simple to complex dental makeovers
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Don't let an easily identified crown ruin your image. At New Age Cosmetic Dentists, we believe in crowns that look natural and natural-looking crowns, like natural teeth, must transmit light. Ordinary porcelain fused to metal (PFM) crowns can't do that.
 
Writer, Catherine Lim. Obviously fake crowns/bridges can spoil a good picture even if you're not a celebrity
A crown is like a cap that goes over a tooth preparation.
Sometimes, when a tooth is very heavily restored, its multiple fillings may not look good or last long because even the strongest filling materials have their limitations.
The most durable solution for restoring badly damaged teeth is to prepare the tooth for a crown. A crown is some sort of a cap that goes over and embraces every surface of a prepared tooth. The crown not only protects remaining tooth structure, but also restores the original appearance of the tooth.
In the past, gold was the most popular material used for fabricating crowns. Today, it is largely replaced by more aesthetic materials like porcelain. Since porcelain alone is not strong enough, most crowns made of procelain would come with a metal backing. These crowns are very strong, but the metal beneath may show and compromise aesthetics in a demanding patient's front teeth.
In cosmetic dentistry, crowning is also a technique to straighten crooked teeth by first performing elective endodontics, trimming off most of the crooked crown and then rebuilding it in a more aesthetic form. Cosmetic crowns are also usually full ceramic restorations. Examples of ceramics that are very natural-looking and without metal backing are Empress®, Procera®, Cercon® and most recently, IPS e.max.
 Before the launch of IPS e.max in the earlier half of 2006, Empress was the material of choice at our clinic. The material was very aesthetic and hundreds of our patients were pleased with the results. However, we did have a few cases of Empress crowns and bridges fracturing. Owing to the absence of a metal backing, Empress lacks the strength of PFMs. With the new e.max system which is also full ceramic but almost double the strength of Empress, one limitation of full ceramic crowns has just been eliminated. IPS e.max® is the preferred system for cosmetic crown fabrication at New Age Cosmetic Dentists. e.max® is a very new system of crown fabrication which allows a porcelain crown to be made without the metal understructure. Traditionally, porcelain crowns are made by bonding the porcelain to a metal support in a process called Porcelain Fused to Metal (PFM). The drawback is that unlike a natural tooth which exhibits a certain degree of translucency, the metal framework under the porcelain blocks out the light. To the keen observer, the difference in shine and translucency between a natural tooth and a PFM can be quite obvious. While full porcelain crowns (metal free porcelain jacket crowns, PJC) have been done (and are still being done), most have proven to break prematurely. Furthermore, porcelain surfaces are known to wear out opposing natural teeth faster.
  4 emax crowns made a huge difference for this gentleman
  2 emax crowns and composite fillings made a huge difference for this foreign student
If you're unhappy with the opaque, lifeless appearance or the dark line at the margin of your old PFM, you may want to consider changing to Empress® or better still, e.max.
 This patient had 2 emax crowns done. Can you tell where they are? Procedure Unlike direct fillings, crowns cannot be constructed in one visit. The dentist must first take impressions of your mouth to make some study models and also to construct temporary crowns, usually made of resin. Study models help the dentist plan the case. Every tooth is unique and will require the dentist to exercise judgement on where to trim the tooth and how much to trim. For cosmetic cases where tooth positions are changed by crowning, the dentist may have to discuss his plans with the patient before proceeding to the preparation stage.
Teeth which are still vital will feel sensitive when trimmed, so a local anaesthetic is usually given. For root canal treated teeth, anaesthetic is usually not required. Do not be alarmed that quite a large chunk of your tooth may need to be trimmed off. This is to make space for the crown and adequate clearance is absolutely necessary. The thicker the crown, the stronger it is. Once the preparation is complete, the dentist takes an impression of the prepared teeth with a rubbery material. The final crowns will be fabricated on this impression. At the end of the crown preparation visit, temporary crowns are cemented to protect the remaining tooth structure. When the permanent crown is completed in the laboratory (usually takes about a week), the temporary cowns are removed from the mouth to be replaced by the porcelain crown which is then permanently cemented over the prepared tooth. The crowning process is thus completed.
 Crowns can be very simple or complex, depending on the condition of the mouth and the needs of the patient. Mobile teeth are not suitable for crowning. Teeth with bleeding gums will also affect the accuracy of the impression. For cosmetic realignment, a considerable amount of skill and experience are required as the dentist will need to formulate his own plans and prepare the crooked tooth against standard textbook recommendations. Cercon is one material that has excited and disappointed many in the profession. It is probably the only practical solution for long-span full ceramic bridges. Its zirconia core is as strong as metal. However, the aesthetics turn out to pale against other full ceramic systems like Empress and e.max. Some attribute the poor aesthetics to technician incompetence. However, the quality of work seems to be improving in recent years as more labs in Singapore are doing Cercon. From our experience, Cercon only looks good in numbers. We recommend a minimum of 6 units of Cercon crowns and pontics side by side for a natural, consistent look. The colour chosen must also be of a very light shade. Darker shades do not look natural as the Cercon framework is white in colour. Cost Estimation e.max® crowns S$900 each Porcelain fused to metal crowns S$700 each Cercon® Bridges S$1000 per unit How You Can Help Your Dentist 1. After studying your case, your dentist may suggest additional procedures which may not seem to be directly related to crowning. Ask as many questions as you like, but don't dismiss such suggestions as merely additional income for the dentist. Very often, success of the crown will hinge on these additional procedures. For example, the dentist may recommed that you have root canal treatment done before the crowning. This may increase the fees by $200-$500. Don't argue that you don't think it's necessary because you don't feel any pain. Non-vital teeth are sitting time bombs and you don't want them to blow up under an expensive restoration. 2. Be prepared for a long session during the crown preparation phase. Follow all oral hygiene instructions given by your dentist to prevent bleeding gums. Try not to get up to wash or answer your mobile phone too often and allow the dentist to concentrate. 3. Do not reject anaesthesia if you need it. It is very difficult for a dentist to work on a fidgeting patient. During impression taking, the area of operation must be dry. Avoid all unnecessary tongue and cheek movement which will contaminate the field with saliva/blood and give an inaccurate result. 4. When you are choosing the colour of the crown, do not instinctively pick the lightest and whitest shade. In order for crowns to look natural, they must match the adjacent teeth. Respect your dentist's opinion.
5. Colour matching can be tricky if your teeth are not of "standard shade". There could be some natural irregularities which you may wish to duplicate in the artificial crown. To satisfy such requests, your dentist may take pictures of your teeth to show to the ceramist who can then follow the staining pattern of the adjacent teeth. If you're still concerned that the colour may not match, you may request for a visit to the laboratory where the ceramist will do a colour match live - like modeling for an artist. However, with our new 3D Shade Guide, we can now pick a very accurate matching shade even in the clinic.
 6. If temporary crowns were cemented too firmly, the dentist will have trouble removing them when the permanent crowns are ready. That is why temporary crowns are never made strong enough to take heavy biting forces. Freshly trimmed vital teeth will also feel sensitive. Take a soft diet and avoid cold food and drinks when temporary crowns are in place. 7. On the final fit, the dentist will ask you to bite on paper to check your tooth contacts. Bite and grind your teeth as you normally would. Biting in eccentric positions will only send the wrong messages to your dentist. Allow the permanent cement to set for at least one hour before you eat anything. Transient sensitivity will take a few days to a few weeks to subside. Please call 62358316 for appointments or email us |
The Empress® system, unlike its PJC and PFM predecessors, has developed a method of making a ceramic crown without metal that is both durable and aesthetic. Since the crown is made entirely out of ceramic, it can have the same translucency as natural teeth. However, the Empress® is still not as strong as the PFM system in bridge work and in back teeth. Therefore, we still use PFM crowns on back teeth and for longspan bridge work. But for front teeth where aesthetics are the primary concern, we would indicate Empress® crowns. In addition to translucency, Empress® crowns also have no risk of showing metal edges that sometimes appear with PFM. However, with e.max on the market now, it may be wiser to go for the stronger material. e.max even has an aesthetic advantage over Empress. Being stronger, your e.max crown can be made thinner than your Empress crown. Thickness is usually a problem in lower front teeth. We would definitely recommend e.max for lower front teeth.
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