Bone regeneration in the maxillary sinus using an autologous fibrin-rich block with concentrated growth factors alone

Retrospective Study of Maxillary Sinus Augmentation Using Demineralized Tooth Block Bone for Dental Implant

(1) Background: When placing implants in the maxillary posterior region with insufficient alveolar bone, a maxillary sinus elevation is necessary. Autogenous bone, though biologically ideal, poses risks and discomfort due to donor site harvesting. Block-type autogenous tooth bone graft material, made from the patient's own extracted tooth, offers similar biological stability without these drawbacks. (2) Methods: This study observed the progress of 19 implant patients who were treated with maxillary sinus elevation procedures using block-type autogenous tooth bone graft material at the Daegu Catholic University Medical Center. Extracted teeth were processed into demineralized tooth block bone. After elevating the sinus membrane, implants and the tooth bone graft material were placed in the space, and the bony window was repositioned. Postoperative evaluations through clinical observation and radiographic imaging assessed sinus membrane elevation, alveolar bone height increase, and implant osseointegration. (3) Results: Results showed proportional increases in alveolar bone height to the graft material size, with long-term stability. No postoperative complications occurred, even with sinus membrane perforation, and implants remained stable. (4) Conclusions: The study concludes that maxillary sinus lifts using block-type autogenous tooth bone graft material provide excellent bone induction and biocompatibility, making this a highly beneficial method for both dentists and patients.

Effects of Platelet-Rich Plasma and Concentrated Growth Factor on Viability of Ultra-Diced Cartilage Grafts in a Rabbit Model

BACKGROUND

Although rhinoplastic surgery has progressed considerably in recent years, nasal dorsal irregularities still cause postoperative distress for both surgeons and patients.

PURPOSE

The aim of this study was to measure the association between two biologic graft adjuncts, platelet-rich plasma (PRP) and concentrated growth factor (CGF), and ultra-diced cartilage viability in an animal model.

STUDY DESIGN, SETTING, AND SAMPLE

This study was designed as a randomized in-vivo study using a rabbit model. Fourteen rabbits were utilized in this investigation. The ultra-diced cartilage was obtained from auricular cartilage.

PREDICTOR VARIABLE

The graft biologic adjunct is the predictor variable. There were three treatment groups: graft mixed with PRP or CGF or untreated (control). The grafts were placed in three separate pockets opened on the same rabbit. Grafts were harvested 3 months after insertion for analysis.

MAIN OUTCOME VARIABLE(S)

The primary outcome variable was histopathological and regenerative scores obtained from multiple histopathological parameters indicating the viability of the cartilage. Histopathological score parameters were chondrocyte loss, inflammation, fibrosis, cartilage fragmentation, and calcified area formations in the lacunae. Regenerative score parameters were peripheral cell proliferation in the cartilage tissue, vascularization in the connective tissue, proteoglycan increase in the matrix, and the amount of connective tissue.

COVARIATES

The variables were age, sex, and weight.

ANALYSES

Statistical analysis employed the analysis of variance test, with a significance level of P < .05.

RESULTS

The sample was composed of 14 rabbits and 42 samples. The histopathologic scores were 11.93 (±2.49), 8.78 (±2.19), and 6.85 (±1.46) for the control, PRP, and CGF groups, respectively. A statistically significant difference was found in the PRP (P < .0275) and CGF (P < .0001) groups compared to the control group. The regenerative scores were 6.21 (±0.97), 8.85 (±1.70), and 12.07 (±1.26) for the control, PRP and CGF groups, respectively. A statistically significant difference was found in the PRP (P < .0159) and CGF (P < .0001) groups compared to the control group.

CONCLUSION AND RELEVANCE

This is the first study investigating the ultra-diced cartilage graft in an experimental animal model. Histopathological examination has shown that mixing ultra-diced cartilage with CGF or PRP increases viability by reducing the histopathological score and increasing the regenerative score.

The effect of platelet-rich fibrin, platelet-rich plasma, and concentrated growth factor in the repair of full thickness rotator cuff tears

BACKGROUND

Rotator cuff lesions rank among the prevalent causes of shoulder pain. Combining surgical interventions with growth factors, scaffolds, and stem cell therapies can effectively decrease the likelihood of rotator cuff repair recurrence. Platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factor (CGF), isolated from blood and rich in growth factors, have a critical role in cell migration, cell proliferation, and angiogenesis during the tissue regeneration process. Investigations have further substantiated the beneficial impact of PRP and PRF on the biomechanical and histologic attributes of the tendon-bone interface. We aimed to investigate the effectiveness of CGF compared with PRF and PRP in the repair of rotator cuff lesions as a new treatment strategy.

METHODS

Incision was performed on both shoulder regions of 21 adult rabbits. After 8 weeks, both shoulders of the rabbits were repaired by suturing. PRF and CGF were administered to 2 separate groups along with the repair. Tissues were collected for biomechanical measurements and histologic evaluations.

RESULTS

Histologically, CGF, PRF, and PRP showed similar results to the healthy control group. The level of improvement was significant in the PRF and PRP groups. In the PRF group, the distribution of Ki67 (+), CD31 (+), and CD34 (+) cells was determined intensely in the tendon-bone junction regions. Apoptotic cells increased significantly in the repair group compared with the healthy group, whereas fewer apoptotic cells were found in the PRF-, PRP-, and CGF-applied groups. In the biomechanical results, no statistical difference was recorded among the groups.

CONCLUSION

The use of PRF, PRP, and CGF in rotator cuff repair shows promise in shortening the treatment period and preventing the recurrence of rotator cuff lesions.

Application of sticky bone combined with concentrated growth factor (CGF) for horizontal alveolar ridge augmentation of anterior teeth: a randomized controlled clinical study

OBJECTIVE

This study was designed to estimate the effect of sticky bone combined with concentrated growth factor (CGF) on anterior alveolar horizontal augmentation during implantation.

METHODS

Twenty-eight patients were randomly assigned to either the test group (Group 1, n = 14) or the control group (Group 2, n = 14). Patients in Group 1 and Group 2 underwent GBR using sticky bone combined with CGF and bone powders mixed with saline, respectively. On postoperative Day 7, the patients completed the visual analogue scale (VAS). Three-dimensional models of maxillary alveolar bone were reconstructed from CBCT data at different periods, and the bone volume conversion rate was calculated with the assistance of a measurement marker guide. Labial bone thickness before and after trauma closure and bone density at six months postoperatively were also measured.

RESULTS

The mean bone volume conversion rate for Group 1 (72.09 ± 12.18%) was greater than that for Group 2 (57.47 ± 9.62%, P = 0.002). The VAS score was lower for Group 1 than for Group 2 (P = 0.032). At six months postoperatively, greater bone density was found in patients in Group 1 than in those in Group 2, although the difference was not statistically significant (P > 0.05). The change in the thickness of the labial bone graft material in Group 1 was smaller than that in Group 2 (P = 0.025).

CONCLUSION

Sticky bone combined with CGF was able to achieve better bone augmentation than conventional GBR. With excellent mechanical properties and the capacity to release growth factors, sticky bone is an ideal material for bone grafting.

TRIAL REGISTRATION

The study was registered at the Chinese Clinical Trial Registry on 10/04/2022 (Identification number: ChiCTR2200058500).

Novel Applications of Concentrated Growth Factors in Facial Rejuvenation and Plastic Surgery

Concentrated growth factor (CGF), which is a third-generation platelet concentrate product, exhibits good potential for repair and regeneration of soft and hard tissues, and has gradually attracted attention in the field of cosmetic plastic surgery. The purpose of this review is to summarize the application and research of CGF in the field of facial rejuvenation and plastic surgery. A comprehensive review of the literature about the applications of CGF in facial rejuvenation and plastic surgery was conducted in PubMed, Ovid MEDLINE, and Web of Science. According to the inclusion and exclusion criteria, a total of 22 articles were included in this review. In recent years, CGF has been applied in many aspects in the field of facial rejuvenation and plastic surgery, including skin photoaging, repairment of soft-tissue defects, rhinoplasty, hair loss, autologous fat transplantation, and scars. In addition, no significant adverse reactions have been reported so far. CGF is rich in high-concentration growth factors, which has great potential and application prospects in facial rejuvenation and plastic surgery. However, the applications of CGF still have some problems, such as the mechanism, time of decomposition, and long-term efficacy and safety, which are needed to be resolved in future.

Bone Tissue Engineering (BTE) of the Craniofacial Skeleton, Part I: Evolution and Optimization of 3D-Printed Scaffolds for Repair of Defects

Bone tissue regeneration is a complex process that proceeds along the well-established wound healing pathway of hemostasis, inflammation, proliferation, and remodeling. Recently, tissue engineering efforts have focused on the application of biological and technological principles for the development of soft and hard tissue substitutes. Aim is directed towards boosting pathways of the healing process to restore form and function of tissue deficits. Continued development of synthetic scaffolds, cell therapies, and signaling biomolecules seeks to minimize the need for autografting. Despite being the current gold standard treatment, it is limited by donor sites' size and shape, as well as donor site morbidity. Since the advent of computer-aided design/computer-aided manufacturing (CAD/CAM) and additive manufacturing (AM) techniques (3D printing), bioengineering has expanded markedly while continuing to present innovative approaches to oral and craniofacial skeletal reconstruction. Prime examples include customizable, high-strength, load bearing, bioactive ceramic scaffolds. Porous macro- and micro-architecture along with the surface topography of 3D printed scaffolds favors osteoconduction and vascular in-growth, as well as the incorporation of stem and/or other osteoprogenitor cells and growth factors. This includes platelet concentrates (PCs), bone morphogenetic proteins (BMPs), and some pharmacological agents, such as dipyridamole (DIPY), an adenosine A 2A receptor indirect agonist that enhances osteogenic and osteoinductive capacity, thus improving bone formation. This two-part review commences by presenting current biological and engineering principles of bone regeneration utilized to produce 3D-printed ceramic scaffolds with the goal to create a viable alternative to autografts for craniofacial skeleton reconstruction. Part II comprehensively examines recent preclinical data to elucidate the potential clinical translation of such 3D-printed ceramic scaffolds.

Progress in Regenerative Medicine: Exploring Autologous Platelet Concentrates and Their Clinical Applications

The goal of regenerative medicine is to achieve tissue regeneration. In the past, commonly used techniques included autologous or allogeneic transplantation and stem cell therapy, which have limitations, such as a lack of donor sites in the case of autologous transplantation and the invasiveness of stem cell harvesting. In recent years, research has, therefore, focused on new and less invasive strategies to achieve tissue regeneration. A step forward in this direction has been made with the development of autologous platelet concentrates (APCs), which are derived from the patient's own blood. They can be classified into three generations: platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factors (CGFs). These APCs have different structural characteristics, depending on the distinctive preparation method, and contain platelets, leukocytes, and multiple growth factors, including those most involved in regenerative processes. The purpose of this review is to clarify the most used techniques in the field of regenerative medicine in recent years, comparing the different types of APCs and analyzing the preparation protocols, the composition of the growth factors, the level of characterization achieved, and their clinical applications to date.

The efficacy of concentrated growth factor and platelet-rich fibrin as scaffolds in regenerative endodontic treatment applied to immature permanent teeth: a retrospective study

BACKGROUND

The aim of this retrospective study was to compare the efficacy of concentrated growth factor (CGF) and platelet-rich fibrin (PRF) as scaffolds in regenerative endodontic therapy (RET).

METHODS

Necrotic immature permanent teeth treated with regenerative endodontic therapy during January 2018 to August 2022 were divided into the CGF and PRF groups according to the scaffold. The CGF and PRF groups included 7 and 6 teeth, respectively. The efficacy of regenerative endodontic therapy was analyzed based on the clinical and radiological outcomes at three different follow up periods: T1 (3-6 months), T2 (6-12 months) and T3 (12-24 months). Statistical analysis was performed using the independent T test, Mann-Whitney test and Fisher's exact test at a significance level of 0.05.

RESULTS

The success rate of each stage in both groups was 100%. Through quantitative comparison of radiographic outcomes, there was no statistically significant difference between the two groups in terms of root development and periapical lesion healing at each stage, except that the increase rate of radiographic root area in PRF group in the T3 stage was above one in CGF group with statistically significance.

CONCLUSIONS

Both CGF and PRF had a similar clinical performance regarding resolution of clinical signs and symptoms, periapical lesion healing, and continued root development as scaffolds in RET. Further prospective studies with large samples for longer follow-up periods are needed.

Maxillary Sinus Augmentation Using Autologous Platelet Concentrates (Platelet-Rich Plasma, Platelet-Rich Fibrin, and Concentrated Growth Factor) Combined with Bone Graft: A Systematic Review

BACKGROUND

The current review aims to provide an overview of the most recent research on the potentials of concentrated growth factors used in the maxillary sinus lift technique.

MATERIALS AND METHODS

"PRP", "PRF", "L-PRF", "CGF", "oral surgery", "sticky bone", "sinus lift" were the search terms utilized in the databases Scopus, Web of Science, and Pubmed, with the Boolean operator "AND" and "OR".

RESULTS

Of these 1534 studies, 22 publications were included for this review.

DISCUSSION

The autologous growth factors released from platelet concentrates can help to promote bone remodeling and cell proliferation, and the application of platelet concentrates appears to reduce the amount of autologous bone required during regenerative surgery. Many authors agree that growth factors considerably enhance early vascularization in bone grafts and have a significantly positive pro-angiogenic influence in vivo when combined with alloplastic and xenogeneic materials, reducing inflammation and postoperative pain and stimulating the regeneration of injured tissues and accelerating their healing.

CONCLUSIONS

Even if further studies are still needed, the use of autologous platelet concentrates can improve clinical results where a large elevation of the sinus is needed by improving bone height, thickness and vascularization of surgical sites, and post-operative healing.

Alveolar ridge preservation in post-extraction sockets using concentrated growth factors: a split-mouth, randomized, controlled clinical trial

Aim

The aim of this clinical trial was to assess the impact of autologous concentrated growth factor (CGF) as a socket-filling material and its ridge preservation properties following the lower third molar extraction.

Materials and methods

A total of 60 sides of 30 participants who had completely symmetrical bilateral impacted lower third molars were enrolled. The primary outcome variables of the study were bone height and width, bone density, and socket surface area in the coronal section. Cone beam computed tomography images were obtained immediately after surgery and three months after surgery as a temporal measure. Follow-up data were compared to the baseline using paired and unpaired t-tests.

Results

CGF sites had higher values in height and width when compared to control sites (Buccal wall 32.9 ± 3.5 vs 29.4 ± 4.3 mm, Lingual wall 25.4 ± 3.5 vs 23.1 ± 4 mm, and Alveolar bone width 21.07 ± 1.55vs19.53 ± 1.90 mm, respectively). Bone density showed significantly higher values in CGF sites than in control sites (Coronal half 200 ± 127.3 vs -84.1 ± 121.3 and Apical half 406.5 ± 103 vs 64.2 ± 158.6, respectively). There was a significant difference between both sites in the reduction of the periodontal pockets.

Conclusion

CGF application following surgical extraction provides an easy, low-cost, and efficient option for alveolar ridge preservation. Thus, the use of CGF by dentists during dental extractions may be encouraged, particularly when alveolar ridge preservation is required.

Clinical trial registration

TCTR identification, TCTR20221028003.

Histological examination of the effect of concentrated growth factor (CGF) on healing outcomes after maxillary sinus floor augmentation surgery

A double-blind clinical trial was conducted to examine the effect of concentrated growth factor (CGF), a new generation of platelet derivatives, on the healing outcome of maxillary sinus floor augmentation during maxillary sinus lift surgery. The study included 9 patients referred to the Tabriz University, Faculty of Dentistry, aged 30-80 years, with bilateral posterior partial edentulous or edentulous maxilla who underwent the procedure using a split-mouth technique. After lifting the Schneiderian membrane, bovine xenograft was randomly applied on one side (for example, left maxillary sinus) and CGF on the other side (for example, right maxillary sinus). Results from alizarin red and hematoxylin-eosin staining methods showed that the percentage of bone formed in the CGF group (112.41±26.34% and 96.16±24.49%, respectively) was significantly higher than in the control group (64.99±24.96% and 60.16±16.39%, respectively) (P<0.05). In addition, after 6 months, the amount of residual graft material in the control group (xenograft) was significantly higher than in the CGF group (P<0.05). These findings demonstrate that the use of CGF during open sinus lift surgery is reliable for the placement of dental implants.

Use of CGF in Oral and Implant Surgery: From Laboratory Evidence to Clinical Evaluation

Edentulism is the condition of having lost natural teeth, and has serious social, psychological, and emotional consequences. The need for implant services in edentulous patients has dramatically increased during the last decades. In this study, the effects of concentrated growth factor (CGF), an autologous blood-derived biomaterial, in improving the process of osseointegration of dental implants have been evaluated. Here, permeation of dental implants with CGF has been obtained by using a Round up device. These CGF-coated dental implants retained a complex internal structure capable of releasing growth factors (VEGF, TGF-β1, and BMP-2) and matrix metalloproteinases (MMP-2 and MMP-9) over time. The CGF-permeated implants induced the osteogenic differentiation of human bone marrow stem cells (hBMSC) as confirmed by matrix mineralization and the expression of osteogenic differentiation markers. Moreover, CGF provided dental implants with a biocompatible and biologically active surface that significantly improved adhesion of endothelial cells on CGF-coated implants compared to control implants (without CGF). Finally, data obtained from surgical interventions with CGF-permeated dental implants presented better results in terms of optimal osseointegration and reduced post-surgical complications. These data, taken together, highlight new and interesting perspectives in the use of CGF in the dental implantology field to improve osseointegration and promote the healing process.

Emerging roles of platelet concentrates and platelet-derived extracellular vesicles in regenerative periodontology and implant dentistry

Platelet concentrates (PCs) are easily obtained from autogenous whole blood after centrifugation and have evolved through three generations of development to include platelet-rich plasma, platelet-rich fibrin, and concentrated growth factor. Currently, PCs are widely used for sinus floor elevation, alveolar ridge preservation, periodontal bone defects, guided bone regeneration, and treatment of gingival recession. More recently, PCs have been leveraged for tissue regeneration to promote oral soft and hard tissue regeneration in implant dentistry and regenerative periodontology. PCs are ideal for this purpose because they have a high concentration of platelets, growth factors, and cytokines. Platelets have been shown to release extracellular vesicles (P-EVs), which are thought to be essential for PC-induced tissue regeneration. This study reviewed the clinical application of PCs and P-EVs for implant surgery and periodontal tissue regeneration.

The Bone Lid Technique in Oral and Maxillofacial Surgery: A Scoping Review

This scoping review aimed at reporting the outcomes of the bone lid technique in oral surgery in terms of bone healing, ridge preservation, and incidence of complications. Bone-cutting instruments and stabilization methods were also considered. PubMed, Scopus, and the Cochrane Register of Controlled Trials were searched using a combination of terms, including bone lid, bony window, piezosurgery, microsaw, cysts, endodontic surgery, impacted teeth, and maxillary sinus. A hand search was also performed. The last search was conducted on 30 November 2021. No date limitation was set. Searches were restricted to human clinical studies published in English. All types of study design were considered except reviews and case reports. After a two-step evaluation, 20 (2 randomized studies, 2 case-control studies, 3 cohort studies, 13 case series) out of 647 screened studies were included, reporting on 752 bone lid procedures. The bone lid technique was associated with favorable bone healing when compared to other methods, and with a very low incidence of major complications. Clinical indications, surgical procedures, study design, follow-up duration, and outcomes varied among the studies. Overall, favorable outcomes were reported using the bone lid approach, though evidence-based studies were scarce.

"Sticky Bone" Preparation Device: A Pilot Study on the Release of Cytokines and Growth Factors

Sticky bone, a growth factor-enriched bone graft matrix, is a promising autologous material for bone tissue regeneration. However, its production is strongly dependent on manual handling steps. In this sense, a new device was developed to simplify the confection of the sticky bone, named Sticky Bone Preparation Device (SBPD^®). The purpose of this pilot study was to investigate the suitability of the SBPD^® to prepare biomaterials for bone regeneration with autologous platelet concentrates. The SBPD^® allows the blending of particulate samples from synthetic, xenograft, or autogenous bone with autologous platelet concentrates, making it easy to use and avoiding the need of further manipulations for the combination of the materials. The protocol for the preparation of sticky bone samples using the SBPD^® is described, and the resulting product is compared with hand-mixed SB preparations regarding in vitro parameters such as cell content and the ability to release growth factors and cytokines relevant to tissue regeneration. The entrapped cell content was estimated, and the ability to release biological mediators was assessed after 7 days of incubation in culture medium. Both preparations increased the leukocyte and platelet concentrations compared to whole-blood samples (p < 0.05), without significant differences between SB and SBPD^®. SBPD^® samples released several growth factors, including VEGF, FGFb, and PDGF, at concentrations physiologically equivalent to those released by SB preparations. Therefore, the use of SBPD^® results in a similar product to the standard protocol, but with more straightforward and shorter preparation times and less manipulation. These preliminary results suggest this device as a suitable alternative for combining bone substitute materials with platelet concentrates for bone tissue regeneration.

Osteotome sinus floor elevation with concentrated growth factor and simultaneous implant placement with or without bone grafting: a retrospective study

The aim of this study was to compare the clinical effects of osteotome sinus floor elevation (OSFE) combined with concentrated growth factor (CGF) and simultaneous implant placement with or without bone grafting in the maxillary posterior region, where the residual bone height (RBH) was 4-6 mm. A total of 44 patients who underwent OSFE combined with CGF and the simultaneous placement of 60 implants (group A, 31 implants with bone grafting; group B, 29 implants without bone grafting) were included in this retrospective study. The clinical indicators of implants were observed for 24 months. Sinus floor lift height was 6.02 ± 0.99 mm in group A and 5.81 ± 0.72 mm in group B (P = 0.360) after surgery. There was no significant difference in the vertical bone resorption between the two groups at 24 months (P = 0.097). Postoperative pain at 14 days (visual analogue scale) was significantly greater in patients with bone grafting when compared to those without bone grafting (P < 0.001). There was no significant difference in marginal bone loss (MBL) between the two groups (P = 0.707 for MBL during the first 12 months, P = 0.922 for MBL during months 12-24). The implant success rate was 100% with or without bone grafting. The technique of OSFE with CGF, either with or without bone grafting, is safe and reliable in patients with RBH 4-6 mm.

Effect of advanced platelet-rich fibrin and concentrated growth factor on tissues around implants in maxillary anterior region

Aim

To assess the effect of advanced platelet-rich fibrin (APRF) and concentrated growth factor (CGF) on tissues around implants in the maxillary anterior region.

Settings and Design

This was a prospective clinical study.

Materials and Methods

Thirty subjects were divided into three groups with 10 dental implants in each group, i.e., Group 1: Control group, Group 2: Endosseous implant placement with APRF, and Group 3: Endosseous implant placement with CGF. The subjects were assessed at baseline (at the time of prosthesis placement), 2 weeks, 2 months, 6 months, and 1 year for modified sulcular bleeding index, periimplant probing depth, mucosal suppuration, bleeding on probing, crestal bone level as well as implant stability.

Statistical Analysis Used

Oneway Analysis of variance and Post hoc Bonferroni were the statistical tests used.

Results

The difference in implant stability at 2 months was significantly (P < 0.05) more among the control and CGF groups compared to APRF group. However; the crestal bone levels, periimplant probing depth, modified sulcular bleeding index, mucosal suppuration, and bleeding on probing were statistically non-significant (P > 0.05).

Conclusion

CGF and APRF accelerated osseointegration. Furthermore, they had a positive effect on stabilization values. However, CGF showed better results and with further clinical trials may show a positive effect on implant healing period.

Evaluation of the efficacy of concentrated growth factor along with bovine-derived xenograft and collagen membrane in the treatment of Degree II mandibular molar furcation defect – A clinicoradiographic study

Background:

The ultimate goal of furcation defect therapy is furcation closure via periodontal regeneration. However, the process of periodontal regeneration is affected by the regenerative environment of signaling molecules and growth factors due to which consistent findings of complete furcation closure could not be attained. In this study, we have evaluated the use of concentrated growth factor (CGF) which provides sustained release growth factors in conjunction with bovine-derived xenograft anorganic bovine bone (ABB) in guided tissue regeneration (GTR) of Degree II mandibular molar furcation defect.

Materials and Methods:

Twenty patients with Degree II mandibular molar furcation defects were selected for the study. Each group consisted of 10 patients and a total of 10 sites were treated in each group. The control sites were treated with GTR and ABB, while the experimental sites received CGF mixed with ABB along with GTR. Clinical parameters recorded were Plaque Index, Gingival Index, vertical probing depth, and horizontal probing depth measured at baseline and 6 months. Radiographic parameters such as the vertical height of defect, horizontal depth of defect, and percentage of vertical and horizontal bone fill were recorded at baseline and 6 months.

Results:

All the parameters recorded showed a significant reduction from baseline to 6 months in both the groups. Significantly higher vertical and horizontal bone fill was observed in the experimental group as compared to the control group.

Conclusion:

The use of CGF showed a positive additive efficacy in enhancing the events of periodontal regeneration in the treatment of Degree II mandibular molar furcation defect.

Randomized controlled study on effect of concentrated growth factors on crestal bone levels and peri-implant bone density in dental implants

Introduction:

Modern dentistry aims to restore the comfort and health of the stomatognathic system. Dental implants have emerged as a promising option for this purpose. Concentrated growth factors (CGFs) have been suggested to enhance the healing of bone grafts and enhance the integration of implants into the bone. Growth factors are proteins which regulate the complex process of wound healing. They play an important role in cell migration, cell proliferation, and angiogenesis in the tissue regeneration phase. CGF was first developed by Sacco in 2006. It can be used as a barrier membrane to accelerate soft-tissue healing. CGF does not require any chemical or anticoagulants, and hence, it is free from viral transmission diseases. Crestal bone levels, peri-implant bone density, bleeding, probing depth, mobility, occlusion factors, restoration adequacy, radiographic images, oral hygiene, and patient health status are some of the important parameters for determining longevity of success rates in implant dentistry. This study will assess the peri-implant bone density and crestal bone levels with and without the use of CGF.

Aim:

To evaluate the effect of CGFs on peri-implant bone density and in the preservation of crestal bone levels around dental implants.

Materials and Methods:

Sampling procedure: Random selection of population (Sealed envelope method)

Number of groups: Two-Control group (Group 1) and Experimental group (Group 2)

Sample size: 20

For Group 2, implants were placed with CGF. For Group 1, implants were placed without CGF. The peri-implant bone density and bone levels were measured by Digora and signora software.

Results:

The mean crestal bone loss on the mesial aspect of implants placed in Group 2 is 0.294 mm and Group 1 is 0.345 mm, and the mean crestal bone loss on the distal aspect of implants placed in Group 2 is 0.320 mm and in Group 1 is 0.331 mm. There are no many significant differences on mesial and distal aspects around implants between the two groups Intragroup comparison of bone density values in Group 1 shows the mean difference from baseline to 1 month is 0.6, and after three and 6 months periods are 1.1 and 1.1, respectively, which indicates not much significant improvement in bone density values in Group 1. Intergroup comparison shows a significant difference between both the groups starting from as early as the 1^st month.

Conclusion:

The results of this study indicate that CGF is significantly better in the regeneration of bone around the implants when comparing with nonCGF groups. Although CGF showed improvement in bone formation, there are no many differences in crestal bone level changes on mesial and distal sides of the implants between the two groups.

Application of concentrated growth factor to autotransplantation with inflammation in recipient area

OBJECTIVE

The purpose of this study was to apply concentrated growth factor (CGF) to the transplanted area with inflammation, to observe the clinical effects of CGF on the inflammation area assisted by 3D printing technology.

METHODS

A total of 52 compromised mandibular first or second molar with chronic periapical lesions were transplanted with mature third molars. The patients were divided into CGF group (n = 26) and control group (n = 26) and transplanted into fresh extraction sockets with or without CGF. All the patients underwent clinical and radiographic examinations during the follow-up.

RESULTS

Average surgery and extra-oral time were 39 min (± 7.8) and 42 s (± 10.2). The success rates of CGF group and control group were 100% and 92.3% respectively. Most of the periapical lesions in CGF group healed completely within 3 months, which was significantly faster than control group. The initial stability of CGF group was better than control group immediately after operation, and the degree of pain in CGF group was lower than control group on the 1st and 3rd day after operation.

CONCLUSIONS

The application of CGF in recipient site with chronic periapical lesions can accelerate the regeneration of alveolar bone and the healing of inflammation, greatly shorten the healing period. Meanwhile, CGF help to reduce postoperative pain and reaction at the early stage of healing and increase the success rate of autogenous tooth transplantation (ATT). Additionally, the use of 3D printing model can greatly reduce the extra-oral time of donor teeth.

Concentrated growth factor regulates the macrophage-mediated immune response

Concentrated growth factor (CGF) is a promising regenerative material that serves as a scaffold and adjunct growth factor for tissue engineering. The host immune response, particularly macrophage activity, plays a critical role in injury repair and tissue regeneration. However, the biological effect of CGF on the immune response is not clear. To enrich the theoretical groundwork for clinical application, the present study examined the immunoregulatory role of CGF in macrophage functional activities in vitro. The CGF scaffold appeared as a dense fibrin network with multiple embedded leukocytes and platelets, and it was biocompatible with macrophages. Concentrated bioactive factors in the CGF extract enhanced THP-1 monocyte recruitment and promoted the maturation of suspended monocytes into adherent macrophages. CGF extract also promoted THP-1 macrophage polarization toward the M2 phenotype with upregulated CD163 expression, as detected by cell morphology and surface marker expression. A cytokine antibody array showed that CGF extract exerted a regulatory effect on macrophage functional activities by reducing secretion of the inflammatory factor interleukin-1β while inducing expression of the chemokine regulated on activation, normal T cell expressed and secreted. Mechanistically, the AKT signaling pathway was activated, and an AKT inhibitor partially suppressed the immunomodulatory effect of CGF. Our findings reveal that CGF induces a favorable immune response mediated by macrophages, which represents a promising strategy for functional tissue regeneration.

Analysis of CGF Biomolecules, Structure and Cell Population: Characterization of the Stemness Features of CGF Cells and Osteogenic Potential

Concentrated Growth Factors (CGF) represent new autologous (blood-derived biomaterial), attracting growing interest in the field of regenerative medicine. In this study, the chemical, structural, and biological characterization of CGF was carried out. CGF molecular characterization was performed by GC/MS to quantify small metabolites and by ELISA to measure growth factors and matrix metalloproteinases (MMPs) release; structural CGF characterization was carried out by SEM analysis and immunohistochemistry; CGF has been cultured, and its primary cells were isolated for the identification of their surface markers by flow cytometry, Western blot, and real-time PCR; finally, the osteogenic differentiation of CGF primary cells was evaluated through matrix mineralization by alizarin red staining and through mRNA quantification of osteogenic differentiation markers by real-time PCR. We found that CGF has a complex inner structure capable of influencing the release of growth factors, metabolites, and cells. These cells, which could regulate the production and release of the CGF growth factors, show stem features and are able to differentiate into osteoblasts producing a mineralized matrix. These data, taken together, highlight interesting new perspectives for the use of CGF in regenerative medicine.

The extract of concentrated growth factor enhances osteogenic activity of osteoblast through PI3K/AKT pathway and promotes bone regeneration in vivo

BACKGROUND

Concentrated growth factor (CGF) is a third-generation platelet concentrate product; the major source of growth factors in CGF is its extract; however, there are few studies on the overall effects of the extract of CGF (CGF-e). The aim of this study was to investigate the effect and mechanism of CGF-e on MC3T3-E1 cells in vitro and to explore the effect of combination of CGF-e and bone collagen (Bio-Oss Collagen, Geistlich, Switzerland) for bone formation in cranial defect model of rats in vivo.

METHODS

The cell proliferation, ALP activity, mineral deposition, osteogenic-related gene, and protein expression were evaluated in vitro; the newly formed bone was evaluated by histological and immunohistochemical analysis through critical-sized cranial defect rat model in vivo.

RESULTS

The cell proliferation, ALP activity, mineral deposition, osteogenic-related gene, and protein expression of CGF-e group were significantly increased compared with the control group. In addition, there was significantly more newly formed bone in the CGF-e + bone collagen group, compared to the blank control group and bone collagen only group.

CONCLUSIONS

CGF-e activated the PI3K/AKT signaling pathway to enhance osteogenic differentiation and mineralization of MC3T3-E1 cells and promoted the bone formation of rat cranial defect model.

The impact of autologous concentrated growth factors on the alveolar ridge preservation after posterior tooth extraction: A prospective, randomized controlled clinical trial

BACKGROUND

Alveolar ridge preservation can effectively decrease alveolar ridge resorption following tooth extraction, but it can be limited by reducing new bone formation and residual bone graft material. Efforts to develop more efficacious approaches are thus an area of active research.

PURPOSE

To assess the impact of autologous concentrated growth factors (CGF) on alveolar ridge absorption and osteogenesis following posterior tooth extraction.

MATERIALS AND METHODS

Fifty patients were randomly assigned to have extraction sockets treated with CGF or no treatment. At 10 days, 1 month, and 3 months postextraction, soft tissue color and texture were examined and evaluated with healing score. Cone-beam computed tomography (CBCT) scans were performed before and 3 months after extraction, while radiographic analyses were used to assess vertical and horizontal bone changes. Bone samples were collected from the extraction sockets during implant placement, and micro-computed tomography (micro-CT) scans and histological analysis were performed to evaluate new bone formation. t-Test or Mann-Whitney U test was used to compare data and the level of statistical significance was set at 0.05 for all analyses.

RESULTS

Forty-six patients completed the trial. Sockets in the experimental group exhibited significantly better healing score on Day 10 postextraction relative to the control group, whereas comparable healing was observed in both groups at 1 and 3 months postextraction. Experimental group exhibited reduced vertical bone changes relative to the control (p < 0.05). Significant reductions were observed in ridge width changes at 1 and 2 mm apical to the crest (p < 0.05), although differences at 3 and 5 mm apical to the crest were not significant. Significant differences of bone mineral density (BMD) and microarchitecture of trabecular bone were observed via micro-CT analyses, and the experimental group had better results.

CONCLUSION

CGF application following posterior tooth extraction may reduce vertical and horizontal bone resorption and promote new bone formation.

Clinical and radiographic evaluation of demineralized freeze-dried bone allograft with concentrated growth factor versus concentrated growth factor alone in the treatment of intrabony defects

Background

Periodontal disease is one of the major causes of alveolar bone loss. There are various ways of regenerating the lost bone, i.e. guided tissue regeneration, bone grafts, and growth factors. In this purview, it becomes immensely important for a clinician to decide the best modality of treatment. In this study, we compared the effect of demineralized freeze-dried bone allograft (DFDBA) in combination with concentrated growth factors (CGF) verses CGF alone.

Methods

This double-blind, split-mouth study was conducted on ten patients with two comparable bilateral intrabony defects. Each pair of defects was randomly treated by DFDBA + CGF or CGF alone. Clinical parameters such as plaque index (PI), modified gingival index (MGI), pocket probing depth (PPD), and relative attachment level (RAL) were recorded at baseline, three months, and six months. In addition, radiograph with grids was also taken at baseline and six months. The paired t-test was used to compare the pre- and post-treatment values and the unpaired t-test was used to compare the test and control group.

Results

The PI score decreased significantly from baseline to six months. Similarly, the mean MGI score decreased significantly from baseline to six months. The intragroup comparison showed that there was a significant reduction in PPD in both the test and control group. However, the intergroup comparison showed that the reduced pocket depth was not significant. The intragroup radiographic comparison showed that there was the significant formation of bone in both the test and control group but inter-group showed that the formation of bone among both the group were non-significant.

Conclusion

Radiographic and clinical outcomes of this study concluded that post six months, both groups demonstrated significant improvement in clinical and radiographic parameters. However, the addition of DFDBA to CGFs did not give any additional benefits.

Angiogenic Properties of Concentrated Growth Factors (CGFs): The Role of Soluble Factors and Cellular Components

Blood-derived concentrated growth factors (CGFs) represent a novel autologous biomaterial with promising applications in regenerative medicine. Angiogenesis is a key factor in tissue regeneration, but the role played by CGFs in vessel formation is not clear. The purpose of this study was to characterize the angiogenic properties of CGFs by evaluating the effects of its soluble factors and cellular components on the neovascularization in an in vitro model of angiogenesis. CGF clots were cultured for 14 days in cell culture medium; after that, CGF-conditioned medium (CGF-CM) was collected, and soluble factors and cellular components were separated and characterized. CGF-soluble factors, such as growth factors (VEGF and TGF-β1) and matrix metalloproteinases (MMP-2 and -9), were assessed by ELISA. Angiogenic properties of CGF-soluble factors were analyzed by stimulating human cultured endothelial cells with increasing concentrations (1%, 5%, 10%, or 20%) of CGF-CM, and their effect on cell migration and tubule-like formation was assessed by wound healing and Matrigel assay, respectively. The expression of endothelial angiogenic mediators was determined using qRT-PCR and ELISA assays. CGF-derived cells were characterized by immunostaining, qRT-PCR and Matrigel assay. We found that CGF-CM, consisting of essential pro-angiogenic factors, such as VEGF, TGF-β1, MMP-9, and MMP-2, promoted endothelial cell migration; tubule structure formation; and endothelial expression of multiple angiogenic mediators, including growth factors, chemokines, and metalloproteinases. Moreover, we discovered that CGF-derived cells exhibited features such as endothelial progenitor cells, since they expressed the CD34 stem cell marker and endothelial markers and participated in the neo-angiogenic process. In conclusion, our results suggest that CGFs are able to promote endothelial angiogenesis through their soluble and cellular components and that CGFs can be used as a biomaterial for therapeutic vasculogenesis in the field of tissue regeneration.

Effect of Platelet-Derived Concentrated Growth Factor on Single-Layer, Multi-Layer, and Crushed Onlay Cartilage Grafts

BACKGROUND

The main concern with utilizing cartilage grafts to achieve structural integrity and volume restoration is the loss of volume over time and their unpredictable viability. Preservation of the volume of cartilage grafts is necessary to ensure their long-term success.

OBJECTIVES

The main aim of this study was to investigate the effect of concentrated growth factor (CGF) sheet on single-layer, multi-layer, and crushed block cartilage grafts.

METHODS

Cartilage grafts obtained from the ears of rabbits were prepared in 3 different forms: single-layer, triple-layer, and crushed. After measuring the weight and thickness of the cartilage grafts, the grafts in the experimental group were wrapped with the prepared autologous CGF. These cartilage grafts were placed in subcutaneous pouches created on the backs of the rabbits. After 4 months, the rabbits were killed. The weight and thickness of the cartilage grafts were measured and the cartilage viability and peripheral changes were examined microscopically.

RESULTS

The percentage changes in the weights and thicknesses of the single-layer, multi-layer, and crushed cartilage grafts wrapped with CGF were found to be statistically significantly lower than in the control group. When the cartilage viability and changes in peripheral tissue were evaluated, CGF-wrapped cartilage groups did not achieve statistically significantly better scores than the untreated control groups.

CONCLUSIONS

In cases planned to receive a block cartilage graft, especially if graft resorption is not desired or should be minimized, wrapping the graft with autologous CGF is a feasible option.

Use of PRP, PRF and CGF in Periodontal Regeneration and Facial Rejuvenation-A Narrative Review

Growth factors (GFs) play a vital role in cell proliferation, migration, differentiation and angiogenesis. Autologous platelet concentrates (APCs) which contain high levels of GFs make them especially suitable for periodontal regeneration and facial rejuvenation. The main generations of APCs presented are platelet-rich plasma (PRP), platelet-rich fibrin (PRF) and concentrated growth factor (CGF) techniques. The purpose of this review is to provide the clinician with an overview of APCs' evolution over the past decade in order to give reliable and useful information to be used in clinical work. This review summarizes the most interesting and novel articles published between 1997 and 2020. Electronic and manual searches were conducted in the following databases: Pubmed, Scopus, Cochrane Library and Embase. The following keywords were used: growth factors, VEGF, TGF-b1, PRP, PRF, CGF and periodontal regeneration and/or facial rejuvenation. A total of 73 articles were finally included. The review then addresses the uses of the three different techniques in the two disciplines, as well as the advantages and limitations of each technique. Overall, PRP is mainly used in cases of hard and soft tissue procedures, while PRF is used in gingival recession and the treatment of furcation and intrabony defects; CGF is mainly used in bone regeneration.

Clinical evaluation of the treatment of multiple gingival recessions with connective tissue graft or concentrated growth factor using tunnel technique: a randomized controlled clinical trial

OBJECTIVE

To assess the effectiveness of the combination of tunnel technique (TT) and concentrated growth factor (CGF) for root coverage in treating multiple gingival recessions (GR) and compare with the connective tissue graft (CTG).

MATERIALS AND METHODS

Forty patients with Miller Class I and II maxillary or mandibular GR were randomly divided into two groups as follows: TT + CTG and TT + CGF. The results at baseline and 6 months were evaluated for the following clinical parameters: complete root coverage (CRC), mean root coverage (MRC), gingival thickness (GT), gingival recession width (RW), gingival recession depth (RD), and keratinized tissue width (KTW).

RESULTS

At 6 months, a statistically significant difference was found in RD, RW, MRC, CRC, KTW, and GT compared with the baseline (p < 0.05). MRC was determined 89.52±16.36% in the TT + CTG and 76.60±24.10% in the TT + CGF (p < 0.05). CRC was achieved in 66.7% of the TT + CTG and 47.4% of the TT + CGF (p < 0.05). The increase in KTW and GT was significantly better in the TT + CTG group compared to the TT + CGF (p < 0.05).

CONCLUSIONS

The study showed that TT + CGF did not improve the results as much as TT + CTG in the treatment of Miller Class I and II GR. However, this finding is not sufficient to advocate the true clinical effects of CGF on GR treatment with TT.

CLINICAL RELEVANCE

CGF could not serve as a direct alternative biomaterial to the gold standard CTG.

TRIAL REGISTRATION

ClinicalTrials.gov Identification Number: NCT04561947.

[Effect of concentrated growth factor combined with mineralized collagen material on the adhesion, proliferation, and osteogenic differentiation of bone marrow mesenchymal stem cells and the osteogenic effect in vivo]

Objective

To explore the effects of concentrated growth factor (CGF) combined with mineralized collagen (MC) materials on the adhesion, proliferation, and differentiation of bone marrow mesenchymal stem cells (BMSCs) and their osteogenic effects in vivo, and to provide a theoretical basis for the combined application of CGF and MC materials in bone defect regeneration and repair.

Methods

CGF was prepared from venous blood of healthy volunteers, and then CGF extracts (CGFe) were prepared. In vitro experiment: human BMSCs (hBMSCs) were divided into 4 groups. Groups A, B, and C were cultured with α-MEM medium [containing 10% fetal bovine serum (FBS) and 1% double antibody] containing 2%, 5%, and 10%CGFe, respectively; group D was cultured with α-MEM medium (containing 10%FBS and 1% double antibody) without CGFe. Scanning electron microscopy was used to observe the effect of CGFe on cell adhesion. Cell counting kit 8 (CCK-8) was used to detect the effect of CGFe on cell proliferation. After osteogenic induction, alkaline phosphatase (ALP) activity was detected and Western blot was performed to detect osteopontin (OPN) expression. In vivo experiment: Eighteen New Zealand big-eared rabbits were used to prepare circular bone defect models on the left and right mandibles, and implant CGF gel (prepared from autologous venous blood)+MC material (volume ratio 1∶1, experimental group) and simple MC material (control group), respectively. At 4, 8, and 12 weeks after operation, 6 rabbits were sacrificed respectively to obtain materials, and Micro-CT scanning was performed to observe the formation of new bone and material degradation in vivo.

Results

In vitro experiments: Scanning electron microscopy showed that the cells of groups A, B, and C spread better on MC materials than group D, with more pseudopodia. CCK-8 method showed that different concentrations of CGFe could promote cell proliferation, and the absorbance ( A) value of cells cultured for 2, 3, 5, and 7 days was in the order of group C>group B>group A>group D, the differences were significant ( P<0.05). ALP activity test showed that its activity was proportional to the osteogenic induction time and CGFe concentration ( P<0.05). Western blot analysis of osteogenic induction culture for 14 days showed that the relative expression of OPN protein in groups A, B, and C was significantly higher than that in group D, and the higher the CGFe concentration, the higher the relative expression of OPN protein ( P<0.05). In vivo experiment: Micro-CT observation showed that the new bone formation and material degradation of the experimental group were better than those of the control group at 4, 8, and 12 weeks after operation. Quantitative detection showed that the volume of new bone volume, new bone volume fraction, trabeculae number, and trabecular thickness of the experimental group were significantly higher than those of the control group at each time point, the residual material volume, residual material volume fraction, and trabecular separation were significantly lower than those of the control group, all showing significant differences ( P<0.05).

Conclusion

CGF can effectively promote the adhesion, proliferation, and osteogenic differentiation of BMSCs on MC materials, and 10%CGFe has the most significant effect. The combined application of CGF and MC material can significantly promote bone formation in vivo.

The effect of concentrated growth factor (CGF) in the surgical treatment of medication-related osteonecrosis of the jaw (MRONJ) in osteoporosis patients: a randomized controlled study

OBJECTIVES

The purpose of this present study was to evaluate the efficiency of the growth factors delivered by concentrated growth factor (CGF) on the healing process of osteoporotic patients with medication-related osteonecrosis of the jaws (MRONJ).

METHODS

This randomized controlled study was composed of osteoporotic female patients who were treated with oral bisphosphonates (BPs) and diagnosed with MRONJ. For the CGF group, each patient was treated with a local application of CGF at the surgical site after removing the necrotic bone, while the surgical area was primarily closed as traditional surgical therapy for the control group. The patients underwent clinical examinations for 6 months postoperatively to check the presence of infection and dehiscence.

RESULTS

Complete healing was achieved in 19 patients of 28 patients (mean age: CGF group, 73.57 ± 5.1; control group, 73.64 ± 5.49) diagnosed with MRONJ. There was no significant difference in post-op healing data between groups during healing periods (p > 0.05). In the CGF group (n = 14) in three cases, bone exposure without infection was detected, and one of them showed a recurrent infection. In the control group (n = 14) in six cases, bone exposure without infection was detected, and three of them also showed recurrent infection.

CONCLUSION

Although our results were not statistically significant, our findings suggest that the local application of CGF appears to be an effective approach to the surgical treatment of MRONJ in osteoporosis patients by improving tissue regeneration.

CLINICAL RELEVANCE

A specific treatment protocol to manage MRONJ is still controversial. This study justifies that CGF can be used in combination with surgical treatment.

Concentrated Growth Factors vs. Leukocyte-and-Platelet-Rich Fibrin for Enhancing Postextraction Socket Healing. A Longitudinal Comparative Study

Platelet concentrates (PCs) have been used for over 20 years in dentistry, as an adjunct to oral surgery procedures, to improve hard and soft tissue healing and control postoperative symptoms. Among various PCs, Leukocyte and Platelet-Rich Fibrin (L-PRF) has become very popular due to its excellent cost-effectiveness ratio, and to the simple preparation protocol, but comparative clinical studies with other PCs are lacking. The aim of this split-mouth cohort study was to evaluate the effect of Concentrated Growth Factors (CGF), a recently introduced PC, as compared to L-PRF for enhancing post-extraction socket healing. Methods: Patients in need of bilateral tooth extractions were included. Each side was treated with either CGF or L-PRF. Pain, socket closure and healing index were the main outcomes. Results: Forty-five patients (24 women), aged 60.52 ± 11.75 years (range 37–87 years) were treated. No significant difference in outcomes was found, except for Pain at day 1 (p < 0.001) and socket closure in the vestibulo-palatal/lingual dimension at day 7 post-extraction (p = 0.04), both in favor of CGF. Conclusions: based on the present results, CGF proved to be as effective and safe as L-PRF, representing a valid alternative option for improving alveolar socket healing and reducing postoperative discomfort.

Considerations for Clinical Use of Concentrated Growth Factor in Maxillofacial Regenerative Medicine

Different strategies have been utilized to facilitate mineralized/soft tissues. Concentrated growth factor (CGF) emerges as a promising biomaterial for regenerative therapy due to high levels of platelets, growth factors, and nucleated cells entrapped in the fibrin scaffold. This review aimed to collect extensive studies on CGF used in maxillofacial regenerative medicine, discussing current obstacles, and expressing some considerations of CGF use. Articles were retrieved systematically without time limitation. In total, 27 human studies were included and separated accordingly. In general, CGF has been most evaluated in implant related therapy and maxillofacial bone regeneration where a majority of articles have revealed favorable outcomes. Little studies have supported the effects on improving probing periodontal depth reductions and clinical attachment level gains for intrabony and furcation defect regeneration. Very little data with high-level evidence was available directly to investigate its effects on the soft tissue regeneration and postoperative complications reduction. The evidence supporting the clinical efficacy of CGF in maxillofacial regenerative medicine is limited. Some conflicting results are worrisome. In addition, the characterization of CGF preparation protocols and CGF's components was not performed in most studies. Further studies should make a consensus on standardized end-product of CGF including characterization of protocols and optimal ratio of CGF' components. Defined algorithms and evidence-based protocols for the clinical use of CGF should be also available.

Efficacy of concentrated growth factors combined with mineralized collagen on quality of life and bone reconstruction of guided bone regeneration

To evaluate the clinical efficacy of concentrated growth factors (CGFs) combined with mineralized collagen (MC) in guided bone regeneration (GBR). A retrospective study involving 29 patients treated with GBR technique, which was performed either CGF and MC complexes or MC alone. Implants were inserted simultaneously and cone-beam computed tomography was taken immediately, at 3 and 6 months postoperation. Questionnaires were completed by all patients so as to evaluate the main symptoms and daily activities during the first week after surgery. The outcomes of the two groups were statistically compared. All implants healed uneventfully. Patients in both groups suffered from different levels of discomfort for the reason of swelling, pain and chewing impairment on 1–2 days. Meanwhile, swelling of the Trial group was weaker than the Control group. When compared with the Control group, pain levels in Trial group were more rapidly reduced and patients took fewer analgesics from Day 3. Furthermore, the reconstitution mean value of the graft was thicker at 3 and 6 months in Trial group. CGFs complex with MC were beneficial to relieve the clinical symptoms, promote the peri-implant bone regeneration and shorten the healing time.

Effect of concentrated growth factors on frequency of alveolar Osteitis following partially-erupted mandibular third molar surgery: a randomized controlled clinical study

Background

The aim of this prospective study was to assess the effectiveness of concentrated growth factors (CGF) in preventing the development of alveolar osteitis (AO) after the extraction of partially-erupted mandibular third molars.

Methods

Seventy patients (26 men and 44 women) 18 years or older (mean age 25.86; range 18–35) underwent 140 third molar extractions. All the patients presented with bilateral, partially-erupted mandibular third molars and underwent surgical extractions. In each case, one socket received CGF and the other served as a control. The predictor variable was the CGF application and the sides were categorized as ‘CGF’ and ‘non-CGF’. The outcome variable was the development of AO during the first postoperative week. Other study variables included age and gender. Data were analyzed using Cochran’s Q test with the significance level set at a P value less than 0.05.

Results

The overall frequency of AO was 11.4% for the control group. The frequency of AO in the CGF group was significantly lower than in the non-CGF group (p < 0.001).

Conclusions

Based on the results of this study, application of CGF fibrin gel may decrease the risk of AO development after mandibular third molar surgery.

Trial registration

This study was registered in ClinicalTrials.gov database on November 1, 2019 (ID: NCT04151147, retrospectively registered).

Does Concentrated Growth Factor Used With Allografts in Maxillary Sinus Lifting Have Adjunctive Benefits?

PURPOSE

Recent studies have shown that the use of platelet concentration products alone, or in combination with variable graft materials, accelerates the new bone formation associated with sinus augmentation. The aim of this study was to measure the adjunctive effects of concentrated growth factor (CGF) used with allograft on new bone formation and augmentation stability in sinus lifting.

MATERIALS AND METHODS

This randomized controlled study included patients who presented for dental implant placement in atrophic posterior maxilla at the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, and who needed maxillary sinus augmentation. All patients were treated with a 2-stage surgical technique using sinus lifting bilaterally and implant placement 6 months later. During sinus lifting surgery, one side was grafted with allograft (group 1) and the other side with allograft mixed CGF (group 2). Cone-beam computed tomography was carried out immediately postoperatively and also 6 months after the augmentation to evaluate vertical bone height and percentage of resorption. Bone specimens were obtained at the time of implant placement and evaluated histomorphometrically to analyze the percentage of new bone formation and residual graft particle. Statistical comparisons were conducted between groups for all these measurements.

RESULTS

A total of 10 patients (2 females and 8 males) with a mean age of 57 years (range, 39 to 72) were enrolled in the study. Cone-beam computed tomography analysis revealed a significantly higher percentage of bone height resorption at the sixth month in group 1 (median, 9.32%) compared with group 2 (median, 6.37%) (P < .05). According to the histomorphometric examination, the percentage of new bone formation in group 2 (median, 36.41%) was higher than group 1 (median, 35.49%), but this difference did not reach statistical significance.

CONCLUSIONS

Using CGF with allografts supports the stabilization of gained vertical bone height after sinus augmentation, but further research is needed to determine the accelerating effects of CGF on new bone formation.

Dynamics and risk indicators of intrasinus elevation height following transalveolar sinus floor elevation with immediate implant placement: a longitudinal cohort study

Successful intrasinus graft consolidation is essential for the treatment outcome of transalveolar sinus floor elevation (SFE). This study was performed to examine the dynamics and risk indicators related to the elevation height after transalveolar SFE with grafting material and simultaneous implant placement. Fifty-two patients with 55 sites undergoing transalveolar SFE with immediate implant placement were enrolled retrospectively. Cone beam computed tomography (CBCT) images were collected and saved in DICOM format, at the following time-points: pre-surgery (T0), immediately post-surgery (T1), and 6 months post-surgery (T2). Voxel-based CBCT superimposition was performed to measure the sinus width, residual alveolar height, implant protrusion length, total elevation height, and apical graft height. The change in total elevation height from T1 to T2 was defined as the study outcome. Clinical and linear variables were analysed using linear regression. From T1 to T2, the total elevation height showed an average reduction of 1.0±1.1mm, while 10.9% sites showed an increased elevation height. Univariate regression analysis showed no significant correlation between tested clinical or linear variables and the study outcome. The results suggest that the change in elevation height was not influenced by the alveolar or sinus dimensions, graft materials, implant diameter, implant protrusion length, or the total elevation height at T1.

Tensile strength, growth factor content and proliferation activities for two platelet concentrates of platelet-rich fibrin and concentrated growth factor

Background/purpose

Platelet-rich fibrin (PRF) can be obtained by centrifuging fresh blood in the absence of anticoagulants. Varying the centrifugation speeds may produce tougher and richer concentrated growth factors (CGF). This study examines tensile strength, growth factor content, and the potential of CGF and PRF in promoting periodontal cell proliferation.

Materials and methods

Blood (40 mL/subject) was collected from 44 healthy subjects. PRF and CGF were prepared by centrifuging at 3000 rpm and switching speeds ranging within 3000 rpm, respectively. Fibrin strip was prepared and its tensile strength was measured. Transforming growth factor beta 1 (TGF-β1), platelet-derived growth factor BB (PDGF-BB), and epidermal growth factor (EGF) in the residual serum and fibrin clots were determined by enzyme-linked immunosorbent assay, and their effects on the proliferation of hFOB1.19 osteoblasts and human gingival fibroblasts were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay.

Results

Compared with PRF, tensile strength of CGF was significantly higher. Concentrations and amounts of PDGF-BB and EGF in CGF were significantly higher than those in PRF. Osteoblast number was significantly higher in the cultures with fetal bovine serum (FBS, 10%) and with PRF or CGF fibrin clots (5%, 10%, and 50%) compared to that without FBS. Moreover, osteoblast number in CGF, regardless of the preparation of 10% and 50%, was significantly greater than that in PRF. Similar findings were also observed for gingival fibroblasts among the various subjects.

Conclusion

Varying centrifugation speeds can modify the tensile strength and biological activities of platelet fibrin clots.

The Effect of Concentrated Growth Factor on Calvarial Bone in Diabetic Healing

The aim of this study was to evaluate the effect of Concentrated Growth Factor (CGF) on bone healing in diabetic rat model. Experimental diabetes was induced in 24 male Sprague-Dawley rats by streptozotocin. Twenty-four animals served as healthy controls. The animals were divided into 4 subgroups; empty bone defect, grafting with xenogenous graft (Geno-os, OsteoBiol, Turin-Italy), CGF administration, and combined application of the CGF with the xenogenous graft in critical-sized defects in the calvaria of the rats. The diabetic group was given 4 units of Neutral Protamin Hagedorn per day. After 6 weeks, all animals were sacrificed and bone healing was histologically and histomorphometrically analyzed, and the evaluation revealed that the new bone formation in diabetic animals was significantly lower than in healthy group (P: 0.001, P: 0.023). In both groups, the highest rate of ossification was observed in the combined use of xenogenous graft and CGF. When the new bone formation was examined in the graft and CGF group, no significant difference was found between control and diabetic group (P = 0.562; P > 0.05). In conclusion, in patients with diabetes mellitus, combination therapy of CGF with graft is expected to contribute positively to the healing of bone defect.

In vitro and in vivo effects of concentrated growth factor on cells and tissues

This article reviews the biological outcome of the concentrated growth factor (CGF), a new platelet derivative used for tissue regeneration, in published articles related to the use of this product in basic and clinical studies. An electronic literature research using PubMed and SCOPUS was performed using combination of keywords: "concentrated growth factor" (OR "CGF"), AND "stem cells," AND "cells" OR "cell proliferation" OR "cell migration" OR "cell differentiation," AND "repair" OR "survival" OR "revitalization," AND "tissue" OR "bone." Forty-five articles that were published between 2012 and 2020 met the inclusion criteria. These studies have used CGF as fresh solid form, freeze-dried, membrane, extract, or exudate. Most studies demonstrate the positive effects of CGF in a dose-dependent manner under certain concentrations. Studies comparing CGF with other platelet concentrates, report lower efficiency, no statistically significant differences, or better results for CGF. Combination of CGF with stem cells and biomaterials significantly improves bone regeneration and the effect of allograft or collagen membrane is better than CGF alone. For a better examination of the biological outcomes of CGF, the standardization of CGF preparation regarding the choice of the test tube material for blood collection, the required volume of blood, the necessary count of platelets in CGF, and the most appropriate type of CGF are recommended.

The Effects of Leukocyte-Platelet Rich Fibrin (L-PRF) on Suppression of the Expressions of the Pro-Inflammatory Cytokines, and Proliferation of Schwann Cell, and Neurotrophic Factors

This study evaluates the use of L-PRF as an autologous scaffold in nerve regeneration, and Schwann cells (SCs) proliferation and secretion of neurotrophic factors and its anti-inflammatory effect on SC Porphyromonas Gingivalis-Lipopolysaccharide (PG-LPS)-induced inflammatory responses in vitro. SEM was done to investigate various features of L-PRF. L-PRF-extracts was used to investigate the release of growth factors and treatment of SCs line. ELISA was applied to examine the release of IGF-1. The proliferative effect of L-PRF on SCs was assessed with CCK-8 assay. The effect of L-PRF on the mRNA and protein expression of SC neurotrophic factors were analyzed by RT-qPCR and ELISA. CCK-8 assay and RT-qPCR were used to determine the required concentration and the action time of PG-LPS before the anti-inflammatory effect of L-PRF was determined by measuring the changes in IL-1β, IL-6, and TNF-a with RT-qPCR and ELISA. There are different features in L-PRF. Fourteen days was sufficient to release adequate GF. The mRNA expressions of the pro-inflammatory cytokines were notably raised by PG-LPS in 3-hours treatment. L-PRF can increase SC proliferation, neurotrophic factors secretion, and suppress SC PG-LPS-induced inflammatory responses in vitro. L-PRF has the potential as an autologous biological additive for peripheral nerve regeneration in the event of nerve inflammation and injuries.

The use of concentrated growth factor in dental implantology: A systematic review

In the era of evidence based dentistry, a well-documented consolidated data about improvements in dentistry is a necessity. Concentrated growth factor (CGF) is an emerging trend in periodontology and now in implant dentistry. Various studies have been published in the literature evaluating the effect of CGF on implant osseointegration, implant stability, survival rate, sinus augmentation, and peri-implant defects. However, no systematic review has yet been documented. The present systematic review, being first of its kind, aimed to evaluate the potential outcomes of employing CGF in implant treatment. A literature search was carried out in PubMed and Google scholar for articles published between 2001 and 2019, with various keywords such as "CGF," "dental implant," "bone regeneration," "CGF," and "osseointegration." The screening of studies was done according to PRISMA guidelines. A total of eleven studies were included in this review. Majority of the included studies pointed toward the beneficial effects of CGF in implant treatment. CGF was seen to promote osseointegration and enhance bone regeneration. Although more clinical studies are required to validate the potential merits of CGF in the long run, the preliminary results seem promising.

Concentrate Growth Factors Regulate Osteogenic Dysfunction of MC3T3-E1 Cells Induced by High Glucose Through PI3K/Akt Signaling Pathway

INTRODUCTION

The aim of this study is to investigate the effects of Concentrate Growth Factors Extract (CGF-e) on the proliferation and osteogenic differentiation of MC3T3-E1 cells under high glucose condition.

MATERIALS AND METHODS

MC3T3-E1 cells were divided into 4 groups including normal glucose (5.5-mM) group (control), high glucose (25.5-mM) group, normal glucose + CGF-e group, and high glucose + CGF-e group. The proliferation, osteogenic differentiation and mineralization of osteoblasts were evaluated, respectively, by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, cytoskeleton analysis, alkaline phosphatase activity assay, alizarin red staining, and real-time polymerase chain reaction. Western blots analysis was used to explore the role of PI3K/Akt pathway.

RESULTS

The viability, osteogenic differentiation, and mineralization of MC3T3-E1 cells were significantly decreased by high glucose. All observed osteogenic dysfunction were inhibited by CGF-e. Moreover, the PI3K/Akt pathway was activated by CGF-e.

CONCLUSIONS

It was concluded that the soluble factors released by CGF could significantly attenuate high glucose-mediated MC3T3-E1 cells osteogenic dysfunction through the PI3K/Akt pathway.

One-Year Results Evaluating the Effects of Concentrated Growth Factors on the Healing of Intrabony Defects Treated with or without Bone Substitute in Chronic Periodontitis

Background

The restoration of damaged periodontium, especially one-wall intrabony defects, is a major challenge for clinicians. Concentrated growth factors (CGF) are a 100% autologous fibrin with multiple concentrated growth factors. The rigid fibrin structure of CGF makes it possible to preserve or reconstruct the initial bone volume. The aim of this study was to evaluate the clinical healing patterns after surgical application of CGF with and without a Bio-Oss graft in one-wall infrabony defects.

Material/Methods

We randomly divided 120 one-wall intrabony defects in 54 patients into 4 groups: flap surgery alone (Group 1), flap surgery with autologous CGF (Group 2), flap surgery with Bio-Oss (Group 3), and flap surgery with CGF+Bio-Oss (Group 4). Clinical parameters such as probing depth (PD) and clinical attachment level (CAL) change were recorded at baseline and at 6 and 12 months postoperatively.

Results

At 12 months postoperatively, Group 2 showed significant improvement in clinical parameters over Group 1 (P<0.05) and the results were significantly greater in Groups 3 and 4 compared to the other groups (P<0.05). Although no significant difference was noted between Groups 3 and 4 in clinical parameters (P>0.05) compared to Group 3, the mean change of CAL at 6–12 months in Group 4 was not significant (P>0.05).

Conclusions

CGF reduced periodontal intrabony defects depth and, when mixed with Bio-Oss, CGF showed better results in the early period and the effect was more stable.

A comparative study of the effects of concentrated growth factors in two different forms on osteogenesis in vitro

Extending the release cycle of growth factors to match the cycle of bone remodeling is difficult. When using concentrated growth factors (CGFs), the release of growth factors is excessively rapid. In the present study, CGF samples were prepared by centrifugation. CGF samples were then lyophilized and grinded into a powder, which was termed freeze‑dried CGF. The freeze‑dried CGF samples were mixed with chitosan‑alginate composite hydrogels, and the mixture was lyophilized. The result was a chitosan‑alginate composite CGF membrane, which was called sustained‑release CGF. This study investigated whether freeze‑dried CGF in a chitosan‑alginate composite gel can release CGF steadily to achieve effective osteogenesis. The proliferation and osteogenic expression of MC3T3‑E1 cells induced by the supernatants from incubation with freeze‑dried CGF and sustained‑release CGF were evaluated. The concentrations of the growth factors, transforming growth factor β1 (TGF‑β1), insulin‑like growth factor‑1 (IGF‑1), platelet‑derived growth factor‑AB (PDGF‑AB) and vascular endothelial growth factor (VEGF), in these two experimental groups at different times were determined by ELISA kits. The freeze‑dried CGF showed better osteogenic performance than the sustained‑release CGF in the early stages. At later stages, the sustained‑release CGF had significant advantages over freeze‑dried CGF in terms of promoting osteogenic mineralization. By characterizing the biologic properties of the CGF in the two different forms in vitro, we obtained a better understanding of their clinical effects.

Concentrated growth factor promotes proliferation, osteogenic differentiation, and angiogenic potential of rabbit periosteum-derived cells in vitro

OBJECTIVE

The aim of this research is to investigate the effects of concentrated growth factor (CGF) on the proliferation, osteogenic differentiation, and angiogenic potential of rabbit periosteum-derived cells (PDCs) in vitro.

METHODS

PDCs were isolated from the femoral and tibial periosteum of rabbits and cultured with or without CGF membranes or CGF conditioned media. Scanning electron microscopy (SEM) was used for the structural characterization. Cell Counting Kit-8 assay was used to measure cell proliferation. Alkaline phosphatase (ALP) activity of PDCs was also measured. Immunohistochemistry was used to detect the expression of CD34. Enzyme-linked immunosorbent assay (ELISA), quantitative real-time PCR (qPCR), and Western blot were used to evaluate the secretion and expression levels of osteogenic differentiation markers (bone morphogenetic protein-2, type I collagen, osteocalcin) and angiogenesis markers (vascular endothelial growth factor, basic fibroblast growth factor) in supernatants and PDCs at days 3, 7, 14, and 21.

RESULTS

The SEM analysis showed a dense three-dimensional fibrin network in CGF, and CGF membranes were covered by PDCs with elongated or polygonal morphological features. Compared with the control group, CGF significantly promoted the proliferation of PDCs during the experimental period (p < 0.05). Immunohistochemistry revealed that PDCs were dispersedly distributed among the CGF substrates, and CD34-positive cells were also present. Moreover, CGF significantly increased the ALP activity and upregulated the expression and secretion of osteogenic differentiation and angiogenesis markers in PDCs at days 3, 7, 14, and 21 (p < 0.05).

CONCLUSION

CGF can increase the proliferation and promote the osteogenic differentiation and angiogenic potential of PDCs in vitro. These results indicate that CGF can be used as a new therapeutic means for biotechnological and clinical applications.

The potential application of concentrated growth factor in pulp regeneration: an in vitro and in vivo study

Background

Concentrated growth factor (CGF), as a natural biomaterial, is known to contain platelets, cytokines, and growth factors to facilitate the healing process, but there has been little information acquired in regenerative endodontics. The purpose of this study was to investigate the effects of CGF on proliferation, migration, and differentiation in human dental stem pulp cells (hDPSCs) exposed to lipopolysaccharide (LPS) in vitro and its potential role in pulp regeneration of the immature teeth in vivo.

Methods

In vitro experiments: CGF-conditioned medium were extracted by freeze-dried method. hDPSCs were isolated and identified. The proliferative potential of hDPSCs with different concentration of CGF and LPS was evaluated by Cell Counting Kit-8. Migration capacity was analyzed by Transwell assays, odonto/osteoblastic differentiation was determined by measuring alkaline phosphatase (ALP) activity using ALP staining, and the extent of mineralization was evaluated by using Alizarin red S staining. The mRNA expression level of DMP-1, DSPP, OPN, Runx2, and OCN were determined by quantitative polymerase chain reaction (qPCR).

In vivo experiments: CGF were used as root canal filling agent of the immature single-rooted teeth in the beagle dogs. The teeth were then radiographed, extracted, fixed, demineralized, and subjected to histologic analyses at 8 weeks. The newly formed dentine-pulp complex and the development of apical foramen were evaluated by the hematoxylin-eosin (HE) and Masson trichrome technique. Soft tissues were analyzed by immunohistochemical staining of vascular endothelial growth factor (VEGF) and Nestin.

Results

In vitro experiments: The cultured cells exhibited the characteristics of mesenchymal stem cell. The treatment of LPS significantly increased the expression of TNF-α, IL-1β, IL-6, and IL-8 in hDPSCs, and CGF inhibited the mRNA expression of IL-8 in LPS-stimulated hDPSCs. The proliferation values of the CGF group in LPS-stimulated hDPSCs were significantly higher than that of the control group from day 3 to day 7 (P < 0.05). In addition, the number of migratory cells of the CGF group was greater than that of the control group at 24 h with or without LPS treatment. ALP activities increased gradually in both groups from day 4 to day 7. The mineralized nodules and the expression of odontogenesis-related genes DMP-1 and DSPP, osteogenesis-related genes OPN, Runx2, and OCN were dramatically enhanced by CGF in LPS-stimulated hDPSCs at days 21 and 28.

In vivo experiments: In CGF treated group, the results of radiograph, HE, and Masson trichrome staining showed a continuing developed tooth of the immature teeth in the beagle dogs (i.e., the ingrowth of soft tissues into the root canal, the thickened internal root dentin walls, and the closed apex), which resembled the normal tooth development in the positive control group. The immunohistochemical staining showed that VEGF and Nestin were both moderately expressed in the regenerated pulp-like tissues which indicating the vascularization and innervation.

Conclusions

CGF has a positive effect on the proliferation, migration, and differentiation of hDPSCs exposed to LPS in vitro, and it can also promote the regeneration of dentine-pulp complex of the immature teeth in the beagle dogs in vivo. Therefore, CGF could be a promising alternative biomaterial in regenerative endodontics.

Modulation of proliferation and differentiation of gingiva‑derived mesenchymal stem cells by concentrated growth factors: Potential implications in tissue engineering for dental regeneration and repair

The aim of the present study was to evaluate the proliferation and osteogenic differentiation ability of gingiva-derived mesenchymal stem cells (GMSCs) cultured with different concentrations of concentrated growth factors (CGF). GMSCs were isolated from gingival connective tissues and characterized by flow cytometry, immunofluorescence staining and immunohistochemical staining. Cell proliferation activity was determined by the MTT assay, and the effect of CGF on MCSCs was detected with the Cell Counting Kit (CCK)-8 assay. Mineralization induction was evaluated by alkaline phosphatase (ALP)-positive cell staining and mineralized nodule formation assay. Dentin matrix acidic phosphoprotein (DMP)1, dentin sialophosphoprotein (DSPP), bone morphogenetic protein (BMP)2 and runt-related transcription factor (RUNX)2 mRNA and protein expression were evaluated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis and western blotting. The flow cytometry, immunofluorescence staining and immunohistochemical staining results indicated that the cultured cells were GMSCs. The MTT assay results revealed that the third-generation gingival stem cells exhibited the highest proliferative capacity, and the CCK-8 results indicated that 10% CGF achieved the most prominent promotion of GMSC proliferation. ALP activity analysis and mineralized nodule assay demonstrated that CGF may successfully induce osteogenic differentiation of GMSCs, whereas RT-qPCR and western blot analyses demonstrated that CGF is involved in the differentiation of GMSCs by regulating the expression of DMP1, DSPP, BMP2 and RUNX2 (P<0.05). In conclusion, CGF were demonstrated to promote the proliferation and osteogenic differentiation of GMSCs. Therefore, CGF may be applied in tissue engineering for tooth regeneration and repair.