Metal free restorations

There exists today a wide selection of different ceramic systems. An understanding of the basic structure of these various dental ceramics is important because their physical properties are a result of their underlying composition and this, accordingly, dictates the most appropriate choice for any given clinical situation.

In order to make a rational decision as to which material to use in which clinical situation, one needs to ask the following types of question:

• Does the restoration need to mask tooth discolouration? If so, how severe is this discolouration?
• Will retention of the restoration rely solely on resin-bonding (e.g. veneers) or will conventional retention form be available?
• What is the functional loading on the new restoration? For example, is the restoration a single-unit or a multi-unit bridge?
• Does the patient exhibit signs of tooth wear or parafunctional habits?

Please refer to our guide below.

A Guide to Ceramic Selection

CERAMIC SYSTEM	RESTORATION TYPES	INDICATIONS	CONTRAINDICATIONS	SUGGESTED USE
Zirconia based crowns CALYPSO CERCON PROCERA Zirconia	CROWNS and BRIDGES (up to 4 units)	PREMOLARS AND MOLARS Where metal free restoration is preferred	INLAYS, ONLAYS, ANTERIORS and VENEERS	Great strength for posteriors but aesthetics not as good as e.max or Procera Alumina. Can be cemented without risks of bonding procedure.
CERCON AESTHETIC (Porcelain buccal margin and Dentaurum Triceram veneering ceramic)	As above	Anteriors, premolars and molars	As above	Much improved aesthetics on Cercon, especially if axial wall reduction is adequate
PROCERA ALUMINA (Aluminium Oxide coping)	CROWNS, SIMPLE ANTERIOR BRIDGES, INLAYS, ONLAYS and VENEERS	All restorations, where more strength than e.max (Empress II) is required and underlying abutment colour may be a problem	Sharp line angles and uneven thickness of ceramic can cause fracturing	Stronger than e.max (Empress II) and more aesthetic than Calypso. Excellent for masking non-vital teeth. Models need to be scanned so undercuts present a problem if present in preparations.
The translucency of all-ceramic materials vary significantly and affect the final aesthetic outcome.
e.max Press  (Lithium Disilicate base) e.max ZirPress	CROWNS, SIMPLE ANTERIOR BRIDGES, INLAYS, ONLAYS, and VENEERS	All Restorations including ANTERIOR CROWNS and VENEERS	POSTERIOR CROWNS – Insufficient occlusal clearance, short clinical crowns or parafunction ANTERIOR CROWNS – Underlying abutment colour is dark, root filled or metallic post and core INLAYS and ONLAYS – Uneven thickness of ceramic, subgingival margins, parafunctions	Magnificent life-like aesthetics. Strength directly proportional to width of ceramic. Translucency can cause problems if abutment is dark but can be overcome in some situations by using opaque ingots and opaquers to mask colour.
CERAMAGE  (Composite with Zirconia filler)	ALL CROWNS, Small span Anterior and Posterior BRIDGES, INLAYS and ONLAYS Ideal for Implant retained Crowns to minimize load to fixture	Ideal for inlays and onlays in all posteriors Can be used for full crowns Significantly lower fracture rates and less technique sensitive so can be very successful replacing old amalgams where margins are undulating and restoration is of uneven thickness Less wear on opposing tooth structure Better marginal adaptation Easier to polish if adjusted	Unsuitable for veneers or long span bridges and difficult to bond perfectly if margins are subgingival	Qualities such as shade stability, fluorescence and life-like opalescence provide the completed restoration with an impressive aesthetic appearance. Wear properties similar to amalgam gives excellent life span to restoration. Fibre reinforced layer gives flexibility and strength when required.