Since 2002, the Tohoku University Graduate School of Dentistry has proposed Interface Oral Health Science as a major theme for next-generation dental research. That theme is based on the innovative concept that healthy oral function is provided by biological and biomechanical harmony among three systems: (1) oral tissues including the teeth, mucosa, bones, and muscles (host); (2) parasitic microorganisms of the oral cavity (parasites); and (3) biomaterials. The concept posits that oral diseases such as dental caries, periodontal disease, and tempo- mandibular disorders should be interpreted...