Zirconia has emerged as a prominent material for indirect dental restorations, necessitating a comprehensive understanding of its clinical handling, including cleaning, cementing, adhesion, and the use of zirconia primers.
Cementation Options
Clinicians have various options for cementing zirconia restorations, including modern bioactive cements, dual-cureresin-based systems, and self-etching dual-barrel resin cements. Additionally,certain types of zirconia allow for light curing of resin, expanding the range of adhesive techniques available.
Adhesion versus Cohesion
A critical distinction in restorative dentistry is between adhesion and cohesion. Adhesion refers to a full adhesive protocol, while cohesion involves using cement as a looting agent, relyingprimarily on the preparation for retention. This distinction influences thechoice of materials and techniques for cementation.
Preparation and Cementation Techniques
Proper preparation design is pivotal for successful zirconia restorations. A well-designed preparation with adequat eaxial wall height and taper can ensure crown retention even with traditional cements. In cases where ideal preparation is not feasible, adhesive techniques become essential. Traditional cements, such as glass ionomer and newer bioactive cements like can be effective with good preparation.
Common Challenges
A prevalent issue among clinicians is the debonding of zirconia crowns. This problem often stems from technique errors during preparation and cementation. Many dentists mistakenly believe that new materials guarantee strong adhesion without meticulous technique. Effective zirconia cementation requires careful handling to avoid contamination andensure proper adhesion.
Cleaning and Priming
Cleaning zirconia restorations before andafter try-in is crucial. Methods include sandblasting and using specific zirconia primers and cleaners. Each product has unique chemical properties that influence their effectiveness.
Priming and Adhesion
Achieving strong adhesion to zirconia necessitates using a zirconia-specific primer. Traditional silanes used for ceramic restorations are ineffective with zirconia. A zirconia primer, such as Silmet’s ProLink Cem Primer, contains MDP-based chemistry that ensures proper chemical bonding to zirconia. This primer must be applied as the initial layer, followed by the resin looting agent.
Clinical Protocol for Zirconia Crowns
Longevity and Future Considerations
Properly adhered zirconia crowns have thepotential to last 20-30 years. This durability underscores the importance of precise technique, as future removal of these restorations may be challenging. Adhering to the correct protocols ensures long-lasting outcomes and patient satisfaction.
In summary, successful zirconia restorations depend on understanding and implementing proper cleaning,cementing, adhesion, and priming techniques. As materials and methods continue to evolve, staying informed and adapting to best practices is essential for clinical success.
