Effects of in Vitro Angiogenesis by Nano or Submicron Diamond Particles

24 Introduction Diamond dental points are widely used for cutting and grinding in the oral cavity at dental clinic. The diamond particles used for the bars have an average diameter of about 22nm-880μ m, and are fixed to a stainless steel shaft without gaps using nickel coating [1-3]. Diamond particles detached during cutting and grinding in the mouth are aspirated using a vacuum device. However, some particles may remain in the mouth. In addition, diamond particles stirred up into the air during cutting and grinding may enter the respiratory tract through the pharynx and nasal cavity of a patient or dentist. Diamond particles have been considered to be non-biological problems because they are made of carbon. However, diamond particles, which seem to pose no problem regarding their components, are a concern in terms of biological safety when they enter the human body in the form of nano or submicron particles [4-9]. In the present study, we investigated the effects of nano or submicron diamond particles on cell proliferation and in vitro angiogenesis to examine their biological safety.