Damaged Tooth Crown Repair in Alexandria
A cap, crown or more accurately a fixed partial denture is the name given to a restoration that replaces the part of the tooth that is above the gumline. Preparing a tooth for a crown has a relatively high biological cost as the removed tooth structure cannot be regrown. However, when a tooth is severely damaged, a crown can be a beautiful and long-lasting solution to restoring a tooth.
Dentistry has been compared to cosmetic (plastic) surgery where the goal is to provide an undetectable end result. Creating a natural-looking, long-lasting, comfortable crown to restore a damage tooth begins with a critical evaluation of what caused the tooth to fail. To achieve an optimal result, many things are considered.
Is the tooth a good candidate for a crown?
On many occasions, patients have presented to our office with a tooth or teeth where decay or trauma has reduced the amount of tooth structure available to place a crown. The term “ferrule effect” has been used to describe the minimum amount of tooth structure above the bone that a crown must be supported by in order to keep the tooth from fracturing. Many times, a crown that has “come off” lacks an adequate 1.5 to 2.0 mm “ferrule”. Approaches to regaining an adequate ferrule include limited orthodontic or periodontal treatment. An indication that a tooth may have an inadequate ferrule would be if a crown unexpectedly falls off. Often the remainder of the tooth is fractured off and remains inside of the crown.
Another consideration when restoring a tooth with a crown is the concept of biological width. Biological width is the space that the body needs to transition from an “inside” tissue such as bone to an “outside” tissue such as epithelium (gum tissue). In his famous paper, Tarnow determined that amount to be 2mm measured from the margin or edge of your crown to the top of your bone tissue. An indication of a tooth that may have an inadequate biological width is red, swollen and bleeding gums where your crown and gums meet. Another cause of these symptoms may be an “open margin” or crown that does not fit tightly to your tooth.
There are many types and grades of crowns. A crown may be made of all gold, porcelain fused to gold, zirconium, porcelain fused zirconium, pressed empress, di-lithium silicate or all porcelain (feldspathic). Which material to choose depends on may factors unique to each patient. Each choice has its benefits and disadvantages. It is important to have a discussion of which material choices best suits your need.
Who makes a crown?
A master ceramist spends years sometimes decades honing his craft. A ceramist is an artist who specialized in creating life-like porcelain restorations that look and feel like teeth. Just as the talent of other types of artists vary widely, the abilities of ceramists vary widely. The best ceramists often come from Switzerland or Japan because of the available training and history of porcelain of their cultures. A high quality custom restoration is an artform that cannot be mass produced by a machine. It may look impressive to have a crown made by a machine while you wait but such a restoration cannot compare to results of a master ceramist. To begin, a machined crown by necessity is milled from a monochromatic block of material. The inability to layer different hues and shades of porcelain give the final result an opaque lifeless appearance. The shape of the crown is also predetermined by the software of the milling machine preventing the reflection of the variation seen in every day people. The fit of machined crowns has gotten much better however.
A level above a machined crown is a creation of a crown by a ceramist who has not undergone the rigorous training that necessary to achieve the level of a master. If the crown is constructed outside of the US, it is important to make sure that the materials used to make the crown and its substructure are of the highest quality. Our ceramist is from Switzerland and has achieve mastery level. He is renowned for the quality of his work which often is on display at cosmetic and aesthetic dental conventions around the world where he presents and lectures on ceramics. With his help, we are able to make beautiful, natural-looking, long-lasting restorations for our patients.
How long does it take to create a dental crown?After the remaining tooth structure is assessed and found to be a good candidate for a crown, fabricating a crown requires at least two visits to our office. Initially, we will remove decay, shape the tooth, take an impression and construct a provisional crown made of acrylic resin or other hard plastic. On the subsequent visit, we remove the provisional crown, cement or bond it into place and then adjust the bite.
Key Benefits of Dental Crowns
- Replaces missing tooth structure of a severely damaged tooth
- Protects remaining tooth structure as in the case of cracked tooth or of a back tooth that has undergone root canal therapy
- Looks and feels like natural tooth
- Fixes functional chewing problems
What are the capabilities of crowns?
Crown and bridgework is a time-tested solution for major dental problems caused by traumatic accidents, caries or wear. Major problems can usually be corrected using these restorations.
In some cases, patients who have unexplained pain from filled back teeth may have hairline cracks in the unrestored part of the tooth. Placing a crown on these teeth can relieve the pain and allow a return to function for these teeth. In front teeth, older fillings can weaken teeth and appear unesthetic due to staining or chipping. Porcelain crowns and bridges are suitable in cases where insufficient tooth structure remains to support porcelain veneers . In back teeth that have undergone root canal therapy, crowns are necessary to prevent breakage. A front tooth that has undergone root canal therapy requires a crown only if significant tooth structure has been lost.