compared to allografts according to the histological results.

Platelet-Rich Fibrin Accelerates Skin Wound Healing in Diabetic Mice.

Diabetic foot ulcers (DFUs) are associated with an increased risk of secondary infection and amputation. Platelet-rich fibrin (PRF), a platelet and leukocyte concentrate containing several cytokines and growth factors, is known to promote wound healing. However, the effect of PRF on diabetic wound healing has not been adequately investigated. The aim of the study was to investigate the effect of PRF on skin wound healing in a diabetic mouse model. Platelet-rich fibrin was prepared from whole blood of 8 healthy volunteers. Two symmetrical skin wounds per mouse were created on the back of 16 diabetic nude mice. One of the 2 wounds in each mouse was treated with routine dressings (control), whereas the other wound was treated with PRF in addition to routine dressings (test), each for a period of 14 days. Skin wound healing rate was calculated.Use of PRF was associated with significantly improved skin wound healing in diabetic mice. On hematoxylin and eosin and CD31 staining, a significant increase in the number of capillaries and CD31-positive cells was observed, suggesting that PRF may have promoted blood vessel formation in the skin wound. In this study, PRF seemed to accelerate skin wound healing in diabetic mouse models, probably via increased blood vessel formation.