TOKYO, Japan: It is likely the best-known component of any dental product developed by Kuraray Noritake Dental: 10-methacryloyloxydecyl dihydrogen phosphate, or MDP monomer for short. Developed more than 40 years ago and first used in a product in 1983, MDP is still the leading functional monomer used to establish a long-term, durable and stable bond to hydroxyapatite in tooth structure and to metal oxides in restorative materials, including oxide ceramics and metal alloys.