Autologous Dental Pulp Stem Cells Research Articles

Management of endo-perio lesion with autologous stem cell therapy

The objective of periodontal therapy is the regeneration of tooth-supporting tissues. Various treatment modalities, such as the use of bone grafting materials, guided tissue regeneration, and delivery of enamel matrix derivatives or growth factors, are applied with large variability in regenerative outcomes. However, a case report was done by utilization of autologous dental pulp stem cells and periodontal ligament stem cell niches in the treatment of bone loss associated with endodontically and periodontally involved teeth. An autologous periodontal ligament stem cells niche adherent to the root and dental pulpal stem cells from dental pulp directly into the selected osseous defect following extraction of the impacted tooth in the same patient. The results of this case reported that the dental pulpal stem cells and periodontal ligament stem cells niche with gelatin sponge resulted in a significant amount of bone fill and reduction in probing pocket depth.

Pulp Regenerative Therapy Using Autologous Dental Pulp Stem Cells in a Mature Tooth with Apical Periodontitis: A Case Report

The utility and feasibility of pulp regenerative therapy with autologous dental pulp stem cells (DPSCs) in mature teeth with irreversible pulpitis were clinically demonstrated. On the other hand, there is no evidence of the utility of DPSCs in mature teeth with apical periodontitis. The aim of this case report was to describe the potential utility of regenerative cell therapy in mature teeth with apical periodontitis. A 44-year-old man was referred for pulp regeneration due to a periapical lesion in his maxillary first premolar. Root canal disinfection was performed by irrigation and intracanal medication by nanobubbles with levofloxacin and amphotericin B in addition to conventional irrigation. Autologous DPSCs isolated from an extracted third molar were transplanted into the root canal after residual bacteria and fungi were below the detection level by polymerase chain reaction assay using universal genes to amplify specific regions within bacterial 16S ribosomal DNA and fungal ribosomal DNA (ITS1), respectively. There were no adverse events or systemic toxicity assessed for clinical evaluations during the 79-week-follow-up period and laboratory evaluations after 4 weeks. The affected tooth was responsive to the electric pulp test. Cone-beam computed tomographic imaging revealed a reduced lesion size, remission of the periapical tissue, and mineralized tissue formation in the apical part of the canal after 79 weeks. The signal intensity on magnetic resonance imaging of the regenerated tissue in the affected tooth was comparable to that of the normal pulp in the adjacent teeth after 24 weeks. This case report demonstrated the potential use of DPSCs for pulp regenerative therapy in mature teeth with apical periodontitis.

Pulp Regenerative Cell Therapy for Mature Molars: A Report of 2 Cases

Regenerative cell therapy using autologous dental pulp stem cells (DPSCs) in mature single-rooted teeth is a potential alternative to traditional endodontic treatment. However, there is no evidence supporting the use of DPSCs in multirooted teeth. This case report aimed to demonstrate the feasibility and outcomes of pulp regenerative cell therapy in mature multirooted molars, which typically have a higher prevalence of apical deltas. A 26-year-old male and a 29-year-old male were referred for the pulp regeneration of their maxillary molars. After access preparation and establishing apical patency, root canal preparation and disinfection were performed. Autologous DPSCs were isolated from extracted third molars, cultured according to the guidelines of good manufacturing practice, and transplanted into the prepared root canals with granulocyte colony-stimulating factor in atelocollagen. The access cavity was sealed with Biodentine and composite resin. Clinical evaluation during the follow-up period of 48 weeks and laboratory evaluation after 4 weeks revealed no adverse events or evidence of systemic toxicity. After 48 weeks, radiographs and cone-beam computed tomography showed no periapical radiolucency. The teeth showed a positive response to electric pulp testing in 4 weeks in both cases. The signal intensities on magnetic resonance imaging of the regenerated pulp tissue in the affected teeth were comparable to those of the normal pulp in adjacent teeth after 24 weeks. This report of 2 cases demonstrates the utility of DPSCs and the feasibility of pulp regenerative cell therapy in multirooted molars.

Effects of autologous dental pulp stem cells and mineral trioxide aggregate on exposed dogs’ dental pulp

This study evaluated exposed dogs’ dental pulp response after direct capping with autologous dental pulp stem cells (DPSCs) and compared the results with MTA (Angelus, Brazil). Sixty teeth from six mongrel dogs were included (n = 60), allocated into four groups; negative control (n = 6), positive control (n = 6), MTA (n = 24), and DPSCs (n = 24). DPSCs were isolated and cultured from extracted first premolars (1premolar/dog). The teeth were prepared for histological and immunohistochemical analyses. Statistical analysis was calculated using ANOVA tests, P ≤ 0.05. MTA induced the formation of an almost complete calcific bridge. DPSCs successfully regenerated the injured pulp and dentin. The comparison between the capping groups and time intervals had a statistically significant effect, as well as, the interaction between the two variables. DPSCs had greater ability in the reparative and regenerative process of dentin and odontoblastic differentiation by having a significantly stronger TGFβ1 expression than MTA.

Human intrabony defect regeneration with micrografts containing dental pulp stem cells: A randomized controlled clinical trial.

The goal of this study was to evaluate if dental pulp stem cells (DPSCs) delivered into intrabony defects in a collagen scaffold would enhance the clinical and radiographic parameters of periodontal regeneration. In this randomized controlled trial, 29 chronic periodontitis patients presenting one deep intrabony defect and requiring extraction of one vital tooth were consecutively enrolled. Defects were randomly assigned to test or control treatments which both consisted of the use of minimally invasive surgical technique. The dental pulp of the extracted tooth was mechanically dissociated to obtain micrografts rich in autologous DPSCs. Test sites (n=15) were filled with micrografts seeded onto collagen sponge, whereas control sites (n=14) with collagen sponge alone. Clinical and radiographic parameters were recorded at baseline, 6 and 12months postoperatively. Test sites exhibited significantly more probing depth (PD) reduction (4.9mm versus 3.4mm), clinical attachment level (CAL) gain (4.5 versus 2.9mm) and bone defect fill (3.9 versus 1.6mm) than controls. Moreover, residual PD<5mm (93% versus 50%) and CAL gain ≥4mm (73% versus 29%) were significantly more frequent in the test group. Application of DPSCs significantly improved clinical parameters of periodontal regeneration 1year after treatment.

Tissue Engineering of Necrotic Dental Pulp of Immature Teeth with Apical Periodontitis in Dogs: Radiographic and Histological Evaluation.

To evaluate tissue engineering technology to regenerate pulp-dentin like tissues in pulp canals of immature necrotic permanent teeth with apical periodontitis in dogs. The study was performed on 36 teeth in 12 dogs. The experiment was carried out using split mouth design. In each dog 3 teeth were selected for implementing the study procedure. Apical periodontitis was induced in Group A and B teeth. Group (A): immature upper left 2nd permanent incisors that were transplanted with a construct of autologous dental pulp stem cells with growth factors seeded in a chitosn hydrogel scaffold. Group (B): immature upper right 2nd permanent incisor that received only growth factors with scaffold. A third tooth in each dog was selected randomly for isolation of dental pulp stem cells (DPSCs). Both groups were closed with a double coronal seal of white MTA (Mineral trioxide aggregate) and glass ionomer cement. Both groups were monitored radiographically for 4 months and histologically after sacrificing the animals. There was no statistically significant difference in radiographic findings between group (A) and group (B) for healing of radiolucencies, while there was statistically significant difference between group (A) and group (B) regarding radicular thickening, root lengthening and apical closure. Histologically, group (A) teeth showed regeneration of pulp- dentin like tissue while group (B) teeth did not show any tissue regeneration. Dental pulp stem cells and growth factors incorporated in chitosan hydrogel are able to regenerate pulp- dentine like tissue and help in complete root maturation of non-vital immature permanent teeth with apical periodontitis in dogs.

Immunohistochemical and Histochemical Analysis of Newly Formed Tissues in Root Canal Space Transplanted with Dental Pulp Stem Cells Plus Platelet-rich Plasma

IntroductionTissue regeneration in root canals after pulpectomy can be achieved by transplantation of autologous dental pulp stem cells and/or platelet-rich plasma. However, the identity of the newly formed tissue in the pulp space has been only examined by histologic analysis. This study aimed to apply immunohistochemistry and histochemistry to detect specific markers in the newly generated tissues after root canal regenerative treatment. MethodsIn our previous study, 32 root canals in 4 mature dogs were treated with a pulp regeneration procedure after pulpectomy using either blood clot, transplantation of dental pulp stem cells, platelet-rich plasma, or a combination of cells and plasma. In the present study, the tissues were examined for the expression of periostin to detect periodontal ligament tissue, nestin and dentin sialoprotein for odontoblasts, and bone sialoprotein and osteocalcin for bone tissues. Samples were also stained for tartrate-resistant acid phosphatase (TRAP) as a marker for osteoclastic lineages. ResultsContinuous periostin-positive tissue was observed extending from the periodontal ligament into the inner canal surface in which the mineral islands were surrounded by weak periostin staining. There was also positive staining for TRAP, bone sialoprotein, and osteocalcin in the canal space, suggesting the presence of bone tissue. A layer of mineralized tissue along the inner surface of the root canal was negative for TRAP, suggesting the tissue likely to be cementum. In all samples, no nestin-positive reaction was observed, whereas dentin sialoprotein was detected in PDL, dentinal tubules, and intracanal fibrous tissues. There was no difference between any of the 4 groups. ConclusionsThe tissues formed in the dog mature root canals after regenerative endodontic procedures are not pulp tissues but mainly periodontal tissues.

Preliminary Study on Dental Pulp Stem Cell–mediated Pulp Regeneration in Canine Immature Permanent Teeth

IntroductionThe health of human teeth depends on the integrity of the hard tissue and the activity of the pulp and periodontal tissues, which are responsible for nutritional supply. Without the nourishing of the pulp tissue, the possibility of tooth fracture can increase. In immature permanent teeth, root development may be influenced as well. This study explored the potential of using autologous dental pulp stem cells (DPSCs) to achieve pulp regeneration in a canine pulpless model. MethodsThe establishment of the pulpless animal model involved pulp extirpation and root canal preparation of young permanent incisor teeth in beagles. Autologous DPSCs were obtained from extracted first molars and expanded ex vivo to obtain a larger number of cells. The biological characteristics of canine DPSCs (cDPSCs) were analyzed both in vitro and in vivo by using the same method as used in human DPSCs. cDPSCs were transplanted into the pulpless root canal with Gelfoam as the scaffold, and root development was evaluated by radiographic and histologic analyses. ResultscDPSCs with rapid proliferation, multiple differentiation capacity, and development potential were successfully isolated and identified both in vitro and in vivo. After they were transplanted into the pulpless root canal with Gelfoam as the scaffold, DPSCs were capable of generating pulp-like tissues containing blood vessels and dentin-like tissue. Thickening of the root canal wall was also observed. ConclusionsThis study demonstrates the feasibility of using stem cell–mediated tissue engineering to realize pulp regeneration in immature teeth.

Autologous Dental Pulp Stem Cells in Regeneration of Defect Created in Canine Periodontal Tissue

This study aimed to investigate effects of dental pulp stem cells (DPSCs) on regeneration of a defect experimentally created in the periodontium of a canine model. Surgically created mesial 3-walled periodontal defects with ligature-induced periodontitis were produced bilaterally in the first lower premolar teeth of 10 mongrel dogs. Simultaneously, DPSCs were derived from the maxillary premolar teeth of the same dogs. Four weeks after creation of the periodontitis model, autologous passaged-3 DPSCs combined with Bio-Oss were implanted on one side as the test group. On the other side, only Bio-Oss was implanted as a control. Eight weeks after surgery, regeneration of the periodontal defects was evaluated histologically and histomorphometrically in terms of bone, periodontal ligament (PDL), and cement formation. Histologically, in all test specimens (10 defects), regeneration of cementum, bone, and PDL was observed. In the control groups, although we observed the regeneration of bone in all defects, the formation of cementum was seen in 9 defects and PDL was seen in 8 defects. Histomorphometric analyses showed that the amount of regenerated cementum and PDL in the test groups (3.83 ± 1.32 mm and 3.30 ± 1.12 mm, respectively) was significantly higher than that of the control groups (2.42 ± 1.40 mm and 1.77 ± 1.27 mm, respectively; P < .05). A biocomplex consisting of DPSCs and Bio-Oss would be promising in regeneration of periodontal tissues.

Autologous Dental Pulp Stem Cells in Regeneration of Defect Created in Canine Periodontal Tissue

Autologous Dental Pulp Stem Cells in Regeneration of Defect Created in Canine Periodontal Tissue

Reconstruction of Alveolar Bone Defects Using Bone Morphogenetic Protein 2 Mediated Rabbit Dental Pulp Stem Cells Seeded on Nano-Hydroxyapatite/Collagen/Poly(L-lactide)

The objective of the present study was to evaluate the capacity of a tissue-engineered bone complex of recombinant human bone morphogenetic protein 2 (rhBMP-2)-mediated dental pulp stem cells (DPSCs) and nano-hydroxyapatite/collagen/poly(L-lactide) (nHAC/PLA) to reconstruct critical-size alveolar bone defects in New Zealand rabbit. Autologous DPSCs were isolated from rabbit dental pulp tissue and expanded ex vivo to enrich DPSCs numbers, and then their attachment and differentiation capability were evaluated when cultured on the culture plate or nHAC/PLA. The alveolar bone defects were treated with nHAC/PLA, nHAC/PLA+rhBMP-2, nHAC/PLA+DPSCs, nHAC/PLA+DPSCs+rhBMP-2, and autogenous bone (AB) obtained from iliac bone or were left untreated as a control. X-ray and a polychrome sequential fluorescent labeling were performed postoperatively and the animals were sacrificed 12 weeks after operation for histological observation and histomorphometric analysis. Our results showed that DPSCs expressed STRO-1 and vementin, and favored osteogenesis and adipogenesis in conditioned media. DPSCs attached and spread well, and retained their osteogenic phenotypes on nHAC/PLA. The rhBMP-2 could significantly increase protein content, alkaline phosphatase activity/protein, osteocalcin content, and mineral formation of DPSCs cultured on nHAC/PLA. The X-ray graph, the fluorescent, histological observation, and histomorphometric analysis showed that the nHAC/PLA+DPSCs+rhBMP-2 tissue-engineered bone complex had an earlier mineralization and more bone formation inside the scaffold than nHAC/PLA, nHAC/PLA+rhBMP-2, and nHAC/PLA+DPSCs, or even autologous bone. Implanted DPSCs' contribution to new bone was detected through transfected eGFP genes. Our findings indicated that stem cells existed in adult rabbit dental pulp tissue. The rhBMP-2 promoted osteogenic capability of DPSCs as a potential cell source for periodontal bone regeneration. The nHAC/PLA could serve as a good scaffold for autologous DPSC seeding, proliferation, and differentiation. The tissue-engineered bone complex with nHAC/PLA, rhBMP-2, and autologous DPSCs might be a better alternative to autologous bone for the clinical reconstruction of periodontal bone defects.

Dental Stem Cell Therapy with Calcium Hydroxide in Dental Pulp Capping

Calcium hydroxide has been extensively and steadily used for direct pulp capping in modern clinical dentistry. As it was known to have potential to induce hard tissue repair, this chemical has been applied to the exposed dental pulp and the hard tissue is expected to be regenerated above the pulp. During the reparative process of exposed pulp, primary odontoblasts that were lost as a result of extensive damage are replaced with newly differentiated odontoblast-like cells. This process is known to follow the sequential steps of proliferation, migration, and differentiation of progenitor cells. This research will examine the relationship between calcium hydroxide and the recruitment, proliferation, and mineralization of postnatal dental stem cells, obtained from an immature dental tissue of beagle dogs. Immunocytochemical staining and reverse transcriptase-polymerase chain reaction were used to identify the putative stem cell markers. Immunoblot analysis, wound healing assay, cell migration assay, and alizarin red staining were used to evaluate proliferation, migration, and mineralization capacity of the calcium hydroxide-treated stem cells. As an in vivo study, a combination of calcium hydroxide and autologous dental pulp stem cells (DPSCs) was applied for the treatment of intentionally created tooth defects on the premolars and the molars in beagle dogs to observe dentin regeneration. Ex vivo expanded DPSCs and periodontal ligament stem cells expressed STRO-1 and CD146, the mesenchymal stem cell markers. It was evident that calcium hydroxide increased recruitment, migration, proliferation, and mineralization of the DPSCs and periodontal ligament stem cells. Such results are valuable for future availability of DPSCs, which are recently focused as the stem cell reservoir for regeneration of dentin upon tooth injury, as well as for elucidation of the role of calcium hydroxide in pulp capping therapy.