By: Lee Ann Brady, DMD
This topic originally appeared on Pankey.org. Dr. Brady granted permission for igniteDDS to share with our readers.
Zirconia restorations have become a go-to solution in modern dentistry due to their durability, aesthetics, and biocompatibility. However, adjusting zirconia requires a precise approach to maintain its integrity and prevent complications.
Whether youโre fine-tuning occlusion or refining contours, understanding the best techniques ensures long-lasting restorations and preserves opposing dentition.
Maintaining Aesthetic Integrity of Zirconia Restorations
Zirconia restorations are infused with color and then fired in a ceramic oven, but the color layer is relatively shallow. Over-adjusting can strip away this layer, revealing the base shade of the zirconia restorations and creating unwanted aesthetic discrepancies.
To maintain optimal aesthetics:
- Work closely with the dental lab to ensure precise occlusion and contacts, minimizing the need for extensive adjustments
- When adjustments are necessary, use fine diamonds or appropriate adjustment stones
- Always complete a rigorous polishing protocol to smooth and restore the surface
Why Zirconia Polishing Matters for More than Aesthetics
Zirconia is a highly durable material, but if improperly adjusted, it can become an abrasive surface that accelerates tooth wear on opposing dentition. A finely polished zirconia surface, on the other hand, minimizes this risk. Thatโs why a rigorous polishing protocol is essential after any adjustments.
Another key reason for cautious zirconia adjustments is the risk of crack propagation, particularly in 5Y zirconia. Like other ceramics, zirconia is susceptible to microscopic cracks if angular defects are introduced during adjustments. These defects can compromise long-term stability if not properly polished out.
The Zirconia Adjustment and Polishing Protocol
If zirconia restorations are adjusted with a medium or coarse grit instrument, the surface becomes rough, requiring significantly more effort to restore smoothness.
To streamline the process, zirconia adjustments should be made with a fine diamond and a high-speed handpiece, such as a red, white, or yellow stripe diamond. Alternatively, adjustment stones on a slow-speed straight shank handpiece can prevent excessive roughness.
Once zirconia adjustments are made, I perform a two-minute, two-step zirconia polishing protocol using diamond polishing paste.
Precision is Key
Zirconia restorations, when properly handled, offer exceptional longevity and beauty. By refining your adjustment technique, you help ensure these zirconia restorations function optimally for years to come.
While some level of adjustment is often unavoidable, the goal should always be minimization and methodical execution. Using the right instruments and following an intentional polishing sequence ensures better long-term performance, improved aesthetics, and reduced risk of opposing tooth wear.
For more in-depth exploration of fixed prosthodontic restorations, I invite you to enroll inย Mastering Advanced Prosthodontic Techniquesโa hands-on course focused on complex interdisciplinary planning and advanced restorative sequencing for fixed prosthodontic cases.
