Turner & Goldrich offers crown and bridge restorations in both traditional metal based construction techniques and a range of all ceramic options that will meet all our clients’ requirements. With Cad Cam being the future of dentistry it has become a large part of our laboratory. We offer solutions to use both traditional and digital techniques, with guidelines shown below to indicate where these materials can be ideally used.

For our aesthetically challenging cases, we encourage patients to attend the lab for a personal consultation by one of our highly skilled technicians to ascertain the exact shade (colour) required for the restoration. Other aspects that form part of this appointment would be to establish patient preferences, smile-line assessment, facial measurements and a photographic record. The patient may need to return to the lab after the dentist does the try-in of the crown or bridge, if necessary, for a final colourisation.

PFM - Porcelain Bonded to Metal;

Porcelain bonded to metal has been the main-stay of dental technology and the first choice of dentistry as a treatment option for the past forty years. It has longevity, is stable and requires little to basic equipment to produce. In comparison PFM today cannot match all porcelain alternatives in most indications. They are growing in popularity providing, far superior aesthetic results. In many cases PFM will remain a reasonable option for some time to come.

Indications;

* All restorative procedures.
* A material offering lower cost.
* Excellent where devitalized teeth are present.
* Where partial dentures need to be retained, PFM is often a preferred choice.
* Where precision attachments are required it is still the first choice.
* Very suited where paranormal function exists.
* Excellent solution where there is excessive heavy bite history or TMJ joint issues.
* Can be compromised aesthetically owing to the metal base.
* May lack vitality when there is lack of room.

Guidelines for crowns and bridges;

* Almost all restorative procedures including implants can be constructed using IPS e.max porcelain on Lithium Disilicate or Zirconia.
* Preparations should be cut with classic shoulder design for vertical support for optimal transition of light into the tissue.
* IPS e.max requires adequate room palatally, lingually, occlusally with 2mm clearance for occlusal strength.
* Buccal requires adequate thickness for porcelain build up and colour.
* Bridges are ideally restricted to three unit spans.
* A requirement for bridges is to allow sufficient clinical height for adequate connectors. A connector should be approx. 3mm to 4mm in height.
* IPS e.max offers superior aesthetics over conventional porcelain bonded restorations, although sometimes the strength can be compromised.
* Use IPS e.max on Zirconia for long span bridgework as an alternative to porcelain bonded bridgework.
* In conjunction with Zirconia abutments, IPS e.max offers superior restorations for implant applications.

Guidelines for IPS e.max full contour or Facial Veneers:

* Can be used as full contour stained where space is at a minimum, or fully layered where space is available.
* Where a form change is required, "open or clear the inter-proximal areas" so the IPS e.max veneer can re-contour inter-dental areas to create new tooth forms.
* If no form change is required leave inter-dental contacts intact to maintain tooth enamel for bonding.

Guidelines for IPS e.max Inlays:

* IPS e.max inlays, onlays, one, two or three surface either clear glazed or stained offers excellent aesthetic results.
* Avoid cutting internal sharp corners within internal boxes as this may create pressure points or increased friction on cementing.
* Consider that this pressure may increase or cause micro-cracks to propagate within the ceramic or the tooth structure.
* For internal box cutting use a round nosed diamond or tungsten cutter not a square tipped.
* Avoid long bevels as these may distort while firing the ceramic. Cut bevels at thirty degrees and 1.mm in length maximum.
* Consider how the margin will help support the ceramic and ensure a correct sealed closure.

ZIRCONIA

Zirconia has changed the face of dentistry in a way that years past was only a dream. This material can be fabricated into a variety of dental solutions that brings aesthetics and tremendous strength that challenges metal based solutions. Manufactured by technology that delivers unquestionable fit, the latest developments have solved many of the earlier issues related to translucency, colour and light reaction. In its present development Zirconia offers outstanding quality restorations for a wide range of dental procedures, complete reconstructions and implant configurations that are virtually impossible to create by traditional methods.

IPS e.max in our opinion is the softest and most aesthetic solution when using Zirconia for your patient's treatments. IPS e.max overlaying ceramic has a low firing temperature which pays dividends in reducing stress and brittleness usually associated with the Zirconia higher fusing alternatives. Our guidelines below will help you along with how and where this material can be used.

It simply creates superb quality in all respects of its use.

Overview when using Zirconia

* Milled Zirconia offers strength values between 900 to 1100 Mpa.
* It is extremely strong but is more expensive as a restorative option.
* Can be prescribed for cases with little vertical dimension.
* Keep in mind, - Zirconia is abrasive in it natural form when used as a bite stop or full Monolithic applications.
* Always cover Zirconia with layered ceramic where possible.
* When Zirconia is exposed to opposing dentition make sure it is completely polished after adjustment by using diamond polishing pastes or diamond polishing wheels which ensure a good smooth contact with opposing dentition. This reduces abrasion.
* Zirconia as a material is guaranteed for ten years against breakage by the manufacturers.
* Five axis scanning allows today, tremendous design possibilities and milling options.
* Try and avoid undercuts near margins when preparing.

Guidelines for Crowns and Bridges

* Ideal material for all crown indications anterior to posterior.
* More expensive than porcelain fused to metal or IPS e.max.
* Where aesthetics and very close colour matching is required, preps need to accommodate an allowance for 0.3mm for the Zirconia coping on all surfaces.
* A good selection of shoulder porcelains are available to colour match marginal transition to facial tooth surfaces when required.
* For anterior bridge work where bite and leverage issues are concentrated, consider connectors being thicker than metal to increase strength.
* The IPS e.max overlaying ceramic is easy to correct and polish in situ.
* Available in all commercial shades.

Guidelines for Large Reconstructions:

* The software allows for pre-diagnosis waxing to be scanned and copied into the design phase.
* The software allows for complete internal design if preferred.
* Can be milled in one piece up to twelve unit spans, cement retained or implant supported.

Guidelines for Implants:

* Excellent in the design phase to evaluate implant bed contouring and custom abutment design.
* Design issues can be communicated to the dental office for evaluation, approval or discussion.
* Excellent fit to all types of clinical implants.
* Two part Implant solutions are possible on difficult case designs.
* Excellent material to fabricate primary telescopes for removable dentures.
* Complete fabrication of fixed or removable Zirconia bars are possible for fixed or removable Prosthetics.
* Complete Prettau (ZirconZahn) one piece reconstructions are possible from pre-set-up templates.