cosmetic dentistry_ beauty & science International

16 I I industry report _ CLEARFIL SE BOND _SinceDrRaphaelBowen developed the Bis-GMA oligomer in the early 1960s and Dr Michael Buonocore introduced the phospho- ric-acid etching technique for enamel cavity walls, fol- lowed by the development of dentine bonding, aes- thetic adhesive resin com- positerestorations—inareas suchastheocclusalsurfaces of posterior teeth—were widely performed in Japan beforeanyothercountryintheworld.Theseaesthetic adhesive restorations have contributed greatly to the improvement of the oral health of the Japanese population. About 30 years ago, Kuraray developed CLEARFIL BOND, which was the first generation of a clinically successful resin bonding containing phenyl-P mono- mer as an adhesion-promoting monomer. Thereafter, light-cure technology was introduced to resin bond- ing, leading to the development of the light-cured resinbondingagentCLEARFILPHOTOBOND.Asanext step, Kuraray began developing an easier-to-use and more biocompatible resin bonding agent, resulting in the introduction of the world’s first self-etching resinbondingagent—CLEARFILLINERBOND2—which doesnotrequirewaterrinsingafterpriming.Thistype of resin bonding is known as two-step simplified bondingintheUS. BasedonCLEARFILLINERBOND2,Kurarayfurther improved and simplified the system. The result was CLEARFIL SE BOND, which consists of a one-bottle primerandone-bottlebond.WithCLEARFILSEBOND, a truly two-step, self-etching primer resin bonding systemwaslaunched,thatcreatesstrongadhesionto bothenamelanddentine. _Composition of CLEARFIL SE BOND TheCLEARFILSEBONDkitconsistsofasingleliquid primer, a single liquid bonding agent and accessories. The primer has a self-etching effect, and comprises HEMA (2-hydroxyethyl methacrylate), hydrophilic dimethacrylate,MDP(10-methacryloyloxydecyldihy- drogen phosphate, adhesion-promoting monomer), N,N-diethanol-p-toluidine, D,L-camphor-quinone, and water. The bonding agent comprises silanated colloidal silica, bisphenol A diglycidyl-methacrylate, HEMA, hydrophobic dimethacrylate, MDP, N,N-di- ethanol-p-toluidineandD,L-camphor-quinone. OnesignificantfeatureofCLEARFILSEBONDisthat itsavestime,sinceitisnotnecessarytorinsetheprimer with water or to evaporate the solvent with light air- flow. As soon as the cavity surface has been treated with the primer, MDP is able to penetrate the cavity wall, self-etching mineral components of the tooth tissue and dissolving the smear layer created on the cavity walls during tissue reduction in 20 seconds. The subsequently applied bonding agent is able to strengthen the adhesion between the tooth tissue cosmeticdentistry 3_2011 Basic technical properties of CLEARFILSE BOND Authors_Dr Toshimoto Yamada & Dr Junpei Sugizaki, Japan Fig. 3_FE-SEM (argon ion beam etched surface; x 10,000) of the resin–enamel interface. The upper half is the set bonding layer and the lower half is the enamel layer. The superficial enamel was finely and densely etched. Polymerizable group Hydrophobic group Hydrophobic group Forming the chemical bond with calcium and hydroxylapatie Fig. 2 Fig. 3 Fig. 1