The purpose of this study was to assess the quantitative three-dimensional (3-D) effects of orthognathic surgery on skeletal and pharyngeal airway morphology.The patients were 22 Japanese females w...

The fields of regenerative medicine and stem cell-based tissue engineering hold great potential for treating a wide range of tissue and organ defects. Stem cells are ideal candidates for regenerative medicine because they are undifferentiated cells with the capacity for self-renewal, rapid proliferation, multilineage differentiation, and expression of pluripotency-associated genes. Human dental pulp stem cells (DPSCs) consist of various cell types (including stem cells) and possess multilineage differentiation potential. Owing to their easy isolation and rapid proliferation, DPSCs and their derivatives are considered promising candidates for repairing injured tissues. Recent advances in gene engineering have enabled cells to express specific genes of interest, leading to the secretion of medically important proteins or the alteration of cell behavior. For example, transient expression of Yamanaka’s factors in DPSCs can induce transdifferentiation into induced pluripotent stem cells (iPSCs). These gene-engineered cells represent valuable candidates for regenerative medicine, including stem cell therapies and tissue engineering. However, challenges remain in their development and application, particularly regarding safety, efficacy, and scalability. This review summarizes current knowledge on gene-engineered DPSCs and their derivatives and explores possible clinical applications, with a special focus on oral regeneration.

Background: Dental pulp (DP) is a connective tissue composed of various cell types, including fibroblasts, neurons, adipocytes, endothelial cells, and odontoblasts. It contains a rich supply of pluripotent stem cells, making it an important resource for cell-based regenerative medicine. However, current stem cell collection methods rely heavily on the enzymatic digestion of dissected DP tissue to isolate and propagate primary cells, which often results in low recovery rates and reduced cell survival, particularly from deciduous teeth. Methods: We developed a novel and efficient method to obtain a sufficient number of cells through a one-step cultivation process of isolated DP. After the brief digestion of DP with proteolytic enzymes, it was scratched onto a culture dish and cultured in a suitable medium. By day 2, the cells began to spread radially from DP, and by day 10, they reached a semi-confluent state. Cells harvested through trypsinization consistently yielded over 1 million cells, and after re-cultivation, the cells could be propagated for more than ten passages. Results: The proliferative and differentiation capacities of the cells after the 10th passage were comparable to those from the first passage. The cells expressed alkaline phosphatase as an undifferentiation marker. Similarly, they also maintained the constitutive expression of stem cell-specific markers and differentiation-related markers, even after the 10th passage. Conclusions: This method, termed “scratch-based isolation of primary cells from human dental pulps (SCIP)”, enables the efficient isolation of a large number of DP cells with minimal equipment and operator variability, while preserving cell integrity. Its simplicity, high success rate, and adaptability for patients with genetic diseases make it a valuable tool for regenerative medicine research and clinical applications.