A tooth is a complex biological organ and consists of multiple tissues including the enamel, dentin, cementum and pulp. Tooth loss is the most common organ failure. Can a tooth be regenerated？ Can adult stem cells be...A tooth is a complex biological organ and consists of multiple tissues including the enamel, dentin, cementum and pulp. Tooth loss is the most common organ failure. Can a tooth be regenerated？ Can adult stem cells be orchestrated to regenerate tooth structures such as the enamel, dentin, cementum and dental pulp, or even an entire tooth？ If not, what are the therapeutically viable sources of stem cells for tooth regeneration？ Do stem cells necessarily need to be taken out of the body, and manipulated ex vivo before they are transplanted for tooth regeneration？ How can regenerated teeth be economically competitive with dental implants？ Would it be possible to make regenerated teeth affordable by a large segment of the population worldwide？ This review article explores existing and visionary approaches that address some of the above-mentioned questions. Tooth regeneration represents a revolution in stomatology as a shift in the paradigm from repair to regeneration： repair is by metal or artificial materials whereas regeneration is by biological restoration. Tooth regeneration is an extension of the concepts in the broad field of regenerative medicine to restore a tissue defect to its original form and function by biological substitutes.展开更多
Background The seed cell is a core problem in bone tissue engineering research. Recent research indicates that human dental pulp stem cells （hDPSCs） can differentiate into osteoblasts in vitro, which suggests that t...Background The seed cell is a core problem in bone tissue engineering research. Recent research indicates that human dental pulp stem cells （hDPSCs） can differentiate into osteoblasts in vitro, which suggests that they may become a new kind of seed cells for bone tissue engineering. The aim of this study was to evaluate the osteogenic differentiation of hDPSCs in vitro and bone-like tissue formation when transplanted with three-dimensional gelatin scaffolds in vivo, and hDPSCs may become appropriate seed cells for bone tissue engineering. Methods We have utilized enzymatic digestion to obtain hDPSCs from dental pulp tissue extracted during orthodontic treatment. After culturing and expansion to three passages, the cells were seeded in 6-well plates or on three-dimensional gelatin scaffolds and cultured in osteogenic medium. After 14 days in culture, the three-dimensional gelatin scaffolds were implanted subcutaneously in nude mice for 4 weeks. In 6-well plate culture, osteogenesis was assessed by alkaline phosphatase staining, Von Kossa staining, and reverse transcription-polymerase chain reaction （RT-PCR） analysis of the osteogenesis-specific genes type I collagen （COL I）, bone sialoprotein （BSP）, osteocalcin （OCN）, RUNX2, and osterix （OSX）. In three-dimensional gelatin scaffold culture, X-rays, hematoxylin/eosin staining, and immunohistochemical staining were used to examine bone formation. Results In vitro studies revealed that hDPSCs do possess osteogenic differentiation potential. In vivo studies revealed that hDPSCs seeded on gelatin scaffolds can form bone structures in heterotopic sites of nude mice. Conclusions These findings suggested that hDPSCs may be valuable as seed cells for bone tissue engineering. As a special stem cell source, hDPSCs may blaze a new path for bone tissue engineering.展开更多
基金supported by RC2DE020767 from the National Institute of Dental and Craniofacial Research (NIDCR), the National Institutes of Health (NIH)
文摘A tooth is a complex biological organ and consists of multiple tissues including the enamel, dentin, cementum and pulp. Tooth loss is the most common organ failure. Can a tooth be regenerated？ Can adult stem cells be orchestrated to regenerate tooth structures such as the enamel, dentin, cementum and dental pulp, or even an entire tooth？ If not, what are the therapeutically viable sources of stem cells for tooth regeneration？ Do stem cells necessarily need to be taken out of the body, and manipulated ex vivo before they are transplanted for tooth regeneration？ How can regenerated teeth be economically competitive with dental implants？ Would it be possible to make regenerated teeth affordable by a large segment of the population worldwide？ This review article explores existing and visionary approaches that address some of the above-mentioned questions. Tooth regeneration represents a revolution in stomatology as a shift in the paradigm from repair to regeneration： repair is by metal or artificial materials whereas regeneration is by biological restoration. Tooth regeneration is an extension of the concepts in the broad field of regenerative medicine to restore a tissue defect to its original form and function by biological substitutes.
文摘Background The seed cell is a core problem in bone tissue engineering research. Recent research indicates that human dental pulp stem cells （hDPSCs） can differentiate into osteoblasts in vitro, which suggests that they may become a new kind of seed cells for bone tissue engineering. The aim of this study was to evaluate the osteogenic differentiation of hDPSCs in vitro and bone-like tissue formation when transplanted with three-dimensional gelatin scaffolds in vivo, and hDPSCs may become appropriate seed cells for bone tissue engineering. Methods We have utilized enzymatic digestion to obtain hDPSCs from dental pulp tissue extracted during orthodontic treatment. After culturing and expansion to three passages, the cells were seeded in 6-well plates or on three-dimensional gelatin scaffolds and cultured in osteogenic medium. After 14 days in culture, the three-dimensional gelatin scaffolds were implanted subcutaneously in nude mice for 4 weeks. In 6-well plate culture, osteogenesis was assessed by alkaline phosphatase staining, Von Kossa staining, and reverse transcription-polymerase chain reaction （RT-PCR） analysis of the osteogenesis-specific genes type I collagen （COL I）, bone sialoprotein （BSP）, osteocalcin （OCN）, RUNX2, and osterix （OSX）. In three-dimensional gelatin scaffold culture, X-rays, hematoxylin/eosin staining, and immunohistochemical staining were used to examine bone formation. Results In vitro studies revealed that hDPSCs do possess osteogenic differentiation potential. In vivo studies revealed that hDPSCs seeded on gelatin scaffolds can form bone structures in heterotopic sites of nude mice. Conclusions These findings suggested that hDPSCs may be valuable as seed cells for bone tissue engineering. As a special stem cell source, hDPSCs may blaze a new path for bone tissue engineering.
