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

Growth factors and growth factor gene therapies for treating chronic wounds

Chronic wounds are an unmet clinical need affecting millions of patients globally, and current standards of care fail to consistently promote complete wound closure and prevent recurrence. Disruptions in growth factor signaling, a hallmark of chronic wounds, have led researchers to pursue growth factor therapies as potential supplements to standards of care. Initial studies delivering growth factors in protein form showed promise, with a few formulations reaching clinical trials and one obtaining clinical approval. However, protein-form growth factors are limited by instability and off-target effects. Gene therapy offers an alternative approach to deliver growth factors to the chronic wound environment, but safety concerns surrounding gene therapy as well as efficacy challenges in the gene delivery process have prevented clinical translation. Current growth factor delivery and gene therapy approaches have primarily used single growth factor formulations, but recent efforts have aimed to develop multi-growth factor approaches that are better suited to address growth factor insufficiencies in the chronic wound environment, and these strategies have demonstrated improved efficacy in preclinical studies. This review provides an overview of chronic wound healing, emphasizing the need and potential for growth factor therapies. It includes a summary of current standards of care, recent advances in growth factor, cell-based, and gene therapy approaches, and future perspectives for multi-growth factor therapeutics.

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.

Predictive factors of periodontal regeneration outcomes using rhFGF-2: A case-control study

OBJECTIVE

This study aimed to investigate the factors influencing the clinical outcomes of regenerative therapy using recombinant human fibroblast growth factor-2 (rhFGF-2).

BACKGROUND

rhFGF-2 promotes periodontal regeneration, and identifying the factors influencing this regeneration is important for optimizing the effectiveness of rhFGF-2.

METHODS AND MATERIALS

This study used a hospital information-integrated database to identify patients who underwent periodontal regenerative therapy with rhFGF-2. Factors included age, smoking status, diabetes mellitus (DM), periodontal inflamed surface area (PISA) at the initial visit, whether the most posterior tooth was involved or not, and preoperative radiological bone defect angle. Periodontal regenerative therapy outcomes were defined as good if radiographic bone fill ≥35% or periodontal pocket closure at 9-15 months after surgery. Bone fill rate (%) and periodontal pocket depth (mm) were also used as outcome measures. Factors were evaluated by simple regression analysis, and then the association between factors and the outcomes was determined by multivariate analysis.

RESULTS

PISA and age at the first visit did not significantly influence the success or failure of bone fill rate byrhFGF-2. However, DM, radiographic bone defect angle, and the most posterior tooth significantly influenced the regenerative effect (success/failure in bone fill) of rhFGF-2. The most posterior tooth was significantly associated with bone fill rate by rhFGF-2. Examination of the association between pocket closure and factors shows that the most posterior tooth significantly influenced. The most posterior tooth and preoperative PPD were significantly associated with pocket reduction depth. For the most posterior tooth, a significantly higher bone regeneration rate (p < .05) was observed with a combination of autologous bone graft and rhFGF-2 than with rhFGF-2 alone, and the effect was significant in multivariate analysis.

CONCLUSIONS

The radiographic bone defect angle, the involvement of most posterior teeth, and the presence of DM influenced the effectiveness of rhFGF-2 in periodontal regeneration. However, PISA values and age at the initial visit had no significant effect.

Biological processes and factors involved in soft and hard tissue healing

Wound healing is a complex and iterative process involving myriad cellular and biologic processes that are highly regulated to allow satisfactory repair and regeneration of damaged tissues. This review is intended to be an introductory chapter in a volume focusing on the use of platelet concentrates for tissue regeneration. In order to fully appreciate the clinical utility of these preparations, a sound understanding of the processes and factors involved in soft and hard tissue healing. This encompasses an appreciation of the cellular and biological mediators of both soft and hard tissues in general as well as specific consideration of the periodontal tissues. In light of good advances in this basic knowledge, there have been improvements in clinical strategies and therapeutic management of wound repair and regeneration. The use of platelet concentrates for tissue regeneration offers one such strategy and is based on the principles of cellular and biologic principles of wound repair discussed in this review.

The effect of fibroblast growth factor-2 on the outcomes of tooth replantation: A systematic review of animal studies

Background/Aim: The ideal treatment of tooth avulsion is replantation. However, replanting teeth may lead to root resorption. Fibroblast growth factor-2 (FGF-2) is a cytokine that plays an important role in wound repair and tissue regeneration. Recently, FGF-2 has been studied a potential regenerative agent to prevent root resorption and ankylosis. The aim of this review is to analyze and summarize the currently available literature focusing on using FGF-2 based regenerative modalities to improve the outcomes of tooth replantation. Materials and Methods: An electronic search was conducted via PubMed/Medline, Google Scholar and ISI Web of Knowledge, using the Medical Subject Headings (MeSH) terms "Basic fibroblast growth factor," "Fibroblast growth factor-2," "tooth replantation," and "replantation" for studies published between January 2001 and June 2021. Data was extracted and quality assessment was carried using the ARRIVE guidelines. Results: Nine animal studies were included in this review. In six studies, FGF-2 had a favorable effect on the tissue regeneration around roots of replanted teeth when compared to other treatment groups. However, quality assessment of the studies revealed many sources of bias and deficiencies in the studies. Conclusions: Within the limitations of this study, it may be concluded that FGF-2 may improve the outcomes of delayed replantation of avulsed teeth. However, more long-term animal studies, with improved experimental designs, and clinical trials are required to determine the clinical potential of the growth factor in improving the outcomes of delayed tooth replantation.

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.

Periodontal Regenerative Therapy with Recombinant Human Fibroblast Growth Factor (rhFGF) -2 for Stage III Grade C Periodontitis: A Case Report with 6-month Follow-up

This report describes a case of generalized chronic periodontitis requiring periodontal regenerative therapy. The patient was a 56-year-old woman visiting the Tokyo Dental College Suidobashi Hospital with the chief complaint of swelling in the maxillary right gingiva. An initial examination revealed 34.0% of sites with a probing depth (PD) of ≥4 mm. The prevalence of sites with bleeding on probing was 32.7%. The plaque control record (PCR) score was 65.7%. Radiographic examination revealed angular bone resorption at #18 and 48. Horizontal absorption was also observed in other areas. The percent bone loss/age at #48 was 1.07. A clinical diagnosis of generalized chronic periodontitis (Stage III, Grade C) was made. Based on the clinical diagnosis of severe chronic periodontitis, initial periodontal therapy was performed. An improvement was observed in periodontal conditions at re-evaluation. The PCR score was 16.7%. Periodontal surgery was performed for teeth with a residual PD of ≥4 mm. Periodontal regenerative therapy using rhFGF-2 were performed on intrabony defects in #18 and 48. Open flap debridement was performed on #16, 26, and 27. Following evaluation, oral function was restored using all-ceramic crowns (#46). At 6 months postoperatively, the patient was transitioned to supportive periodontal therapy (SPT). During the 6-month SPT, stable periodontal conditions that facilitated a favourable level of plaque control were maintained.

Comparison of early wound healing using modified papilla preservation technique between enamel matrix derivative and recombinant human fibroblast growth factor

PURPOSE

Enamel matrix derivative (EMD) has demonstrated beneficial effects on wound healing following surgery. However, the effects of recombinant human fibroblast growth factor 2 (rhFGF-2) in periodontal regeneration therapy have not been extensively studied. This retrospective study was conducted to compare the wound healing outcomes of the modified papilla preservation technique (mPPT) between EMD and rhFGF-2 therapies.

METHODS

A total of 79 sites were evaluated for early wound healing using the modified early wound healing index (mEHI), which included 6 items: incision, fibrin clotting, step, redness, swelling, and dehiscence. A numeric analog scale, along with postoperative images of the 6 mEHI items, was established and used for the evaluations. The inter-rater reliability of the mEHI was assessed via intraclass correlation coefficients (ICCs). After adjusting for factors influencing the mPPT, the differences in mEHI scores between the EMD and rhFGF-2 groups were statistically analyzed. Additionally, radiographic bone fill (RBF) was evaluated 6 months after surgery.

RESULTS

The ICC of the mEHI was 0.575. The mEHI, redness score, and dehiscence scores were significantly higher in the rhFGF-2 group (n=33) than in the EMD group (n=46). Similar results were observed in the subgroup of patients aged 50 years or older, but not in those younger than 50 years. In the subgroup with non-contained bone defects, related results were noted, but not in the subgroup with contained bone defects. However, early wound healing did not correlate with RBF at 6 months after surgery.

CONCLUSIONS

Within the limitations of this study, the findings suggest that early wound healing following the use of mPPT with rhFGF-2 is somewhat superior to that observed after mPPT with EMD. However, mEHI should be improved for use as a predictive tool for early wound healing and to reflect clinical outcomes after surgery.

The use of basic fibroblast growth factor to improve vocal function: A systematic review and meta-analysis

OBJECTIVES

This systematic review and meta-analysis examines if intralaryngeal injection of basic fibroblast growth factor 2 (FGF2) can improve voice outcomes in those with vocal disability.

DESIGN

A Systematic review of original human studies reporting voice outcomes following intra-laryngeal injection of basic fibroblast growth factor 2 in those with vocal dysfunction. Databases searched were Medline (1946-July 2022), Embase (1947-July 2022), Cochrane database and Google Scholar.

SETTING

Secondary or tertiary care centres that undertook the management of voice pathology Hospital.

PARTICIPANTS

Inclusion criteria were original human studies reporting voice outcome measurements following intralaryngeal injection of FGF2 to treat vocal fold atrophy, vocal fold scarring, vocal fold sulcus or vocal fold palsy. Articles not written in English, studies that did not include human subjects and studies where voice outcome measures were not recorded before and after FGF2 injection were excluded from the review.

MAIN OUTCOME MEASURES

The primary outcome measure was maximum phonation time. Secondary outcome measures included acoustic analysis, glottic closure, mucosal wave formation, voice handicap index and GRBAS scale.

RESULTS

Fourteen articles were included out of a search of 1023 and one article was included from scanning reference lists. All studies had a single arm design without control groups. Conditions treated were vocal fold atrophy (n = 186), vocal cord paralysis (n = 74), vocal fold fibrosis (n = 74) and vocal fold sulcus (n = 56). A meta-analysis of six articles reporting on the use of FGF2 in patients with vocal fold atrophy showed a significant increase of mean maximum phonation time of 5.2 s (95% CI: 3.4-7.0) at 3-6 months following injection. A significant improvement in maximum phonation time, voice handicap index and glottic closure was found following injection in most studies assessed. No major adverse events were reported following injection.

CONCLUSIONS

To date, intralaryngeal injection of basic FGF2 appears to be safe and it may be able to improve voice outcomes in those with vocal dysfunction, especially vocal fold atrophy. Randomised controlled trials are needed to further evaluate efficacy and support the wider use of this therapy.

Roles of extracellular adenosine triphosphate on the functions of periodontal ligament cells

OBJECTIVE

Adenosine triphosphate (ATP) is an essential nucleotide that is normally present in both intracellular and extracellular compartments. Extracellular ATP (eATP) has a pivotal role in both physiological and pathological processes of periodontal ligament tissues. Here, this review aimed to explore the various functions of eATP that are involved in the control of behaviours and functions of periodontal ligament cells.

METHODS

To identify the included publications for review, the articles were searched in PubMed (MEDLINE) and SCOPUS with the keywords of adenosine triphosphate and periodontal ligament cells. Thirteen publications were used as the main publications for discussion in the present review.

RESULTS

eATP has been implicated as a potent stimulator for inflammation initiation in periodontal tissues. It also plays a role in proliferation, differentiation, remodelling, and immunosuppressive functions of periodontal ligament cells. Yet, eATP has diverse functions in regulating periodontal tissue homeostasis and regeneration.

CONCLUSION

eATP may provide a new prospect for periodontal tissue healing as well as treatment of periodontal disease especially periodontitis. It may be utilized as a useful therapeutic tool for future periodontal regeneration therapy.

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.

Sclerostin deficiency effectively promotes bone morphogenetic protein-2-induced ectopic bone formation

BACKGROUND AND OBJECTIVE

Severe periodontitis causes alveolar bone resorption, resulting in tooth loss. Developments of tissue regeneration therapy that can restore alveolar bone mass are desired for periodontal disease. The application of bone morphogenetic protein-2 (BMP-2) has been attempted for bone fractures and severe alveolar bone loss. BMP-2 reportedly induces sclerostin expression, an inhibitor of Wnt signals, that attenuates bone acquisition. However, the effect of sclerostin-deficiency on BMP-2-induced bone regeneration has not been fully elucidated. We investigated BMP-2-induced ectopic bones in Sost-knockout (KO) mice.

METHODS

rhBMP-2 were implanted into the thighs of C57BL/6 (WT) and Sost-KO male mice at 8 weeks of age. The BMP-2-induced ectopic bones in these mice were examined on days 14 and 28 after implantation.

RESULTS

Immunohistochemical and quantitative RT-PCR analyses showed that BMP-2-induced ectopic bones expressed sclerostin in osteocytes on days 14 and 28 after implantation in Sost-Green reporter mice. Micro-computed tomography analysis revealed that BMP-2-induced ectopic bones in Sost-KO mice showed a significant increased relative bone volume and bone mineral density (WT = 468 mg/cm³ , Sost-KO = 602 mg/cm³ ) compared with those in WT mice on day 14 after implantation. BMP-2-induced ectopic bones in Sost-KO mice showed an increased horizontal cross-sectional bone area on day 28 after implantation. Immunohistochemical staining showed that BMP-2-induced ectopic bones in Sost-KO mice had an increased number of osteoblasts with osterix-positive nuclei compared with those in WT mice on days 14 and 28 after implantation.

CONCLUSION

Sclerostin deficiency increased bone mineral density in BMP-2-induced ectopic bones.

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.

Treatment of Stage III Grade C Periodontitis with Periodontal Regenerative Therapy including Guided Tissue Regeneration (GTR) and Recombinant Human Fibroblast Growth Factor (rhFGF)-2: A Case Report

This report describes a case of periodontitis treated with periodontal surgery including guided tissue regeneration (GTR) and recombinant human fibroblast growth factor (rhFGF)-2. The patient was a 54-year-old woman who visited the Tokyo Dental College Suidobashi Hospital with the chief complaint of swelling in the maxillary right gingiva. An initial examination revealed 30.4% of sites with a probing depth (PD) of ≥4 mm. The prevalence of sites with bleeding on probing was 57.7%. The plaque control record (PCR) score was 66.1%. Radiographic examination revealed vertical bone defects in the molar region. Based on these findings, the clinical diagnosis was generalized chronic periodontitis (Stage III, Grade C). Initial periodontal therapy yielded an improvement in periodontal conditions, with the PCR score reducing to 13.8%. Periodontal surgery was performed for teeth with a residual PD ≥4 mm. Guided tissue regeneration was performed on #37 and 47. A series of periodontal regenerative treatments comprising application of rhFGF-2 was performed on angular bone defects in #14, 15, 25, and 27. Open flap debridement was performed on #16, 17, 26, 36, and 46. Following evaluation, oral function was restored by placing all-ceramic crowns on #21 and 26. The patient was then placed on supportive periodontal therapy. In the present case of generalized chronic periodontitis, periodontal regenerative therapy with GTR and rhFGF-2 yielded stable periodontal conditions.

The efficiency of the regeneration of periodontal intrabony defects in East Asians: A systematic review and pooled analysis

This article aimed to assess the efficacy of periodontal regenerative therapy (PRT) for treating periodontal intrabony defects in East Asians. The systematic review was performed according to the PRISMA guidelines. Literature searches on the PubMed and national medical journal databases, and representative clinical journals of the East Asians were performed on July 31, 2018. Randomized controlled trials, prospective case-control studies, retrospective analyses, and case series receiving regenerative procedures, including barrier membrane (BM) and enamel matrix derivative (EMD) applications with or without bone replacement graft (BRG), with follow-up periods of 6 and 12 months were evaluated. The outcome variables were probing depth (PD) reduction and clinical attachment level (CAL) gain. Twenty studies were included, of which eight were assessed for bias risk. Compared to open flap debridement, PD reduction and CAL gain were superior in all PRTs at both follow-up time points. BM or EMD alone showed equivalent outcomes at 6 months, and CAL gain appeared greater with BM alone at 12 months. BM with BRG showed inferior CAL gain relative to BM alone, but EMD with BRG showed superior CAL gain relative to EMD alone at 12 months. In conclusion, PRT showed improved regenerative outcomes compared with OFD in East Asians, while BM application appeared less efficient than in non-East Asians. BRG supplementation provided additional clinical benefits in EMD application.

Periodontal Tissue Regeneration by Transplantation of Autologous Adipose Tissue-Derived Multi-Lineage Progenitor Cells With Carbonate Apatite

We have developed an autologous transplantation method using adipose tissue-derived multi-lineage progenitor cells (ADMPCs) as a method of periodontal tissue regeneration that can be adapted to severe periodontal disease. Our previous clinical study confirmed the safety of autologous transplantation of ADMPCs and demonstrated its usefulness in the treatment of severe periodontal disease. However, in the same clinical study, we found that the fibrin gel used as the scaffold material might have caused gingival recession and impaired tissue regeneration in some patients. Carbonate apatite has a high space-making capacity and has been approved in Japan for periodontal tissue regeneration. In this study, we selected carbonate apatite as a candidate scaffold material for ADMPCs and conducted an in vitro examination of its effect on the cellular function of ADMPCs. We further performed autologous ADMPC transplantation with carbonate apatite as the scaffold material in a model of one-wall bone defects in beagles and then analyzed the effect on periodontal tissue regeneration. The findings showed that carbonate apatite did not affect the cell morphology of ADMPCs and that it promoted proliferation. Moreover, no effect on secretor factor transcription was found. The results of the in vivo analysis confirmed the space-making capacity of carbonate apatite, and the acquisition of significant new attachment was observed in the group involving ADMPC transplantation with carbonate apatite compared with the group involving carbonate apatite application alone. Our results demonstrate the usefulness of carbonate apatite as a scaffold material for ADMPC transplantation.

Efficacy of biologics for the treatment of periodontal infrabony defects: An American Academy of Periodontology best evidence systematic review and network meta-analysis

BACKGROUND

A large variety of biomaterials, biologics and membranes have been utilized in the past 40 years for the regenerative treatment of periodontal infrabony defects. Biologic agents have progressively gained popularity among clinicians and are routinely used for periodontal regeneration. In alignment with the goals of the American Academy of Periodontology (AAP) Best Evidence Consensus (BEC) on the use of biologic mediators in contemporary clinical practice, the aim of this sytematic review was to evaluate the effect of biologic agents, specifically autogenous blood-dervied products (ABPs), enamel matrix derivative (EMD) and recombinant human platelet-derived growth factor-BB (rhPDGF-BB), on the regenerative outcomes of infrabony defects.

METHODS

A detailed systematic search was conducted to identify eligible randomized control trials (RCTs) reporting the outcomes of periodontal regenerative therapy using biologics for the treatment of infrabony defects. A frequentist mixed-modeling approach to network meta-analysis (NMA), characterized by the assessment of three individual components for the treatment of an infrabony defect (the bone graft material [BG], the biologic agent, the application of a barrier membrane) was performed to evaluate and compare the relative efficacy of the different components, on the outcomes of different therapeutic modalities of periodontal regeneration.

RESULTS

A total of 153 eligible RCTs were included, with 150 studies contributing to the NMA. The quantitative analysis showed that the addition of biologic agents to bone graft significantly improves the clinical and radiographic outcomes, as compared to BG and flap procedures alone. Barrier membranes enhanced the regenerative outcomes of BG but did not provide further benefits in combination with biologics. The type of BG (autogenous, allogeneic, xenogeneic or alloplastic) and the biologic agent (EMD, platelet-rich fibrin [PRF], platelet-rich plasma [PRP] or rhPDGF-BB) played a significant role on the final outcomes of infrabony defects. Allogeneic and xenogeneic BGs exhibited statistically significantly superior clinical gain than synthetic and autogenous BGs (p < 0.05 in all the comparisons), while rhPDGF-BB and PRF demonstrated significantly higher stability of the gingival margin (p < 0.01) and radiographic bone fill/gain (p < 0.05), together with greater, although not statistically significant, clinical attachment level gain and pocket depth reduction, than EMD and PRP. Overall, rhPDGF-BB exhibited the largest effect size for most parameters, including clinical attachment level gain, pocket depth reduction, less gingival recession and radiographic linear bone gain. Considering the relatively high number of trials presenting an unclear or high risk of bias, the strength of recommendation supporting the use of PRP was judged weak, while the recommendation for EMD, PRF and rhPDGF-BB was deemed in favor.

CONCLUSIONS

Biologics enhance the outcomes of periodontal regenerative therapy. Combination therapies involving BGs + biologics or BGs + barrier membrane demonstrated to be superior to monotherapies. The choice of the type of BG and biologic agent seems to have significant impact on the clinical and radiographic outcomes of infrabony defects.

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).

•

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

•

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

•

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

•

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.

•

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

•

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

•

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

•

Preoperative radiographic defect depth predicts postoperative bone fill.

Periodontal Regenerative Therapy Using rhFGF-2 and Deproteinized Bovine Bone Mineral versus rhFGF-2 Alone: 4-Year Extended Follow-Up of a Randomized Controlled Trial

The aim of this study was to evaluate longitudinal outcomes of recombinant human fibroblast growth factor (rhFGF)-2 plus deproteinized bovine bone mineral (DBBM) therapy in comparison with rhFGF-2 alone for treating periodontal intrabony defects. This study describes 4-year follow-up outcomes of the original randomized controlled trial. Intrabony defects in periodontitis patients were treated with rhFGF-2 (control) or rhFGF-2 plus DBBM (test). Clinical, radiographic, and patient-reported outcome (PRO) measures were used to evaluate the outcomes. Thirty-two sites were able to be followed up. At 4 years postoperatively, clinical attachment level (CAL) gains in the test and control groups were 3.5 ± 1.4 mm and 2.7 ± 1.4 mm, respectively, showing significant improvement from preoperative values but no difference between groups. Both groups showed an increase in radiographic bone fill (RBF) over time. At 4 years, the mean value for RBF in the test group (62%) was significantly greater than that in the control group (42%). In 1-2-wall defects, the test treatment yielded significantly greater RBF than the control treatment. No significant difference in PRO scores was noted between the groups. Although no significant difference in CAL gain was found between the groups at the 4-year follow-up, the combination treatment significantly enhanced RBF. Favorable clinical, radiographic outcomes, and PRO in both groups can be maintained for at least 4 years.

Next-Generation Examination, Diagnosis, and Personalized Medicine in Periodontal Disease

Periodontal disease, a major cause of tooth loss, is an infectious disease caused by bacteria with the additional aspect of being a noncommunicable disease closely related to lifestyle. Tissue destruction based on chronic inflammation is influenced by host and environmental factors. The treatment of periodontal disease varies according to the condition of each individual patient. Although guidelines provide standardized treatment, optimization is difficult because of the wide range of treatment options and variations in the ideas and skills of the treating practitioner. The new medical concepts of “precision medicine” and “personalized medicine” can provide more predictive treatment than conventional methods by stratifying patients in detail and prescribing treatment methods accordingly. This requires a new diagnostic system that integrates information on individual patient backgrounds (biomarkers, genetics, environment, and lifestyle) with conventional medical examination information. Currently, various biomarkers and other new examination indices are being investigated, and studies on periodontal disease-related genes and the complexity of oral bacteria are underway. This review discusses the possibilities and future challenges of precision periodontics and describes the new generation of laboratory methods and advanced periodontal disease treatment approaches as the basis for this new field.

Cross-linked hyaluronic acid gel with or without a collagen matrix in the treatment of class III furcation defects: A histologic and histomorphometric study in dogs

AIM

To histologically evaluate the effects of cross-linked hyaluronic acid (xHyA) with or without a collagen matrix (CM) on periodontal wound healing/regeneration in class III furcation defects in dogs.

MATERIALS AND METHODS

Class III furcation defects were surgically created in the mandibular premolars in six beagle dogs. The defects were randomly treated as follows: open flap debridement (OFD) + CM (CM), OFD + xHyA (xHyA), OFD + xHyA + CM (xHyA/CM) and OFD alone (OFD). At 10 weeks, the animals were euthanized for histological evaluation.

RESULTS

The newly formed bone areas in the xHyA (4.04 ± 1.51 mm² ) and xHyA/CM (4.32 ± 1.14 mm² ) groups were larger than those in the OFD (3.25 ± 0.81 mm² ) and CM (3.31 ± 2.26 mm² ) groups. The xHyA (6.25 ± 1.45 mm) and xHyA/CM (6.40 ± 1.35 mm) groups yielded statistically significantly (p < .05) greater formation of new connective tissue attachment (i.e., new cementum, with inserting connective tissue fibres) compared with the OFD (1.47 ± 0.85 mm) group. No significant differences were observed in any of the histomorphometric parameters between the xHyA and xHyA/CM groups. Complete furcation closure was not observed in any of the four treatment modalities.

CONCLUSIONS

Within their limits, the present results suggest that the use of xHyA with or without CM positively influences periodontal wound healing in surgically created, acute-type class III furcation defects.

Plap-1 lineage tracing and single-cell transcriptomics reveal cellular dynamics in the periodontal ligament

Periodontal tissue supports teeth in the alveolar bone socket via fibrous attachment of the periodontal ligament (PDL). The PDL contains periodontal fibroblasts and stem/progenitor cells, collectively known as PDL cells (PDLCs), on top of osteoblasts and cementoblasts on the surface of alveolar bone and cementum, respectively. However, the characteristics and lineage hierarchy of each cell type remain poorly defined. This study identified periodontal ligament associated protein-1 (Plap-1) as a PDL-specific extracellular matrix protein. We generated knock-in mice expressing CreERT2 and GFP specifically in Plap-1-positive PDLCs. Genetic lineage tracing confirmed the long-standing hypothesis that PDLCs differentiate into osteoblasts and cementoblasts. A PDL single-cell atlas defined cementoblasts and osteoblasts as Plap-1−Ibsp+Sparcl1+ and Plap-1−Ibsp+Col11a2+, respectively. Other populations, such as Nes+ mural cells, S100B+ Schwann cells, and other non-stromal cells, were also identified. RNA velocity analysis suggested that a Plap-1highLy6a+ cell population was the source of PDLCs. Lineage tracing of Plap-1+ PDLCs during periodontal injury showed periodontal tissue regeneration by PDLCs. Our study defines diverse cell populations in PDL and clarifies the role of PDLCs in periodontal tissue homeostasis and repair.

Application of Medical Imaging and 3D Printing Technology in Teaching the Handling of Novel Medicine in Periodontal Surgery

Recently, fibroblast growth factor-2 (FGF-2) agents for periodontal tissue regeneration have been increasingly applied to the treatment of periodontal disease. Our current challenge for resident dentists with little clinical experience is to enhance instruction in the handling of new medicine in addition to teaching conventional procedures in periodontal tissue regeneration. This report describes using case-specific, cost-effective three-dimensional (3D) models for dentists' lectures and periodontal surgical training.

As an educational and training aid, preoperative and postoperative cone-beam computed tomography images were superimposed to enable three-dimensional observation of postoperative bone regeneration. A three-dimensional anatomical model was fabricated based on these images. Dental laboratory materials were used to reproduce the periosteum and gum. The fabrication time per 3D model was about 2 hours and the cost per model was about $0.5. These models were used for lectures to resident dentists and periodontal surgery training, and their feedback was obtained. The resident's response to surgical training using these 3D models was generally positive.

The use of FGF-2 represents a new direction in the treatment of periodontal disease. This being new, however, means that inexperienced periodontists require training in its application and how this will affect prognosis, as this will differ from that with more conventional techniques aimed at tissue regeneration. The low-cost 3D model presented in this report can be a valuable tool to help accomplish this in teaching inexperienced dentists, such as resident dentists.

Comparison of periodontal wound healing/regeneration by recombinant human fibroblast growth factor-2 combined with β-tricalcium phosphate, carbonate apatite, or deproteinized bovine bone mineral in a canine one-wall intra-bony defect model

AIM

To evaluate periodontal wound healing/regeneration of one-wall intra-bony defects treated with recombinant human fibroblast growth factor-2 (rhFGF-2) and beta-tricalcium phosphate (β-TCP), carbonate apatite (CO₃ Ap), or deproteinized bovine bone mineral (DBBM) in dogs.

MATERIALS AND METHODS

The stability of rhFGF-2 adsorbed onto the bone substitutes was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA). One-wall intra-bony defects (5 × 5 × 5 mm) created in five adult male beagle dogs were treated with rhFGF-2 alone (rhFGF-2), rhFGF-2 with β-TCP (rhFGF-2/β-TCP), rhFGF-2 with CO₃ Ap (rhFGF-2/CO₃ Ap), or rhFGF-2 with DBBM (rhFGF-2/DBBM). Histological outcomes (e.g., linear length of new cementum adjacent to the newly formed bone with inserting collagen fibres [NA] as the primary outcome) were evaluated at 10 weeks post surgery.

RESULTS

Significantly higher amount of rhFGF-2 was adsorbed onto CO₃ Ap compared with β-TCP. Among the treatment groups, the rhFGF-2/DBBM group showed the highest amount of periodontal tissue regeneration. The rhFGF-2/DBBM group showed significantly greater formation of NA (3.22 ± 0.40 mm) compared with rhFGF-2 (1.17 ± 1.00 mm, p < .01) group. Additionally, new bone area in the rhFGF-2/DBBM group (9.78 ± 2.30 mm² ) was significantly higher than that in the rhFGF-2 (5.08 ± 1.26 mm² , p < .01), rhFGF-2/β-TCP (5.91 ± 1.27 mm² , p < .05), and rhFGF-2/CO₃ Ap (6.51 ± 1.49 mm² , p < .05) groups. Slight ankylosis was found in the rhFGF-2/β-TCP (1/9 sites), rhFGF-2/CO₃ Ap (3/10 sites), and rhFGF-2/DBBM (1/9 sites) groups.

CONCLUSIONS

Within their limitations, the present data indicate that DBBM seems to be a suitable carrier for rhFGF-2 and that rhFGF-2/DBBM treatment promotes favourable periodontal regeneration compared with rhFGF-2, rhFGF-2/β-TCP, and rhFGF-2/CO₃ Ap treatments in one-wall intra-bony defects.

Treatment of Chronic Periodontitis with Periodontal Surgery Including Regenerative Therapy Using Recombinant Human Fibroblast Growth Factor-2 and Papilla Preservation Technique: A Case Report with a Two-year Follow-up

This report describes a case of generalized chronic periodontitis requiring periodontal therapy including periodontal regeneration. The patient was a 59-year-old man who visited the Tokyo Dental College Suidobashi Hospital with the chief complaint of mobility in tooth #47. Periodontal examination at the first visit revealed that 32.1% of sites had a probing depth of ≥4 mm and 32.7% of sites bleeding on probing. Radiographic examination revealed vertical bone resorption in #26 and horizontal resorption in #12, 13, 42, and 43. Based on a clinical diagnosis of severe chronic periodontitis, initial periodontal therapy consisting of plaque control, scaling and root planing, occlusal adjustment, caries treatment, and placement of an occlusal splint was performed. Tooth #47 was extracted due to bone resorption extending as far as the root apex. After reevaluation, surgical periodontal treatment was performed at the selected site. Periodontal regenerative therapy using recombinant human fibroblast growth factor (rhFGF)-2 and papilla preservation technique was performed for #26. To reduce periodontal pockets, open flap debridement was implemented for #12, 13, 42, and 43. After reevaluation, the patient was placed on supportive periodontal therapy (SPT). Periodontal regenerative therapy with rhFGF-2 and modified papilla preservation technique yielded an improvement in angular bone resorption which has been properly maintained for two years. Periodontal therapy with open flap debridement resulted in an improvement in horizontal bone resorption. Continued SPT is needed to maintain a stable periodontal condition.

Periodontal tissue regeneration by transplantation of autologous adipose tissue-derived multi-lineage progenitor cells

Periodontitis is a chronic inflammatory disease that destroys tooth-supporting periodontal tissue. Current periodontal regenerative therapies have unsatisfactory efficacy; therefore, periodontal tissue engineering might be established by developing new cell-based therapies. In this study, we evaluated the safety and efficacy of adipose tissue-derived multi-lineage progenitor cells (ADMPC) autologous transplantation for periodontal tissue regeneration in humans. We conducted an open-label, single-arm exploratory phase I clinical study in which 12 periodontitis patients were transplanted with autologous ADMPCs isolated from subcutaneous adipose tissue. Each patient underwent flap surgery during which autologous ADMPCs were transplanted into the bone defect with a fibrin carrier material. Up to 36 weeks after transplantation, we performed a variety of clinical examinations including periodontal tissue inspection and standardized dental radiographic analysis. A 36-week follow-up demonstrated no severe transplantation-related adverse events in any cases. ADMPC transplantation reduced the probing pocket depth, improved the clinical attachment level, and induced neogenesis of alveolar bone. Therapeutic efficiency was observed in 2- or 3-walled vertical bone defects as well as more severe periodontal bone defects. These results suggest that autologous ADMPC transplantation might be an applicable therapy for severe periodontitis by inducing periodontal regeneration.

Enamel Matrix Derivatives for Periodontal Regeneration: Recent Developments and Future Perspectives

In the era of the growing population, the demand for dental care is increasing at a fast pace for both older and younger people. One of the dental diseases that has attracted significant research is periodontitis. Periodontal therapy aims to regenerate tissues that are injured by periodontal disease. During recent decades, various pioneering strategies and products have been introduced for restoring or regeneration of periodontal deficiencies. One of these involves the regeneration of tissues under guidance using enamel matrix derivatives (EMDs) or combinations of these. EMDs are mainly comprised of amelogenins, which is one of the most common biological agents used in periodontics. Multiple studies have been reported regarding the role of EMD in periodontal tissue regeneration; however, the extensive mechanism remains elusive. The EMDs could promote periodontal regeneration mainly through inducing periodontal attachment during tooth formation. EMD mimics biological processes that occur during periodontal tissue growth. During root development, enamel matrix proteins are formed on the root surface by Hertwig's epithelial root sheath cells, initiating the process of cementogenesis. This article reviews the challenges and recent advances in preclinical and clinical applications of EMDs in periodontal regeneration. Moreover, we discuss the current evidence on the mechanisms of action of EMDs in the regeneration of periodontal tissues.

Roles of the fibroblast growth factor signal transduction system in tissue injury repair

Following injury, tissue autonomously initiates a complex repair process, resulting in either partial recovery or regeneration of tissue architecture and function in most organisms. Both the repair and regeneration processes are highly coordinated by a hierarchy of interplay among signal transduction pathways initiated by different growth factors, cytokines and other signaling molecules under normal conditions. However, under chronic traumatic or pathological conditions, the reparative or regenerative process of most tissues in different organs can lose control to different extents, leading to random, incomplete or even flawed cell and tissue reconstitution and thus often partial restoration of the original structure and function, accompanied by the development of fibrosis, scarring or even pathogenesis that could cause organ failure and death of the organism. Ample evidence suggests that the various combinatorial fibroblast growth factor (FGF) and receptor signal transduction systems play prominent roles in injury repair and the remodeling of adult tissues in addition to embryonic development and regulation of metabolic homeostasis. In this review, we attempt to provide a brief update on our current understanding of the roles, the underlying mechanisms and clinical application of FGFs in tissue injury repair.

A Review of In Vivo and Clinical Studies Applying Scaffolds and Cell Sheet Technology for Periodontal Ligament Regeneration

Different approaches to develop engineered scaffolds for periodontal tissues regeneration have been proposed. In this review, innovations in stem cell technology and scaffolds engineering focused primarily on Periodontal Ligament (PDL) regeneration are discussed and analyzed based on results from pre-clinical in vivo studies and clinical trials. Most of those developments include the use of polymeric materials with different patterning and surface nanotopography and printing of complex and sophisticated multiphasic composite scaffolds with different compartments to accomodate for the different periodontal tissues' architecture. Despite the increased effort in producing these scaffolds and their undoubtable efficiency to guide and support tissue regeneration, appropriate source of cells is also needed to provide new tissue formation and various biological and mechanochemical cues from the Extraccellular Matrix (ECM) to provide biophysical stimuli for cell growth and differentiation. Cell sheet engineering is a novel promising technique that allows obtaining cells in a sheet format while preserving ECM components. The right combination of those factors has not been discovered yet and efforts are still needed to ameliorate regenerative outcomes towards the functional organisation of the developed tissues.

Periodontal Wound Healing and Regeneration: Insights for Engineering New Therapeutic Approaches

Periodontitis is a widespread inflammatory disease that leads to loss of the tooth supporting periodontal tissues. The few therapies available to regenerate periodontal tissues have high costs and inherent limitations, inspiring the development of new approaches. Studies have shown that periodontal tissues have an inherent capacity for regeneration, driven by multipotent cells residing in the periodontal ligament (PDL). The purpose of this review is to describe the current understanding of the mechanisms driving periodontal wound healing and regeneration that can inform the development of new treatment approaches. The biologic basis underlying established therapies such as guided tissue regeneration (GTR) and growth factor delivery are reviewed, along with examples of biomaterials that have been engineered to improve the effectiveness of these approaches. Emerging therapies such as those targeting Wnt signaling, periodontal cell delivery or recruitment, and tissue engineered scaffolds are described in the context of periodontal wound healing, using key in vivo studies to illustrate the impact these approaches can have on the formation of new cementum, alveolar bone, and PDL. Finally, design principles for engineering new therapies are suggested which build on current knowledge of periodontal wound healing and regeneration.

Visual and histological evaluation of the effects of trafermin in a dog oronasal fistula model

The standard procedure to treat oronasal fistula in dogs requires tooth extraction to close the fistula; hence, the subject would lose its tooth. In this study, trafermin was applied to four dog models with oronasal fistula to investigate the periodontal tissue regenerative effects of trafermin in the treatment without tooth extraction. A fistula was created along the palatal side of each upper canine tooth. One of the fistulae was filled with trafermin, whereas that on the contralateral side was left unfilled as a control. The results showed a significant decrease in the non-calcified periodontal tissue volume on the trafermin side after the fourth week. In addition, oronasal fistula closure was visually and histologically confirmed at the eighth week on the trafermin side of all four models.

Gingival recession treatment with enamel matrix derivative associated with coronally advanced flap and subepithelial connective tissue graft: a split-mouth randomized controlled clinical trial with molecular evaluation

OBJECTIVES

The goal of this study was to evaluate the impact of enamel matrix derivative (EMD) on periodontal healing after root coverage (RC) surgery, involving CAF in combination with SCTG, and to assess the molecular profile, verifying the inflammation level in early stage (1 and 2 weeks).

MATERIALS AND METHODS

Thirty-two recessions (RT1) were submitted to periodontal surgery with (test) or without (control) EMD. The clinical parameters analyzed on the day of surgery and 6 months after the surgical procedure were as follows: recession height and width, keratinized tissue height, percentual root coverage, and the gingival thickness of keratinized tissue. Moreover, the main inflammatory biomarkers and growth factors (IL-1β, IL-6, IL-8, FGF, MIP-1α and β, PDGF, TNF-α, and VEGF) were evaluated at baseline, 7, and 14 days after procedures.

RESULTS

The average root coverage was significantly higher in the test group as compared to the control group (86% vs. 66%, p = 0.008). The test side had significantly lesser final RH compared to the control side (p = 0.01). Also, there was a significant reduction of RW in both groups, with more significant results in the test group. KTH and GT were not significantly different at any time and group. After 14 days, the immunological analysis showed an increase of VEGF (p = 0.03) on the test group compared to the control side.

CONCLUSION

The use of EMD in RC surgeries resulted in a significantly higher RC, as well as a significant increase in VEGF expression, suggesting that EMD may contribute to the angiogenic and healing process.

CLINICAL RELEVANCE

EMD provided better results in root coverage treatment when associated with CAF and SCTG, beyond a greater releasing of angiogenic growth factor (VEGF), which enhanced the result.

Regenerative Medicine Technologies to Treat Dental, Oral, and Craniofacial Defects

Additive manufacturing (AM) is the automated production of three-dimensional (3D) structures through successive layer-by-layer deposition of materials directed by computer-aided-design (CAD) software. While current clinical procedures that aim to reconstruct hard and soft tissue defects resulting from periodontal disease, congenital or acquired pathology, and maxillofacial trauma often utilize mass-produced biomaterials created for a variety of surgical indications, AM represents a paradigm shift in manufacturing at the individual patient level. Computer-aided systems employ algorithms to design customized, image-based scaffolds with high external shape complexity and spatial patterning of internal architecture guided by topology optimization. 3D bioprinting and surface modification techniques further enhance scaffold functionalization and osteogenic potential through the incorporation of viable cells, bioactive molecules, biomimetic materials and vectors for transgene expression within the layered architecture. These computational design features enable fabrication of tissue engineering constructs with highly tailored mechanical, structural, and biochemical properties for bone. This review examines key properties of scaffold design, bioresorbable bone scaffolds produced by AM processes, and clinical applications of these regenerative technologies. AM is transforming the field of personalized dental medicine and has great potential to improve regenerative outcomes in patient care.

Limited Treatment Options for Diabetic Wounds: Barriers to Clinical Translation Despite Therapeutic Success in Murine Models

Significance: Millions of people worldwide suffer from diabetes mellitus and its complications, including chronic diabetic wounds. To date, there are few widely successful clinical therapies specific to diabetic wounds beyond general wound care, despite the vast number of scientific discoveries in the pathogenesis of defective healing in diabetes. Recent Advances: In recent years, murine animal models of diabetes have enabled the investigation of many possible therapeutics for diabetic wound care. These include specific cell types, growth factors, cytokines, peptides, small molecules, plant extracts, microRNAs, extracellular vesicles, novel wound dressings, mechanical interventions, bioengineered materials, and more. Critical Issues: Despite many research discoveries, few have been translated from their success in murine models to clinical use in humans. This massive gap between bench discovery and bedside application begs the simple and critical question: what is still missing? The complexity and multiplicity of the diabetic wound makes it an immensely challenging therapeutic target, and this lopsided progress highlights the need for new methods to overcome the bench-to-bedside barrier. How can laboratory discoveries in animal models be effectively translated to novel clinical therapies for human patients? Future Directions: As research continues to decipher deficient healing in diabetes, new approaches and considerations are required to ensure that these discoveries can become translational, clinically usable therapies. Clinical progress requires the development of new, more accurate models of the human disease state, multifaceted investigations that address multiple critical components in wound repair, and more innovative research strategies that harness both the existing knowledge and the potential of new advances across disciplines.

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.

The Role of Type 2 Fibroblast Growth Factor in Periodontal Therapy

The prevalence of periodontitis is around 20-50% in the global population. If it is not treated, it can cause tooth loss. Periodontal treatment aims at preserving the patient's teeth from various damages, including infection control and restoring lost periodontal tissue. The periodontium has great biological regenerative potential, and several biomaterials can be used to improve the outcome of periodontal treatment. To achieve the goal of periodontal tissue regeneration, numerous studies have used fibroblast growth factor 2 (FGF2) to stimulate the regeneration of both the soft tissue and bone. FGF2 induced a significant increment in the percentage of bone fill, bone mineral levels of the defect sites, length of the regenerated periodontal ligament, angiogenesis, connective tissue formation on the root surface, formation of dense fibers bound to the alveolar bone and newly synthesized cementum in teeth. This review will open further avenues to better understand the FGF2 therapy for periodontal regeneration.

Decitabine Inhibits Bone Resorption in Periodontitis by Upregulating Anti-Inflammatory Cytokines and Suppressing Osteoclastogenesis

DNA methylation controls several inflammatory genes affecting bone homeostasis. Hitherto, inhibition of DNA methylation in vivo in the context of periodontitis and osteoclastogenesis has not been attempted. Ligature-induced periodontitis in C57BL/6J mice was induced by placing ligature for five days with Decitabine (5-aza-2′-deoxycytidine) (1 mg/kg/day) or vehicle treatment. We evaluated bone resorption, osteoclast differentiation by tartrate-resistant acid phosphatase (TRAP) and mRNA expression of anti-inflammatory molecules using cluster differentiation 14 positive (CD14⁺) monocytes from human peripheral blood. Our data showed that decitabine inhibited bone loss and osteoclast differentiation experimental periodontitis, and suppressed osteoclast CD14⁺ human monocytes; and conversely, that it increased bone mineralization in osteoblastic cell line MC3T3-E1 in a concentration-dependent manner. In addition to increasing IL10 (interleukin-10), TGFB (transforming growth factor beta-1) in CD14⁺ monocytes, decitabine upregulated KLF2 (Krüppel-like factor-2) expression. Overexpression of KLF2 protein enhanced the transcription of IL10 and TGFB. On the contrary, site-directed mutagenesis of KLF2 binding site in IL10 and TFGB abrogated luciferase activity in HEK293T cells. Decitabine reduces bone loss in a mouse model of periodontitis by inhibiting osteoclastogenesis through the upregulation of anti-inflammatory cytokines via KLF2 dependent mechanisms. DNA methyltransferase inhibitors merit further investigation as a possible novel therapy for periodontitis.

Effect of Aging on Homeostasis in the Soft Tissue of the Periodontium: A Narrative Review

Aging is characterized by a progressive decline or loss of physiological functions, leading to increased susceptibility to disease or death. Several aging hallmarks, including genomic instability, cellular senescence, and mitochondrial dysfunction, have been suggested, which often lead to the numerous aging disorders. The periodontium, a complex structure surrounding and supporting the teeth, is composed of the gingiva, periodontal ligament, cementum, and alveolar bone. Supportive and protective roles of the periodontium are very critical to sustain life, but the periodontium undergoes morphological and physiological changes with age. In this review, we summarize the current knowledge of molecular and cellular physiological changes in the periodontium, by focusing on soft tissues including gingiva and periodontal ligament.

Growth Factors, Carrier Materials, and Bone Repair

This chapter provides an overview of the growth factors active in bone regeneration and healing. Both normal and impaired bone healing are discussed, with a focus on the spatiotemporal activity of the various growth factors known to be involved in the healing response. The review highlights the activities of most important growth factors impacting bone regeneration, with a particular emphasis on those being pursued for clinical translation or which have already been marketed as components of bone regenerative materials. Current approaches the use of bone grafts in clinical settings of bone repair (including bone grafts) are summarized, and carrier systems (scaffolds) for bone tissue engineering via localized growth factor delivery are reviewed. The chapter concludes with a consideration of how bone repair might be improved in the future.

Effects of combined use of recombinant human fibroblast growth factor-2 and β-tricalcium phosphate on ridge preservation in dehiscence bone defects after tooth extraction: A split-mouth study in dogs

BACKGROUND AND OBJECTIVE

Following tooth extraction, bone resorption is especially severe in cases complicated with buccal dehiscence bone defects. To minimize this, various bone graft materials have been used for alveolar ridge preservation. This study aimed to evaluate additional effects of the concomitant use of recombinant human fibroblast growth factor-2 (rhFGF-2) with β-tricalcium phosphate (β-TCP) on ridge preservation in a dehiscence defect model after tooth extraction in dogs.

MATERIALS AND METHODS

The maxillary first premolars of six beagle dogs were extracted and dehiscence defects of 4 × 4 × 5 mm (mesio-distal width × bucco-palatal width × depth) were created. Bilateral defects were filled with β-TCP combined with 0.3% (w/v) rhFGF-2 (test sites) or the scaffold alone (control sites). Twelve weeks post-surgery, histologic and histometric evaluations were performed.

RESULTS

Morphological measurements using micro-computed tomography revealed a significantly greater bone volume at the test sites (48.9 ± 9.06 mm³ ) than at the control sites (38.8 ± 7.24 mm³ ). Horizontal widths of the alveolar ridge at the coronal and middle position at the test sites (2.18 ± 0.71 mm, 2.93 ± 0.53 mm) were significantly greater than those at the control sites (1.47 ± 0.41 mm, 2.36 ± 0.45 mm, respectively). Regarding the histological parameters, the occupation rate of mineralized bone in the original defects was slightly higher at the test sites (44.07 ± 10.19%) than that at the control site (41.15 ± 6.56%).

CONCLUSIONS

These results indicate that the adjunct use of rhFGF-2 with β-TCP is effective for alveolar ridge preservation in fresh extraction sockets with dehiscence defects.

Impact of adjunctive procedures on recombinant human fibroblast growth factor-2-mediated periodontal regeneration therapy: A retrospective study

BACKGROUND

Human fibroblast growth factor-2 (rhFGF-2) therapy has been used for periodontal tissue regeneration. However, few studies have reported their adjunctive procedures based on strategy of tissue engineering. The aim of this retrospective study is to assess the adjunctive effects of modified papilla preservation technique (mPPT) and combination with autogenous bone grafts (AG) on the rhFGF-2 therapy.

METHODS

Total of 44 sites underwent rhFGF-2 therapies and the evaluations in the survey periods. The primary outcome was set to the radiographic bone fill by radiographic examinations at 6 and 12 months after surgeries. We analyzed the correlation between influencing factors and the primary outcome, and differences of therapeutic effect by combination therapy with mPPT and that with AG.

RESULTS

After surgeries, probing depth (PD), clinical attachment level (CAL) and bone defects significantly improved. The improvements of radiographic bone fill were significantly positive correlated with a number of bone walls, combination with mPPT, and AG at 6 months after surgeries, and with combination with mPPT and AG at 12 months after surgeries. The significant differences of improvements of radiographic bone fill were demonstrated between combination with or without mPPT at 12 months after surgeries, and with or without AG at 6 and 12 months after surgeries. Moreover, the multiple linear regression analysis for the radiographic bone fill indicated the significant regression coefficient with conducts of mPPT.

CONCLUSIONS

mPPT and AG had powerfully adjunctive effects on rhFGF-2 therapy. Further studies are needed in order to verify by randomized clinical trials.

Periodontal surgery using rhFGF-2 with deproteinized bovine bone mineral or rhFGF-2 alone: 2-year follow-up of a randomized controlled trial

AIM

To compare outcomes of rhFGF-2 + DBBM therapy with rhFGF-2 alone in the treatment of intrabony defects. This study provides 2-year follow-up results from the previous randomized controlled trial.

MATERIALS AND METHODS

Defects were randomly allocated to receive rhFGF-2 + DBBM (test) or rhFGF-2 (control). Treated sites were re-evaluated at 2 years postoperatively, using original clinical and patient-centred measures.

RESULTS

Thirty-eight sites were available for re-evaluation. At 2 years, both groups showed a significant improvement in clinical attachment level (CAL) from baseline. A gain in CAL of 3.4 ± 1.3 mm in the test group and 3.1 ± 1.5 mm in the control group was found. No significant inter-group difference was noted. Both groups showed a progressive increase in radiographic bone fill (RBF). The test treatment yielded greater RBF (56%) compared with the control group (41%). The control treatment performed better in contained defects in terms of CAL and RBF. There was no significant difference in patient-reported outcomes between groups.

CONCLUSIONS

At 2-year follow-up, the test and cotrol treatments were similarly effective in improving CAL, whereas the test treatment achieved a significantly greater RBF. In both treatments, favourable clinical, radiographic, and patient-reported outcomes can be sustained for at least 2 years.

TRIAL REGISTRATION

The University Hospital Medical Information Network-Clinical Trials Registry (UMIN-CTR) 000025257.

Micro-Architectural Investigation of Teleost Fish Rib Inducing Pliant Mechanical Property

Despite the fact that various reports have been discussing bone tissue regeneration, precise bone tissue manipulation, such as controlling the physical properties of the regenerated bone tissue, still remains a big challenge. Here, we focused on the teleost fish ribs showing flexible and tough mechanical properties to obtain a deeper insight into the structural and functional features of bone tissue from different species, which would be valuable for the superior design of bone-mimicking materials. Herein, we examined their compositions, microstructure, histology, and mechanical properties. The first rib of Carassius langsdorfii showed a higher Young's modulus with a small region of chondrocyte clusters compared with other smaller ribs. In addition, highly oriented collagen fibers and osteocytes were observed in the first rib, indicating that the longest first rib would be more mature. Moreover, the layer-by-layer structure of the oriented bone collagen was observed in each rib. These microarchitectural and compositional findings of fish rib bone would give one the useful idea to reproduce such a highly flexible rib bone-like material.

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.

An in-vivo Intraoral Defect Model for Assessing the Use of P11-4 Self-Assembling Peptide in Periodontal Regeneration

Periodontal disease is one of the most common diseases worldwide. It has a significant impact on oral health and subsequently the individual’s quality of life. However, optimal regeneration of periodontal tissues, using current treatments, has yet to be achieved. Peptide self-assembly has provided a step-change in nanobiotechnology and regenerative medicine fields. Our aim was to investigate the effects of a self-assembling peptide (SAP; P₁₁-4) on periodontal regeneration in a preclinical model. Twenty-six bilateral maxillary critical-sized periodontal defects were created surgically in 13 rats. Defects on one side of the mouth were filled with P₁₁-4 hydrogel; the contra-lateral defect was untreated (control). Rats were sacrificed immediately post-surgery (time 0) and after 2 and 4 weeks. Retrieved maxillae were processed for histological, immunohistochemical, and histomorphometric assessments. The results of histological analysis showed greater organization of periodontal fibers in defects treated with P₁₁-4, at both time points, when compared to untreated defects. Histomorphometry showed that treated defects had both a significant increase in functional periodontal ligament length and a reduction in epithelial down growth after 4 weeks. At 2 weeks, treated defects showed a significant increase in expression of osteocalcin and osteoprotegerin as judged by immunohistochemistry. Also, a significantly higher osteoprotegerin/RANKL ratio was shown in treated defects. In conclusion, the results demonstrated enhanced regeneration of periodontal tissues when SAP P₁₁-4 was used to fill periodontal defects in rats. The findings of this study suggest that SAP P₁₁-4 is a promising novel candidate for periodontal regenerative therapy. Further investigations are required for optimization before clinical use.