The applications of the plasma matrix in the treatments of dental pulp and periapical diseases / 口腔疾病防治

@#The plasma matrix is a kind of autologous blood conduct. It has been widely used in maxillofacial tissue regeneration, skin cosmetology and some other fields. Recently, to preserve the dental pulp as well as the teeth, pulp regeneration therapy and apical surgery have become increasingly important as well as the applications of bioactive materials. As a kind of autologous bioactive material, the plasma matrix has some natural advantages as it is easy to obtain and malleable. The plasma matrix can be used in the following cases: ①pulp revascularization of young permanent teeth with open apical foramina that cannot stimulate apical bleeding; ② apical barrier surgery with bone defects and large area perforation repair with bone defects or root sidewall repair surgery; ③ apical surgeries of teeth with large area of apical lesions, with or without periodontal diseases. The plasma matrix is a product derived from our blood, and there are no obvious contraindications for its use. Several systematic reviews have shown that the plasma matrix can effectively promote the regenerative repair of dental pulp in patients with periapical diseases. However, the applications of plasma matrix are different because its characteristics are affected by different preparation methods. In addition, there is still a lack of long-term clinical researches on the plasma matrix, and the histological evidences are difficult to obtain, so a large number of in vitro and in vivo experimental studies are still needed. This article will describe the applications of different kinds of plasma matrix for dental pulp regeneration and bone tissue regeneration in apical surgeries to provide references for clinicians in indication selection and prognosis evaluation.

Research progress of the application of peptide hydrogel in the revascularization of pulp regeneration / 国际生物医学工程杂志

In recent years, problems such as the devitalization of dental pulp and the increased brittleness and fragility of teeth after root canal treatment have attracted more and more attention. Therefore, pulp regeneration has become the focus of research in endodontics and periapical disease, in which vascularization is of paramount importance. It is found that peptide hydrogel scaffolds have been widely applied because of their properties of impacting cell behavior, promoting angiogenesis, and being adaptable. In this review paper, the research progress of the application of peptide hydrogel in the vascularization of pulp regeneration and the properties of various peptide hydrogels were summarized to provide a reference for the further application of peptide hydrogel in pulp regeneration.

Effect of stem cell factor on the angiogenic ability of cocultured DPSCs and HUVECs / 口腔疾病防治

Objective@#To study the effect of stem cell factor (SCF) on the angiogenic ability of cocultured dental pulp stem cells (DPSCs) and human umbilical vein endothelial cells (HUVECs).@*Methods @#This study has been reviewed and approved by the Ethics Committee. The experiment was split into the HUVECs, SCF+HUVECs, DPSCs+HUVECs, and SCF+DPSCs+HUVECs groups. A mixture of SCF and culture medium was used to prepare a mixed culture medium with an SCF concentration of 100 ng/mL. In vitro coculture of DPSCs and HUVECs was performed at a 1∶5 ratio. CCK-8 proliferation assay was used to observe the proliferative capacity of cells in each group on days 1, 3, 5, and 7. Wound healing and Transwell migration assays were used to detect the effect of SCF on cell migration under either direct or indirect coculture conditions, respectively. In vitro angiogenesis experiments were performed to detect the angiogenic capacity of the cells in each group. The vascular endothelial growth factor A (VEGFA) concentration in the cell culture supernatant was detected using ELISAs, and the protein expression levels of CD31, CD34, and VEGFA were detected using Western blot analysis. @*Results @# Wound healing and Transwell migration experiments showed that SCF significantly promoted the migration of cocultured DPSCs and HUVECs (P<0.05). The in vitro angiogenesis experiment showed that the number of branches and the total length of branches of tubular structures in the SCF+DPSCs+HUVECs group were significantly greater than those of the other groups (P<0.05), and the expression levels of the vascular-related proteins CD31, CD34, and VEGFA in this group were greater (P<0.01). @*Conclusion @# SCF can enhance the migration and in vitro angiogenesis of cocultured DPSCs and HUVECs.

Advances in the study on cytokines related to dental pulp regeneration / 口腔医学

@#With the development of molecular biology, biomaterials and tissue engineering, regenerative treatment of pulpal and periradicular diseases is facing new opportunities. At present, a large number of studies on dental pulp regeneration reveal that cytokines are essential for promoting migration, proliferation and osteogenic differentiation of dental pulp stem cells. In this paper, we review several kinds of cytokines related to dental pulp regeneration, and analyze their roles and regulatory mechanisms in dental pulp regeneration.

Decoloración coronaria inducida por la utilización de Biodentine y MTA blanco en procedimientos de regeneración pulpar: estudio ex vivo / Coronal discoloration induced by the use of Biodentine and white MTA in pulp regeneration procedures: an ex-vivo study

Se comparó el grado de decoloración de la corona clínica en piezas dentarias anteriores humanas ex-traídas, sometidas a procedimientos de regeneración endodóntica, utilizando MTA blanco o sustituto bioac-tivo de la dentina (Biodentine) como barrera cervical, en presencia de coágulo sanguíneo como andamio. En total se prepararon 24 piezas dentarias anterio-res superiores humanas que fueron divididas en dos grupos control (GC) y dos grupos experimentales (GE). Cada uno incluía 6 piezas dentarias. En los GE se colo-có sangre humana fresca en el interior del conducto, y se confeccionó una barrera de Biodentine (GE3) o MTA (GE4). En los GC se colocó una torunda de algo-dón estéril saturada con solución fisiológica estéril, y se confeccionó una barrera de Biodentine (GC1) o MTA (GC2). El color se evaluó de acuerdo con el espa-cio de color CIE L* a* b* utilizando imágenes fotográfi-cas digitales estandarizadas en dos puntos de tiempo: día 0 (T0) y día 35 (T35). La descripción de los datos in-cluyó mediana (Md), primer cuartil (Q1), tercer cuartil (Q3), media y desviación estándar (DE). Se emplea-ron las pruebas de los rangos con signo de Wilcoxon (RSW) y ANOVA de una vía; p < 0,05 fue considerado significativo. Cuando se comparó ∆E se observaron diferencias significativas entre GC1 y el resto de los materiales (p < 0,05). ∆E fue menor en GC1 (media ± DE; 2,1 ± 1,6) que en los grupos restantes que no pre-sentaron diferencias significativas entre sí. En base a estos resultados, la estabilización del coágulo san-guíneo, como así la limpieza de la cavidad previa a la colocación del Biodentine y el uso de barreras cervi-cales, es imprescindible para evitar la coloración de la corona clínica (AU)

Discoloration remains an unfavorable complication of otherwise successful regenerative endodontic procedure of immature teeth with necrotic pulp. Objective: Compare the degree of discoloration of extracted human teeth after regenerative endodontic procedures, using MTA or Biodentine as a cervical barrier with a blood clot as a scaffold. In total 24 human upper anterior teeth were prepared and divided into two control groups (CG) and two experimental groups (EG). In the EG, fresh human blood was placed inside the root and a Biodentine (GE3) or MTA (GE4) barrier was made in. A sterile cotton swab saturated with sterile physiological solution was placed in the GCs and a Biodentine (GC1) or MTA (GC2) barrier was made in. The color was evaluated according to the CIE L* a* b* color space using standardized digital photographic images at two time points: day 0 (T0) and day 35 (T35). The description of the data included median (Md), first quartile (Q1), third quartile (Q3), means, and standard deviation (SD). Wilcoxon signed rank tests (RSW) and one-way ANOVA were used. p < 0.05 was considered significant. When ∆E was compared, significant differences were observed between GC1 and the rest of the materials (p < 0.05). ∆E was lower in CG1 (mean ± SD; 2.1 ± 1.6) than in the remaining groups, which did not present significant differences between them. There was no significant difference between tooth discolorations with materials in the presence of blood. However, in the absence of blood, Biodentine exhibited less tooth discoloration than MTA (AU)

Effects of N-cadherin silencing on the proliferation and migration of human dental pulp stem cells / 口腔疾病防治

Objective @#To investigate the effects of N-cadherin silencing on the proliferation and migration of human dental pulp stem cells (DPSCs) and to provide experimental evidence for DPSCs-based dental pulp regeneration.@* Methods@# DPSCs were transfected with N-cadherin shRNA lentivirus, and the knockdown efficiency of N-cadherin at both the mRNA and protein levels was confirmed by qRT-PCR and Western blot. The experiment included a negative control group (shRNA -NC) and an N-cadherin shRNA silencing group. Cell proliferation was detected by the CCK-8 method. Cell cycle and apoptosis were assessed by flow cytometry, and cell migration was detected using the Transwell method.@*Results@#N-cadherin shRNA significantly reduced the expression levels of N-cadherin mRNA and protein in DPSCs (P<0.001). The proliferation activity of the N-cadherin shRNA group was significantly greater than that of the shRNA-NC group on the 3rd and 4th days after cell inoculation and lower than that of the shRNA-NC group from the 6th to 8th days (P<0.05). On the 3rd day after cell inoculation, the proportion of cells in S phase and G2 phase in the N-cadherin shRNA group was greater than that in the shRNA-NC group (P<0.05). On the 6th day after cell inoculation, the proportion of cells in S phase and G2 phase in the N-cadherin shRNA group was lower than that in the shRNA-NC group (P<0.05), and the proportion of apoptotic cells in the N-cadherin shRNA group was greater than that in the shRNA-NC group (P<0.01). Low densities cells and high densities cells were inoculated into Transwell upper chamber for 20 h, the number of cells passing through the membrane pores of upper chamber in the N-cadherin shRNA group was greater than that in the shRNA-NC group (P<0.001).@*Conclusion@#Silencing N-cadherin expression can promote the early proliferation and migration of DPSCs.

Research progress on injectable hydrogel scaffolds in dental pulp regeneration / 口腔疾病防治

@#Tissue engineering provides a new possibility for pulp regeneration. As one of the three elements of tissue engineering, scaffolds have attracted increasing attention. Because the root canal system is limited by the unique anatomical structure of the long and narrow lumen, the preformed scaffold cannot be completely covered with the whole root canal space, although it is convenient to apply, so the injectable scaffold may be an ideal choice for pulp tissue engineering. Hydrogels are hydrophilic polymer networks with physical properties similar to soft tissues. They can provide a porous hydrophilic microenvironment, which facilitates the diffusion of oxygen and nutrients. In recent years, researchers have used injectable hydrogels with different mechanical properties and/or loaded biologically active ingredients as scaffolds to promote revascularization and the regeneration of pulp. The results show that natural polymer hydrogels, synthetic polymer hydrogels, and composite hydrogels combining natural and synthetic polymers all have excellent biocompatibility. The types and mechanical properties of hydrogels and the addition of bioactive ingredients can influence the behavior of stem cells, and gelatin-based hydrogels and fibrin-based hydrogels can also achieve rapid vascularization, which creates the conditions for the formation of pulp-like tissues. Among them, photocrosslinked methacrylated gelatin/hyaluronic acid hydrogels, two/multicomponent hydrogels combined with chitosan with antibacterial and temperature-sensitive properties and new self-assembled peptides have become major research topics in recent years due to their excellent properties. To develop suitable hydrogel scaffolds and promote their application in pulp regeneration, this article reviews the research progress in the types, preparation, and application of injectable hydrogels used for dental pulp regeneration.

Application of poly(lactic-co-glycolic acid) in the treatment of pulp diseases / 口腔疾病防治

@#The development of materials science is of great significance to the treatment of dental pulp diseases. Poly lactic acid glycolic acid (PLGA) copolymer is an organic macromolecule compound that is widely used in the preparation of biomedical materials. In recent years, PLGA, as a drug/molecular loaded system and tissue regeneration scaffold, has shown prospects for application in the treatment of dental pulp diseases. This paper will review the application of PLGA in the treatment of dental pulp diseases and provide a basis for its further development and utilization. The results of the literature review show that PLGA is a drug/molecular delivery system that is mainly used in the improvement of pulp capping materials, root canal disinfectant and apexification materials. PLGA-improved pulp capping agents can prolong the action time of the drug and reduce toxicity. The modified root canal disinfectant can realize the sustained release of drug, make the drug penetrate deeper into the subtle structure, and contact more widely with the pathogenic bacteria. The modified apexification materials can provide more convenient administration methods for apexifixment. As a scaffold for tissue engineering, PLGA is mainly used in the study of pulp regeneration. The optimization of PLGA physical properties and action environment can provide a more suitable microenvironment for seed cells to proliferate and differentiate. How to utilize the advantages of PLGA to develop a more suitable material for endodontic application needs further study.

Research on the color stability of Biodentine and MTA within the blood environment / 口腔疾病防治

Objective@#To compare the color stability of Biodentine and mineral trioxide aggregate (MTA) within the blood environment in vitro and to further investigate the underlying reasons for such color instability. @*Methods @#We first generated Biodentine and MTA discs with a diameter of 5 mm and a height of 3 mm. 24 discs of each material were randomly divided into two groups: the deionized water group and the defibrinated sheep blood group. Discs of each group were immersed for 1 day or 7 days before assessments. First, all discs were photographed to directly compare the discoloration of Biodentine and MTA. The color degree of the two materials was tested by a spectrophotometer. Then, the high-resolution morphological characteristics were observed by scanning electron microscopy. Finally, the chemical contents of each element in the material were measured by energy-dispersive spectroscopy.@*Results @#Compared to immediately after stripping, a change in the brightness of discs after immersion in defibrinated sheep blood for 1 day was observed only in MTA. On the 7th day after being immersed in blood, the colors of both the Biodentine and MTA discs darkened and turned deep red, but the darkness of the MTA discs increased significantly. The color change of MTA immersed in blood was measured on a spectrophotometer with a greater 7-day ∆E (21.257 ± 0.955) than the Biodentine 7-day ∆E (5.833 ± 0.501) (t=24.781, P < 0.001). MTA exhibits more discoloration as the immersion time goes on. A significant difference was noted between the 1-day ∆E(6.233 ± 0.888) and the 7-day ∆E(t=19.956, P < 0.001) of MTA immersed in blood. However, there was no statistically significant difference between the 1-day ∆E (6.790 ± 0.831) and the 7-day ∆E(t=1.707, P=0.163) of Biodentine immersed in blood. It was observed by scanning electron microscopy that after 7 days of immersion in the defibrinated sheep ablood, the surface porosity of MTA was larger than that of Biodentine, and the crystal edge of MTA became rounded and blunt. The analysis by energy-dispersive X-ray spectroscopy showed that the oxygen content decreased and the bismuth content increased in MTA after immersion in defibrinated sheep blood for 7 days. Zirconium was not detected in Biodentine due to its low radiodensity, but the contents of other elements were stable in Biodentine after immersion in defibrinated sheep blood for 7 days. @* Conclusion@#The color stability of Biodentine within the blood environment is better than that of MTA in vitro, which is mainly related to the low surface porosity and stable composition of the anti-radiation agent of Biodentine.

Applications and prospects of 3D printing technology in pulp regeneration / 口腔疾病防治

@#In recent years, pulp regeneration has become a research hotspot in the field of stomatology. 3D printing can realize precise control of structure and shape of scaffolds, which provide basis for seed cell adhesion and growth factor release. The 3D printing "pulp complexes" constructed by 3D printing scaffolds for tissue engineering provides a new direction for pulp regeneration research. This paper reviews the applications of 3D printing technology in pulp regeneration. The results of literature review showed that the scaffold materials, seed cells and growth factors in the 3D printing "pulp complexes" all play an important role in the pulp regeneration research. Among them, the scaffold materials act as carriers to load seed cells and growth factors and provide a suitable microenvironment for them. The common seed cells such as dental pulp stem cells, stem cells from apical papilla and stem cells from the human pulp of exfoliated deciduous teeth can provide the cellular basis for pulp regeneration. Moreover, the introduction of growth factors can further support the differentiation of pulp tissue and the reconstruction of pulp vessels and promote pulp regeneration. At present, the 3D printing "pulp complexes" in the study of dental pulp regeneration has made some progress and can induce the formation of pulp-like tissues in the laboratory. However, preparing 3D-printing "pulp complex" with good biological activity, which integrates biomimetic blood vessels and nerves to supply oxygen and nutrients to the cells in the root canal, remains a huge challenge and still needs further exploration and research.

Research progress indental pulp tissue engineering scaffolds / 国际生物医学工程杂志

Pulp necrosis can cause increased tooth fragility and easy fracture, and hinder the sustainable development of young permanent teeth. Therefore, pulp regeneration therapy has important clinical significance. However, due to the complicated and varied anatomical structure of the pulp tissue, and various components such as nerves and blood vessels, there are many challenges in dental pulp regeneration strategy. In this paper, the recent research progress in the application of dental pulp tissue construction and transplantation by tissue engineering method was reviewed, and the selection of suitable scaffold materials and the construction of dental pulp tissue were discussed. The functional characteristics of scaffold materials were described,such as sodium alginate, chitosan, hyaluronic acid, collagen, gelatin, fibrous protein, silk fibroin, peptides and self-assembled peptides, polylactic acid, polyglycolic acid and their copolymers. In addition, the functions and characteristics of these materials were briefly introduced, as well as the functional modification with growth factors and other biological matrix extract involvement, and functional improvement of the composite scaffolds with complementary effects.Combined with the requirements of clinical operability, the composition design and functional characteristics of the injectable hydrogel scaffolds consisted of hydrophilic composite materials and/or modified with hydrophilic groups were also discussed.This review paper would be useful in providing some reference for the future research and exploration of dental pulp regeneration.

Factors affecting the secretion of vascular endothelial growth factor from dental pulp stem cells / 中国组织工程研究

BACKGROUND: How to regulate the secretion of vascular endothelial growth factor from dental pulp stem cells is of great significance for promoting dental pulp regeneration by dental pulp stem cells, especially promoting dentinogenesis, dental pulp angiogenesis and neurogenesis. OBJECTIVE: To review the factors affecting the secretion of vascular endothelial growth factor from dental pulp stem cells, providing ideas for pulp regeneration and other clinical applications. METHODS: We searched the articles in PubMed, CNKI, WanFang databases with the keywords of “vascular endothelial growth factor; dental pulp stem cell; dental pulp regeneration; hypoxia; inflammatory mediator; bacterial virulence factor; growth factor; material” in Chinese and English, respectively. Finally, 56 articles met the criteria for review. RESULTS AND CONCLUSION: Vascular endothelial growth factor is the most important cytokine in angiogenesis and neovasculization, which promotes the proliferation and differentiation of stem cells as well as protecting nerves and promoting neurogenesis. Dental pulp stem cells are the most important stem cells in dental pulp tissues. They are also important seed cells in pulp regeneration. Dental pulp stem cells have biological characteristics such as high proliferation, self-renewal and multi-lineage differentiation, and have certain secretory activities, which can be used as an alternative source of exogenous vascular endothelial growth factor. A variety of factors, such as hypoxia, bacterial virulence factors, inflammatory factors, growth factors and materials, are associated with the cytokine secretion activity of dental pulp stem cells, which can affect the expression and secretion of vascular endothelial growth factor in dental pulp stem cells. Therefore, increasing concern has been emphasized on the regulation of vascular endothelial growth factor ecpression and secretion in dental pulp stem cells and the better use in pulp regeneration.

Role of angiogenesis in dental pulp regeneration: Exosomes and angiogenic factors / 中国组织工程研究

BACKGROUND: With the application of tissue engineering technology In the field of stomatology, It Is possible to construct a tissue-engineered dental pulp for the regeneration of dentin-pulp complex. Formation of new blood supply system through angiogenesis Is mandatory to dental pulp regeneration. Angiogenesis is defined as the formation of new blood vessels from preexisting capillaries, which has great significance in pulp regeneration and homeostasis. OBJECTIVE: To review the contribution of exosomes and angiogenic factors to angiogenesis in the dental pulp. METHODS: A search of PubMed and CNKI was performed for relevant literature published from 2017 through 2019. The search terms were "tissue engineering, pulp regeneration, regenerative endodontics, angiogenesis, neovascularization, angiogenic, signal molecules, exosomes, factors, role, mechanism" In English and Chinese, respectively. RESULTS AND CONCLUSION: Many studies have indicated an intimate relationship between angiogenesis and dental pulp regeneration. The contribution of exosomes and angiogenic factors to angiogenesis of the dental pulp has been previously discussed. Angiogenesis is an indispensable process during dental pulp regeneration. The survival of transplanted pulp tissue is closely linked to the process of angiogenesis at sites of application. However, further Investigations are warranted on the detailed regulatory mechanisms of exosomes and factors Involved In Initiation and progression of angiogenesis In pulp tissue.

Scaffolds for dental pulp regeneration and revascularization / 中国组织工程研究

BACKGROUND: Rapid development in tissue engineering research and technology makes dental pulp regeneration and revascularization possible. The interactions of stem cells, scaffolds and signaling factors in tissue engineering are particularly important. Whether stem cells can proliferate, differentiate and develop dental pulp-like tissue greatly depends on the choice of scaffolds OBJECTIVE: To review the widely studied and effective scaffold materials and two methods of scaffold preparation and analyze their applications in dental pulp reconstruction and their revascularization ability. METHODS: The first author searched PubMed, Wanfang and CNKI databases using a computer for relevant articles published between January 1, 2019 and September 30, 2019 with the search terms “pulp regeneration, pulp revascularization, scaffold” in English, and “pulp regeneration, pulp revascularization, revascularization, scaffold” in Chinese. A total of 421 English articles and 181 Chinese articles were retrieved. Finally, 61 articles were reviewed. RESULTS AND CONCLUSION: Platelet-derived scaffolds, extracellular-matrix-derived scaffolds, and self-assembling peptide take effect in pulp regeneration and revascularization. Composite materials combining natural and synthetic materials prepared by hydrogel and nanomaterial techniques exhibited advantages in cell proliferation, differentiation, migration, adherence, anti-inflammation, and factor delivery. The modified composite materials have a strong ability to promote vascularization. With the development of scaffold design and preparation technology based on hydrogels and nanomaterials, problems regarding insufficient scaffold source and unstable clinical effect will be solved in the future.

Research progress of scaffolds for promoting the vascularization of regenerated dental pulp / 口腔疾病防治

@#Endothelial regeneration is a research hotspot in the field of dental pulp. The regeneration of endodontic blood flow is the bottleneck of dental pulp regeneration, and the applied scaffold material is the key to revascularization. Stent materials were reviewed. The literature review Results show that, depending on the source of the stent material used for endodontic revascularization, there are mainly natural, synthetic and composite materials. The natural scaffold materials used for vascular regeneration include chitosan, hyaluronic acid, bacterial cellulose, and proanthocyanidin; artificial scaffold materials include hydrogel, cryogel, and electrospinning. The bionic composite scaffold system with a double-layer tubular structure is low immunogenicity and good biocompatibility. Studies on the scaffold materials of bionic extracellular matrix, such as injectable hydrogels/microspheres, have promoted the development of dental pulp regeneration, that is, uniformly distributed scaffold materials in the root canal promote the generation of pulp-like tissue; Whether dental pulp tissue can establish effective blood circulation through the apical foramen remains a great challenge.

Clinical management and prognosis evaluation of pulp regeneration therapy / 中华口腔医学杂志

Pulp regeneration in a tooth with pulp necrosis is the research hotspot in current clinical treatment of endodontic diseases. Up to now, the revascularization therapy, which is one of the regenerative endodontic treatment, and the most extensive and effective method in clinical practice, can partially achieve the goal of pulp regeneration and root development in young permanent immature teeth. In order to standardize the technique and improve the curative effect, this atticle discusses the indications, pre-treatment preparation, treatment procedure and the rapeutic evaluation of pulp revascularization therapy.

Dental stem cell and dental tissue regeneration / 医学前沿

The teeth are highly differentiated chewing organs formed by the development of tooth germ tissue located in the jaw and consist of the enamel, dentin, cementum, pulp, and periodontal tissue. Moreover, the teeth have a complicated regulatory mechanism, special histologic origin, diverse structure, and important function in mastication, articulation, and aesthetics. These characteristics, to a certain extent, greatly complicate the research in tooth regeneration. Recently, new ideas for tooth and tissue regeneration have begun to appear with rapid developments in the theories and technologies in tissue engineering. Numerous types of stem cells have been isolated from dental tissue, such as dental pulp stem cells (DPSCs), stem cells isolated from human pulp of exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSCs), stem cells from apical papilla (SCAPs), and dental follicle cells (DFCs). All these cells can regenerate the tissue of tooth. This review outlines the cell types and strategies of stem cell therapy applied in tooth regeneration, in order to provide theoretical basis for clinical treatments.

Research progress of pulpotomy and crown pulp regeneration / 口腔疾病防治

@#Crown pulp regeneration is a method to replace the pulp-capping agent with stem cells and scaffold structures, which are placed on the section of healthy root pulp tissue after pulpotomy to regenerate the pulp-dentin complex in the crown. This paper reviews the significance, physiological basis, application and challenges of crown pulp regeneration to provide new ideas for the study of pulp regeneration. The results of a literature review show that the combination of traditional pulpotomy, stem cell biology and tissue engineering, as well as the regeneration of crowns and pulp by using the tissue repair potential of healthy root pulp can effectively promote the regeneration of dentin and parts of pulp. In recent years, with the development of research on pulp regeneration, many challenges have been gradually revealed. It is necessary not only to select the treatment methods that can promote the proliferation and differentiation of dental pulp stem cells safely and effectively but also to continue to explore the scaffold materials suitable for the structural and functional diversity of the pulp chamber.

Evaluation of SDF-1 complex with CGF applied to canine dental-pulp-like tissue regeneration / 上海交通大学学报（医学版）

Objective: To evaluate the feasibility of immature permanent teeth pulp regeneration with a new method that utilizes the integration of concentrated growth factor (CGF) as a scaffold and stromal cell-derived factor-1 (SDF-1). Methods: Canine dental pulp cells (DPC) were isolated and cultured in vitro. Then the effects of SDF-1 and CGF were observed on DPC proliferation and differentiation. The pulpless model was established on the beagle’s immature incisors which were divided into four groups: natural pulp (A), empty cannel (B), CGF-filling (C) and SDF-1/CGF-filling (D). After 10 weeks, specimens were checked by imaging examination, RT-PCR and histological observation. Results: CGF extraction (CGFe) induced DPC proliferation while the combination of SDF-1 and CGFe enhanced this effect and also facilitated odontogenic and angiogenic differentiation of DPC. According to imaging examination, the apex growth of all four groups was in varying degrees. RT-PCR indicated the expressions of odontogenesis and angiogenesis related genes in group D were higher than those in group C. Besides, neonatal dentin and dental-pulp-like tissue were observed inside the canal of both group C and D, while only cementum-like tissue existed around root apex of group B. Conclusion:SDF-1 plays an important role in driving the process of pulp-like-tissue regeneration of immature permanent teeth by using CGF as an effective scaffold.

Dental Pulp Regeneration: Insights from Biological Processes / Regeneración pulpar: Perspectivas desde los procesos biológicos

Abstract One of the major approaches on dental research in this century is the development of biological strategies (tissue engineering) to regenerate/biomineralize lost dental tissues. During dentin- pulp regeneration, the interaction between stem cells, signaling molecules, biomaterials and the microenvironment in the periapical area drives the process for pulp tissue engineering. Understanding the signaling mechanisms and interactions involved with the biological process for the formation of a new tissue is essential. The knowledge of the micro-environment is the key for the application of tissue engineering. The present article is a short review of the current state of this topic, with the purpose of showing insights of pulp regeneration.

Resumen Actualmente la investigación en odontología se orienta al desarrollo de estrategias basadas en principios biológicos (ingeniería de tejidos) para la regeneración/biomineralización de estructuras dentales perdidas. El proceso de regeneración del complejo dentino-pulpar está guiado por la compleja interacción entre las células indiferenciadas de origen dental (DTSC), moléculas de señalización y biomateriales con el microambiente donde se va a restablecer. Es esencial comprender detalladamente, los mecanismos de señalización e interacciones involucradas en los procesos biológicos para la formación de un nuevo tejido, además de la identificación de los componentes presentes en los tejidos dentales implicados en este proceso (características del microambiente), ya que representan la base sobre la cual se debe emplear la ingeniería de tejidos. El presente articulo es una breve revisión del estado actual del tema, con el fin de entender el proceso de regeneración pulpar, basado en la comprensión de los fundamentos biológicos.