Navigating bonding decisions for glass ceramics and lithium disilicate

Science & TechLee Ann Brady, DMD

Like so many things in dentistry today, seating a restoration has become more complex. On one hand, the complexity means we have a broader range of material and technique choices to provide care for our patients. On the other hand, the complexity means there is more opportunity for error due to technique sensitivity. There is also the anxiety of trying to figure out which technique and material will give us the best clinical outcome.

For example, this applies to resin-based materials and techniques. Materials now allow for enhanced bond strengths, which can be achieved by preparing and conditioning the intaglio of the restorative material. As a result, the line between bonding and cementation has been blurred. We see terms such as “adhesively assisted cementation” and “mechanically assisted adhesion” that are used to describe a variety of hybrid techniques that exist somewhere between cementation and bonding.

The first step to making good material and technique decisions is to conceptualize things as a decision tree. By doing this, we can become comfortable with the different choices available. The variables include:

• preparation design;
• 
  
  
• the type of restoration;
• 
  
  
• partial coverage or full coverage;
• 
  
  
• the restorative material;
• 
  
  
• the amount of mechanical retention from the tooth preparation; and
• 
  
  
• the esthetic property of the cement desired.
• 
  
  

Different manufacturers offer different material choices, which can be thought of as families of products. For this article, I will use examples from the Ivoclar Vivadent family of products.