Japan is one of the most advanced countries in the field of regenerative medical research. However, in clinical dentistry, "regenerative medicine" is much less known than operative dentistry and prosthetic treatments. Despite the rapid development of regenerative medicine, enactment of relevant laws, and their interests in practicing regenerative medicine, dentists remain hesitant to provide regenerative therapies to patients. After graduating from a dental school, and working at several dental clinics for eight years, I continued my studies by pursuing a doctoral degree at my alma mater. My graduate studies provided me an opportunity to pursue my strong interest in medical research, and I became particularly committed to the study of stem cells, and I obtained a PhD in developmental and regenerative medicine. Currently, in addition to being engaged in stem cell research at the university, I teach developmental biology and regenerative medicine and other related clinical dentistry topics to undergraduate and graduate students. To increase familiarity with regenerative medicine in dentistry, I am seeking to overcome the disadvantages of regenerative medicine in dentistry. In this paper, I introduce three approaches for overcoming the disadvantages of regenerative medicine in dentistry. I have developed these approaches as a result of my involvement in this field from various perspectives as a dentist. Finally, I propose further possibilities for dental treatment.

The aim of this study was to evaluate by fine line reproducibility test the reproducibility of fine details in a combined impression with new injection-type alginate impression material compared with that of agar impression. The dental cast was made with the impression, and the surface roughness of the cast was measured. The results suggest that, while hard plaster ( α -gypsum) must be used in case the combined impression was taken with agar and alginate, dental super hard stone (modified α-gypsum) can be used in case the combined impression was taken with new injection alginate and alginate, allowing more accurate models to be made.

The aim of the present study was to examine the reactions in the interface between tissues and pure titanium. The adsorption behaviors of the extracellular matrix proteins HFG and HFN on titanium and gold were compared. The amount of adsorbed proteins on the metallic surfaces was measured after adsorption and desorption tests, using atomic force microscopy. The conformation changes of the proteins adsorbed were examined with a Fourier transform infrared spectrophotometer. The results showed that the adsorption of the two proteins were greater on the titanium plates than on the gold plates. It is reasonable to assume that proteins adsorb to surfaces through several steps, and that both HFG and HFN attach mainly to gold by physical adsorption, but to titanium by chemical adsorption. Furthermore, the conformation changes for both test proteins were greater on the titanium plates than on the gold plates. The initial adsorption of extracellular matrix proteins to metal is an important factor in determining the biocompatibility of a dental material in the oral cavity. This testing method might be effective when developing new active dental implants.

Wolffʼs law indicated that bone tissues are influenced by mechanical force and adapt bone structure to mechanical usage. According to this law, it is assumed the dental implant body could influence bone metabolism and induce deformation of shape of the jawbone during long term period, because the dental implant bodies locate in the bone matrix and directly connect with mineralized bone tissue. The aim of this study is to ascertain whether dental implant treatments influence deformation of shape of the jawbone or not. For this purpose, we used plaster models belong to 4 patients whose multiple dental implants have been passed at least more than ten years and compared the precise 3D positions of the dental implant bodies in past (old) and present (new) plaster models of the same patient by using the laser 3D measurement technique. The results of the study demonstrate that the multiple dental implants caused deformation of shape of the jawbone for long term period of the dental implant occlusion, and suggest that the phenomenon should be considered carefully on occlusal management of dental implants.

A 71-year-old female patient presented with the right articular process dysplasia. She had not received any dental treatment for more than 20 years. A full denture in the upper jaw and a partial denture in the lower jaw were used to restore function. The lack of articular process meant that there was no guide by the temporomandibular joint, so it was very difficult to take a bite registration. The gothic arch tracing method was chosen as the registration technique, and the tracing device was set up so that there would be as little change as possible, since changes in the vertical dimension easily cause errors. The drawing was asymmetrical and always deviated to the right. Due to the difficulty of the case, the gothic arch tracing was obtained not only for the examination but also for the remounting adjustment, and the final denture was made in the same way. Good results were obtained after 6 months of final denture placement.