Ceramic Veneer Bridge

A bridge is a tooth-supported, fixed dental prosthesis. It consists of the bridge anchors on crowned abutment teeth and one or more pontics to replace missing teeth. If the esthetically important areas of the bridge construction are coated with tooth-colored ceramic, it is called a ceramic veneer bridge (synonyms: veneer ceramic bridge, metal ceramic bridge). A ceramic veneer bridge has a framework made of metal, most of which is coated with tooth-colored ceramic. The framework itself can be made of either a gold-bearing alloy or non-precious metal alloys (NEM). The ceramic can be matched to the natural tooth color as far as possible, so that the denture meets high esthetic requirements. Ceramic veneers have a number of advantages:

  • High biocompatibility – very well tolerated by the body.
  • High color stability – even with a retention time in the mouth for many years.
  • High abrasion resistance
  • High chemical resistance
  • Lower thermal conductivity than metal
  • Smooth surface – thus hardly any adhesion of biofilm (bacterial coating).

Indications (areas of application)

  • Gap closure
  • Preventing tooth migration – tipping into the gap, elongation (the outgrowth of a tooth from its bone compartment) of the antagonist (opposite tooth) into the gap.
  • Restoration of phonetics
  • Restoration of aesthetics
  • Restoration of the chewing function
  • Support zone preservation

Contraindications

  • Severely loosened abutment teeth
  • Bruxism (teeth grinding or clenching) – risk of chipping (the shearing off of parts of the ceramic veneer) due to the high forces during grinding
  • Large, arched spans – If, for example, all upper anterior teeth are missing and the course of the formerly tooth-bearing jawbone is too arched, fixed dentures cannot be planned for static reasons.

The procedure

I. Dentist

  • Preparation of abutment teeth to receive the bridge anchors – If necessary, carious tooth structure must be removed and the tooth must be provided with a build-up filling before preparation (grinding the teeth).
  • Preparation – The teeth are circularly ground and reduced in their occlusal height (height of the occlusal surfaces) to create space for the material thickness of the subsequent bridge anchors.
  • Impressions of both jaws
  • Bite taking
  • Jaw relation determination – If support zones (occlusion/interlock of upper with lower molars) are resolved, the distance between the upper and lower jaw bases must be defined.
  • Temporary restoration – fabrication of a simple plastic bridge to protect the prepared teeth and prevent tooth migration until the definitive (final) bridge is placed.
  • Selection of the tooth color

II. dental laboratory

  • Production of plaster models based on the jaw impressions.
  • Articulating – transferring the models into the so-called articulator (device for imitating the jaw joint movements) on the basis of the bite impression and jaw relation determination.
  • Wax modeling – On the abutment teeth converted into plaster, the dental technician first models crowns made of wax, which are connected by the subsequent pontic made of wax.
  • Metal casting – Casting channels made of wax are attached to this wax modeling. Then the modeling is embedded in a casting muffle. In a furnace, the wax is burned out without residue. This creates cavities, which are filled with molten metal via the casting channels in a vacuum centrifugal process.
  • Elaboration – The metal framework cast in this way is de-bedded after cooling, separated from the casting channels and elaborated.

III Dentist

Before making the ceramic veneer is a so-called framework trial at the dentist. Here, the bridge is checked for its insertion direction (problem-free placement on the abutment teeth) and its marginal fit (transition of the crown to the natural tooth). Corrections to the height of the framework, which must still leave sufficient space for the veneer, can still be made at this stage. IV. Dental laboratory

  • Veneering – Ceramic materials of a porridge-like consistency are applied layer by layer to the metal framework using the finest brush technique.Here, the dental technician must take into account the volume shrinkage due to the subsequent sintering firing.
  • Raw firing – The first firing gives the ceramic its hardness and abrasion resistance, but still has a rough surface.

V. Dentist

Raw firing try-in – In the dental practice, this can still be corrections, for example, to the shape of the veneer or occlusion (chewing closure and chewing movements) and color corrections are forwarded to the laboratory. VI. dental laboratory

  • Glaze firing – The final glaze firing gives the ceramic veneer its surface finish, making it highly lustrous and providing little opportunity for biofilm (bacterial plaque) to adhere.

VII Dentist

  • Cleaning the prepared teeth
  • Placement – The finished bridge is conventionally (with conventional cements, e.g. zinc phosphate or glass ionomer cement) permanently attached to the abutment teeth.
  • Removal of excess cement after its setting phase.
  • Checking the occlusion (the chewing closure and chewing movements).

After the procedure

  • Timely control date
  • Regular recalls and optimization of oral hygiene techniques at home to allow for a long retention of the dentures