Porcelain Crowns and Onlays

Porcelain Crowns and Onlays

The porcelain crown or veneer is a total tooth covering that simulates the entire external anatomy of the natural tooth. Its thickness ranges from 1-1.2 mm. They can be made only with porcelain, or with a core of another material to give it more consistency, such as metal or more recently lithium disilicate (EMAX) or zirconium.

The Onlay or porcelain inlay is a fragment of high resistance ceramic that adheres to the surface of the tooth when these have suffered a great loss of surface due to caries, erosion or to reinforce those teeth that have suffered an endodoncy. Onlays reconstruct teeth in a conservative way.

Step-by-step technique

The tooth must be reduced in all its contour between 1.0 and 1.2 mm with a conical shape of 6º, so that when placing the crown. The crown should slide along the walls of the tooth until it fits perfectly and totally airtight. Once the preparation is complete, a digital impression is taken and a temporary crown is placed. Once the adaptation tests have been carried out, it is cemented with a special adhesive or cement.

1.5 mm of material thickness is needed to be able to resist the masticatory forces on the surface of the occlusal tooth only. The rest of the tooth remains intact. Once the preparation is finished, a digital impression is taken and a provisional one is placed. Once the appropriate adjustments have been made, it is bonded with a special cement.


They are used when a large amount of tooth tissue has been lost, for example after a large cavity or trauma, as retention of a veneer or filling would be very difficult due to the large loss of tooth structure. They are also used in cases of endodontic teeth. To give consistency to the whole tooth and avoid possible fractures, as endodontic teeth are very weak after treatment.

Metal-free crowns and porcelain onlays

Porcelain crowns or veneers are used to cover weakened teeth by providing the beauty of porcelain and the strength of metal. It is necessary to reduce the tooth by only 1.2 mm in all its dimensions to create the necessary space for the components of the veneers.

Today, all-ceramic crowns are in increasing demand due to the high aesthetics they provide.
Zirconium is a highly biocompatible material with great 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 you obtain the best possible aesthetics in reconstructions that would have required less aesthetic metal components in the past.

Zirconium has a flexural 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 for supporting masticatory forces.
Porcelain inlays or onlays 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 endodontic teeth. It is necessary 1.5 mm of material thickness in the masticatory part of the tooth, to return the function and aesthetics to the weakened tooth.

Onlays are the most conservative restorative treatment we have today thanks to the development of new ceramics such as lithium disilicate which has the property of bonding/adhering to the tooth. The manufacturing process of onlays has evolved with new technologies. They are made by means of the CAD-CAM process. Once the teeth are prepared, they are scanned by a digital scanner in the mouth. The information is sent to the laboratory by e-mail, digitally designed and milled using a computerized process based on aeronautical technology.
Lithium disilicate inlays need to be pre-treated before they can bond to the tooth structure and once bonded they have the fracture resistance of natural enamel. 400 Mpa.

Crowns on implants

Dental implants are artificial titanium roots that arise to meet the aesthetic, masticatory and phonetic needs that are diminished after the loss of natural teeth.

In the absence of one or more teeth, patients request a treatment option that solves the aesthetic and functional problem in the most conservative way possible, that is, avoiding reducing the adjacent teeth for the preparation of a bridge. And this is only achieved by means of dental implants.
Although many materials have been developed over the course of history, the material used today is titanium.

Titanium is not only a material that is very biocompatible with the human organism, but it also has the ability to bond living bone intimately to its surface.
In this way, the bone accepts the titanium as if it were actually part of the body’s own structure, thus producing a biological weld.
Once the implants have healed, the prostheses (caps) are stabilised on them, which function exactly like natural teeth.
Dental implants will allow us to chew with total comfort, smile and speak with the same security as with our own teeth.

In some specific and favourable cases, the patient, after undergoing implant surgery, can have a provisional prosthesis inserted on the same day as the surgery. This type of treatment provides the highest level of comfort, rehabilitation and readaptation of the patient to daily life, but in order for it to be carried out, a series of indispensable characteristics must be met.