By Dr. Matthew Weekes
July 3rd, 2013 Edition
A crown commonly called a cap is a dental restoration that is placed over a tooth that is lacking in natural tooth structure. This may be the result of cavities, fractured off segments, or severe wear and tear. Some teeth erupt into the mouth underdeveloped as is often seen with peg shaped upper lateral incisors. A crown is often used to transform these teeth to a natural form and size.
To restore small defects tooth matching bonding resins are used, but they are not suitable to restore the form and function of extensively compromised teeth. A crown is an excellent restoration in this case. It is fabricated to look and function like a natural tooth with ideal anatomy. It is made either of very hard durable porcelain as is often the case for restoring the four front teeth in either arch, or porcelain fused to metal. The posterior teeth which require more resistance to wear are usually made with porcelain fused on the top of a semi-precious metal.
All teeth that have had root canal treatment should be crowned. As these teeth have no vital tissue, they become more brittle as time goes by and hence are more susceptible to fracture. By placing a crown on the tooth soon after the root canal therapy is performed, the strength of the tooth is greatly increased and the chances of fracture is very unlikely.
A bridge is a fixed prosthesis shaped like a single tooth or several natural teeth and used to replace a single missing tooth or multiple missing teeth. It is attached and supported by crowns that are placed on the prepared teeth at both ends of the vacant space. Bridges like crowns are aesthetically pleasing and restore the ability to chew your food efficiently. Bridges can either be supported by natural healthy teeth or by implants. The advantage of a bridge over a denture is that you do not have to take it out at night and it preserves the soft tissue and bone around the teeth much better than a denture. However very often there are several teeth missing and the treatment of choice could be a combination of bridges and partial dentures, a partial denture alone, or a complete full denture if no natural teeth are present.
A discussion with your dentist will determine the best treatment plan for you and the various alternatives to treatment.