Crowns are permanent, non-removable restorations that either partially or completely cover an individual tooth or multiple teeth. Typically a crown is made on a heavily restored or root canal treated tooth to prevent it from possible future fracture. In certain situations where the biting surface of a posterior tooth is badly damaged but the cervical portion of the tooth is still intact and unfilled, then a more conservative partial crown which covers the biting surface but which does not extend all the way down to the gum line, can be fabricated – such a restoration is called an onlay or a ¾ crown. Dr Willoughby likes using this type of restoration because it conserves natural tooth structure and is a very durable restoration. Onlays can be made from gold or porcelain but, unless the patient expressly asks for gold, we tend to limit the use of gold onlays to posterior teeth which cannot be seen when the patient smiles.
Full Coverage Crowns
Full Coverage Dental crowns are typically placed to:
- Restore a tooth with a broken cusp or heavily worn tooth
- Provide coverage for a cracked tooth
- Restore a tooth that has a large amount of decay
- Cover a dental implant
- Cover a severely discolored tooth
- Build up a misshapen tooth like a peg shaped lateral or microdont.
- Replace hypo-calcified tooth enamel
- Realign a mal-positioned tooth visa vie ‘instant orthodontics’
- Splint two or more teeth together for increased anchorage and periodontal support.
The teeth to be restored with a crown are prepared by the Dentist using his hi speed hand-piece. An experienced general Dentist such as Dr. Willoughby pays particular attention to developing the internal and external retention of his crown preparation as well as smooth continuous even margins (which is critical to the ultimate fit and durability of the crown). Sometimes when there is a lack of clinical crown height Dr. Willoughby will suggest the use of his Lasers to help re-contour the tooth and expose more clinical crown height. An impression is then made of the tooth preparation created by the Dentist and a stone model of the patient’s mouth is then made from these impressions. The restoration is then created on the model by a dental lab technician.
Before graduating as a Dentist Dr. Willoughby was trained as a dental lab technician so, Dr. Willoughby and his staff are very proud of the beautiful work their dental lab produces and will always take the time to show his patients the details of his crown preparations and the fit of these restorations on the working models. The accuracy of the Dentist’s preparation and the dental lab technicians work cannot be over-emphasized because this is, in large part, what will determine the long term success of your crown and bridgework. Many of you have seen Dr. Willoughby show you these models before your crowns have been permanently cemented onto your teeth.
At the Bayview Dental Studio, Dr. Willoughby and his team take great pride in designing dental crowns to closely match the shape and color of your surrounding natural teeth. Dr. Willoughby and his team will always check the marginal fit of your crowns by taking a digital x-ray to ensure the fit is perfect before it is cemented to place.
“Dr. Willoughby will never permanently cement a crown or bridge until we are completely happy with the fit and you are completely happy with the shape and color.”
Below is a perfect example of an All Porcelain E-Max crown placed by Dr. Willoughby.
There are various materials which can be used to make crowns but, in most situations, Dr. Willoughby recommends bonded porcelain crowns for his patients rather than metal reinforced crowns due to the superior aesthetics and marginal integrity of a bonded ceramic crown. Dr. Willoughby has been placing E-max crowns since they first became popular in Canada in 2004-2005 and since this time he has placed literally thousands of bonded porcelain crowns. For anterior crowns where the aesthetic demand is high Dr. Willoughby has his lab fabricate an E-max pressed porcelain crown and then has them perform an “incisal cutback” so that more vital, translucent layer of porcelain can be built up over the lithium disilicate core. For posterior crowns, E-max pressed porcelain crowns made of pure lithium disilicate can provide incredible strength and durability and can be readily custom stained and characterized to blend in beautifully to surrounding natural teeth. The aesthetic results and functional durability of the E-max material is second to none!
For further images of crowns and onlays crafted by Dr. Willoughby please visit our Smile Gallery section.
If you are interested in replacing your old large fillings with new state of the art E-max all porcelain crowns we would be happy to hear from you so please feel free to contact our Cosmetic Dental studio in the South Surrey area by calling 604.541.1800.