CEREC ONE-VISIT CROWNS
We strive for the most accurate, conservative, and biocompatible dentistry possible. Traditionally, we think about inlays, onlays and crowns as distinct categories. In the traditional method, the tooth is prepped, rubber impressions are taken, and the patient leaves with a temporary crown. The patient returns approximately 3 weeks later for the final restoration. This is inconvenient and we are often forced to aggressively drill closer to the gumline for the sole purpose of obtaining mechanical retention to hold on a temporary crown. The Cerec technology we use in our practice eliminates the need for a temporary crown, multiple appointments, and those strict categories defining the type of restoration. We are able to prep teeth on a continuum of inlay to crown minimizing the amount of healthy tooth we need to remove. Our prosthesis are metal-free, biocompatible and bonded.
After assessing the tooth, we numb the area and prep the tooth, drilling as little as necessary. Rather than using an impression tray, which is uncomfortable and subject to minor distortion, we take pictures of the tooth using the Cerec camera. At this point, the patient gets an hour break, while we design the 3D tooth which is both anatomically correct, and fits the specific parameters of your mouth. Once the tooth is designed, the computer mills the crown from a ceramic block with exceptional accuracy. When complete, the final restoration is bonded to the tooth using a resin bonding agent designed to prevent leakage.
Types of crowns:
Porcelain fused to metal (PFM)
Many people comment that when they look in their mouth they see a dark line at the gumline that wasn’t originally there, or a distinctly opaque looking crown. They are surprised to the learn that the dark line is actually a metal alloy containing various metals such as: cobalt, nickel, tin, zinc, silver, or gold. For many people, these metals can cause direct irritation, which is often responsible for the gum moving away and that dark line appearing. Some people are also especially susceptible to the galvanic reaction that takes place when you have multiple metals in your mouth. For more information on the galvanic, battery reaction please see Dr. Koral’s illustration below.
Ceramic (non-metal crowns)
Ceramic crowns are a great alternative to the porcelain fused to metal crowns. The two main types of ceramic crowns used in our office are E-MAX and zirconium. Emax (lithium dicilicate) is one of the more recent advances in ceramic restorations, and is our material of choice for our single unit crowns and onlays. It has vastly superior durability, compatibility, and esthetics, when compared to older types of ceramics or PFM restorations. Since they are pure ceramic: they don’t pose a risk to patients with metal allergies, do not contribute to the “battery in your mouth,” and are very well tolerated by the bone and gums. In the past, if a tooth broke below the gumline, surgical procedures were needed to remove more bone before placing a PFM crown due to the metal’s lack of biocompatibility. With ceramic restorations we are able to bury the margins below the gumline without tissue irritation or the need for additional surgeries. Beyond the biocompatibity advantages, ceramic crowns are considered the most esthetic option since they are made from a translucent material that mimics the reflective nature of natural teeth. Zirconium and E-MAX crowns are also both lighter and thinner than traditional PFM crowns, which allows us to be more conservative.