Periodontal regeneration by FGF-2 (bFGF) in primate models

Recombinant human fibroblast growth factor and autogenous bone for periodontal regeneration: Alone or in combination? A randomized clinical trial

AIM

To compare the outcomes of therapy using recombinant human fibroblast growth factor (rhFGF)-2 combined with autologous bone grafting (ABG) therapy with those of rhFGF-2 alone and ABG alone in the treatment of periodontal intraosseous defects.

METHODS

Periodontal intraosseous defects were randomized to receive rhFGF-2 therapy + ABG, rhFGF-2 therapy alone, or ABG alone. Periodontal examination and periapical radiography were performed preoperatively and at 3, 6, and 12 months postoperatively.

RESULTS

At the 12 months follow-up, all three groups showed significant improvement in the clinical attachment level (CAL): 5.6 ± 1.6, 5.8 ± 1.7, and 5.2 ± 1.6 mm in the rhFGF-2 + ABG, rhFGF-2 alone, and ABG alone groups, respectively, with no significant inter-group differences (p < .05). rhFGF-2 therapy (alone or in combination) resulted in greater bone defect filling (BDF) (2.3 ± 1.2 mm and 2.6 ± 1.9 mm, respectively) than ABG therapy alone (1.2 ± 1.2 mm). Gingival recession was lesser in the ABG alone (1.2 ± 1.1 mm) and rhFGF-2 + ABG groups (1.4 ± 0.8 mm) than in the rhFGF-2 alone group (2.2 ± 1.2 mm).

CONCLUSION

The results of this study showed that at 12 months postoperatively, all treatments resulted in statistically significant clinical improvements compared to the baseline. From these results, it can be concluded that rhFGF-2 promotes hard tissue regeneration in intraosseous defects.

From Basic Science to Clinical Practice: A Review of Current Periodontal/Mucogingival Regenerative Biomaterials

Periodontitis is a dysbiosis-driven inflammatory disease affecting the tooth-supporting tissues, characterized by their progressive resorption, which can ultimately lead to tooth loss. A step-wise therapeutic approach is employed for periodontitis. After an initial behavioral and non-surgical phase, intra-bony or furcation defects may be amenable to regenerative procedures. This review discusses the regenerative technologies employed for periodontal regeneration, highlighting the current limitations and future research areas. The search, performed on the MEDLINE database, has identified the available biomaterials, including biologicals (autologous platelet concentrates, hydrogels), bone grafts (pure or putty), and membranes. Biologicals and bone grafts have been critically analyzed in terms of composition, mechanism of action, and clinical applications. Although a certain degree of periodontal regeneration is predictable in intra-bony and class II furcation defects, complete defect closure is hardly achieved. Moreover, treating class III furcation defects remains challenging. The key properties required for functional regeneration are discussed, and none of the commercially available biomaterials possess all the ideal characteristics. Therefore, research is needed to promote the advancement of more effective and targeted regenerative therapies for periodontitis. Lastly, improving the design and reporting of clinical studies is suggested by strictly adhering to the Consolidated Standards of Reporting Trials (CONSORT) 2010 statement.

A Case Report of Periodontal Regenerative Therapy Using Recombinant Human Fibroblast Growth Factor 2 and Deproteinized Bovine Bone Mineral with Non-incised Papillae Surgical Approach (NIPSA) for Angular Bone Defect in Patient with Stage III Grade C Periodontitis

This report describes a case of Stage III Grade C periodontitis requiring periodontal regenerative therapy. The patient was a 19-year-old woman who presented with the chief complaint of gingival recession in the incisor region. An initial examination revealed that 45.3% of sites had a probing depth of ≥4 mm and 45.8% bleeding on probing. Radiographic examination showed angular bone resorption in #25, 26, 31, 36, and 46 and horizontal resorption in other regions. Initial periodontal therapy was implemented based on a clinical diagnosis of Stage III Grade C periodontitis (generalized aggressive periodontitis). Occlusal adjustment was also performed at sites showing premature contact (#26 and 36) after suppression of inflammation. Periodontal regenerative therapy using recombinant human fibroblast growth factor (rhFGF) -2 was performed on #25, 26, and 46. Combination therapy with rhFGF-2 and deproteinized bovine bone mineral (DBBM) was performed on #31 and 36. A non-incised papillae surgical approach (NIPSA) was used on #31. Periodontal conditions were then re-evaluated and the patient placed on supportive periodontal therapy. Regenerative therapy using rhFGF-2 and DBBM with NIPSA yielded an improvement in clinical parameters and bone resorption. This improvement has been adequately maintained over a 12-month period. Continued care is needed to maintain stable periodontal conditions.

Synergistic effect of FGF-2 and TGF-β1 on the mineralization of human umbilical cord perivascular cells

OBJECTIVE

Human umbilical cord perivascular cells (HUCPVCs) are derived from the human umbilical cord perivascular tissue and are expected to replace mesenchymal stromal cells in the future. We investigated the synergistic effects of fibroblast growth factor 2 (FGF-2) and transforming growth factor-beta 1 (TGF-β1) on HUCPVC mineralization.

DESIGN

We prepared HUCPVCs with (FGF(+)HUCPVCs) or without FGF-2 (FGF(-)HUCPVCs) in the presence of activated vitamin D3, a bone morphogenic protein inhibitor, and TGF-β1. We examined the cell proliferative capacity, expression of various hard tissue-forming cell gene markers, and mineralization induction ability and identified the crystalline phases of the mineralized nodules.

RESULTS

FGF(+)HUCPVCs exhibited higher intracellular alkaline phosphatase (ALP) gene expression and ALP activity, and their cell proliferation rate was higher than that of FGF(-)HUCPVCs. The expression levels of osteoblast marker genes increased in FGF(+)HUCPVCs, whereas those of elastic fiber and muscle cell markers increased in FGF(-)HUCPVCs. The expression of genes related to matrix vesicle-mediated mineralization was increased in FGF(+)HUCPVCs. While FGF(-)HUCPVCs displayed myofibroblast-like properties and could not induce mineralization, FGF(+)HUCPVCs demonstrated the ability to produce mineralized nodules. The resulting mineralized nodules consisted of hydroxyapatite as the major phase and minor amounts of octacalcium phosphate. The mineralized nodules exhibited the morphological characteristics of bone hydroxyapatite, composed of fibrous hydroxyapatite nanorods and polycrystalline sheets.

CONCLUSION

We found that FGF-2 synergizes with TGF-β1 and is a key factor in the differentiation of HUCPVCs into osteoblast-like cells. Thus, HUCPVCs can potentially serve as a new stem cell source for future bone regeneration and dental treatments.

Effects of combined application of fibroblast growth factor (FGF)-2 and carbonate apatite for tissue regeneration in a beagle dog model of one-wall periodontal defect

Introduction

There has been an increasing desire for the development of predictive periodontal regenerative therapy for severe periodontitis. In this study, we investigated the effect of the combined use of fibroblast growth factor-2 (FGF-2), a drug for periodontal regeneration approved in Japan, and carbonated apatite (CO₃Ap), bioresorbable and osteoconductive scaffold, on periodontal regeneration in beagle dog model of one-wall periodontal defect (severe intraosseous defect) for 24 weeks in comparison with CO₃Ap or vehicle alone.

Methods

One-wall periodontal defects were created (mesiodistal width × depth: 4 × 4 mm) on the mesial portion of the mandibular first molar (M1) of beagle dogs on both side. Mixture of FGF-2 and CO₃Ap, vehicle and CO₃Ap, or vehicle alone were administered to the defects and designated as groups FGF-2+CO₃Ap, CO₃Ap, and control, respectively. To assess the periodontal regeneration, radiographic analysis over time for 24 weeks, and micro computed tomography (μCT) and histological evaluation at 6 and 24 weeks were performed.

Results

For the regenerated tissue in the defect site, the mineral content of the FGF-2+CO₃Ap group was higher than that of the CO₃Ap group in the radiographic analysis at 6-24 weeks. In the context of new bone formation and replacement, the FGF-2+CO₃Ap group exhibited significantly greater new bone volume and smaller CO₃Ap volume than the CO₃Ap group in the μCT analysis at 6 and 24 weeks. Furthermore, the density of the new bone in the FGF-2+CO₃Ap group at 24 weeks was similar to those in the control and CO₃Ap groups. Histological evaluation revealed that the length of the new periodontal ligament and cementum in the FGF-2+CO₃Ap group was greater than that in the CO₃Ap group at 6 weeks. We also examined the effect of the combined use of the FGF-2 and CO₃Ap on the existing bone adjacent to the defect and demonstrated that the existing bone height and volume in the FGF-2+CO₃Ap group remained significantly greater than those in the CO₃Ap group.

Conclusion

This study demonstrated that the combination of FGF-2 and CO₃Ap was effective not only in enhancing new bone formation and replacing scaffold but also in maintaining the existing bone adjacent to the defect site in a beagle dog model of one-wall periodontal defect. Additionally, new periodontal tissues induced by FGF-2 and CO₃Ap may follow a maturation process similar to that formed by spontaneous healing. This suggests that the combined use of FGF-2 and CO₃Ap would promote periodontal regeneration in severe bony defects of periodontitis patient.

The role of rhFGF-2 in periodontal defect bone fill: A systematic review of the literature

BACKGROUND

Growth factors have been used with success in periodontal regeneration, especially in intrabony defects. Among those, the recombined form of fibroblast growth factor-2 (rhFGF-2) has been also examined.

OBJECTIVE

To address the outcomes of periodontal regeneration using rhFGF-2 alone or in combination with bone substitutes primarily in terms of Radiographic Bone Fill (RBF%) and secondary Probing Pocket Depth (PPD), and Probing Attachment Levels (PAL).

MATERIAL AND METHODS

A search in MEDLINE and EMBASE using the Ovid interface was conducted from 2000 up to and including the 12th of November 2022. Starting from the initially identified 1289 articles, 34 studies were selected for further analysis. Following the full-text screening, 7 of the 34 studies met the inclusion criteria and thus were included in the systematic review after assessing their quality according to the Newcastle-Ottawa scale (NOS). Clinical and radiographic results (bone gain, pocket depth, and clinical attachment level) after the application of FGF-2 alone or in combination with different carriers were studied in patients with intrabony defects of at least one wall and pocket depth greater than 4 mm.

RESULTS

Primary outcomes: RBF% was higher in studies using a combination of rhFGF-2 and bone substitutes (74.6 ± 20.0%) compared to others using the specific growth factor alone or negative controls (22.7 ± 20.7%). In terms of secondary outcomes, the analysis failed to show an additional benefit from the use of the rhFGF-2 alone or in combination with bone substitutes.

CONCLUSION

rhFGF-2 can improve RBF% in the treatment of periodontal defects, especially when it is used in combination with a bone substitute.

An exploratory clinical trial to evaluate the safety and efficacy of combination therapy of REGROTH® and Cytrans® granules for severe periodontitis with intrabony defects

Introduction

Currently, flap operation (FOP) using REGROTH® (0.3% basic fibroblast growth factor [FGF-2]) is the standard treatment for periodontal regenerative therapy in Japan. However, the periodontal tissue regenerative effect with REGROTH® monotherapy is inadequate for severe alveolar bone defects. Therefore, in this study, we evaluated the safety and effectiveness of periodontal regenerative therapy for patients with severe periodontitis using REGROTH® (test medicine) combined with Cytrans® Granules (test device: carbonated apatite granules), which is a new artificial bone.

Methods

The study participants included 10 patients with severe periodontitis (mean age: 47.4 years). All participants provided written informed consents. In each patient, the intrabony defect site (mean bone defect depth: 5.7 mm) was defined as the test site. FOP was performed for the test site after the baseline investigation; moreover, the test medicine and test device were administered simultaneously. Furthermore, the observation of subjects’ general condition and test sites was conducted and the blood, urine, and periodontal tissue tests were performed up to 36 weeks after FOP. The rate of bone increase (%), clinical attachment level (CAL), probing pocket depth (PPD), bleeding on probing (BOP), tooth mobility (Mo), width of keratinized gingiva (KG), gingival recession (REC), gingival index (GI), and plaque index (PlI) were evaluated during the periodontal tissue investigation.

Results

As the primary endpoint, no adverse events related to the test medicine and test device occurred during the entire observation period of this study. Regarding the secondary endpoints, there was a significant increase in new alveolar bone (p = 0.003) and CAL acquisition (p = 0.001) as well as decrease in PPD (p = 0.002) and BOP (p = 0.016) at 36 weeks after administration of the test medicine and test device compared with the preoperative values. Furthermore, at 36 weeks after surgery, the Mo, GI, and PlI decreased to preoperative levels at 40%, 60%, and 30% of sites, respectively. However, at 36 weeks after surgery, there was no difference in KG and REC compared with their preoperative values.

Conclusions

The safety of periodontal regenerative therapy using the test medicine in combination with the abovementioned test device was confirmed. In addition, it was suggested that this periodontal regenerative therapy is effective for tissue regeneration in severe alveolar bone defects.

This clinical trial was conducted after registering and publicizing as a specified clinical trial in the Japan registry of clinical trials (jRCTs051190045).

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The safety of flap operation using 0.3% FGF-2 and carbonated apatite was confirmed.

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The administration of 0.3% FGF-2 and carbonated apatite improved periodontitis.

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Combining 0.3% FGF-2 and carbonated apatite for severe alveolar bone defects.

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Periodontal regenerative therapy combining both could be effective.

Prognostic factors affecting periodontal regenerative therapy using recombinant human fibroblast growth factor-2: A 3-year cohort study

Introduction

Fibroblast growth factor-2 (FGF-2) has been reported to promote periodontal tissue regeneration. However, no study has investigated the long-term prognosis of periodontal regenerative therapy using FGF-2 to date. The aim of this study was to observe the long-term outcomes as well as to investigate the factors affecting the prognosis of periodontal regenerative therapy using FGF-2.

Methods

Sixty intrabony defects were prospectively investigated for three years after periodontal regenerative therapy with recombinant human FGF-2 (rhFGF-2) by evaluating probing pocket depth (PPD) and radiographic bone defect depth (RBD). The factors influencing RBD were assessed by conducting a multivariate linear regression analysis after adjusting for confounders.

Results

The mean age of the participants was 62.4 ± 13.4 years, and baseline PPD and RBD were 6.1 ± 1.9 mm and 4.5 ± 1.8 mm, respectively. At six months, one year, and three years after surgery, PPD and RBD had significantly improved to 4.2 ± 1.7, 3.7 ± 1.4, 4.0 ± 1.9 mm and to 3.08 ± 2.05, 2.73 ± 1.90, 2.51 ± 2.15 mm, respectively. At the three-year examination, a significant positive association was deteced between RBD reduction and RBD at baseline, while the association was not significant between RBD reduction and the radiographic bony angle, number of bony walls of the defect, or the furcation involvement at baseline.

Conclusions

rhFGF-2 was effective for alveolar bone regeneration in patients with periodontitis and maintained the improved parameters over the three-year observation period. The radiographic bone defect depth at baseline was found to be the factor affecting the periodontal regenerative therapy using rhFGF-2 in the intrabony defects.

Trial registration number

UMIN000027979.

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Mid-term observation following periodontal regenerative therapy using rhFGF-2.

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Reductions in PPD and radiographic defect depth were maintained for 3 years.

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Evaluation of prognostic factors of rhFGF-2 application in intrabony defects.

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Preoperative radiographic defect depth predicts postoperative bone fill.

Development and regeneration of periodontal supporting tissues

Periodontal tissues, including gingiva, cementum, periodontal ligament, and alveolar bone, play important roles in oral health. Under physiological conditions, periodontal tissues surround and support the teeth, maintaining the stability of the teeth and distributing the chewing forces. However, under pathological conditions, with the actions of various pathogenic factors, the periodontal tissues gradually undergo some irreversible changes, that is, gingival recession, periodontal ligament rupture, periodontal pocket formation, alveolar bone resorption, eventually leading to the loosening and even loss of the teeth. Currently, the regenerations of the periodontal tissues are still challenging. Therefore, it is necessary to study the development of the periodontal tissues, the principles and processes of which can be used to develop new strategies for the regeneration of periodontal tissues. This review summarizes the development of periodontal tissues and current strategies for periodontal healing and regeneration.

Priming strategies for controlling stem cell fate: Applications and challenges in dental tissue regeneration

Mesenchymal stromal cells (MSCs) have attracted intense interest in the field of dental tissue regeneration. Dental tissue is a popular source of MSCs because MSCs can be obtained with minimally invasive procedures. MSCs possess distinct inherent properties of self-renewal, immunomodulation, proangiogenic potential, and multilineage potency, as well as being readily available and easy to culture. However, major issues, including poor engraftment and low survival rates in vivo, remain to be resolved before large-scale application is feasible in clinical treatments. Thus, some recent investigations have sought ways to optimize MSC functions in vitro and in vivo. Currently, priming culture conditions, pretreatment with mechanical and physical stimuli, preconditioning with cytokines and growth factors, and genetic modification of MSCs are considered to be the main strategies; all of which could contribute to improving MSC efficacy in dental regenerative medicine. Research in this field has made tremendous progress and continues to gather interest and stimulate innovation. In this review, we summarize the priming approaches for enhancing the intrinsic biological properties of MSCs such as migration, antiapoptotic effect, proangiogenic potential, and regenerative properties. Challenges in current approaches associated with MSC modification and possible future solutions are also indicated. We aim to outline the present understanding of priming approaches to improve the therapeutic effects of MSCs on dental tissue regeneration.

Inhibition of c-Jun N-terminal kinase signaling promotes osteoblastic differentiation of periodontal ligament stem cells and induces regeneration of periodontal tissues

OBJECTIVES

Few clinical treatments to regenerate periodontal tissue lost due to severe endodontic and periodontal disease have yet been developed. Therefore, the development of new treatment methods for the regeneration of periodontal tissue is expected. The purpose of this study was to investigate the effects of a c-Jun N-terminal kinase (JNK) inhibitor, SP600125, on the osteoblastic differentiation of periodontal ligament stem cells (PDLSCs) in vitro, and the function of SP600125 on the regeneration of alveolar bone in vivo.

DESIGN

Alizarin red S staining, quantitative RT-PCR, and western blotting analysis was performed to determine whether SP600125 affects osteoblastic differentiation of human PDLSCs (HPDLSCs) and bone-related intracellular signaling. The effect of SP600125 on the regeneration of alveolar bone was assessed by using a rat periodontal defect model. The healing of periodontal defects was evaluated using micro-CT scans and histological analysis.

RESULTS

SP600125 promoted the osteoblastic differentiation such as Alizarin red S-positive mineralized nodule formation and the expression of osteoblast-related genes in HPDLSCs under osteogenic conditions. In addition, this inhibitor upregulated the BMP2 expression and the phosphorylation of Smad1/5/8 in HPDLSCs under the same conditions. The inhibition of Smad1/5/8 signaling by LDN193189 suppressed the SP600125-induced osteoblastic differentiation of HPDLSCs. Furthermore, the application of SP600125 promoted the regeneration of not only alveolar bone but also PDL tissue in periodontal defects.

CONCLUSION

This study suggested that inhibition of JNK signaling promotes the osteoblastic differentiation of HPDLSCs through BMP2-Smad1/5/8 signaling, leading to the regeneration of periodontal tissues such as alveolar bone and PDL tissue.

Efficacy of periodontal minimally invasive surgery with and without regenerative materials for treatment of intrabony defect: a randomized clinical trial

OBJECTIVES

The minimally invasive surgical technique was modified in suture (MISTms) in this study. The trial was to determine the efficacy of MISTms with and without regenerative materials for the treatment of intrabony defect and to identify factors influencing 1-year clinical attachment level (CAL) gain.

METHODS

Thirty-six patients with interdental intrabony defects were randomly assigned to MISTms (MISTms alone, 18) or MISTms plus deproteinized bovine bone mineral and collagen membrane (MISTms combined, 18). Wound healing was evaluated by early healing index (EHI) at 1, 2, 3, and 6 weeks. Probing depth (PD), CAL, gingival recession, radiographic defect depth, and distance from the base of defect to the cementoenamel junction were recorded at baseline and 1 year postoperatively. A one-year composite outcome measure based on the combination of CAL gain and post-surgery PD was evaluated. Factors influencing 1-year CAL gain were analyzed.

RESULTS

Fifteen patients in MISTms-alone and 16 in the MISTms-combined group finished the study. The MISTms-alone group showed significantly better wound healing at 1 week. CAL significantly gained in the MISTms-alone and MISTms-combined group, with 2.53 ± 1.80 mm and 2.00 ± 1.38 mm respectively. The radiographic bone gain was 3.00 ± 1.56 mm and 3.85 ± 1.69 mm respectively. However, there were no significant differences between the two groups about 1-year outcomes. Lower EHI (optimal wound healing) and more baseline CAL positively influenced 1-year CAL gain.

CONCLUSIONS

MISTms is an effective treatment for intrabony defects. The regenerative materials do not show an additional effect on 1-year outcomes. Early wound healing and baseline CAL are factors influencing 1-year CAL gain.

CLINICAL RELEVANCE

MISTms with and without regenerative materials are both effective treatments for intrabony defect.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: ChiCTR2100043272.

Healing of Experimental Periodontal Defects Following Treatment with Fibroblast Growth Factor-2 and Deproteinized Bovine Bone Mineral

The aim of this study was to investigate the effects of fibroblast growth factor (FGF)-2 used in combination with deproteinized bovine bone mineral (DBBM) on the healing of experimental periodontal defects. Periodontal defects created in rats were treated by FGF-2, DBBM, FGF-2 + DBBM, or left unfilled. Microcomputed tomography, histological, and immunohistochemical examinations were used to evaluate healing. In vitro cell viability/proliferation on DBBM with/without FGF-2 was assessed by WST-1. Cell behavior was analyzed using scanning electron and confocal laser scanning microscopy. Osteogenic differentiation was evaluated by staining with alkaline phosphatase and alizarin red. Bone volume fraction was significantly greater in FGF-2 and FGF-2 + DBBM groups than in other groups at 2 and 4 weeks postoperatively. In histological assessment, newly formed bone in FGF-2 and FGF-2 + DBBM groups appeared to be greater than other groups. Significantly greater levels of proliferating cell nuclear antigen-, vascular endothelial growth factor-, and osterix-positive cells were observed in FGF-2 and FGF-2 + DBBM groups compared to Unfilled group. In vitro, addition of FGF-2 to DBBM promoted cell viability/proliferation, attachment/spreading, and osteogenic differentiation. The combination therapy using FGF-2 and DBBM was similarly effective as FGF-2 alone in the healing of experimental periodontal defects. In certain bone defect configurations, the combined use of FGF-2 and DBBM may enhance healing via promotion of cell proliferation, angiogenesis, and osteogenic differentiation.

Periodontal Regenerative Therapy with Recombinant Human Fibroblast Growth Factor-2 and Deproteinized Bovine Bone Mineral in Patient with Chronic Periodontitis: An 18-month Follow-up Report

This report describes a case of generalized chronic periodontitis requiring periodontal regenerative therapy. The patient was a 62-year-old man who presented with the chief complaint of gingival swelling in the molar region. An initial examination revealed that 31.6% of sites had a probing depth of ≥4 mm and 18.5% bleeding on probing. Radiographic examination revealed vertical bone resorption in #14, 25, 26, 27, 32, 37, 45, and 47, and horizontal resorption in other regions. Based on a clinical diagnosis of moderate chronic periodontitis, initial periodontal therapy consisting of plaque control and scaling and root planing was performed. Occlusal adjustment of premature contact sites was performed after inflammation was suppressed. Surgical periodontal therapy was subsequently performed at selected sites. Periodontal regenerative therapy using recombinant human fibroblast growth factor (rhFGF)-2 was performed on #14, 25, 26, 32, and 37. Combination therapy with rhFGF-2 and deproteinized bovine bone mineral (DBBM) was performed on #45 and 47. Other sites with residual periodontal pockets were treated by open flap debridement, and #27 was extracted due to a bone defect exceeding the root apex. Progress was then reevaluated and the patient placed on supportive periodontal therapy. Periodontal regenerative therapy using rhFGF-2 in combination with DBBM resulted in an improvement in clinical parameters and vertical bone resorption. This improvement has been adequately maintained over an 18-month period. The periodontal treatment provided resulted in a marked improvement in the patient's oral health-related quality of life.

Surgical Periodontal Therapy with Recombinant Human Fibroblast Growth Factor-2 in Treatment of Chronic Periodontitis: A Case Report with 2-year Follow-up

We report a case of generalized chronic periodontitis requiring periodontal regenerative therapy. The patient was a 53-year-old woman who presented with the chief complaint of gingival swelling. An initial examination revealed 31.5% of sites with a probing depth of ≥4 mm and 46.3% with bleeding on probing. Radiographic examination showed vertical bone resorption in tooth #33. Horizontal adsorption was also observed in other areas. Based on a clinical diagnosis of severe generalized chronic periodontitis, initial periodontal therapy consisting of plaque control, scaling and root planing, occlusal adjustment, caries treatment, and splint placement was performed. After re-evaluation, surgical periodontal treatment was performed at selected sites. Periodontal regeneration therapy with recombinant human fibroblast growth factor (rhFGF)-2 was performed at #33. Two other sites (#14, 15), which had residual periodontal pockets, were treated by open-flap debridement. After re-evaluation, the patient was placed on a maintenance program. Periodontal regenerative therapy with rhFGF-2 resulted in an improvement in angular bone resorption, which has been properly maintained for 2 years. Continued care is needed to maintain stable periodontal conditions.

Hard Dental Tissues Regeneration-Approaches and Challenges

With the development of the modern concept of tissue engineering approach and the discovery of the potential of stem cells in dentistry, the regeneration of hard dental tissues has become a reality and a priority of modern dentistry. The present review reports the recent advances on stem-cell based regeneration strategies for hard dental tissues and analyze the feasibility of stem cells and of growth factors in scaffolds-based or scaffold-free approaches in inducing the regeneration of either the whole tooth or only of its component structures.

Efficacy of recombinant human fibroblast growth factor 2 impregnated absorbable collagen membrane in the treatment of Miller's Class I and II gingival recession defects Preliminary results from the first in human clinical trial

Aims:

This study was a single-arm trial to obtain preliminary data on the efficacy of collagen membranes impregnated with recombinant human fibroblast growth factor-2 (rhFGF-2) in the treatment of Miller's Class I and II gingival recessions.

Materials and Methods:

Twenty-one individuals (34 sites) presenting with localized Miller's Class I and II gingival recessions were included in this study. Following a standard surgical protocol, rhFGF-2-impregnated membranes were placed in sites with gingival recession. Clinical parameters such as width of keratinized gingiva (wKG), recession depth (RD), and probing depth were measured at baseline and after therapy completion at 3 and 6 months.

Results:

Most of the sites exhibited favorable clinical healing; the most common complications were persistent edematous and inflamed gingivae beyond 1 week (n = 3), development of residual periodontal pockets (n = 2), and no reduction in RDs (n = 2). Significant improvements in wKG and RD were noted from baseline to 6 months.

Conclusion:

rhFGF-2-impregnated collagen membranes showed promising results in terms of increasing the wKG and recession coverage. A comparison with other standard therapies and agents in subsequent trials may shed more light on the clinical efficacy of this material.

Current and future trends in periodontal tissue engineering and bone regeneration

Periodontal tissue engineering involves a multi-disciplinary approach towards the regeneration of periodontal ligament, cementum and alveolar bone surrounding teeth, whereas bone regeneration specifically applies to ridge reconstruction in preparation for future implant placement, sinus floor augmentation and regeneration of peri-implant osseous defects. Successful periodontal regeneration is based on verifiable cementogenesis on the root surface, oblique insertion of periodontal ligament fibers and formation of new and vital supporting bone. Ultimately, regenerated periodontal and peri-implant support must be able to interface with surrounding host tissues in an integrated manner, withstand biomechanical forces resulting from mastication, and restore normal function and structure. Current regenerative approaches utilized in everyday clinical practice are mainly guided tissue/bone regeneration-based. Although these approaches have shown positive outcomes for small and medium-sized defects, predictability of clinical outcomes is heavily dependent on the defect morphology and clinical case selection. In many cases, it is still challenging to achieve predictable regenerative outcomes utilizing current approaches. Periodontal tissue engineering and bone regeneration (PTEBR) aims to improve the state of patient care by promoting reconstitution of damaged and lost tissues through the use of growth factors and signaling molecules, scaffolds, cells and gene therapy. The present narrative review discusses key advancements in PTEBR including current and future trends in preclinical and clinical research, as well as the potential for clinical translatability.

Treatment of Chronic Periodontitis with Recombinant Human Fibroblast Growth Factor-2 and Deproteinized Bovine Bone Mineral in Wide Intrabony Defects:12-month Follow-up Case Series

Clinical use of 0.3% recombinant human fibroblast growth factor (rhFGF)-2 for periodontal regeneration received formal approval in Japan in 2016. The combination of growth factor and bone graft material is used to enhance periodontal healing in regenerative therapy. The exact effects of combination therapy on periodontal healing remain unknown, however. Here, we report three cases of chronic periodontitis treated with the combination of rhFGF-2 and deproteinized bovine bone mineral (DBBM). Following initial periodontal therapy, periodontal regenerative therapy using rhFGF-2 in combination with DBBM was performed to treat wide intrabony defects. Periodontal parameters and radiographic bone fill were reevaluated at 3 months, 6 months, and 1 year postoperatively. Oral health-related quality of life (OHRQL) was assessed as a patient-reported measure of outcome. At 1 year postoperatively, probing pocket depth and clinical attachment level showed a significant improvement in comparison with at baseline. An improvement was also noted in radiographic evidence of bone fill and total OHRQL scores. Combination therapy yielded clinically favorable results in the present cases.

Efficacy of FGF-2 in Periodontal Regeneration in a Case of Severe Intrabony Defect and Furcation Involvement With 15-Month Follow-Up

INTRODUCTION

Several studies have demonstrated that basic fibroblast growth factor (FGF-2) is one of the most effective growth factors for periodontal regeneration. The Ministry of Health, Labor and Welfare in Japan have approved 0.3% human recombinant FGF-2 for periodontal regeneration, and it has been commercially available since 2016. In this case report, a patient was treated with this periodontal regenerative medicine and demonstrated success at 15-month follow-up, as confirmed by dental X-ray and on cone-beam computed tomography (CBCT).

CASE PRESENTATION

A 42-year-old woman with a one by two walled intrabony defect and Class III furcation involvement in tooth #19, and Class II furcation involvement in tooth #18 (lingual) underwent periodontal regenerative surgery with FGF-2 without any bone graft materials. Favorable clinical and radiographic outcomes were noted 15 months after the procedure. The vertical bone defect in tooth #19 showed a clinical attachment level gain of 8 mm. Moreover, CBCT analysis revealed considerable new bone formation in the Class II furcation involvement in tooth #18 and limited bone formation in the Class III furcation involvement in tooth #19.

CONCLUSIONS

This case report indicates that FGF-2 showed a positive outcome in terms of periodontal regeneration in a case of one by two wall intrabony defects with Class III furcation involvement. A complete recovery of Class II furcation involvement was observed without artificial bone graft materials.

Enhancement of cell proliferation and motility of mammalian cells grown in co-culture with Pichia pastoris expressing recombinant human FGF-2

Many studies examining the biological function of recombinant proteins and their effects on the physiology of mammalian cells stipulate that the proteins be purified before being used as therapeutic agents. In this study, we explored the possibility of using unpurified recombinant proteins to treat mammalian cells. The recombinant protein was used directly from the expression source and the biological function was compared to purified commercially available, equivalent protein. The model for this purpose was recombinant FGF-2, expressed by Pichia pastoris, which was used to treat the murine fibroblast cell line, NIH/3T3. We generated a P. pastoris strain (yHL11) that constitutively secreted a biologically active recombinant FGF-2 protein containing an N-terminal c-myc epitope (Myc-FGF-2). Myc-FGF-2 was then used without purification either a) in the form of conditioned mammalian cell culture medium or b) during co-cultures of yHL11 with NIH/3T3 to induce higher proliferation and motility of NIH/3T3 cells. The effects of Myc-FGF-2 on cell physiology were comparable to commercially available FGF-2. To our knowledge, this is the first time the physiology of cultured mammalian cells had been successfully altered with a recombinant protein secreted by P. pastoris while the two species shared the same medium and culture conditions. Our data demonstrated the biological activity of unpurified recombinant FGF-2 on NIH/3T3 cells and provided a foundation for directly using unpurified recombinant proteins expressed by P. pastoris with mammalian cells, potentially as wound-healing therapeutics.

Poly lactic-co-glycolic acid scaffold loaded with plasmid DNA encoding fibroblast growth factor-2 promotes periodontal ligament regeneration of replanted teeth

OBJECTIVE

This study investigated the effects of poly lactic-co-glycolic acid (PLGA) loaded with plasmid DNA encoding fibroblast growth factor-2 (pFGF-2) on human periodontal ligament cells (hPDLCs) in vitro and evaluated the ability of the PLGA/pFGF-2 scaffold to promote periodontal ligament (PDL) regeneration in a beagle dog teeth avulsion animal model.

BACKGROUND

Growth factor and scaffold play important roles in PDL regeneration. PLGA is a kind of biodegradable and biocompatible polymer that can be used as a carrier to deliver growth factors or genes. FGF-2 can induce potent proliferative responses, promote cell migration and regulate the production of extracellular matrix. Therefore, a gene-activated matrix composed of scaffold and genes is supposed to be a superior approach for promoting tissue regeneration.

METHODS

In this study, PLGA and PLGA/pFGF-2 scaffolds were fabricated using electrospinning. The characterization of scaffolds was shown by scanning electron microscope (SEM) and transmission electron microscope (TEM). dsDNA HS was used to test the plasmid release of PLGA/pFGF-2 scaffold. The viability and proliferation of hPDLCs on the two kinds of scaffolds were evaluated by the CCK-8 assay, and the expression of collagen I and scleraxis were analysed by RT-qPCR. The roots of avulsed teeth were covered by the two types of scaffolds and replanted into the alveolar pockets in beagles. Haematoxylin-eosin and Masson staining were used to evaluate the effects of PLGA/pFGF-2 scaffold on promoting PDL regeneration.

RESULTS

The smooth and uniform fibres can be observed in both scaffolds, and the plasmids were randomly distributed in the PLGA/pFGF-2 scaffold. dsDNA HS analysis demonstrated that the PLGA/pFGF-2 scaffold released up to 123 ng pFGF-2 over 21 days in a sustained manner without any obvious burst release. The PLGA/pFGF-2 scaffold promoted the proliferation of hPDLCs and increased the expression levels of collagen I and scleraxis compared with PLGA scaffold. Animal experiments showed that more regular PDL-like tissues and less root surface resorption occurred in the PLGA/pFGF-2 scaffold group compared with the PLGA scaffold group.

CONCLUSIONS

The PLGA/pFGF-2 scaffold promoted hPDLCs proliferation and facilitated periodontal ligament-related differentiation. The PLGA/pFGF-2 scaffold possesses excellent biological characteristics and could be used as a promising biomaterial for improving the treatment prognosis of replanted tooth.

Mesenchymal stem cell-based tissue regeneration therapies for periodontitis

Periodontitis is commonly observed and is an important concern in dental health. It is characterized by a multifactorial etiology, including imbalance of oral microbiota, mechanical stress, and systemic diseases such as diabetes mellitus. The current standard treatments for periodontitis include elimination of the microbial pathogen and application of biomaterials for treating bone defects. However, the periodontal tissue regeneration via a process consistent with the natural tissue formation process has not yet been achieved. Developmental biology studies state that periodontal tissue is composed of neural crest-derived ectomesenchyme. To elucidate the process of periodontal regeneration, it is essential to understand the developmental background and intercellular cross-talk. Several recent studies have reported the efficacy of transplantation of mesenchymal stem cells for periodontal tissue regeneration. In this review, we discuss the basic knowledge of periodontal tissue regeneration using mesenchymal stem cells and highlight the potential of stem cell-based periodontal regenerative medicine.

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Neural crest cells regulate the development and homeostasis of periodontal tissues.

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Dental mesenchymal stem cells (MSCs) are used for treating alveolar bone defects.

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Non-odontogenic MSCs can be investigated for periodontal tissue regeneration.

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Using appropriate growth factors and scaffold may improve periodontium regeneration.

Treatment of intrabony periodontal defects using rhFGF-2 in combination with deproteinized bovine bone mineral or rhFGF-2 alone: A 6-month randomized controlled trial

Aim

To evaluate the use of recombinant human fibroblast growth factor (rhFGF)‐2 in combination with deproteinized bovine bone mineral (DBBM) compared with rhFGF‐2 alone, in the treatment of intrabony periodontal defects.

Materials and Methods

Patients with periodontitis who had received initial periodontal therapy and had intrabony defects of ≥ 3 mm in depth were enrolled. Sites were randomly assigned to receive a commercial formulation of 0.3% rhFGF‐2 + DBBM (test) or rhFGF‐2 alone (control). Clinical parameters and a patient‐reported outcome measure (PROM) were evaluated at baseline and at 3 and 6 months postoperatively.

Results

Twenty‐two sites in each group were evaluated. A significant improvement in clinical attachment level (CAL) from baseline was observed in both groups at 6 months postoperatively. CAL gain was 3.16 ± 1.45 mm in the test group and 2.77 ± 1.15 mm in the control group, showing no significant difference between groups. Radiographic bone fill was significantly greater in the test group (47.2%) than in the control group (29.3%). No significant difference in PROM between groups was observed.

Conclusions

At 6 months, no significant difference in CAL gain or PROM between the two treatments was observed, although combination therapy yielded an enhanced radiographic outcome.

Knowledge, attitude, and practice toward regenerative endodontics and factors affecting its practice among dental practitioners in Ajmer city: A cross-sectional study

Background

Regenerative methods, which regenerate the damaged structures, are one of the treatment methods in endodntics. This conservative approach helps to generate cells that may produce the lost structure. Thus, the aim of this study was to explore the knowledge, attitude, and practice among dental practitioners toward regenerative endodontics and factors affecting their knowledge, attitude, and practice.

Materials and Methods

It was a cross-sectional questionnaire study conducted in the month of June-August 2018 in Ajmer city. Permission to conduct the study was obtained from JLN Medical College and Hospital, Department of Dentistry. A total of 100 clinics were visited and face-to-face interview schedule was conducted. A total of 123 dental practitioners were interviewed. A 26 item questionnaire was generated to measure knowledge, attitude, and practice of dental professionals regarding regenerative endodontics.

Results

63% of study participants had poor knowledge scores. Majority of study participants 83 (67%) had poor attitude scores. On applying Pearson's correlation, it was determined that the knowledge regarding regenerative endodontics was significantly (P ≤ 0.001) ** correlated to the attitude among study participants. On applying Chi-square test, it was assessed that the knowledge and practice among study participants were significantly (P = 0.041*) and (P = 0.001**) associated with gender of study participants.

Conclusion

From above results, it is concluded that study participants have poor knowledge, attitude, and practice regarding regenerative endodontics. The knowledge regarding regenerative endodontics was significantly associated with the attitude of study participants. Participants with Masters of Dental Surgery (MDS) degree had a significant effect on the knowledge regarding the regenerative endodontics. Endodontic specialty has a significant effect on the attitude of study subjects.

New Perspectives in the Use of Biomaterials for Periodontal Regeneration

Periodontitis is a disease with a high prevalence among adults. If not treated, it can lead to loss of teeth. Periodontal therapy aims at maintaining patient’s teeth through infection control and correction of non-maintainable anatomies including—when possible—regeneration of lost periodontal tissues. The biological regenerative potential of the periodontium is high, and several biomaterials can be utilized to improve the outcome of periodontal therapy. Use of different natural and synthetic materials in the periodontal field has been studied for many years. The main materials used today in periodontology analyzed in this review are: Resorbable and non-resorbable barrier membranes; autogenous, allogeneic, xenogeneic, and alloplastic bone substitutes; biological agents, such as amelogenins; platelet-derived growth factor; bone morphogenic proteins; rh fibroblast growth factor 2; teriparatide hormone; platelet concentrates; and 3D scaffolds. With the development of new surgical techniques some concepts on periodontal regeneration that were strictly applied in the past seem to be not so critical today. This can have an impact on the materials that are needed when attempting to regenerate lost periodontal structures. This review aims at presenting a rationale behind the use of biomaterials in modern periodontal regeneration

Histologic evidence of periodontal regeneration in furcation defects: a systematic review

OBJECTIVE

To systematically review the available histologic evidence on periodontal regeneration in class II and III furcations in animals and humans.

MATERIALS AND METHODS

A protocol including all aspects of a systematic review methodology was developed including definition of the focused question, defined search strategy, study inclusion criteria, determination of outcome measures, screening methods, data extraction and analysis, and data synthesis. The focused question was defined as follows: "What is the regenerative effect obtained by using or not several biomaterials as adjuncts to open flap surgery in the treatment of periodontal furcation defects as evaluated in animal and human histological studies?"

SEARCH STRATEGY

Using the MEDLINE database, the literature was searched for articles published up to and including September 2018: combinations of several search terms were applied to identify appropriate studies. Reference lists of review articles and of the included articles in the present review were screened. A hand search of the most important dental journals was also performed.

CRITERIA FOR STUDY SELECTION AND INCLUSION

Only articles published in English describing animal and human histological studies evaluating the effect of surgical treatment, with or without the adjunctive use of potentially regenerative materials (i.e., barrier membranes, grafting materials, growth factors/proteins, and combinations thereof) for the treatment of periodontal furcation defects were considered. Only studies reporting a minimum of 8 weeks healing following reconstructive surgery were included. The primary outcome variable was formation of periodontal supporting tissues [e.g., periodontal ligament, root cementum, and alveolar bone, given as linear measurements (in mm) or as a percentage of the instrumented root length (%)] following surgical treatment with or without regenerative materials, as determined histologically/histomorphometrically. Healing type and defect resolution (i.e., complete regeneration, long junctional epithelium, connective tissue attachment, connective tissue adhesion, or osseous repair) were also recorded.

RESULTS

In animals, periodontal regeneration was reported in class II and III defects with open flap debridement alone or combined with various types of bone grafts/bone substitues, biological factors, guided tissue regeneration, and different combinations thereof. The use of biological factors and combination approaches provided the best outcomes for class II defects whereas in class III defects, the combination approaches seem to offer the highest regenerative outcomes. In human class II furcations, the best outcomes were obtained with DFDBA combined with rhPDGF-BB and with GTR. In class III furcations, evidence from two case reports indicated very limited to no periodontal regeneration.

CONCLUSIONS

Within their limits, the present results suggest that (a) in animals, complete periodontal regeneration has been demonstrated in class II and class III furcation defects, and (b) in humans, the evidence for substantial periodontal regeneration is limited to class II furcations.

CLINICAL RELEVANCE

At present, regenerative periodontal surgery represents a valuable treatment option only for human class II furcation defects but not for class III furcations.

The effect of leukocyte-platelet-rich fibrin on bone morphogenetic protein-2 and insulin-like growth factor-1 levels in patients with chronic periodontitis: a randomized split mouth clinical trail

The present study evaluates the effects of leukocyte-platelet-rich fibrin (L-PRF) combined with open flap debridement (OFD) on clinical parameters and growth factors levels (GFL) in chronic periodontitis (CP) patients. This trial was registered at clinicaltrials.gov as NCT02594605. 16 patients (32 sites) with chronic periodontitis who had at least two areas of horizontal bone loss, were treated with OFD alone or L-PRF with OFD (OFD + L-PRF). GFL in gingival crevicular fluid (GCF) were analyzed at baseline, 1 week, 2 weeks and 4 weeks after operation. Probing depth (PD) and clinical attachment level (CAL) were measured at baseline and 6 months postoperatively. PD reduction and CAL gain were significantly higher in the OFD + L-PRF sites than in OFD sites. OFD + L-PRF group showed significantly increased bone morphogenetic protein-2 and insulin-like growth factor-1 at 2 weeks compared with baseline. L-PRF combined with OFD significantly increases GFL and thus, it enhances the periodontal healing on CP patients.

Topical application of bFGF on acid-conditioned and non-conditioned dentin: effect on cell proliferation and gene expression in cells relevant for periodontal regeneration

Periodontal regeneration is still a challenge in terms of predictability and magnitude of effect. In this study we assess the biological effects of combining chemical root conditioning and biological mediators on three relevant cell types for periodontal regeneration.

Acceleration of Fracture Healing by Overexpression of Basic Fibroblast Growth Factor in the Mesenchymal Stromal Cells

In this study, we engineered mesenchymal stem cells (MSCs) to over‐express basic fibroblast growth factor (bFGF) and evaluated its effects on fracture healing. Adipose‐derived mouse MSCs were transduced to express bFGF and green fluorescence protein (ADSC^bFGF‐GFP). Closed‐femoral fractures were performed with osterix‐mCherry reporter mice of both sexes. The mice received 3 × 10⁵ ADSCs transfected with control vector or bFGF via intramuscular injection within or around the fracture sites. Mice were euthanized at days 7, 14, and 35 to monitor MSC engraftment, osteogenic differentiation, callus formation, and bone strength. Compared to ADSC culture alone, ADSC^bFGF increased bFGF expression and higher levels of bFGF and vascular endothelial growth factor (VEGF) in the culture supernatant for up to 14 days. ADSC^bFGF treatment increased GFP‐labeled MSCs at the fracture gaps and these cells were incorporated into the newly formed callus. quantitative reverse transcription polymerase chain reaction (qRT‐PCR) from the callus revealed a 2‐ to 12‐fold increase in the expression of genes associated with nervous system regeneration, angiogenesis, and matrix formation. Compared to the control, ADSC^bFGF treatment increased VEGF expression at the periosteal region of the callus, remodeling of collagen into mineralized callus and bone strength. In summary, MSC^bFGF accelerated fracture healing by increasing the production of growth factors that stimulated angiogenesis and differentiation of MSCs to osteoblasts that formed new bone and accelerated fracture repair. This novel treatment may reduce the time required for fracture healing. Stem Cells Translational Medicine2017;6:1880–1893

Functional efficacy of human recombinant FGF-2s tagged with (His)6 and (His-Asn)6 at the N- and C-termini in human gingival fibroblast and periodontal ligament-derived cells

Fibroblast growth factor (FGF) is a multifunctional growth factor that induces cell proliferation, survival, migration, and differentiation in various cell types and tissues. With these biological functions, FGF-2 has been evaluated for clinical use in the regeneration of damaged tissues. The expression of hFGF-2 in Escherichia coli and a purification system using the immobilized metal affinity chromatography (IMAC) is well established to generate a continuous supply of FGF-2. Although hexa-histidine tag (H₆) is commonly used for IMAC purification, hexa-histidine-asparagine tag (HN₆) is also efficient for purification as it is easily exposed on the surface of the protein. In this study, four different tagging constructs of hFGF-2 based on tag positions and types (H₆-FGF2, FGF2-H₆, HN₆-FGF2, and FGF2-HN₆) were designed and expressed under the inducible T7 expression system in E. coli. The experimental conditions of expression and purification of each recombinant protein were optimized. The effective dosages of the recombinant proteins were determined based on the increase of cell proliferation in human gingival fibroblast. ED50s of H₆-FGF2, FGF2-H₆, HN₆-FGF2, and FGF2-HN₆ were determined (4.42 ng/ml, 3.55 ng/ml, 3.54 ng/ml, and 4.14 ng/ml, respectively) and found to be comparable to commercial FGF-2 (3.67 ng/ml). All the recombinant hFGF-2s inhibit the osteogenic induction and mineralization in human periodontal ligament-derived cells. Our data suggested that biological activities of the recombinant hFGF-2 are irrelevant to types and positions of tags, but may have an influence on the expression efficiency and solubility.

Basic Fibroblast Growth Factor Regulates Gene and Protein Expression Related to Proliferation, Differentiation, and Matrix Production of Human Dental Pulp Cells

INTRODUCTION

Basic fibroblast growth factor (bFGF) plays differential effects on the proliferation, differentiation, and extracellular matrix turnover in various tissues. However, limited information is known about the effect of bFGF on dental pulp cells. The purposes of this study were to investigate whether bFGF influences the cell differentiation and extracellular matrix turnover of human dental pulp cells (HDPCs) and the related gene and protein expression as well as the role of the mitogen-activated protein kinase (MEK)/extracellular-signal regulated kinase (ERK) signaling pathway. The expression of fibroblast growth factor receptors (FGFRs) in HDPCs was also studied.

METHODS

The expression of FGFR1 and FGFR2 in HDPCs was investigated by reverse-transcription polymerase chain reaction. HDPCs were treated with different concentrations of bFGF. Cell proliferation was evaluated using the 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Cell differentiation was evaluated using alkaline phosphatase (ALP) staining. Changes in messenger expression of cyclin B1 and tissue inhibitor of metalloproteinase (TIMP) 1 were determined by reverse-transcription polymerase chain reaction. Changes in protein expression of cdc2, TIMP-1, TIMP-2, and collagen I were determined by Western blotting. U0126 was used to clarify the role of MEK/ERK signaling.

RESULTS

HDPCs expressed both FGFR1 and FGFR2. Cell viability was stimulated by 50-250 ng/mL bFGF. The expression and enzyme activities of ALP were inhibited by 10-500 ng/mL bFGF. At similar concentrations, bFGF stimulates cdc2, cyclin B1, and TIMP-1 messenger RNA and protein expression. bFGF showed little effect on TIMP-2 and partly inhibited collagen I expression of pulp cells. U0126 (a MEK/ERK inhibitor) attenuated the bFGF-induced increase of cyclin B1, cdc2, and TIMP-1.

CONCLUSIONS

bFGF may be involved in pulpal repair and regeneration by activation of FGFRs to regulate cell growth; stimulate cdc2, cyclin B1, and TIMP-1 expression; and inhibit ALP. These events are partly associated with MEK/ERK signaling.

Tri-Layered Nanocomposite Hydrogel Scaffold for the Concurrent Regeneration of Cementum, Periodontal Ligament, and Alveolar Bone

A tri-layered scaffolding approach is adopted for the complete and concurrent regeneration of hard tissues-cementum and alveolar bone-and soft tissue-the periodontal ligament (PDL)-at a periodontal defect site. The porous tri-layered nanocomposite hydrogel scaffold is composed of chitin-poly(lactic-co-glycolic acid) (PLGA)/nanobioactive glass ceramic (nBGC)/cementum protein 1 as the cementum layer, chitin-PLGA/fibroblast growth factor 2 as the PDL layer, and chitin-PLGA/nBGC/platelet-rich plasma derived growth factors as the alveolar bone layer. The tri-layered nanocomposite hydrogel scaffold is cytocompatible and favored cementogenic, fibrogenic, and osteogenic differentiation of human dental follicle stem cells. In vivo, tri-layered nanocomposite hydrogel scaffold with/without growth factors is implanted into rabbit maxillary periodontal defects and compared with the controls at 1 and 3 months postoperatively. The tri-layered nanocomposite hydrogel scaffold with growth factors demonstrates complete defect closure and healing with new cancellous-like tissue formation on microcomputed tomography analysis. Histological and immunohistochemical analyses further confirm the formation of new cementum, fibrous PDL, and alveolar bone with well-defined bony trabeculae in comparison to the other three groups. In conclusion, the tri-layered nanocomposite hydrogel scaffold with growth factors can serve as an alternative regenerative approach to achieve simultaneous and complete periodontal regeneration.

Evaluation of Recombinant Human FGF-2 and PDGF-BB in Periodontal Regeneration: A Systematic Review and Meta-Analysis

The prognosis for successful treatment of periodontal diseases is generally poor. Current therapeutic strategies often fail to regenerate infected periodontium. Recently an alternative strategy has been developed that combines conventional treatment with the application of recombinant human growth factors (rhGFs). But ambiguities in existed studies on the clinical efficacy of rhGFs do not permit either the identification of the specific growth factors effective for therapeutic interventions or the optimal concentration of them. Neither is it known whether the same rhGF can stimulate regeneration of both soft tissue and bone, or whether different patient populations call for differential use of the growth factors. In order to explore these issues, a meta-analysis was carried out. Particular attention was given to the therapeutic impact of fibroblast growth factor 2(FGF-2) and platelet derived growth factor BB (PDGF-BB). Our findings indicate that 0.3% rhFGF-2 and 0.3 mg/ml rhPDGF-BB show a greater capacity for periodontal regeneration than other concentrations and superiority to control groups with statistical significance. In the case of patients suffering only from gingival recession, however, the application of rhPDGF-BB produces no significant regenerative advantage. The findings of this study can potentially endow clinicians with guidelines for the appropriate application of these two rhGFs.

Effects of diode laser irradiation and fibroblast growth factor on periodontal healing of replanted teeth after extended extra-oral dry time

AIM

The search for effective protocols to reduce the incidence of root resorption and allow periodontal ligament repair is still challenging, given the unpredictable outcome of late tooth replantation. The aim of this study was to assess the effects of both high-power diode laser irradiation (DL) and basic fibroblast growth factor (FGF) on the periodontal healing of replanted teeth after extended extra-oral dry time.

METHODS

Maxillary incisors of 50 male rats were extracted and assigned to three experimental and two control groups (n = 10). DL: root surfaces treated with DL (810 nm, continuous mode, 1.0 W, 30 s), FGF: topical application of FGF gel to the root surface and in the alveolar wound, DL + FGF: DL and topical application of FGF gel, C+: no treatment after extraction and immediate replantation and C-: no treatment after extraction and replantation after 60 min. In the experimental groups, the specimens were kept dry for 60 min, the pulps were removed and the canals were filled with calcium hydroxide paste prior to tooth replantation. The animals were euthanized after 60 days. The specimens were processed for radiographic, histological and immunohistochemical analyses.

RESULTS

The radiographic analysis showed fewer resorptive areas in DL + FGF (P < 0.05). The histological and immunohistochemical analyses showed that the DL group had lower mean values of ankylosis, replacement and inflammatory resorption when compared to C-, not differing statistically from C+. DL + FGF produced significantly more collagen fibers (type I and type III) than C-, not differing from C+ in the case of type I fibers (P < 0.05).

CONCLUSIONS

DL, with or without FGF, reduced the occurrence of external root resorption and ankylosis. Periodontal healing was favored and some fiber reinsertion occurred only when FGF was used.

Regulation of PLAP-1 Expression in Periodontal Ligament Cells

Periodontal-ligament-associated protein-1 ( PLAP-1) is preferentially expressed in the periodontal ligament (PDL) and encodes a novel small leucine-rich repeat proteoglycan protein. PLAP-1 expression was induced during the course of cytodifferentiation of PDL cells into mineralized-tissue-forming cells in vitro, suggesting the possible involvement of PLAP-1 in the mineralization process of PDL cells. In this study, we hypothesized that PLAP-1 expression is regulated by mineralization-related cytokines in PDL cells. PLAP-1 expression was clearly down-regulated when the cytodifferentiation of PDL cells was reversibly inhibited by fibroblast growth factor-2 (FGF-2). In contrast, bone morphogenetic protein-2 (BMP-2) enhanced PLAP-1 expression. Up-regulation of PLAP-1 expression by BMP-2 was confirmed at the protein level when PDL cells were immunostained with anti-PLAP-1 polyclonal antibody. These results revealed the cytokine-mediated regulatory mechanisms of PLAP-1 expression and suggested that PLAP-1 expression may be associated with the process of cytodifferentiation of PDL cells.

Collagen Hydrogel Scaffold and Fibroblast Growth Factor-2 Accelerate Periodontal Healing of Class II Furcation Defects in Dog

OBJECTIVE

Collagen hydrogel scaffold exhibits bio-safe properties and facilitates periodontal wound healing. However, regenerated tissue volume is insufficient. Fibroblast growth factor-2 (FGF2) up-regulates cell behaviors and subsequent wound healing. We evaluated whether periodontal wound healing is promoted by application of collagen hydrogel scaffold in combination with FGF2 in furcation defects in beagle dogs.

METHODS

Collagen hydrogel was fabricated from bovine type I collagen with an ascorbate-copper ion cross-linking system. Collagen hydrogel was mingled with FGF2 and injected into sponge-form collagen. Subsequently, FGF2 (50 µg)/collagen hydrogel scaffold and collagen hydrogel scaffold alone were implanted into class II furcation defects in dogs. In addition, no implantation was performed as a control. Histometric parameters were assessed at 10 days and 4 weeks after surgery.

RESULT

FGF2 application to scaffold promoted considerable cell and tissue ingrowth containing numerous cells and blood vessel-like structure at day 10. At 4 weeks, reconstruction of alveolar bone was stimulated by implantation of scaffold loaded with FGF2. Furthermore, periodontal attachment, consisting of cementum-like tissue, periodontal ligament-like tissue and Sharpey's fibers, was also repaired, indicating that FGF2-loaded scaffold guided self-assembly and then re-established the function of periodontal organs. Aberrant healing, such as ankylosis and root resorption, was not observed.

CONCLUSION

FGF2-loaded collagen hydrogel scaffold possessed excellent biocompatibility and strongly promoted periodontal tissue engineering, including periodontal attachment re-organization.

Long-term Observation of Regenerated Periodontium Induced by FGF-2 in the Beagle Dog 2-Wall Periodontal Defect Model

The long-term stability and qualitative characteristics of periodontium regenerated by FGF-2 treatment were compared with normal physiological healing tissue controls in a Beagle dog 2-wall periodontal defect model 13 months after treatment by assessing tissue histology and three-dimensional microstructure using micro-computed tomography (μCT). After FGF-2 (0.3%) or vehicle treatment at the defect sites, serial changes in the bone mineral content (BMC) were observed using periodic X-ray imaging. Tissues were harvested at 13 months, evaluated histomorphometrically, and the cortical bone volume and trabecular bone structure of the newly formed bone were analyzed using μCT. FGF-2 significantly increased the BMC of the defect area at 2 months compared with that of the control group, and this difference was unchanged through 13 months. The cortical bone volume was significantly increased by FGF-2, but there was no difference between the groups in trabecular bone structure. Bone maturation was occurring in both groups because of the lower cortical volume and denser trabecular bone than what is found in intact bone. FGF-2 also increased the area of newly formed bone as assessed histomorphometrically, but the ratios of trabecular bone in the defect area were similar between the control and FGF-2 groups. These results suggest that FGF-2 stimulates neogenesis of alveolar bone that is of similar quality to that of the control group. The lengths of the regenerated periodontal ligament and cementum, measured as the distance from the defect bottom to the apical end of the gingival epithelium, and height and area of the newly formed bone in the FGF-2 group were larger than those in the control group. The present study demonstrated that, within the limitation of artificial periodontal defect model, the periodontal tissue regenerated by FGF-2 was maintained for 13 months after treatment and was qualitatively equivalent to that generated through the physiological healing process.

Emerging regenerative approaches for periodontal reconstruction: a systematic review from the AAP Regeneration Workshop

More than 30 years have passed since the first successful application of regenerative therapy for treatment of periodontal diseases. Despite being feasible, periodontal regeneration still faces numerous challenges, and complete restoration of structure and function of the diseased periodontium is often considered an unpredictable task. This review highlights developing basic science and technologies for potential application to achieve reconstruction of the periodontium. A comprehensive search of the electronic bibliographic database PubMed was conducted to identify different emerging therapeutic approaches reported to influence either biologic pathways and/or tissues involved in periodontal regeneration. Each citation was assessed based on its abstract, and the full text of potentially eligible reports was retrieved. Based on the review of the full papers, their suitability for inclusion in this report was determined. In principle, only reports from scientifically well-designed studies that presented preclinical in vivo (animal studies) or clinical (human studies) evidence for successful periodontal regeneration were included. Hence, in vitro studies, namely those conducted in laboratories without any live animals, were excluded. In case of especially recent and relevant reviews with a narrow focus on specific regenerative approaches, they were identified as such, and thereby the option of referring to them to summarize the status of a specific approach, in addition to or instead of listing each separately, was preserved. Admittedly, the presence of subjectivity in the selection of studies to include in this overview cannot be excluded. However, it is believed that the contemporary approaches described in this review collectively represent the current efforts that have reported preclinical or clinical methods to successfully enhance regeneration of the periodontium. Today's challenges facing periodontal regenerative therapy continue to stimulate important research and clinical development, which, in turn, shapes the current concept of periodontal tissue engineering. Emerging technologies--such as stem cell therapy, bone anabolic agents, genetic approaches, and nanomaterials--also offer unique opportunities to enhance the predictability of current regenerative surgical approaches and inspire development of novel treatment strategies.

Randomized Placebo-Controlled and Controlled Non-Inferiority Phase III Trials Comparing Trafermin, a Recombinant Human Fibroblast Growth Factor 2, and Enamel Matrix Derivative in Periodontal Regeneration in Intrabony Defects

We investigated the efficacy, safety, and clinical significance of trafermin, a recombinant human fibroblast growth factor (rhFGF)-2, for periodontal regeneration in intrabony defects in Phase III trials. Study A, a multicenter, randomized, double-blind, placebo-controlled study, was conducted at 24 centers. Patients with periodontitis with 4-mm and 3-mm or deeper probing pocket depth and intrabony defects, respectively, were included. A total of 328 patients were randomly assigned (2:1) to receive 0.3% rhFGF-2 or placebo, and 323 patients received the assigned investigational drug during flap surgery. One of the co-primary endpoints, the percentage of bone fill at 36 weeks after drug administration, was significantly greater in the rhFGF-2 group at 37.131% (95% confidence interval [CI], 32.7502 to 41.5123; n = 208) than it was in the placebo group at 21.579% (95% CI, 16.3571 to 26.8011; n = 100; p < 0.001). The other endpoint, the clinical attachment level regained at 36 weeks, was not significantly different between groups. Study B, a multicenter, randomized, blinded (patients and evaluators of radiographs), and active-controlled study was conducted at 15 centers to clarify the clinical significance of rhFGF-2. Patients with 6-mm and 4-mm or deeper probing pocket depth and intrabony defects, respectively, were included. A total of 274 patients were randomly assigned (5:5:2) to receive rhFGF-2, enamel matrix derivative (EMD), or flap surgery alone. A total of 267 patients received the assigned treatment during flap surgery. The primary endpoint, the linear alveolar bone growth at 36 weeks, was 1.927 mm (95% CI, 1.6615 to 2.1920; n = 108) in the rhFGF-2 group and 1.359 mm (95% CI, 1.0683 to 1.6495; n = 109) in the EMD group, showing non-inferiority (a prespecified margin of 0.3 mm) and superiority of rhFGF-2 to EMD. Safety problems were not identified in either study. Therefore, trafermin is an effective and safe treatment for periodontal regeneration in intrabony defect, and its efficacy was superior in rhFGF-2 compared to EMD treatments.

Periodontal regeneration with 0.3% basic fibroblast growth factor (FGF-2) for a patient with aggressive periodontitis: a case report

This case report describes the clinical efficacy of treatment with basic fibroblast growth factor (FGF-2) for periodontal regeneration. A patient with aggressive periodontitis participated in a clinical trial involving administration of 0.3% FGF-2 in comparison with a placebo control. To evaluate the efficacy of FGF-2, standardized radiographs were taken before surgery and at 12, 24, and 36 weeks after FGF-2 treatment. The rate of increase in alveolar bone height was 86.9% at 36 weeks. The 6-year postoperative radiograph showed significant development of alveolar bone in comparison with the first visit. FGF-2 treatment may be effective for periodontal regeneration in cases of aggressive periodontitis. (J Oral Sci 58, 137-140, 2016).

Cytokines during periodontal wound healing: potential application for new therapeutic approach

Regeneration of periodontal tissues is one of the main goals of periodontal therapy. However, current treatment, including surgical approach, use of membrane to allow maturation of all periodontal tissues, or use of enamel matrix derivatives, presents limitations in their indications and outcomes leading to the development of new tissue engineering strategies. Several cytokines are considered as key molecules during periodontal destruction process. However, their role during each phase of periodontal wound healing remains unclear. Control and modulation of the inflammatory response and especially, release of cytokines or activation/inhibition in a time- and spatial-controlled manner may be a potential perspective for periodontal tissue engineering. The aim of this review was to summarize the specific role of several cytokines during periodontal wound healing and the potential therapeutic interest of inflammatory modulation for periodontal regeneration especially related to the expression sequence of cytokines.

FGF-2 promotes initial osseointegration and enhances stability of implants with low primary stability

OBJECTIVES

The aim of this study was to examine the effect of basic fibroblast growth factor (FGF-2) on osseointegration of dental implants with low primary stability in a beagle dog model.

MATERIALS AND METHODS

Customized titanium implants that were designed to have low contact with the existing bone were installed into the edentulous mandible of beagle dogs. To degrade the primary stability of the implants, the diameters of the bone sockets exceeded the implant diameters. FGF-2 (0.3%) plus vehicle (hydroxypropyl cellulose) or vehicle alone was topically applied to the sockets in the FGF-2 and control groups, respectively. In Study 1, the new bone area and length of new bone-to-implant contact (BIC) were evaluated at 4, 8, and 12 weeks after installation using histomorphometry and scanning electron microscopy. In Study 2, the implant stability quotient (ISQ) values were sequentially measured for 16 weeks using an Osstell system.

RESULTS

The histomorphometric analysis revealed that the new bone area and length of BIC in the FGF-2 group were significantly larger than those in the control group at 4 weeks. Electron microscopic observation showed intimate contact between the mature lamellar bone and the implant surfaces, osseointegration, in both groups. The ISQ values in the FGF-2 group were significantly increased from 6 to 16 weeks compared with those in the control group.

CONCLUSIONS

Taken together, our study demonstrates that FGF-2 promoted new bone formation around the dental implants and subsequent osseointegration, resulting in promotion of stability of implants with low primary stability.

A Randomized Clinical Trial Evaluating rh-FGF-2/β-TCP in Periodontal Defects

Biological mediators have been used to enhance periodontal regeneration. The aim of this prospective randomized controlled study was to evaluate the safety and effectiveness of 3 doses of fibroblast growth factor 2 (FGF-2) when combined with a β-tricalcium phosphate (β-TCP) scaffold carrier placed in vertical infrabony periodontal defects in adult patients. In this double-blinded, dose-verification, externally monitored clinical study, 88 patients who required surgical intervention to treat a qualifying infrabony periodontal defect were randomized to 1 of 4 treatment groups—β-TCP alone (control) and 0.1% recombinant human FGF-2 (rh-FGF-2), 0.3% rh-FGF-2, and 0.4% rh-FGF-2 with β-TCP—following scaling and root planing of the tooth prior to a surgical appointment. Flap surgery was performed with EDTA conditioning of the root prior to device implantation. There were no statistically significant differences in patient demographics and baseline characteristics among the 4 treatment groups. When a composite outcome of gain in clinical attachment of 1.5 mm was used with a linear bone growth of 2.5 mm, a dose response pattern detected a plateau in the 0.3% and 0.4% rh-FGF-2/β-TCP groups with significant improvements over control and 0.1% rh-FGF-2/β-TCP groups. The success rate at 6 mo was 71% in the 2 higher-concentration groups, as compared with 45% in the control and lowest treatment groups. Percentage bone fill in the 2 higher-concentration groups was 75% and 71%, compared with 63% and 61% in the control and lowest treatment group. No increases in specific antibody to rh-FGF-2 were detected, and no serious adverse events related to the products were reported. The results from this multicenter trial demonstrated that the treatment of infrabony vertical periodontal defects can be enhanced with the addition of rh-FGF-2/β-TCP ( ClinicalTrials.gov NCT01728844).