Platelet-rich fibrin (PRF): a second-generation platelet concentrate. Part IV: clinical effects on tissue healing

Radiological assessment of the PRF/BMSC efficacy in the treatment of aseptic nonunions: A retrospective study on 90 subjects

BACKGROUND

Nonunion is a major orthopaedic concern because of treatment difficulty, high costs and devastating effects on the patients' life quality. Therefore, there is interest in the use of bone substitutes and cell-based strategies to augment fracture repair. We aimed to verify if Platelet Rich Fibrin (PRF) added with bone marrow stromal cells (BMSC) was able to improve the reparative process in the aseptic nonunion, and to establish whether it was worthwhile with atrophic nonunion. The primary outcome was radiological union. As secondary endpoint, the healing time was assessed, and the radiological consolidation grade at each follow-up.

METHODS

We identified 113 subjects with tibia or femur nonunion and retrospectively created two groups. Group A was constituted by 56 subjects who underwent the standard procedure, i.e. Judet decortication with/out internal fixation devices, and opposite cortical homoplastic stick. In 57 patients, the standard procedure was modified by adding PRF and BMSC carried by homologous lyophilised bone chips (group B). The same surgeon performed all the operations. To our knowledge, no data are reported in the literature about such application. Since a "gold standard" for healing quantification does not exist, a new scoring radiological system was applied, at 1.5, 3, 6, 12 and 24 months after treatment.

RESULTS

At the final 24-month follow-up, the radiological union percentage was 94,12 in group B and 95,12% in group A. A decreased healing time was demonstrated in the presence of PRF/BMSC in comparison with the standard procedure. When we compared the radiological scores at each follow-up, we found that the PRF/BMSC combination significantly improved the consolidation grade at 1.5-, 3- and 6-month follow-up in femurs and at 1.5-month follow-up in tibiae. Furthermore, an improved consolidation grade was demonstrated in the atrophic subjects treated with adjuvants compared to atrophic patients treated with the standard procedure at 1.5-month follow-up.

CONCLUSIONS

This study supports the concept that the use of PRF/BMSC, during the standard procedure, is effective in shortening nonunion healing time. It could allow an early mobilization of patients, minimizing suffering, and could be an effective tool to reduce the health-care costs resulting from this issue.

LEVEL OF EVIDENCE

Therapeutic level III.

Effects of Platelet-Rich Plasma & Platelet-Rich Fibrin with and without Stromal Cell-Derived Factor-1 on Repairing Full-Thickness Cartilage Defects in Knees of Rabbits

BACKGROUND

The purpose of this study was to create biomaterial scaffolds like platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) containing stromal cell-derived factor-1 (SDF1) as a chemokine to induce hyaline cartilage regeneration of rabbit knee in a full thickness defect.

METHODS

We created a full thickness defect in the trochlear groove of thirty-six bilateral knees of eighteen mature male rabbits. The knees were randomly divided into six groups (group I: untreated control, group II: PRP, group III: PRF, group IV: Gelatin+SDF1, group V: PRP+SDF1, and group VI: PRF+SDF1). After four weeks, the tissue specimens were evaluated by macroscopic examination and histological grading, immunofluorescent staining for collagen type II, and analyzed for cartilage marker genes by real-time PCR. The data were compared using statistical methods (SPSS 20, Kruskal-Wallis test, Bonferroni post hoc test and P<0.05).

RESULTS

Macroscopic evaluations revealed that international cartilage repair society (ICRS) scores of the PRF+SDF1 group were higher than other groups. Microscopic analysis showed that the ICRS score of the PRP group was significantly lower than other groups. Immunofluorescent staining for collagen II demonstrated a remarkable distribution of type II collagen in the Gel+SDF1, PRP+SDF1 and PRF+SDF1 groups compared with other groups. Real-time PCR analysis revealed that mRNA expression of SOX9 and aggrecan were significantly greater in the PRF+SDF1, PRP+SDF1, Gel+SDF1 and PRF groups than the control group (P<0.05).

CONCLUSION

Our results indicate that implantation of PRF scaffold containing SDF1 led to the greatest evaluation scores of full-thickness lesions in rabbits.

Ridge Expansion by Flapless Split Crest and Immediate Implant Placement: Evolution of the Technique

Various treatment strategies and techniques have been proposed to perform alveolar bone augmentation; most common are guided bone regeneration, split crest, and autologous bone grafting. All of these techniques are reported to possess bone regenerative properties of osteoinduction and osteoconduction in relation to regenerated bone survival. Split crest resulted to be one of the most reliable bone augmentation techniques. In this study, we describe a new flapless-modified split crest technique on 4 patients to optimize the bone regeneration with bone augmentation implant insertion in 1 single stage. The rationale of this technique is to obtain a proper buccal cortex expansion preserving its vascular supply and avoiding periosteal elevation for better cortical bone preservation. The main advantages of this technique consist in a single surgical stage without donor sites, vascular periosteal preservation of vestibular cortical walls, preservation of alveolar bone height avoiding bone loss after implant kit drilling, and preservation of proper cortical thickness on both sides, thereby saving periosteal nourishment on the vestibular side. Indication for this technique could be extended to almost every implant insertion for alveolar height saving at drilling time for implant insertion, because of the alveolar crest shape.

Custom anatomic healing abutments

Dental implants with their increasing success rates and predictability of final outcome are fast becoming the treatment of choice for replacing missing teeth. Considering the success of immediate implant placement in reducing tissue loss and achieving good esthetic results, is making it a more popular treatment modality in implant dentistry. Understanding the management of gingival tissues in relation to implants to obtain maximum esthetics is of utmost importance. The use of provisional abutments and immediate temporization has a proven track record of their ability to produce optimal esthetics and to guide the tissue response during the healing phase. With careful patient selection and execution, customized healing abutments can provide an effective method to enhance the esthetic and emergence profile for anterior implant restorations.

Platelet-Rich Fibrin and Soft Tissue Wound Healing: A Systematic Review

The growing multidisciplinary field of tissue engineering aims at predictably regenerating, enhancing, or replacing damaged or missing tissues for a variety of conditions caused by trauma, disease, and old age. One area of research that has gained tremendous awareness in recent years is that of platelet-rich fibrin (PRF), which has been utilized across a wide variety of medical fields for the regeneration of soft tissues. This systematic review gathered all the currently available in vitro, in vivo, and clinical literature utilizing PRF for soft tissue regeneration, augmentation, and/or wound healing. In total, 164 publications met the original search criteria, with a total of 48 publications meeting inclusion criteria (kappa score = 94%). These studies were divided into 7 in vitro, 11 in vivo, and 31 clinical studies. In summary, 6 out of 7 (85.7%) and 11 out of 11 (100%) of the in vitro and in vivo studies, respectively, demonstrated a statistically significant advantage for combining PRF to their regenerative therapies. Out of the remaining 31 clinical studies, a total of 8 reported the effects of PRF in a randomized clinical trial, with 5 additional studies (13 total) reporting appropriate controls. In those clinical studies, 9 out of the 13 studies (69.2%) demonstrated a statistically relevant positive outcome for the primary endpoints measured. In total, 18 studies (58% of clinical studies) reported positive wound-healing events associated with the use of PRF, despite using controls. Furthermore, 27 of the 31 clinical studies (87%) supported the use of PRF for soft tissue regeneration and wound healing for a variety of procedures in medicine and dentistry. In conclusion, the results from the present systematic review highlight the positive effects of PRF on wound healing after regenerative therapy for the management of various soft tissue defects found in medicine and dentistry.

Mandibular Degree II Furcation Defects Treatment With Platelet-Rich Fibrin and 1% Alendronate Gel Combination: A Randomized Controlled Clinical Trial

BACKGROUND

Different materials have been investigated for renewal of lost supporting periodontal structures and tested for furcation defect treatment. Platelet-rich fibrin (PRF) is a pool of growth-promoting factors and cytokines that promote bone regeneration and maturation of soft tissue. Alendronate (ALN), an influential member of the bisphosphonate group, is known to enhance osteoblastogenesis and inhibit osteoclastic bone resorption, thus promoting tissue regeneration. This randomized trial was done to assess effectiveness of PRF and 1% ALN gel combination in mandibular degree II furcation defect treatment in comparison with PRF and access therapy alone.

METHODS

Seventy-two mandibular molar furcation defects were treated with either access therapy alone (group 1), access therapy with PRF (group 2), or access therapy with PRF and 1% ALN (group 3). Plaque index, modified sulcus bleeding index, probing depth (PD), relative vertical attachment level (RVAL) and relative horizontal attachment level (RHAL), and intrabony defect depth were recorded at baseline and 9 months postoperatively. Radiographically, defect fill, assessed in percentage, was evaluated at baseline, before surgery, and 9 months post-therapy.

RESULTS

Group 3 showed greater PD reduction and RVAL and RHAL gain when compared with groups 1 and 2 postoperatively. Moreover, group 3 sites showed a significantly greater percentage of radiographic defect fill (56.01% ± 2.64%) when compared with group 2 (49.43% ± 3.70%) and group 1 (10.25% ± 3.66%) at 9 months.

CONCLUSIONS

Furcation defect treatment with autologous PRF combined with 1% ALN gel results in significant therapeutic outcomes when compared with PRF and access therapy alone. Combining ALN with PRF has potential for regeneration of furcation defects without any adverse effect on healing process.

The role of titanium-prepared platelet-rich fibrin in palatal mucosal wound healing and histoconduction

OBJECTIVE

We aimed to determine the clinical effects of titanium-prepared, platelet-rich fibrin (T-PRF) on human palatal mucosal wound healing (PMWH) and to identify its effect on time-dependent changes in palatal soft-tissue thickness (PSTT) in terms of histoconduction, which is a new concept.

MATERIALS AND METHODS

Free gingival graft (FGG) donor sites were treated with T-PRF and compared with an untreated control group. The results of colour match and H₂O₂-bubbling tests for complete wound epithelization (CWE) were recorded on days 3, 7, 14 and 21. Pain level, number of analgesics used and bleeding status were recorded for the first 7 days. PSTT was measured at baseline and after 1 and 6 months.

RESULTS

Colour match scores of the test group were significantly higher than those of the control group at 7 and 14 days. CWE was observed at a higher frequency in the test group than in the control group on day 14. Post-operative bleeding prevalence was lower in the test group than in the control group for the first 2 days. A time-dependent decrease in PSTT was observed at 1 and 6 months in the control group compared with baseline (baseline, 4.23 ± 0.62 mm; 1 month, 4.01 ± 0.68 mm; and 6 months, 3.93 ± 0.69 mm). However, no significant difference was found in the test group (baseline, 4.29 ± 0.64 mm; 1 month, 4.61 ± 0.51 mm; and 6 months, 4.51 ± 0.58 mm).

CONCLUSION

The T-PRF membrane exhibited positive effects on PMWH. T-PRF, which is a promising autogenous matrix for histoconduction, may also be preferred as an autogenous alternative to connective tissue grafts in the treatment of gingival recessions and peri-implant mucosal recessions.

Platelet-rich fibrin (PRF) in implant dentistry in combination with new bone regenerative technique in elderly patients

•

PRF in association with a new split crest augmentation technique was analyzed.

•

Ten patients five with the new technique and five by traditional one were treated.

•

All cases were successful and all implants achieved osteointegration.

•

Main advantages with this technique are soft tissues healing and bone regenerative properties.

Introduction

Some studies have demonstrated that platelet rich fibrin (PRF) is a healing biomaterial with a great potential for bone and soft tissue regeneration, without any inflammatory reactions and may be used alone or in combination with bone grafts, promoting hemostasis, bone growth, and maturation. PRF appears as a natural and satisfactory aid in bone regenerative surgery in elderly patients with favorable results and low risks.

Aim

This study wants to demonstrate how PRF in association with a new split crest augmentation technique can be a great aid in implant rehabilitation, especially in the elderly patients, when bone regeneration is required.

Materials and methods

Ten patients were treated in this study, five following the flapless split crest new procedure and other five patients following traditional procedure without split crest as control. Five patients with an average age between 50 and 60 years were selected to be operated with a split crest flapless modified technique in order to optimize the regenerative conditions with a bone augmentation and implant insertion in one single stage procedure. For all the patients autologous PRF has been used to fill the split crest gap or simply as regenerative material. Orthopantomography, intraoral radiography and CT DentaScan/CT Cone beam were performed for every patient before the treatment and at follow-up time exeption made for CT.

Results

All cases were successful, there were no problems at surgery time, at post-operative and at osteointegration periods. All implants achieved osteointegration. These results were obtained by accurately managing immediate and late post operative period in all of the operated cases. Mean difference for height bone loss between the two groups of patients was 2.4 mm at T1 and 2.2 mm at T3.

Discussion

The rationale of this split crest flapless modified technique is to obtain a proper buccal cortex expansion preserving its vascular supply avoiding periosteal elevation for better cortical bone nourishing. Moreover, advantages are reported related to the use of PRF. The effectiveness of PRF is shown in promoting the healing of surgical wounds, it has, in fact, platelet growth factors that can improve the vascularisation of the surgical site, promoting neoangiogenesis. Furthermore, by simply changing the settings of the centrifuge, it is possible to obtain a normal gelling if it has to be used as regenerative and stimulating material, or more consistent substance to be used as a filler in the split crest gap.

Conclusions

The main advantages in using the platelet-rich fibrin are healing and bone regenerative properties in combination with its complete resorption after surgery, thus avoiding a second surgery time, important factor in the elderly patients. Currently, it is a minimally invasive technique with low risks and satisfactory clinical results such preventing complications or implant failure particularly in elderly patients for age related conditions.

Positive effect of platelet rich fibrin on osseointegration

Background

Leukocyte-platelet rich fibrin (L-PRF) is a second generation platelet concentrate clinically used to accelerate tissue healing and bone regeneration. Achieving reduced implant osseointegration time could provide immediate or early loading of implants. The aim of this study was to evaluate the L-PRF-induced osseointegration and bone-implant contact (BIC) in an experimental animal model.

Material and Methods

Twelve 4-month-old New Zealand white rabbits were used. Following general anesthesia, 3-5 mL of blood was obtained from the central artery in rabbit ear and L-PRF was prepared. Two implant cavities (5 mm long and 3 mm in diameter) were created in each tibia with a total of four cavities in each animal. Two of these cavities were selected and covered with PRF (test group). The remaining L-PRF was used to soak the implants placed into the L-PRF covered sockets. Other cavities were left as controls. In total, 48 implants were placed. Animals were sacrificed after two, three, or four weeks. Histological samples were obtained and peri-implant tissues were histomorphometrically evaluated for bone-to-implant contact and new bone formation.

Results

Histomorphometric analyses of the defects revealed that the L-PRF was detectable up to the second week. Application of L-PRF increased the rate and amount of new bone formation in the experimental group compared to the control group. Bone-to-implant contact was enhanced when the surface was pre-wetted with L-PRF (p<0.01).

Conclusions

The results of this study demonstrated that L-PRF application may increases amount and rate of new bone formation during the early healing period and provides a faster osseointegration around implants.

Key words:Dental implants, platelet rich fibrin, osseointegration, bone regeneration, matrix for growth factors.

Synergistic Approach Using Platelet-Rich Fibrin and 1% Alendronate for Intrabony Defect Treatment in Chronic Periodontitis: A Randomized Clinical Trial

BACKGROUND

Platelet-rich fibrin (PRF) is a reservoir of concentrated platelets that provides a pool of biologic growth-promoting factors and cytokines, which help in mediating regeneration of lost bone and soft tissue maturation. Alendronate (ALN), a member of the amino-bisphosphonate group, is known to enhance periodontal tissue regeneration by inhibiting osteoclast-mediated bone resorption and promoting osteoblast-mediated osteogenesis. The current intervention aims to assess combined effectiveness of PRF and 1% ALN with access therapy in intrabony defect (IBD) treatment in patients with chronic periodontitis (CP).

METHODS

Single IBDs in 90 patients were categorized into three groups: 1) group 1 had access therapy alone; 2) group 2 had access therapy with PRF; and 3) group 3 had access therapy with PRF + 1% ALN. Site-specific plaque index, modified sulcus bleeding index, probing depth (PD), clinical attachment level (CAL), and gingival marginal level, included as parameters for clinical assessment, were evaluated before surgery at baseline and 9 months postoperatively. Percentage IBD depth reduction, assessed using radiographs, was evaluated at baseline and postoperatively.

RESULTS

Compared with groups 1 and 2, group 3 exhibited significantly greater reduction in PD and gain in CAL postoperatively. Significantly greater IBD depth reduction was shown in group 3 (54.05% ± 2.88%) compared with group 2 (46% ± 1.89%) and group 1 (7.33% ± 4.86%) postoperatively.

CONCLUSION

Combined approach therapy of PRF + 1% ALN for IBD treatment in patients with CP showed better clinical parameter outcomes with greater IBD depth reduction compared with PRF and access therapy alone.

Platelet-Rich Fibrin With 1.2% Rosuvastatin for Treatment of Intrabony Defects in Chronic Periodontitis: A Randomized Controlled Clinical Trial

BACKGROUND

Regenerative periodontal therapy encompasses use of various bioactive agents that are not only inflammomodulatory but also osteoclast-inhibitory or, rather, osteostimulative. Hypolipidemic statin drugs, particularly rosuvastatin (RSV), are known to be associated with alveolar bone formation and periodontal improvements. Platelet analogs such as platelet-rich fibrin (PRF), being rich sources of growth factors, have also come into widespread periodontal regenerative use. The aim of this study is to evaluate and compare efficacy of open flap debridement (OFD) with or without PRF or PRF + 1.2% RSV gel in treatment of intrabony defects (IBDs) in patients with chronic periodontitis (CP).

METHODS

Ninety individuals with a total of 90 IBDs were randomly assigned to one of three treatment groups: 1) OFD alone; 2) OFD + PRF; and 3) OFD + PRF + 1.2% RSV gel placement. Measurements recorded at baseline and 9 months after surgery were: 1) plaque index (PI); 2) modified sulcus bleeding index (mSBI); 3) probing depth (PD); 4) clinical attachment level (CAL); and 5) IBD depth.

RESULTS

Significant PI and mSBI reductions were observed in all three groups. PRF placement significantly enhanced improvements in periodontal parameters compared with OFD alone. Addition of 1.2% RSV gel to PRF resulted in significantly greater CAL gain and PD and IBD depth reductions over 9 months compared with other groups.

CONCLUSION

OFD with RSV (1.2%) and PRF results in significantly greater periodontal benefits compared with OFD alone or with PRF.

Early Bone Formation at a Femur Defect Using CGF and PRF Grafts in Adult Dogs: A Comparative Study

PURPOSE

The purpose of this study was to compare the predictability of new bone formation using an autologous concentrated growth factor (CGF) graft alone and platelet graft alone.

MATERIALS AND METHODS

Four bony defects of 8 mm were formed, and 3.7- × 10-mm implants were placed in the right femur. The platelet-rich fibrin (PRF), CGF, and synthetic bone were grafted to the bone defect area. Enzyme linked immunosorbent assay quantitative analysis and microscopic analysis of the fibrinogen structure were performed.

RESULTS

At 4 weeks, the comparisons of each experimental group showed a significant difference between the CGF group and the synthetic bone graft group. When comparing the CGF and allograft material groups, the allograft group showed significantly more new bone formation. In the case of vascular endothelial growth factor, CGF had 1.5 times more than PRF. CGF showed a fibrinogen structure with a constant diameter.

CONCLUSION

When applied to a clinical case, CGF is predicted to show better results than PRF.

Platelet Rich Fibrin in Periodontal Regeneration

Periodontitis is a chronic bacterial infection resulting in destruction of the supporting structures of the teeth. Regeneration of the lost tissues has faced difficulties primarily due to the lack of support during the intricate healing processes. A surgical additive which can 'jump start' the healing process to a more predictable regenerative process is always on the wish list of any periodontist. Platelet-rich fibrin (PRF) is a second generation platelet concentrate that has been considered to be an important, easy to obtain, predictable surgical additive for periodontal regeneration. This autologous scaffold provides the much needed bio-chemical mediators which has the potential for enhancing reconstruction of the periodontium. This review article tries to understand as to why PRF would be an important link to reach predictable periodontal regeneration.

The effect of PRF (platelet-rich fibrin) inserted with a split-flap technique on soft tissue thickening and initial marginal bone loss around implants: results of a randomized, controlled clinical trial

Background

Previous studies have shown that adequate thickness or initial augmentation of soft tissue has a positive effect on the stability of peri-implant bone. This randomized, controlled trial aimed to evaluate the influence of augmenting soft tissue with platelet-rich fibrin (PRF) on crestal bone and soft tissue around implants.

Methods

After randomization, 31 fully threaded titanium implants were inserted in 31 patients (16 men and 15 women) in the lower mandible using a split-flap technique. In the test group (10 patients), mucosa was treated with a PRF membrane. In the control group (21 patients), implantation was realized without soft tissue augmentation. Tissue thickness was measured at point of implant insertion (baseline) and at time of reentry after 3 months. Standardized digital radiographs were obtained for evaluation at time of implant placement, reentry after 3 months and at a 6-month follow-up. Data was analyzed by an independent examiner.

Results

After 6 months, all 31 implants were osteointegrated. Soft tissue augmentation with PRF led to a significant tissue loss. In the test group, the crestal tissue thickness dropped from 2.20 mm ± 0.48 SD at baseline to 0.9 mm ± 1.02 SD at reentry, whereas crestal mucosa in the control group showed higher stability (2.64 mm ± 0.48 SD at baseline to 2.62 mm ± 0.61 SD at reentry). For ethical reasons, the test group was terminated after 10 cases, and the remaining cases were finished within the control group. In the test group, radiographic evaluation showed a mean bone loss of 0.77 mm ± 0.42 SD/0.57 mm ± 0.44 SD (defect depth/defect width) on the mesial side and 0.82 mm ± 0.42 SD/0.62 mm ± 0.36 SD (defect depth/defect width) on the distal side. In the control group, a mean bone loss of 0.72 mm ± 0.61 SD/0.51 mm ± 0.48 mm (defect depth/defect width) on the mesial and 0.82 mm ± 0.77 SD/ 0.57 mm ± 0.58 SD (defect depth /defect width) on the distal side was measured.

Conclusions

Within the limits of this study and the early determination of the test group, this study concludes that soft tissue augmentation with PRF performed with a split-flap technique cannot be recommended for thickening thin mucosa. Further studies focusing on different techniques and longer follow-ups are needed to evaluate whether PRF is suitable for soft tissue thickening.

Cryogenically salvaged teeth as a potential source for grafting dentoalveolar, periodontal or maxillofacial defects

Bone grafting uses a wide range of materials derived mainly from exogenous sources. Autogenous teeth are often used fresh or fixed with alcohol for later use. Proposed here is a method of using cryogenically preserved autogenous extracted teeth, which could be macerated after thawing. This method avoids the possibility of tissue being denatured by alcohol and preserves intact all calcified structures for optimal bone grafting success.

Flapless transcrestal sinus augmentation using hydrodynamic piezoelectric internal sinus elevation with autologous concentrated growth factors alone

PURPOSE

The purpose of this retrospective study was to evaluate the success rate of implants and the amount of sinus augmentation using the flapless hydrodynamic piezoelectric internal sinus elevation (HPISE) technique with autologous concentrated growth factors (CGF) alone.

MATERIALS AND METHODS

A total of 11 maxillary sinuses were augmented using the HPISE technique through the flapless transcrestal approach. Sixteen implants (average 11.38 mm in length and 4.83 mm in diameter), with 2 different surfaces, were placed simultaneously with CGF alone. Plain panoramic radiograms and cone-beam computed tomograms (CBCT) were taken in all patients to evaluate the sinus augmentation preoperatively and postoperatively.

RESULTS

The sinus membranes were successfully elevated, averaging 13.95 ± 6.61 mm in immediate postoperative CBCT without any iatrogenic perforation. After an average 23.8 weeks, the average bone gain above the sinus floor was 8.23 ± 2.88 mm in the axial aspect of CBCT. No complications were recorded in any patients during the follow-up period.

CONCLUSION

The flapless transcrestal approach to the sinus augmentation using the HPISE technique with autologous CGF alone could be an alternative to the lateral approach, even at severely resorbed edentulous posterior maxilla with insufficient bone height.

Use of leukocyte and platelet-rich fibrin (L-PRF) in periodontally accelerated osteogenic orthodontics (PAOO): Clinical effects on edema and pain

Background

Demand for shorter treatment time is common in orthodontic patients. Periodontally Accelerated Osteogenic Orthodontics (PAOO) is a somewhat new surgical procedure which allows faster tooth movement via combining orthodontic forces with corticotomy and grafting of alveolar bone plates. Leukocyte and Platelet-Rich Fibrin (L-PRF) possess hard- and soft-tissue healing properties. Further, evidence of pain-inhibitory and anti-inflammatory potential is growing. Therefore, this study explores the feasibility, intra- and post-operative effects of using L-PRF in PAOO in terms of post-operative pain, inflammation, infection and post-orthodontic stability.

Material and Methods

A pilot prospective observational study involving a cohort of 11 patients was carried out. A Wilcko’s modified PAOO technique with L-PRF (incorporated into the graft and as covering membrane) was performed with informed consent. Post-surgical pain, inflammation and infection were recorded for 10 days post-operatively, while the overall orthodontic treatment and post-treatment stability were followed up to 2 years.

Results

Accelerated wound healing with no signs of infection or adverse reactions was evident. Post-surgical pain was either “mild” (45.5%) or “moderate” (54.5%). Immediate post-surgical inflammation was either “mild” (89.9%) or “moderate” (9.1%). Resolution began on day 4 where most patients experienced either “mild” or no inflammation (72.7% and 9.1%, respectively). Complete resolution was achieved in all patients by day 8. The average orthodontic treatment time was 9.3 months. All cases were deemed stable for 2 years.

Conclusions

L-PRF is simple and safe to use in PAOO. Combination with traditional bone grafts potentially accelerates wound healing and reduces post-surgical pain, inflammation, infection without interfering with tooth movement and/or post-orthodontic stability, over a 2 years period; thus alleviating the need for analgesics and anti-inflammatory medications.

Key words:Periodontally accelerated osteogenic orthodontics, leukocyte and platelet-rich fibrin, corticotomy, osteogenesis, grafts.

Comparative evaluation of platelet-rich fibrin, mineral trioxide aggregate, and calcium hydroxide as pulpotomy agents in permanent molars with irreversible pulpitis: A randomized controlled trial

Background:

Pulpotomy has been proposed as an alternative for the management of irreversible pulpitis in permanent molars with closed apices.

Aim:

To compare the performances of calcium hydroxide (CH), mineral trioxide aggregate (MTA), and platelet-rich fibrin (PRF) as pulpotomy agents in mature permanent molars with irreversible pulpitis.

Materials and Methods:

Fifty-four permanent mandibular molars with carious exposure and symptoms of irreversible pulpitis were randomly allocated to three groups, and full pulpotomy was performed using CH_, MTA, or PRF as pulpotomy agents. Pain intensity was recorded using numeric rating scale score at baseline, 24 h, 7 days, 6 months, and 1 year. Clinical and radiographic assessments were done at 6 months and 1 year.

Statistical Analysis:

Kruskal–Wallis test and Friedman test were used for intergroup and intragroup comparison of pain scores, respectively. The radiographic outcomes between the three study arms were compared using Chi-square test.

Results:

Clinical success rate was 94.4% at 7 days, which dropped to 85.4% at 12 months. All three agents were equally effective in providing pain relief at all the intervals tested, with no significant difference between them (P > 0.05 at all intervals). However, at 6 months and 12 months, 26.2% and 52.4% teeth depicted slight widening of periodontal ligament space. No significant difference was observed between the radiographic success rates observed with the three groups (P = 0.135 at 6 months, 0.717 at 12 months).

Conclusion:

Pulpotomy exhibited a high clinical success rate in mature molars with irreversible pulpitis and selection of biomaterial did not affect its outcome.

Clinical and Histologic Evaluation of Platelet-Rich Fibrin Accelerated Epithelization of Gingival Wound

The foremost indication for gingival depigmentation is patient demand for improved aesthetics. In most cases after the removal of pigmented layer, the area is covered with periodontal packs. These dressings have no curative properties. They only minimise the likelihood of surface trauma during mastication. However, platelet-rich fibrin (PRF) accelerates wound healing by effective neovascularisation and promoting fast cicatricial tissue remodelling. In the present split mouth study, PRF membrane was applied in the first quadrant and non-eugenol dressing (Coe-Pack) in the second quadrant after depigmentation. Clinical evaluation of epithelization with toluidine blue revealed that PRF treated sites stained substantially less indicating better wound healing as compared to Coe-Pack sites, which appeared more erythematous after 5 days. The histologic evaluation also revealed greater inflammatory cell infiltrate on Coe-Pack sites as compared to PRF. Thus, PRF membrane as a periodontal dressing is a successful approach to protect the raw wound area of the depigmented site to reduce healing time and patient discomfort.

Concentrated growth factor increases Schwann cell proliferation and neurotrophic factor secretion and promotes functional nerve recovery in vivo

Concentrated growth factor (CGF) is a newly generated complex that comprises a fibrin matrix incorporating growth factors and plasmatic and leukocyte cytokines. It has been widely used in bone regenerative medicine. However, the effect of CGF on peripheral nerve regeneration had not been previously investigated. The aim of the present study was to evaluate the possibility of using CGF for nerve regeneration by i) investigating the effect of CGF on the proliferation of Schwann cells (SCs) and secretion of neurotrophic factors nerve growth factor (NGF) and glial cell line‑derived neurotrophic factor (GDNF) in vitro; and ii) analyzing the effect of CGF on functional nerve recovery after nerve injury in vivo. CGF was prepared from venous blood taken from rats, and using scanning electron microscopy (SEM) we noted that it featured a fiber‑like appearance with pore size ranging from 0.1 to 1.0 µm. The soluble component of CGF was used to produce conditioned media with which to treat the Schwann cell line. A cell counting kit-8 assay and cell cycle analysis were both used to study the proliferative effect of CGF on SCs. Reverse transcription-quantitative PCR and western blot analysis demonstrated that there was an increase in the mRNA and protein expression of NGF and GDNF, both of which are markers of SC neurotrophic secretion. A model of sciatic nerve crush injury was established for the in vivo experiment, and CGF was found to increase the sciatic functional index (indicative of nerve function). We noted that CGF increased SC proliferation and secretion of neurotrophic factors in vitro, and promoted functional recovery after peripheral nerve injuries in vivo. These results suggest that CGF is a promising candidate biomaterial for peripheral nerve regeneration, and may potentially be utilized to repair nerve injuries.

Surgical re-entry evaluation of regenerative efficacy of bioactive Gengigel(®) and platelet-rich fibrin in the treatment of grade II furcation: A novel approach

The furcation area creates situations in which routine periodontal procedures are somewhat limited, and surgical procedures are generally required. The introduction of bioactive agents, such as platelet concentrates, enamel matrix derivatives, bone morphogenic proteins, and matrix macromolecules such as hyaluronic acid has expanded the scope for better outcomes in furcation treatment. Hyaluronic acid is a naturally occurring nonsulfated high molecular weight glycosaminoglycan that forms a critical component of the extracellular matrix and contributes significantly to tissue hydrodynamics, cell migration, and proliferation. Platelet-rich fibrin (PRF) is an immune and platelet concentrate containing all the constituents of a blood sample, which are favorable for healing and immunity. The purpose of the present case report was to assess through surgical re-entry, the regenerative capacity of Gengigel^® in conjunction with PRF in a patient with grade II furcation defect. It was observed that the combined approach resulted in significant furcation defect fill on re-evaluation at 6 months.

Efficacy of platelet rich fibrin in the reduction of the pain and swelling after impacted third molar surgery: randomized multicenter split-mouth clinical trial

Background

Impacted third molar removal is a routine procedure in oral and maxillofacial surgery. Platelet-rich fibrin (PRF) is a second generation platelet concentration which is produced by simplified protocol. The aim of this study was to assess the effectiveness of PRF in the healing process by evaluating the changes in pain and swelling after third molar surgery.

Methods

Fifty-six patients (23 male, 33 female) who provide the inclusion criteria were selected to participate in this study. The evaluation of the facial swelling was performed by using a horizontal and vertical guide. The pain was evaluated in the postoperative period using a visual analog scale (VAS) of 100 mm.

Results

Horizontal and vertical measurements showed more swelling at the control side (without PRF) in 3th day postoperatively (p < 0.05). There were no statistically significant differences regarding pain among the groups.

Conclusion

As a conclusion, PRF seems to be effectiveness on postoperative horizontal swelling after third molar surgery. PRF could be used on a routine basis after third molar extraction surgery.

Management of apicomarginal defect in esthetic region associated with a tooth with anomalies

Tooth related factors such as palatoradicular groove can be one of the causes for localized periodontal destruction. Such pathological process may result in apicomarginal defect along with inflammation of pulp. This creates challenging situation which clinician must be capable of performing advanced periodontal regenerative procedures for the successful management. This case report discusses clinical management of apicomarginal defect associated with extensive periradicular destruction in a maxillary lateral incisor, along with histopathologic aspect of the lesion.

Use of Platelet-Rich Fibrin Membrane in the Treatment of Gingival Recession: A Systematic Review and Meta-Analysis

BACKGROUND

The aim of this systematic review is to evaluate the effects of platelet-rich fibrin (PRF) membranes on the outcomes of clinical treatments in patients with gingival recession.

METHODS

Articles that were published before June 2015 were searched electronically in four databases without any date or language restrictions and searched manually in regular journals and unpublished studies. The eligibility criteria comprised randomized controlled trials (RCTs) and prospective controlled trials with follow-up periods of ≥ 6 months that compared the performance of PRF to other biomaterials in the treatment of Miller Class I or II gingival recessions. For the meta-analysis, the inverse variance method was used in fixed- or random-effect models, which were chosen according to heterogeneity. The estimates of the intervention effects were expressed as the mean differences in percentages or millimeters.

RESULTS

Six RCTs and one prospective clinical trial are included in this review. Root coverage (RC) and clinical attachment level (CAL) did not differ significantly between the analyzed subgroups (P = 0.57 and P = 0.50, respectively). The keratinized mucosa width (KMW) gain was significantly greater (P = 0.04) in the subgroup that was treated with connective tissue grafts.

CONCLUSION

The results of the meta-analysis suggest that the use of PRF membranes did not improve the RC, KMW, or CAL of Miller Class I and II gingival recessions compared with the other treatment modalities.

A comparison of efficiency of biopolymer and allograft matrix with autogenous gingival graft used in root coverage procedure

Severe surgical techniques have been introduced to augment gingival tissue dimensions like the free gingival graft, free connective grafts, etc., However, both the techniques are associated with significant patient morbidity due to the secondary surgical site. In order to overcome these postsurgical complications, acellular dermal allografts have been used as a substitute for the palatal donor tissue yielding clinically comparable results. However, the cost and origin of the material raises concern regarding the frequent use of the material. As an improved alternative to above-mentioned graft material, the use of platelet-rich fibrin (PRF) and collagen matrices has been promoted in the recent past. The objective of this illustrative case report is to test the efficacy of collagen matrix, PRF to augment attached gingiva and to assess the esthetic outcome when compared to the standard treatment with free autogenous graft.

Soft tissue regeneration using leukocyte-platelet rich fibrin after exeresis of hyperplastic gingival lesions: two case reports

INTRODUCTION

Leukocyte-platelet rich fibrin belongs to a second generation of platelet concentrates that does not need biochemical blood manipulation. It is used for tissue healing and regeneration in periodontal and oral-maxillofacial surgery. We report two cases of hyperplastic gingival lesions treated by exeresis and application of leukocyte-platelet rich fibrin membranes in order to improve and accelerate tissue healing.

CASE PRESENTATION

Two patients (a 78-year-old Caucasian woman and a 30-year-old Caucasian man) were treated for hyperplastic gingival lesions. They underwent to exeresis of lesions and application of leukocyte-platelet rich fibrin membranes. Tissue healing was clinically evaluated after 1, 3, 7, 14 and 30 postoperative days. No recurrences were observed after 2 years of semi-annual follow up.

CONCLUSIONS

We obtained rapid and good healing of soft tissues probably due to the elevated content of leukocytes, platelets and growth factors in the leukocyte-platelet rich fibrin. Based on our results we suggest the use of leukocyte-platelet rich fibrin to cover wounds after exeresis of oral neoformations such as hyperplastic gingival lesions.

Quantification of platelets obtained by different centrifugation protocols in SHR rats

OBJECTIVE

To quantify the platelet concentration in the blood of SHR rats, by means of different centrifugation protocols, and to evaluate what the most effective method for obtaining platelets is.

METHODS

We used 40 male rats of the isogenic SHR lineage. The animals were divided into three groups: control, using whole blood without centrifugation; single centrifugation, using whole blood subjected to a single centrifugation at 200 × g and 400 × g; and double centrifugation, using whole blood subjected one centrifugation at different rotations, followed by collection of whole plasma subjected to another centrifugation at different rotations: 200 × g + 200 × g; 200 × g + 400 × g; 200 × g + 800 × g; 400 × g + 400 × g; 400 × g + 800 × g. Samples of 3 ml of blood were drawn from each animal by means of cardiac puncture. The blood was stored in Vacutainer collection tubes containing 3.2% sodium citrate. The blood from the control group animals was analyzed without being subjected to centrifugation. After the blood from the other groups of animals had been subjected to centrifugation, the whole plasma was collected and subjected to platelet counting in the lower third of the sample.

RESULTS

We obtained greatest platelet enrichment in the subgroup with two centrifugations comprising 400 × g for 10 min + 400 × g for 10 min, in which the mean platelet concentration was 11.30 times higher than that of the control group.

CONCLUSION

It was possible to obtain a high platelet concentration using viable simple techniques, by means of centrifugation of whole blood and use of commonly used materials. The most effective method for obtaining platelet concentrate was found in samples subjected to two centrifugations.

Does Platelet-Rich Fibrin Enhance Bone Quality and Quantity of Alveolar Cleft Reconstruction?

BACKGROUND

Recently, platelet-rich fibrin (PRF) was described as a second-generation platelet concentrate. PRF is known as a rich source of autologous cytokines and growth factors and is universally used for tissue regeneration in clinical medicine.

OBJECTIVE

The aim of the current study was to evaluate the effect of PRF on the quality and quantity of bone formation in unilateral maxillary alveolar cleft reconstruction.

PATIENTS AND METHODS

Twenty-four patients with unilateral alveolar cleft underwent bone reconstruction. Patients were randomly divided into two groups. Group A consisted of patients grafted with PRF combined with autogenous anterior iliac crest bone graft. Group B patients were grafted using autogenous bone graft alone (control group). Computed tomography was performed 6 months postoperatively to assess the quality and quantity of the newly formed bone.

RESULTS

The percentage of newly formed bone (quantity) in group A ranged from 79.74% to 88.4%, with a mean percentage of 82.6% ± 3.9%. In group B, the percentage of bone formation ranged from 60.3% to 76.4%, with a mean percentage of 68.38% ± 6.67%. There was a statistically significant increase in the percentage of newly formed bone in group A. The mean bone density (quality) of the newly formed bone was lower in group A than group B, but the difference was not statistically significant (P < .05).

CONCLUSIONS

PRF in combination with autogenous bone was beneficial in improving the volume of newly formed bone in alveolar cleft reconstruction and does not enhance bone density.

Combination of Mineral Trioxide Aggregate and Platelet-rich Fibrin Promotes the Odontoblastic Differentiation and Mineralization of Human Dental Pulp Cells via BMP/Smad Signaling Pathway

INTRODUCTION

Recent reports have shown that the combined use of platelet-rich fibrin (PRF), an autologous fibrin matrix, and mineral trioxide aggregate (MTA) as root filling material is beneficial for the endodontic management of an open apex. However, the potential of the combination of MTA and PRF as an odontogenic inducer in human dental pulp cells (HDPCs) in vitro has not yet been studied. The purpose of this study was to evaluate the effect of the combination of MTA and PRF on odontoblastic maturation in HDPCs.

METHODS

HDPCs extracted from third molars were directly cultured with MTA and PRF extract (PRFe). Odontoblastic differentiation of HDPCs was evaluated by measuring the alkaline phosphatase (ALP) activity, and the expression of odontogenesis-related genes was detected using reverse-transcription polymerase chain reaction or Western blot. Mineralization formation was assessed by alizarin red staining.

RESULTS

HDPCs treated with MTA and PRFe significantly up-regulated the expression of dentin sialoprotein and dentin matrix protein-1 and enhanced ALP activity and mineralization compared with those with MTA or PRFe treatment alone. In addition, the combination of MTA and PRFe induced the activation of bone morphogenic proteins (BMP)/Smad, whereas LDN193189, the bone morphogenic protein inhibitor, attenuated dentin sialophosphoprotein and dentin matrix protein-1 expression, ALP activity, and mineralization enhanced by MTA and PRFe treatment.

CONCLUSIONS

This study shows that the combination of MTA and PRF has a synergistic effect on the stimulation of odontoblastic differentiation of HDPCs via the modulation of the BMP/Smad signaling pathway.

Distraction Osteogenesis Using Bone Matrix Osteotensors in Ectodermal Dysplasia: A Case Report

INTRODUCTION

Ectodermal dysplasia patients require complex oral rehabilitation. Bone matrix Osteotensors activate the patient's own stem cells to promote new bone formation through an autogenous growth factor cascade generated by a targeted flapless bone distraction before implant and/or bone graft therapy.

MATERIALS AND METHODS

The maxillary and mandibular bone were activated 21 (for type I bone) to 45 days (for type IV bone) before implant and/or bone substitute installation. Purpose-designed Osteotensors initiated massive recruitment of stem cells in the intended bone recipient site, thereby triggering neoangiogenesis and osteogenesis. After new bone formation, root-form implants and Diskimplants were installed. Functional loading was obtained at 48 hours using highly rigid, screw-secured fixed upper and lower full-arch prostheses.

RESULTS

At 3 years, all implants appeared clinically and radiologically osseointegrated with an excellent functional and esthetic outcome.

CONCLUSION

Flapless distraction osteogenesis using bone matrix Osteotensors several weeks before surgery improved the initial quality and volume of the recipient bone bed. This minimally invasive approach allows future successful immediate implant-supported complete maxillomandibular fixed rehabilitation without preliminary grafting procedures in patients with an unfavorable initial bone anatomy.

Influence of Leukocyte- and Platelet-Rich Fibrin (L-PRF) in the Healing of Simple Postextraction Sockets: A Split-Mouth Study

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.

Effects of platelet-rich fibrin and piezosurgery on impacted mandibular third molar surgery outcomes

Introduction

The aim of this study was the comparision of postoperative outcomes in impacted mandibular third molars that were treated using either platelet-rich fibrin (PRF), a combination of PRF and piezosurgery, or conventional rotatory osteotomy.

Patient and methods

The study included 20 patients; 40 extractions of impacted mandibular third molars were performed. Patients were divided into two main groups. In group A (n = 20), traditional surgery was performed on one side (Group 1, n = 10); traditional surgery was performed, and PRF was administered to the extracted socket on the other side of same patient (Group 2, n = 10). In group B (n = 20), on one side, piezosurgery was used for osteotomy, and PRF was administered (Group 3, n = 10); on the other side of same patient, traditional surgery was performed (Group 4, n = 10). Parameters assessed at baseline for each patient included pain, the number of analgesics taken, trismus, and cheek swelling. These variables were also assessed on postoperative days 1, 2, 3, and 7.

Results

Statistical analysis revealed a significant reduction in postoperative pain (sum of 1^st, 2^nd, 3^rd and 7^th days) and trismus (on postoperative day 1) in group 2 (traditional surgery + PRF group), and in postoperative pain, the number of analgesics taken (sum of 1^st, 2^nd,3^rd and 7^th days) and trismus (on postoperative day 1) in group 3 (piezosurgery + PRF group) compared to groups 1 and 4 (traditional surgery groups), (p ≤ 0.05). However, swelling on postoperative days 1, 3, and 7 did not differ among the groups (p > 0.05). Only difference was on second day between groups 1–4 and 2–4 (p ≤ 0.05).

Conclusions

The results of our study have shown that the use of PRF with traditional surgery and PRF combined with piezosurgery significantly reduced pain during the postoperative period. In addition, PRF in combination with piezosurgery significantly decreased the number of analgesics taken. Both operations also significantly decreased trismus 24 h after the surgery. As a result of this study, PRF and combination use of PRF and piezosurgery have positive effects in reducing postoperative outcomes after impacted third molar surgery.

The Adjunctive Effect of Platelet-Rich Fibrin to Connective Tissue Graft in the Treatment of Buccal Recession Defects: Results of a Randomized, Parallel-Group Controlled Trial

BACKGROUND

Platelet-rich fibrin (PRF) is an autologous preparation that has encouraging effects in healing and regeneration. The aim of this trial is to evaluate the effectiveness of coronally advanced flap (CAF) + connective tissue graft (CTG) + PRF in Miller Class I and II recession treatment compared to CAF + CTG.

METHODS

Forty patients were treated surgically with either CAF + CTG + PRF (test group) or CAF + CTG (control group). Clinical parameters of plaque index, gingival index, vertical recession (VR), probing depth, clinical attachment level (CAL), keratinized tissue width (KTW), horizontal recession (HR), mucogingival junction localization, and tissue thickness (TT) were recorded at baseline and 3 and 6 months after surgery. Root coverage (RC), complete RC (CRC), attachment gain (AG), and keratinized tissue change (KTC) were also calculated.

RESULTS

All individuals completed the entire study period. At baseline, mean VR, HR, CAL, KTW, and TT values were similar (P >0.05). In both groups, all parameters showed significant improvement after treatment (P <0.001), and except TT (P <0.05), no intergroup difference was observed at 6 months after surgery. The amount of RC and AG, but not KTC and CRC, was higher in the PRF-applied group (P <0.05).

CONCLUSIONS

According to the results, the addition of PRF did not further develop the outcomes of CAF + CTG treatment except increasing the TT. However, this single trial is not sufficient to advocate the true clinical effect of PRF on recession treatment with CAF + CTG, and additional trials are needed.