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 following new concept: healthy oral fu- tion is maintained by biological and biomechanical harmony among three s- tems: (1) oral tissues (host); (2) parasitic microorganisms of the oral cavity (parasites); and (3) biomaterials. The concept implies that oral diseases such as dental caries, periodontal disease, and temporomandibular disorders should be interpreted as "interface disorders" that result from...