What is a crown and why do I need one?
Sometimes when presenting treatment options, I bring up the word “crown” and I get a puzzled look from our patient. I realized that they may have heard of a crown or cap, but they really have no idea what one is and why they would need it. In this column, I will review what crowns are, what they are often made of, what the procedure is like, and most importantly, why you may need one.
To keep things less confusing, I will refer to all types of crowns (inlays, onlays, ¾ crowns) as crowns. Also, the word “cap” is often used, but means the same thing. A crown is a dental restoration that covers most or all of the biting surface of a tooth in order to preserve it from fracture. Once a tooth has a large portion of it replaced with filling material, it often becomes brittle and prone to fracture. Also, some teeth develop large fracture lines or become tender to biting certain foods, which is an indication of fracture. These are indications that a tooth likely needs a crown. Teeth are similar to wood in some ways and years of use and misuse can cause them to split. They also can split off a part of the tooth or they can split right down the middle, which can be a very painful problem. The difficult part for a dentist is knowing which teeth are likely to split, because sometimes highly cracked teeth won’t break but ones with minimal fracture lines split in two. It’s always a judgement call. Often times we take intraoral photos and share them with the patient to let them be a part of the decision making process.
Crowns of the distant past were all made of gold. Gold is a great material but due to cost and modern esthetic tastes, it has fallen out of favor. For many years, most offices used a combination of gold alloy and porcelain fused to metal for crowns, while all-ceramics have slowly made an appearance on the scene and now dominate the market. Porcelain fused to metal crowns were great but they often left dark lines under the teeth if the gum receded. Modern ceramics are incredibly strong and can be bonded to the tooth. This allows a lot of dentists the ability to make more conservative preparations.
For the procedure, the patient will need to be numbed with local anesthetic and then the tooth is prepared by removing parts of it with a drill. This has two purposes: to removed damaged and cracked tooth structure, and to create space for the crown. All materials need a minimum thickness of material. Afterwards, a digital or physical impression is taken. Next, either a temporary is made and the case is sent to a lab, however some systems allow production of the crown in-office through a CAD/CAM system. Crowns are made right on the spot with no temporary crowns.
Lastly, crowns are needed to restore teeth, and today, are sometimes stronger versions of what they started as. Many people are keeping most of their teeth their entire lives which may mean the teeth need to be in the mouth 80 years or more. This will likely be over 29,000 meals with the same teeth. If you add tooth structure lost to filling material, and clenching and grinding, the cumulative stress on teeth is more than most can take. Crowns are a great option to keep a tooth functioning your whole life.
Dr. Brian P. Hall General Dentistry is located at 1180 Resurgence Drive Suite 300, Watkinsville, GA 30677 and can be contacted by phone at 706.549.8737. www.halldental.com
