The purpose of the present study is to examine the influence of melatonin on the structure, odontoblasts, and the periodicity of incremental lines of tooth dentin through the histological and analytics studies. These rats were divided into three groups: 1) a control group; 2) a low concentration group by melatonin medication; 3) a high concentration group by melatonin medication. On the melatonin treated group, the interval of the incremental lines was narrow. The new incremental line was confirmed in the incisor predentin and molar dentin of the melatonin treated groups. The expression of melatonin receptor was observed in odontoblasts of the control group. In the melatonin treated group, the expression of MTR2 was strongly observed. Ca and P content were increased in the melatonin treated group using SEM-EDS and EPMA analysis. It is considered that melatonin participates in the formation of incremental lines and the calcification mechanism of dentin.
The field of regenerative medicine has recently made marked advances in stem cell research. Adult stem cells, called somatic or tissue stem cells that can only be differentiated into limited cell types, have been generally used for regenerative medicine. However, with the development of iPS cells, tissues and cells of interest will be artificially generated and implanted into patients to repair sites of damage. In the present study, technical objectives for this purpose are summarized. Also, I described the special characteristics of regenerative medicine in the dental field, the idea to improve the Embryo Stem Cell Test (EST) of in vitro embryotoxicity test protocol using ES cells.
I suggest a unique new technology for QOL improvement of dental patient. This new pioneering technology must be innovative content. This time, some is not in the medical field, and then propose the following items with the aim of great development of the future of the dental office. 1) An automatic drug injection system that injects drugs into the body from a prosthesis in an emergency, 2) Intraoral treatment with phototoxicity-inducing substance, 3) Substitute for the eye using "Denture Camera", 4) Information system utilizing cavities in teeth and dentures.