After Kuraray introduced the first adhesive monomer in dental history by inventing the phosphate monomer Phenyl-P in 1976, its molecular structure was improved in 1983 by creating a molecule with greater adhesive capability to the tooth structure and an affinity for metal. The result of this development work was the MDP monomer (10-Methacryloyloxydecyl dihydrogen phosphate), which convinced users by its special monomer structure. MDP provides CHEMICAL ADHESION & not mechanical or micro-mechanical bonding. This phosphate monomer was extremely effective for enamel, dentine and on metal alloys. Consequently, PANAVIA, including the MDP monomer, was introduced as a high-performance adhesive resin cement for the cementation to tooth structure and to metals. The impressive success of PANAVIA encouraged Kuraray to integrate the MDP monomer into other bonding systems as well as to obtain a high degree of adhesion to tooth substrate from the formation of a chemical bonding. MDP is now present in Clearfil SE Bond, S3 Bond, Protect Bond, Teethmate, Alloy Primer, Ceramic Primer, Porcelain Repair System.

MDPB monomer – Antibacterial Monomer
Antibacterial effects of the MDPB monomer

The primer of CLEARFIL PROTECT BOND has antibacterial effects against bacteria by direct contact thanks to the integrated functional MDPB monomer. As is the case with so many modern developments, the question, “How can that work?” can be answered relatively easily: the pyridinium group as a component of the MDPB monomer (12-Methacryloyloxydodecyl pyridinium bromide) is positively charged. The cell structures of bacteria are generally negatively charged, which is why they are automatically attracted by the positively charged contact points of the MDPB monomer. They then loose their electrical balance, destroying the cell membrane of the bacteria. The bacteria are killed by this process, which is also known as bacteriolysis.

Long term Protection – no secondary caries

Immediately after the polymerization of the composite (such as CLEARFIL AP-X), CLEARFIL PROTECT BOND has already achieved an optimal sealing at the margin thanks to its high degree of initial adhesion.

Moreover, it remains possible that long-term protection has been provided in the form of the MDPB monomer. It is expected that the product prevents the absorption of bacteria by a change in the surface structure, contributing in the long run to protection from secondary caries. The bonding layer releases small quantities of fluoride to strengthen the neighboring tooth hard structure. A special copolymer aids in preventing shrinkage of the bonding layer and the consequent negative effects on the bond strength.