Metal ceramic

All-ceramic anterior restorations can appear very natural. Unfortunately, the ceramics used in these restorations are brittle and subject to fracture from high tensile stresses. Conversely, all-metal restorations are strong and tough but, from an esthetic viewpoint, acceptable only for posterior restorations. Fortunately the esthetic qualities of ceramic materials can be combined with the strength and toughness of metals to produce restorations that have both a natural toothlike appearance and very good mechanical properties. As a result they are more successful as posterior restorations than all-ceramic crowns. A cross section of a ceramic-metal anterior crown is shown in Fig. The cast metal coping provides a substrate on which a ceramic coating is fused. The ceramics used for these restora­tions are porcelains, hence the common name, porcelain-fused-to-metal restorations. These ceramic-metal restorations are highly popular and are used for most of the crown and bridge restorations made today.

 Cross section of a ceramic-metal crown showing a sold alloy or base metal copins, the opaque body (dentin), and enamel ceramic layers.

High fusing temperature of the alloy. The fusing temperature must be substantially higher (>100° C) than the firing tem­perature of the ceramic and solders used to join segments of a bridge.

Low fusing temperature of the ceramic. The fusing temperature must be lower than ceramic used for all-ceramic restora­tions so no distortion of the coping takes place during fabrication.

The ceramic must wet the alloy readily when applied as a slurry in order to pre­vent voids forming at the interface. In general, the contact angle should be 60 degrees or less.

A good bond between the ceramic and metal is essential and is achieved by the interactions of the ceramic with metal ox­ides on the surface of metal  and by the roughness of the metal coping.

Compatible coefficients of thermal expan­sion of the ceramic and metal so the ceramic does not crack during fabrica­tion. The system is designed so the value for the metal is slightly higher than for the ceramic, thus putting the ceramic in compression (where it is stronger) during cooling  

Adequate stiffness and strength of the alloy core. This requirement is especially impor­tant for fixed bridges and posterior crowns. High stiffness in the alloy reduces stresses in the ceramic by reducing deflection and strain. High strength is essential in the interproximal regions in fixed bridges.

High sag resistance is essential. The alloy copings are relatively thin; no distortion should occur during firing of the ceramic or the fit of the restoration will be compromised.

An accurate casting of the metal coping is required even with the higher fusing tem­perature of the alloy.

BPS Precision Dentures

Ivoclar BPS premium quality dentures instill confidence and provide optimum function while eating, speaking or laughing.

With sophisticated instrumentation and techniques, all your facial information is recorded to recreate the character of your smile and restore the natural contour of your lips and facial muscles.

                The Ivoclar Transferbow

The Facebow (Transferbow) bite registration registers, analyzes the correct height of the bite and reproduces the jaw movements. This data is then transferred to the Stratos 200 articulator, which replicates that movement of your jaw and creates your smile line.

Premium Ivoclar denture teeth are used to reflect light through several layers that mimic natural teeth. The quality materials resist wear, chipping and staining. Ivoclar Viviodent teeth, Anteris Posteris, and Vivoperl Porcelain teeth are made from high quality cross-linked acrylics and porcelains that resist excessive wear, stains, chips and breakage. This high quality material will maintain the natural shape of the teeth so that proper cutting and chewing of desired foods can be maintained.

State-of-the-art equipment is used to form the denture base. Not all dentures are fabricated using the same materials or techniques. The acrylic used for the pink tissue portion of a denture will shrink when it is processed and can cause inaccuracies in the fit of the denture to your mouth. This shrinkage can cause sore spots and movement during eating and speaking. Fortunately a revolutionary system SR Ivocap, has been developed that completely compensates for the processing shrinkage of the denture base material. The injection technology used in the SR Ivocap system is considered the state-of-the art in denture processing. The accuracy of the process results in a denture that will provide you with the best fit possible. You can eat, talk and smile with confidence with your SR Ivocap denture.

SR Ivocap Advantages:

Comfort - reduced irritation to the gums.

Strength - extremely dense material reduces the chance of breakage

Cleanliness - non porous surface greatly lessens odor causing plaque and bacteria

Fit - non irritating and comfortable to wear - no denture adhesive needed

Health - eat virtually any food

Esthetics - natural looking so you can smile, speak and laugh with confidence

Bio-compatible - will not distort taste, stain, or collect odors or irritating bacteria. The result is a better fitting, more comfortable restoration that requires fewer adjustments.

Porcelain Veneers

Porcelain veneers, or “dental veneers,” can change the appearance of teeth that are chipped, worn, stained, crooked, or generally damaged. A porcelain veneer acts as a thin shell, covering the surface of a tooth. Porcelain veneers are bonded directly to the front of teeth with adhesive cement for an immediate improvement in the shape and color of each tooth. The color of porcelain veneers can be matched to the color of a patient’s teeth. And because dental veneers are made of porcelain, a glassy composition, they are resistant to staining. Porcelain veneers reflect light in a similar way as tooth enamel, and can be buffed and shaped to look just like natural teeth.

The entire porcelain veneer cosmetic dentistry procedure normally takes only 2-3 visits to our dental office .

In the first visit the patient will discuss the procedure with the cosmetic dentist. During this initial consultation the dental patient will have the opportunity to discuss how the final smile should look. Please feel free to bring pictures of ideal smiles to your initial consultation! During the second appointment the teeth will be prepared for the porcelain veneers and a mould will be made of the teeth. In the final appointment porcelain veneers, designed specifically for the patient, will be placed on the teeth.

Porcelain veneers have become popular in the time that they have been available because they are natural looking, durable, and long-lasting. To learn more about porcelain veneers, please contact us today.

Dental Veneer Aftercare

While it may take a little time to get used to the appearance and feel of porcelain or composite veneers, there is no special care needed. You should not bite any objects that can cause the dental veneers to come off. You should continue to maintain your oral hygiene program, which includes thorough brushing and flossing.

Advantages of Dental Veneers There are many advantages of using porcelain veneers as a tooth restoration procedure. You can achieve a very good cosmetic appearance with a minimal amount of tooth preparation. This is not often the case with dental crowns. Composite veneers are the more popular of the two, as porcelain veneers have a tendency to fracture. Composite veneers are also thinner and therefore require less tooth structure removal before the veneer is applied. But, the advantage of using porcelain veneers over composite veneers is that porcelain veneers are more durable and less likely to stain, but it is still recommended that a person avoid excessive consumption of foods and drinks that tend to stain, such as coffee, tea or wine. If you tend to grind or clench your teeth, a porcelain or composite veneer can chip or fracture. When a dental veneer breaks, it cannot be repaired. The porcelain or composite veneer must be completely replaced.

Zirconia Crowns

Zirconium crowns and bridges are so strong they can be used anywhere in the mouth. Zirconium crowns can withstand the biting pressure of the front teeth as well as back teeth grinding.

The look of zirconium crowns and bridges is so close to natural teeth that it is hard to tell the difference and it is this quality which makes it very useable within dental work. Zirconium crowns can be fixed using traditional dental cements.

Zirconium crowns have quickly become the preferred material for dental crowns. Zirconium is a very strong substance that can endure wear and tear of everyday use. When looking at Zirconium crowns from an aesthetic point it is clear and very similar to a natural tooth and reflects light the same way. This may be important if your new crowns are on the front of your mouth and it is particularly relevant in cases where the crown will be seen next to the natural teeth.

Porcelain is the conventional material used for the new crowns however, Full porcelain can chip or break. This is overcome by making the crowns from the metal, in this case metal zirconia, then merge the porcelain on the outside. Zirconia metal gives the strength while the porcelain gives the appearance of a normal tooth. Zirconium crowns allow light to pass as a normal tooth would and that gives a natural look, unlike other metal cores that are block the light.

Zirconia Crowns

What are Zirconia Crowns?

Zirconia has been used in orthopedic surgery for years, and has proved to be highly bio-compatible. In Europe, Zirconia implants have been used for years to provide the ultimate in bio-compatability. Although titanium is incredibly strong and resilient, and has a good history of bio-compatability, it is not completely inert. With many millions of titanium implants a small minority of patients have suffered side effects from the effects of metal in the body.

Titanium constantly releases metal ions into your body, and this constant exposure in certain individual sometimes triggers side effects which may include soreness, inflammation, allergies, and even autoimmune disease. Metal in the mouth also creates a battery effect - the saliva conducts the flow of electricity from one metal pole to another.

Now, the Zirconia manufacturers have worked on new crowns that are custom milled from solid blocks of Zirconia and baked at extremely high temperatures so that the completed crown is pretty near unbreakable. Zirconia is 100% biocompatible. It is inert, and the body does not reject zirconia so you don’t have to worry about allergies or adverse reactions.

Zirconia Crowns have several advantages of both traditional Gold Crowns and Porcelain.

Although Gold Crowns are well tolerated, last long and are a good technical choice, many consumers much prefer to have a natural effect that blends into the overall smile. Many also don't want metal in their mouths.

In most cases the choice will be between a Porcelain Crown and a Zirconia Crown.

Zirconia Crowns have several advantages of standard Porcelain crowns.

Strength and Longevity: Zirconia is virtually indestructible whereas Porcelain crowns are prone to chipping. Crowns have a lifetime of around 10 years. Zirconia should last a lifetime.

Cosmetic: Have you ever seen people with a large unsightly black line above their gums? Up until recently most crowns are Porcelain which is Fused to a Metal base. Over time, the metal begins to show more and more and the restoration can look opaque and monochromatic, with the tell tale dark grey line at the crown join.
The Zirconia Crowns not only look more translucent, but are much stronger than the Porcelain fused to the Metal posts. The Zirconia crowns are milled from a single block of crystal and can be up to five times stronger than a porcelain / metal fuse.

Less tooth Removal: In cases where their is not much room for porcelain build up - for example if an tooth abutment is already quite bulky, a Zirconia Crown can be used because if provides more strength in less volume than a porcelain crown.