In the present study, we investigated the desorption behaviors of fibronectin (Fn) adsorbed on titanium (Ti) surface by surfactant treatment using 27MHz QCM method. Au was used as a comparison with Ti. The adsorbed amounts of Fn to Au and Ti were almost the same, but the desorbed amounts of Fn from Au were significantly higher than those from Ti. Greater desorption of rate of Fn from Au was recognized compared to that from Ti. No significant difference in Kobs during 5 min for the adsorption process existed between Au and Ti, but Au showed significantly larger Kobs for desorption process than Ti. It means the desorption rate of adsorbed Fn to Au was more rapid to Ti. It was revealed that the desorption of Fn adsorbed on Ti was less likely than that of Fn adsorbed on Au, and that adsorption on Ti was stable. This may be one of the factors for getting better osteointegration of Ti.

In vitro studies using cultured cells in dental biomaterial research have predominantly been conducted under near-neutral culture conditions, while investigations under acidic or alkaline conditions have been limited. To date, few studies have addressed the fundamental question of how fluctuations in extracellular pH affect cell viability as basic in vitro data. In the present study, we examined changes in cell viability in response to zinc oxide under acidic and alkaline extracellular pH conditions using the MTT assay.

The effect of zinc oxide concentrations on cell viability was smoller under alkaline conditions than under acidic conditions, when compared with the control. Under alkaline conditions, cell viability increased and the IC50 value was higher than in the control. Future research to investigate not only zinc oxide, but also other metal ions and inorganic or organic materials is needed. These studies may provide fundamental data on dental biomaterials in the biological environment and potentially serve as important sources of information in the field of regenerative medicine.

The teeth and oral cavity have been repaired and functionally augmented by prosthetic materials since ancient times in the field of dentistry. This is explained by the fact that artificial materials have been specifically developed in dentistry, and such materials have played more important roles in dentistry than in other medical fields. Currently, a major revolution is taking place in dental molding technology. Digitalization has led to the use of lost-wax casting techniques and the decline of precious metals such as gold alloys and gold-silver-palladium alloys.Furthermore, implants, cosmetic dentistry and computer-assisted orthodontics are rapidly developing. These new technologies also involve regenerative and tissue engineering techniques. The development and application of dental technology over the next half century may be completely different from that of the past half century. Dental professionals need to become familiar with these new techniques. I believe that the time will come when dental clinics will no longer be able to operate simply by improving old techniques. This time, I have summarized important information about research in the field of regeneration in dentistry.