Porcelain crowns or caps are used to cover weakened teeth, providing the beauty of porcelain and the strength of metal. In order to fit them correctly, it is necessary to reduce the tooth by only 1.2 mm in all its dimension, which will create the necessary space for the components of the caps.
Today, all-ceramic crowns are increasingly in demand due to the high aesthetic appeal they provide.
Zirconium is a highly biocompatible material with a high degree of hardness and is also white, making it a material with excellent functional and aesthetic properties for dentistry.
Today it is undoubtedly the material with which the best possible aesthetics can be achieved in dental reconstructions that in the past would have required less aesthetic metal components.
This is because zirconium has a bending strength of 900 mega-Pascals, a modulus of elasticity of 200 Giga-Pascals and a hardness of 1300 kg/mm2. These properties make it an excellent material to withstand chewing forces.
Porcelain inlays or onlays, on the other hand, are used in cases where it is necessary to replace a large part of the lost tooth structure due to erosion, caries or to reinforce endodontically decayed teeth.
This requires a 1.5 mm thickness of material in the chewing part of the tooth to restore function and aesthetics to the weakened tooth.
Ceramic onlays are the most conservative restorative treatment available today thanks to the development of new ceramics such as lithium disilicate, which has the property of adhering to the tooth. Thanks to this, together with the advance of new technologies, the manufacturing process of onlays has also evolved.
Ceramic onlays are made using the CAD-CAM process. Once the teeth have been prepared, they are scanned by means of a digital scanner in the mouth and the information is then sent by e-mail to the laboratory, which takes charge of the digital design and mills it using a computerised process based on aeronautical technology.
Lithium disilicate inlays require pre-treatment before they can bond to tooth structure, but once bonded they have the fracture resistance of natural enamel (400 Mpa).