Five Common Mistakes When Working with Zirconia and How to Avoid Them

Working with zirconia is a popular choice for many dental professionals due to its strength, durability, and aesthetic appeal. However, there are several mistakes that can negatively affect the results of zirconia restorations. One of the most common errors is not choosing the right type of zirconia for the specific restoration. Monolayer and Multilayer zirconia offer varying strengths and translucency levels, and selecting the wrong one can lead to a restoration that is either too weak or does not look natural. It's essential to understand the different properties of the materials before making a choice. For posterior restorations, Monolayer zirconia, which is known for its strength, may be the best option. For anterior restorations where aesthetics are important, Multilayer zirconia is ideal, as it combines translucency with strength.

Another mistake is improper milling techniques. Milling zirconia requires precision, and using incorrect settings or equipment can result in inaccurate restorations or poor fit. If the zirconia is milled too quickly or with excessive heat, it may become brittle and prone to fracture. To avoid this, always ensure that the milling machine settings align with the manufacturer’s recommendations. This includes adjusting speed, temperature, and cooling to match the specific type of zirconia being used. Regular maintenance of your equipment is also crucial to ensure that the milling process goes smoothly and results in precise restorations.

Failing to fully sinter the zirconia is another common mistake. If zirconia is not properly sintered, it will remain soft and can break or deform more easily. This is especially true for pre-sintered zirconia, which requires a second sintering process after milling. To avoid this, it’s important to follow the recommended sintering cycle, ensuring that the zirconia reaches the correct temperature and duration for full hardness and strength. Check the sintering parameters carefully to guarantee that the material is fully cured before use.

After milling, many dental professionals overlook the need for proper post-milling adjustments. Failing to carefully adjust the restoration can lead to issues such as poor occlusion, discomfort, or failure of the restoration. It’s essential to take the time to make sure that the restoration fits well, especially in areas that require fine-tuning. Adjusting occlusion and contact points properly can ensure that the restoration functions well and does not cause issues for the patient. It’s best to use appropriate tools such as diamond burs to make any necessary adjustments, ensuring that the surface remains intact without compromising the fit.

Lastly, improper cementation can result in long-term issues. Using the wrong type of cement or applying it incorrectly can lead to bonding failure, sensitivity, or the early loss of the restoration. To avoid this, it’s crucial to use the correct resin cement specifically designed for zirconia restorations. Proper cleaning of the internal surface of the zirconia restoration is also essential before cementing, as contaminants can interfere with the bonding process. Additionally, always follow the manufacturer’s instructions for curing times and application procedures to ensure a strong bond.

By understanding these common mistakes and taking proactive steps to avoid them, dental professionals can achieve better outcomes when working with zirconia. Selecting the correct type of zirconia, using the right milling settings, fully sintering the material, making necessary adjustments, and ensuring proper cementation are all essential steps to ensure that zirconia restorations are both durable and aesthetically pleasing.