Potential For Periodontal Regeneration Research Articles

High-yield nanovesicles extruded from dental follicle stem cells promote the regeneration of periodontal tissues as an alternative of exosomes.

To identify an optimized strategy for the large-scale production of nanovesicles (NVs) that preserve the biological properties of exosomes (EXOs) for use in periodontal regeneration. NVs from dental follicle stem cells (DFSCs) were prepared through extrusion, and EXOs from DFSCs were isolated. The yield of both extruded NVs (eNVs) and EXOs were quantified through protein concentration and particle number analyses. Their pro-migration, pro-proliferation and pro-osteogenesis capacities were compared subsequently in vitro. Additionally, proteomics analysis was conducted. To further evaluate the periodontal regeneration potential of eNVs and EXOs, they were incorporated into collagen sponges and transplanted into periodontal defects in rats. In vivo imaging and H&E staining were utilized to verify their biodistribution and safety. Micro-Computed Tomography analysis and histological staining were performed to examine the regeneration of periodontal tissues. The yield of eNVs was nearly 40 times higher than that of EXOs. Interestingly, in vitro experiments indicated that the pro-migration and pro-proliferation abilities of eNVs were superior, and the pro-osteogenesis potential was comparable to EXOs. More importantly, eNVs exhibited periodontal regenerative potential similar to that of EXOs. Extrusion has proven to be an efficient method for generating numerous eNVs with the potential to replace EXOs in periodontal regeneration.

Weissella cibaria EIR/P2-derived exopolysaccharide: A novel alternative to conventional biomaterials targeting periodontal regeneration

Healing and regeneration of periodontium are considered as a complex physiological process. Therefore, treatments need to be addressed with highly effective components modulating the multiple pathways. In this study, exopolysaccharide (EPS) produced by Weissella cibaria EIR/P2, was partially purified from the culture supernatant and subjected to characterization within the aim of evaluating its potential for periodontal regeneration. High-Performance Liquid Chromatography analysis revealed a single-peak corresponding to the glucose which identified the EPS as dextran. Fourier transform-infrared spectra were also displayed characteristic peaks for polysaccharides. According to the results of gel permeation/size exclusion-chromatography, the molecular mass was determined to be 8 × 106 Da. To clarify its anti-bacterial activity on Streptococcus mutans, effects on viability and biofilm formation was evaluated. At 50 mg/mL, dextran exhibited a bactericidal effect with 70% inhibition on biofilm formation. Besides, dose-dependent antioxidant effects were also detected. The efficacy of dextran in enhancing the viability of human periodontal ligament fibroblast cells (hPDLFCs) was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide (MTT) assay, and an increase was observed in the viability of hPDLFCs. In conclusion, dextran derived from W. cibaria can be potentially used as a multi-functional bioactive polymer in the design of new therapeutic strategies to promote healing and regeneration of periodontium.

Nanomaterials for Periodontal Tissue Engineering: Chitosan-Based Scaffolds. A Systematic Review.

Introduction. Several biomaterials are used in periodontal tissue engineering in order to obtain a three-dimensional scaffold, which could enhance the oral bone regeneration. These novel biomaterials, when placed in the affected area, activate a cascade of events, inducing regenerative cellular responses, and replacing the missing tissue. Natural and synthetic polymers can be used alone or in combination with other biomaterials, growth factors, and stem cells. Natural-based polymer chitosan is widely used in periodontal tissue engineering. It presents biodegradability, biocompatibility, and biological renewability properties. It is bacteriostatic and nontoxic and has hemostatic and mucoadhesive capacity. The aim of this systematic review is to obtain an updated overview of the utilization and effectiveness of chitosan-based scaffold (CS-bs) in the alveolar bone regeneration process. Materials and Methods. During database searching (using PubMed, Cochrane Library, and CINAHL), 72 items were found. The title, abstract, and full text of each study were carefully analyzed and only 22 articles were selected. Thirteen articles were excluded based on their title, five after reading the abstract, twenty-six after reading the full text, and six were not considered because of their publication date (prior to 2010). Quality assessment and data extraction were performed in the twelve included randomized controlled trials. Data concerning cell proliferation and viability (CPV), mineralization level (M), and alkaline phosphatase activity (ALPA) were recorded from each article Results. All the included trials tested CS-bs that were combined with other biomaterials (such as hydroxyapatite, alginate, polylactic-co-glycolic acid, polycaprolactone), growth factors (basic fibroblast growth factor, bone morphogenetic protein) and/or stem cells (periodontal ligament stem cells, human jaw bone marrow-derived mesenchymal stem cells). Values about the proliferation of cementoblasts (CB) and periodontal ligament cells (PDLCs), the activity of alkaline phosphatase, and the mineralization level determined by pure chitosan scaffolds resulted in lower than those caused by chitosan-based scaffolds combined with other molecules and biomaterials. Conclusions. A higher periodontal regenerative potential was recorded in the case of CS-based scaffolds combined with other polymeric biomaterials and bioceramics (bio compared to those provided by CS alone. Furthermore, literature demonstrated that the addition of growth factors and stem cells to CS-based scaffolds might improve the biological properties of chitosan.

Comparative assessment of periodontal regeneration in periodontal intraosseous defects treated with PepGen P-15 unaided or in blend with platelet-rich fibrin: A clinical and high-resolution computed tomography scan-assisted volumetric analysis.

Background:PepGen P-15, a xenograft, has proven its periodontal regenerative potential. Platelet-rich fibrin (PRF) is an autologous platelet concentrate which too contributes to periodontal redevelopment through the release of different polypeptide progression factors. The present study intended to evaluate the regenerative potential of PepGen P-15 xenograft when used unaccompanied or in blend with PRF in periodontal intraosseous defects in humans through clinical and a novel computed tomography (CT) scan analysis technique.Materials and Methods:Twelve chronic periodontitis individuals with paired periodontal intraosseous defects were randomly treated either with PepGen P-15 exclusively (Control/Group A) or in concoction with PRF (Test/Group B) utilizing split-mouth study design. Pocket probing depth (PPD), relative attachment level (RAL), and relative position of gingival margin were assessed at 3- and 6-month interval, whereas the linear and volumetric bone defect regeneration were assessed at 6 months postoperatively using CT scan.Results:Both the groups validated statistically significant PPD reduction, RAL gain at 3 and 6 months, but on intergroup comparison, test group CT images revealed significantly greater linear bone gain and volumetric bone gain, with mean difference of 0.73 ± 0.28 (P = 0.018) and 2.70 ± 1.36 (P = 0.06) at 6 months in comparison to the baseline data.Conclusions:PepGen P-15 and PRF blend had better regeneration potential for the management of intrabony defects. Further long-term investigations on large sample size are recommended to authenticate the same.

Multiphasic Collagen Scaffolds for Engineered Tissue Interfaces

AbstractHard–soft tissue interfaces pose unique challenges for regeneration due to architectural, mechanical, and compositional changes between tissues, which are difficult to incorporate into tissue engineering scaffolds. Multiphasic scaffolds are needed to better mimic structural and chemical changes through the incorporation of layers with distinct properties. A particular challenge in the production of multilayered constructs is achieving cohesion between layers. Herein, a novel system is developed, which combines sequential collagen self‐assembly and diffusion gradients in mineralization to produce multiphasic collagen scaffolds that have intrinsic connectivity and porosity between layers, with no need for adhesives or heat treatments. The scaffolds incorporate mineralized layers, wherein the mineralized collagen fibrils have intrafibrillar oriented mineral resembling bone, alongside unmineralized layers. The interface between mineralized and unmineralized layers is sharp and well defined, with nonmineralized fibrils inserting into the mineralized layer to create mechanical interlock and cohesion. Inspired by the complex architecture of the periodontal attachment apparatus (bone–ligament–cementum), it is demonstrated that the model system can be applied to the development of a trilayered collagen scaffold with potential for periodontal regeneration.

Efficacy of stem cells on periodontal regeneration: Systematic review of pre-clinical studies.

This systematic review aims to evaluate mesenchymal stem cells (MSC) periodontal regenerative potential in animal models. MEDLINE, EMBASE and LILACS databases were searched for quantitative pre-clinical controlled animal model studies that evaluated the effect of local administration of MSC on periodontal regeneration. The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines. Twenty-two studies met the inclusion criteria. Periodontal defects were surgically created in all studies. In seven studies, periodontal inflammation was experimentally induced following surgical defect creation. Differences in defect morphology were identified among the studies. Autogenous, alogenous and xenogenous MSC were used to promote periodontal regeneration. These included bone marrow-derived MSC, periodontal ligament (PDL)-derived MSC, dental pulp-derived MSC, gingival margin-derived MSC, foreskin-derived induced pluripotent stem cells, adipose tissue-derived MSC, cementum-derived MSC, periapical follicular MSC and alveolar periosteal cells. Meta-analysis was not possible due to heterogeneities in study designs. In most of the studies, local MSC implantation was not associated with adverse effects. The use of bone marrow-derived MSC for periodontal regeneration yielded conflicting results. In contrast, PDL-MSC consistently promoted increased PDL and cementum regeneration. Finally, the adjunct use of MSC improved the regenerative outcomes of periodontal defects treated with membranes or bone substitutes. Despite the quality level of the existing evidence, the current data indicate that the use of MSC may provide beneficial effects on periodontal regeneration. The various degrees of success of MSC in periodontal regeneration are likely to be related to the use of heterogeneous cells. Thus, future studies need to identify phenotypic profiles of highly regenerative MSC populations.

Periodontal-Derived Mesenchymal Cell Sheets Promote Periodontal Regeneration in Inflammatory Microenvironment.

In this study, we investigated the periodontal regenerative potential of dental follicle cell (DFC) sheets and periodontal ligament cell (PDLC) sheets in the simulating inflammatory microenvironment of periodontitis, to confirm their regenerative potential for clinical application and explain the possible mechanism. The biological characteristics of DFC sheets and PDLC sheets were explored in lipopolysaccharide from Porphyromonas gingivalis (P. gingivalis LPS)-induced inflammation microenvironment in vitro, then cell sheets were transplanted into canine periodontal defects with experimental periodontitis in situ for 3 months. The results showed that P. gingivalis LPS greatly impaired the differentiation of PDLC sheets, whereas promoted gene expression of bone sialoprotein (BSP), osteopontin (OPN), and periostin (POSTN) in DFC sheets. LPS activated toll-like receptor 4 and NF-κB p65 phosphorylation in PDLC sheets. In experimental periodontitis, new periodontal attachment could be obtained in both PDLC sheets and DFC sheets. However, the complete periodontal regeneration, including periodontal ligament-cementum complex structure was observed only in DFC sheet groups, which also showed more alveolar bone formation than PDLC sheets. These results suggest that DFC sheets were more effective for periodontal regeneration in chronic inflammatory microenvironment of periodontitis. It is probably because of their ability to adapt the inflammatory environment and strong capacity to promote periodontal regeneration. This approach provides a tangible pathway toward clinical translation.

Adenovirus-mediated transfer of hepatocyte growth factor gene to human dental pulp stem cells under good manufacturing practice improves their potential for periodontal regeneration in swine.

IntroductionPeriodontitis is one of the most widespread infectious diseases in humans. We previously promoted significant periodontal tissue regeneration in swine models with the transplantation of autologous periodontal ligament stem cells (PDLSCs) and PDLSC sheet. We also promoted periodontal tissue regeneration in a rat model with a local injection of allogeneic bone marrow mesenchymal stem cells. The purpose of the present study is to investigate the roles of the hepatocyte growth factor (HGF) and human dental pulp stem cells (DPSCs) in periodontal tissue regeneration in swine.MethodIn the present study, we transferred an adenovirus that carried HGF gene into human DPSCs (HGF-hDPSCs) under good manufacturing practice (GMP) conditions. These cells were then transplanted into a swine model for periodontal regeneration. Twenty miniature pigs were used to generate periodontitis with bone defect of 5 mm in width, 7 mm in length, and 3 mm in depth. After 12 weeks, clinical, radiological, quantitative and histological assessment of regenerated periodontal tissues was performed to compare periodontal regeneration in swine treated with cell implantation.ResultsOur study showed that injecting HGF-hDPSCs into this large animal model could significantly improve periodontal bone regeneration and soft tissue healing. A hDPSC or HGF-hDPSC sheet showed superior periodontal tissue regeneration compared to the injection of dissociated cells. However, the sheets required surgical placement; thus, they were suitable for surgically-managed periodontitis treatments. The adenovirus-mediated transfer of the HGF gene markedly decreased hDPSC apoptosis in a hypoxic environment or in serum-free medium, and it increased blood vessel regeneration.ConclusionThis study indicated that HGF-hDPSCs produced under GMP conditions significantly improved periodontal bone regeneration in swine; thus, this method represents a potential clinical application for periodontal regeneration.Electronic supplementary materialThe online version of this article (doi:10.1186/s13287-015-0244-5) contains supplementary material, which is available to authorized users.

TlR expression profile of human gingival margin-derived stem progenitor cells

BackgroundGingival margin-derived stem/progenitor cells (G-MSCs) show remarkable periodontal regenerative potential in vivo. During regeneration, G-MSCs may interact with their inflammatory environment via toll-like-receptors (TLRs). The present study aimed to depict the G-MSCs TLRs expression profile.Material and MethodsCells were isolated from free gingival margins, STRO-1-immunomagnetically sorted and seeded to obtain single colony forming units (CFUs). G-MSCs were characterized for CD14, CD34, CD45, CD73, CD90, CD105, CD146 and STRO-1 expression, and for multilineage differentiation potential. Following G-MSCs’ incubation in basic or inflammatory medium (IL-1β, IFN-γ, IFN-α, TNF-α) a TLR expression profile was generated.ResultsG-MSCs showed all stem/progenitor cells’ characteristics. In basic medium G-MSCs expressed TLRs 1, 2, 3, 4, 5, 6, 7, and 10. The inflammatory medium significantly up-regulated TLRs 1, 2, 4, 5, 7 and 10 and diminished TLR 6 (p≤0.05, Wilcoxon-Signed-Ranks-Test).ConclusionsThe current study describes for the first time the distinctive TLRs expression profile of G-MSCs under uninflamed and inflamed conditions. Key words:Stem cells, TLR, gingiva, polymerase chain reaction, FACS.

Periodontal tissue regeneration using enzymatically solidified chitosan hydrogels with or without cell loading.

This study is aimed to evaluate the in vivo biocompatibility and periodontal regenerative potential of enzymatically solidified chitosan hydrogels with or without incorporated periodontal ligament cells (PDLCs). To this end, chitosan hydrogels, with (n=8; CHIT+CELL) or without (n=8; CHIT) fluorescently labeled PDLCs, were prepared and transplanted into rat intrabony periodontal defects; untreated defects were used as empty controls (n=8; EMPTY). After 4 weeks, maxillae were harvested, decalcified, and used for histological, histomorphometrical, and immunohistochemical assessments. The results showed that PDLCs remained viable upon encapsulation within chitosan hydrogels before transplantation. Histological analysis demonstrated that the chitosan hydrogels were largely degraded after 4 weeks of implantation, without any adverse reaction in the surrounding tissue. In terms of periodontal regeneration, alveolar bone height, alveolar bone area, and epithelial downgrowth were comparable for CHIT, CHIT+CELL, as well as EMPTY groups. In contrast, both CHIT and CHIT+CELL showed a significant increase in functional ligament length compared with EMPTY. From a cellular perspective, the contribution of chitosan hydrogel-incorporated cells to the periodontal regeneration could not be ascertained, as no signal from transplanted PDLCs could be detected at 4 weeks posttransplantation. The results demonstrated that enzymatically solidified chitosan hydrogels are highly biocompatible and biodegradable. Moreover, chitosan hydrogels without cell loading can improve periodontal regeneration in terms of functional ligament length, indicating the great potential of this hydrogel in clinical applications. Further work on the use of chitosan hydrogels as cell carriers is required.

Isolation and characterisation of human gingival margin-derived STRO-1/MACS(+) and MACS(-) cell populations.

Recently, gingival margin-derived stem/progenitor cells isolated via STRO-1/magnetic activated cell sorting (MACS) showed remarkable periodontal regenerative potential in vivo. As a second-stage investigation, the present study's aim was to perform in vitro characterisation and comparison of the stem/progenitor cell characteristics of sorted STRO-1-positive (MACS+) and STRO-1-negative (MACS−) cell populations from the human free gingival margin. Cells were isolated from the free gingiva using a minimally invasive technique and were magnetically sorted using anti-STRO-1 antibodies. Subsequently, the MACS+ and MACS− cell fractions were characterized by flow cytometry for expression of CD14, CD34, CD45, CD73, CD90, CD105, CD146/MUC18 and STRO-1. Colony-forming unit (CFU) and multilineage differentiation potential were assayed for both cell fractions. Mineralisation marker expression was examined using real-time polymerase chain reaction (PCR). MACS+ and MACS− cell fractions showed plastic adherence. MACS+ cells, in contrast to MACS− cells, showed all of the predefined mesenchymal stem/progenitor cell characteristics and a significantly higher number of CFUs (P<0.01). More than 95% of MACS+ cells expressed CD105, CD90 and CD73; lacked the haematopoietic markers CD45, CD34 and CD14, and expressed STRO-1 and CD146/MUC18. MACS− cells showed a different surface marker expression profile, with almost no expression of CD14 or STRO-1, and more than 95% of these cells expressed CD73, CD90 and CD146/MUC18, as well as the haematopoietic markers CD34 and CD45 and CD105. MACS+ cells could be differentiated along osteoblastic, adipocytic and chondroblastic lineages. In contrast, MACS− cells demonstrated slight osteogenic potential. Unstimulated MACS+ cells showed significantly higher expression of collagen I (P<0.05) and collagen III (P<0.01), whereas MACS− cells demonstrated higher expression of osteonectin (P<0.05; Mann–Whitney). The present study is the first to compare gingival MACS+ and MACS− cell populations demonstrating that MACS+ cells, in contrast to MACS− cells, harbour stem/progenitor cell characteristics. This study also validates the effectiveness of the STRO-1/MACS+ technique for the isolation of gingival stem/progenitor cells. Human free gingival margin-derived STRO-1/MACS+ cells are a unique renewable source of multipotent stem/progenitor cells.

Periodontal regeneration employing gingival margin‐derived stem/progenitor cells: an animal study

This study investigated the periodontal regenerative potential of gingival margin-derived multipotent postnatal stem/progenitor cells. Periodontal defects were induced at six sites in eight miniature pigs in the premolar/molar area (-4weeks). Autologous cells isolated from the gingival margin were magnetically sorted using STRO-1 antibodies and characterized flow cytometrically for the expression of CD14, CD31, CD34, CD45, CD117 and STRO-1 surface markers. Colony formation and multilineage differentiation potential were tested. The cells were expanded and loaded on deproteinized bovine cancellous bone (DBCB) and Collagen scaffolds. Within every miniature pig, six periodontal defects were randomly treated with loaded-DBCB (test group 1), unloaded-DBCB (control group 1), loaded-Collagen scaffolds (test group 2), unloaded-Collagen scaffolds (control group 1), scaling and root planing (negative control 1) or left untreated (negative control 2). Differences in clinical attachment level (ΔCAL), probing depth (ΔPD), gingival recession (ΔGR) and radiographic defect volume (ΔRDV) between baseline and 12weeks, as well as histological attachment level (HAL), junctional epithelium length (JE) and connective tissue adhesion (CTA) after 12weeks were evaluated. Isolated cells showed stem/progenitor cell characteristics. Cell-loaded scaffolds showed higher ΔCAL, ΔPD, ΔGR, HAL and lower JE and CTA compared with unloaded scaffolds and negative controls. The sort of scaffold had no significant influence on the measured outcomes. Gingival margin-derived stem/progenitor cells show significant periodontal regenerative potential.

Gene-Modified Stem Cells Combined with Rapid Prototyping Techniques: A Novel Strategy for Periodontal Regeneration

Periodontal disease, a worldwide prevalent chronic disease in adults, is characterized by the destruction of the periodontal supporting tissue including the cementum, periodontal ligament and alveolar bone. The regeneration of damaged periodontal tissue is the main goal of periodontal treatment. Because conventional periodontal treatments remain insufficient to attain complete and reliable periodontal regeneration, periodontal tissue engineering has emerged as a prospective alternative method for improving the regenerative capacity of periodontal tissue. However, the potential of periodontal regeneration seems to be limited by the understanding of the cellular and molecular events in the formation of periodontal tissue and by the insufficient collaboration of multi-disciplinary research that periodontal tissue engineering involves. In this paper, we first reviewed the recent advancements in stem cells, signaling factors, and scaffolds that relate to periodontal regeneration. Then we speculate that specific genes would improve regenerative capacity of these stem cells, which could differentiate into cementoblasts, osteoblasts and fibroblasts. In addition, the 3D scaffolds that mimic the different structure and physiologic functions of natural fibro-osseous tissue could be fabricated by rapid prototyping (RP) techniques. It was therefore hypothesized that gene-modified stem cells combined with rapid prototyping techniques would be a new strategy to promote more effective and efficient periodontal regeneration.

Physiological features of periodontal regeneration and approaches for periodontal tissue engineering utilizing periodontal ligament cells

Experimental studies have shown that the potential of periodontal regeneration seems to be limited by the regenerative capacity of the cells involved. The regeneration of damaged periodontal tissues is mediated by various periodontal cells and is regulated by a vast array of extracellular matrix informational molecules that induce both selective and nonselective responses in different cell lineages and their precursors. In this paper, we first review periodontal ligament tissue and its different cell subpopulations including fibroblasts and paravascular stem cells, and their functions during the development and homeostasis of periodontal tissues. Because conventional periodontal regeneration methods remain insufficient to obtain a complete and reliable periodontal regeneration, the concept of periodontal tissue engineering has been based on the generation of the conditions necessary to improve the healing of periodontal tissues. Additionally, the potential of periodontal ligament cells for use in periodontal tissue engineering to overcome the limitations of conventional periodontal regenerative therapies is discussed, followed by an update of the recent progress and future directions of research utilizing periodontal ligament cells for predictable periodontal regeneration.

Enhanced proliferation, attachment and osteopontin expression by porcine periodontal cells exposed to Emdogain ®

Emdogain (EMD) is an enamel matrix derivative extracted from developing porcine teeth with demonstrated periodontal regenerative potential. EMD has been shown to influence a number of properties of periodontal ligament cells including proliferation, cell attachment and matrix synthesis. To date, the effect of EMD on the epithelial cell rests of Malassez (ERM) is unknown. In this study, periodontal ligament fibroblasts, ERM, alveolar bone cells and gingival fibroblasts were obtained from porcine periodontal ligament, alveolar bone and gingiva. This study investigated, in vitro, the effect of EMD at three concentrations on proliferation, cell attachment and expression of mRNA for two mineralised tissue-related proteins (osteopontin and bone sialoprotein). As for other periodontal cells, the ERM proliferative response was enhanced by EMD. Attachment assays revealed a highly significant increase for ERM and gingival fibroblasts after EMD treatment at all concentrations. This study has also shown that EMD stimulated expression of osteopontin mRNA by ERM and alveolar bone cells. The results from this study provide evidence that EMD enhanced cellular events related with proliferation, attachment and osteopontin mRNA expression by porcine periodontal cells, in a manner consistent with its role in periodontal regenerative therapy.

Periodontal Regenerative Potential of Autogenous Periodontal Ligament Grafts in Class II Furcation Defects

The aim of the present study was to evaluate the regenerative potential of autogenous periodontal ligament (PDL) grafts in the treatment of Class II furcation defects. Twenty mandibular Class II furcation defects from 10 systemically healthy patients with chronic periodontitis were selected. In experimental defects, flaps were coronally positioned following placing autogenous PDL grafts that were obtained from third molars; in controls, coronally advanced flap procedure without graft was applied. Clinical measurements including plaque index, gingival index, probing depth (PD), vertical and horizontal clinical attachment level (CAL), and gingival recession (GR) were obtained at baseline and after 3 and 6 months postoperatively. Vertical and horizontal defect fill was evaluated with open clinical measurements at initial surgery and reentry after 6 months. Gingival biopsies from the experimental and control defects were obtained at reentry and evaluated histopathologically in order to examine the soft tissue response towards PDL grafts. Sites treated with PDL grafts demonstrated significant improvement in vertical and horizontal defect fill, PD, and CAL at 3 and 6 months compared to presurgical values. The difference determined for the PD values of both groups at a statistically significant degree in favor of grafted sites was maintained at all observation periods. No foreign body reaction was observed in PDL grafts. These short-term results point to the potential of PDL grafts in promoting healing of furcation lesions. This preliminary study suggests that the use of PDL grafts may have beneficial effects in the treatment of furcation defects.

New regenerative technologies: rationale and potential for periodontal regeneration: 2. Growth factors.

Regenerative techniques have been clinically available for over a decade, although success in promoting new bone, cementum and connective tissue attachment has been limited. New understanding of the tissues involved in regeneration, and of the materials used to promote regeneration, have led to new advances. This is the second of two articles discussing new regenerative technologies with respect to their rationale and potential for periodontal regeneration. This article focuses on growth factors, and in particular bone morphogenetic proteins.

New regenerative technologies: rationale and potential for periodontal regeneration: 1. New advances in established regenerative strategies.

Regenerative techniques have been clinically available for over a decade, but with limited success in promoting new bone, cementum and connective tissue attachment. New understanding of the tissues involved in regeneration and of the materials used to promote regeneration have led to new advances. This is the first of two articles that discusses new regenerative technologies with respect to their rationale and potential for periodontal regeneration and focuses on root conditioning, bone grafts and bone substitutes, and guided tissue regeneration.