Adhesively Luted Zirconia Restorations: Why and How? Masanao Inokoshia / Bart Van Meerbeekb Do
Why
Tribochemically silica sandblast/coat the zirconia surface at low pressure (1-2 bar) using silica-coated Al2O3 particles of up to 50 μm in size.
The zirconia surface needs not only be roughened, but also chemically activated to make zirconia more receptive for chemical interaction via zirconia primers applied in the next step.
Apply a combined 10-MDP/silane ceramic primer to the tribochemically silica sandblasted/coated zirconia.
10-MDP ionically bonds to zirconia; silane chemically interacts with the silica coated zirconia surface.
Lute the zirconia restoration using a composite cement.
To adhesively lute zirconia, composite cements are preferred over conventional cements (eg, glass-ionomer cements).
IAAD WORKING INSTRUCTIONS About a decade has passed since zirconia was introduced into dentistry. Although it is a relatively inert ceramic, dental zirconia can today no longer be considered “un-bondable” to tooth tissue. In the literature, different mechanical and chemical surface pretreatments have been recommended to improve the bonding effectiveness of composite cement to zirconia. Regarding mechanical pretreatment, tribochemical silica sandblasting/coating with silica-coated aluminium-oxide (Al2O3) particles, eg, using the CoJet (3M ESPE) or SilJet (Danville) systems, has been shown not only to roughen but also to chemically activate zirconia, thus making it more receptive for chemical bonding via silane (3-methacryloxypropyl-trimethoxysilane, 3-MPTS) coupling agents.1 Al2O3 (uncoated particles) sandblasting can be a second choice, but the resulting bond appeared less resistant to aging.4 To avoid the well-documented subsurface damage and zirconia-phase transformation induced by high pressure and large particle-size sandblasting, air abrasion should be applied at lower pressure (1 to 2 bar) using particles up to 50 μm in size.6,8 Regarding chemical pretreatment, silane, as within traditional ceramic primers, did not appear very effective on zirconia,2,3,7 while the functional monomer 10-MDP (10-methacryloyloxydecyl dihydrogen phosphate), widely known to durably bond to tooth tissue by ionic bond formation, has also been documented to chemically bond to zirconia, especially when applied on previously tribochemically silica sandblasted/coated zirconia.6,9-11
a
PhD Student, KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) and Dentistry, University Hospitals Leuven, Leuven, Belgium.
b
Professor, KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) and Dentistry, University Hospitals Leuven, Leuven, Belgium.
Correspondence: Professor Dr. Bart Van Meerbeek, KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) and Dentistry, University Hospitals Leuven, Kapucijnenvoer 7 blok a box 7001, 3000 Leuven, Belgium. Tel: +32-16-337587, Fax: +32-16-332752. e-mail: [email protected]
294
In particular, primers that contain both 10-MDP and silane – for instance, Clearfil Ceramic Primer (Kuraray Noritake) and Monobond Plus (Ivoclar Vivadent) – were shown to improve bonding to zirconia.5 Although application of a composite cement containing 10-MDP could further contribute to the bond strength to zirconia, the choice of cement appeared less decisive with regard to bond durability, at least as long as a composite cement was employed.4 Overall, the combination of mechanical and chemical zirconia-surface pretreatment was found to contribute to the durability of the bond of composite cements to zirconia ceramics. As a standard procedure, the application of tribochemical silica sandblasting/ coating followed by a combined 10-MDP/silane ceramic primer to zirconia can be clinically highly recommended. However, it remains to be determined whether the bond strength obtained will render macroretention of the tooth preparation unnecessary.
REFERENCES 1.
Chen L, Suh BI, Kim J, Tay FR. Evaluation of silica-coating techniques for zirconia bonding. Am J Dent 2011;24:79-84. 2. Derand T, Molin M, Kvam K. Bond strength of composite luting cement to zirconia ceramic surfaces. Dent Mater 2005;21:1158-1162. 3. Friederich R, Kern M. Resin bond strength to densely sintered alumina ceramic. Int J Prosthodont 2002;15:333-338. 4. Inokoshi M, De Munck J, Minakuchi S, Van Meerbeek B. Metaanalysis of Bonding Effectiveness to Zirconia Ceramics. J Dent Res 2014;93:329-334. 5. Inokoshi M, Poitevin A, De Munck J, Minakuchi S, Van Meerbeek B. Bonding effectiveness to different chemically pre-treated dental zirconia. Clin Oral Investig [Epub ahead of print]2013;doi:10.1007/s00784-0131152-7 6. Kern M, Barloi A, Yang B. Surface conditioning influences zirconia ceramic bonding. J Dent Res 2009;88:817-822. 7. Kern M, Wegner SM. Bonding to zirconia ceramic: adhesion methods and their durability. Dent Mater 1998;14:64-71. 8. Magne P, Paranhos MP, Burnett LH, Jr. New zirconia primer improves bond strength of resin-based cements. Dent Mater 2010;26:345-352. 9. Özcan M, Nijhuis H, Valandro LF. Effect of various surface conditioning methods on the adhesion of dual-cure resin cement with MDP functional monomer to zirconia after thermal aging. Dent Mater J 2008;27:99-104. 10. Yang B, Barloi A, Kern M. Influence of air-abrasion on zirconia ceramic bonding using an adhesive composite resin. Dent Mater 2010;26:44-50. 11. Yoshida K, Tsuo Y, Meng X, Atsuta M. Mechanical properties of dual-cured resin luting agents for ceramic restoration. J Prosthodont 2007;16:370-376.
The Journal of Adhesive Dentistry
Why
Tribochemically silica sandblast/coat the zirconia surface at low pressure (1-2 bar) using silica-coated Al2O3 particles of up to 50 μm in size.
The zirconia surface needs not only be roughened, but also chemically activated to make zirconia more receptive for chemical interaction via zirconia primers applied in the next step.
Apply a combined 10-MDP/silane ceramic primer to the tribochemically silica sandblasted/coated zirconia.
10-MDP ionically bonds to zirconia; silane chemically interacts with the silica coated zirconia surface.
Lute the zirconia restoration using a composite cement.
To adhesively lute zirconia, composite cements are preferred over conventional cements (eg, glass-ionomer cements).
IAAD WORKING INSTRUCTIONS About a decade has passed since zirconia was introduced into dentistry. Although it is a relatively inert ceramic, dental zirconia can today no longer be considered “un-bondable” to tooth tissue. In the literature, different mechanical and chemical surface pretreatments have been recommended to improve the bonding effectiveness of composite cement to zirconia. Regarding mechanical pretreatment, tribochemical silica sandblasting/coating with silica-coated aluminium-oxide (Al2O3) particles, eg, using the CoJet (3M ESPE) or SilJet (Danville) systems, has been shown not only to roughen but also to chemically activate zirconia, thus making it more receptive for chemical bonding via silane (3-methacryloxypropyl-trimethoxysilane, 3-MPTS) coupling agents.1 Al2O3 (uncoated particles) sandblasting can be a second choice, but the resulting bond appeared less resistant to aging.4 To avoid the well-documented subsurface damage and zirconia-phase transformation induced by high pressure and large particle-size sandblasting, air abrasion should be applied at lower pressure (1 to 2 bar) using particles up to 50 μm in size.6,8 Regarding chemical pretreatment, silane, as within traditional ceramic primers, did not appear very effective on zirconia,2,3,7 while the functional monomer 10-MDP (10-methacryloyloxydecyl dihydrogen phosphate), widely known to durably bond to tooth tissue by ionic bond formation, has also been documented to chemically bond to zirconia, especially when applied on previously tribochemically silica sandblasted/coated zirconia.6,9-11
a
PhD Student, KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) and Dentistry, University Hospitals Leuven, Leuven, Belgium.
b
Professor, KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) and Dentistry, University Hospitals Leuven, Leuven, Belgium.
Correspondence: Professor Dr. Bart Van Meerbeek, KU Leuven BIOMAT, Department of Oral Health Sciences, KU Leuven (University of Leuven) and Dentistry, University Hospitals Leuven, Kapucijnenvoer 7 blok a box 7001, 3000 Leuven, Belgium. Tel: +32-16-337587, Fax: +32-16-332752. e-mail: [email protected]
294
In particular, primers that contain both 10-MDP and silane – for instance, Clearfil Ceramic Primer (Kuraray Noritake) and Monobond Plus (Ivoclar Vivadent) – were shown to improve bonding to zirconia.5 Although application of a composite cement containing 10-MDP could further contribute to the bond strength to zirconia, the choice of cement appeared less decisive with regard to bond durability, at least as long as a composite cement was employed.4 Overall, the combination of mechanical and chemical zirconia-surface pretreatment was found to contribute to the durability of the bond of composite cements to zirconia ceramics. As a standard procedure, the application of tribochemical silica sandblasting/ coating followed by a combined 10-MDP/silane ceramic primer to zirconia can be clinically highly recommended. However, it remains to be determined whether the bond strength obtained will render macroretention of the tooth preparation unnecessary.
REFERENCES 1.
Chen L, Suh BI, Kim J, Tay FR. Evaluation of silica-coating techniques for zirconia bonding. Am J Dent 2011;24:79-84. 2. Derand T, Molin M, Kvam K. Bond strength of composite luting cement to zirconia ceramic surfaces. Dent Mater 2005;21:1158-1162. 3. Friederich R, Kern M. Resin bond strength to densely sintered alumina ceramic. Int J Prosthodont 2002;15:333-338. 4. Inokoshi M, De Munck J, Minakuchi S, Van Meerbeek B. Metaanalysis of Bonding Effectiveness to Zirconia Ceramics. J Dent Res 2014;93:329-334. 5. Inokoshi M, Poitevin A, De Munck J, Minakuchi S, Van Meerbeek B. Bonding effectiveness to different chemically pre-treated dental zirconia. Clin Oral Investig [Epub ahead of print]2013;doi:10.1007/s00784-0131152-7 6. Kern M, Barloi A, Yang B. Surface conditioning influences zirconia ceramic bonding. J Dent Res 2009;88:817-822. 7. Kern M, Wegner SM. Bonding to zirconia ceramic: adhesion methods and their durability. Dent Mater 1998;14:64-71. 8. Magne P, Paranhos MP, Burnett LH, Jr. New zirconia primer improves bond strength of resin-based cements. Dent Mater 2010;26:345-352. 9. Özcan M, Nijhuis H, Valandro LF. Effect of various surface conditioning methods on the adhesion of dual-cure resin cement with MDP functional monomer to zirconia after thermal aging. Dent Mater J 2008;27:99-104. 10. Yang B, Barloi A, Kern M. Influence of air-abrasion on zirconia ceramic bonding using an adhesive composite resin. Dent Mater 2010;26:44-50. 11. Yoshida K, Tsuo Y, Meng X, Atsuta M. Mechanical properties of dual-cured resin luting agents for ceramic restoration. J Prosthodont 2007;16:370-376.
The Journal of Adhesive Dentistry
