Hello everybody. My name is Dr. Penny Planzos. I'm a prosthodontist and today I'm going to be answering a couple of questions about teeth and tooth decay.
What does tooth decay look like?
Tooth decay can be seen either clinically or radiographically. When we're doing a dental exam, we're doing a checkup exam. We feel with an instrument all the grooves of the teeth, and we feel for anything that is sticky. We also look for parts of the tooth that are discolored or shadows in between the teeth. We also take X-rays, usually once per year, and that allows us to see if there's tooth decay in between the teeth. When we're looking at an X-ray, we can see the three layers of the tooth: the outer layer, which is the enamel; the inner layer, which is the dentin; and then all the way in the center, there is the pulp. When we have tooth decay on an X-ray, we see a shadow or a triangle that shows demineralization from the outer enamel into the inside of the tooth, which is dentin.
What is the main cause of tooth decay?
Tooth decay is basically bacterial in origin. What that means is we have the breakdown of food and carbohydrates in our mouth, and when bacteria is not removed from the teeth, plaque starts to build up. The enamel, which should be hard, becomes softer, and bacteria eats away at the enamel, making its way into the inner surface of the tooth, which is softer. Once it reaches the inner surface of the tooth, the bacteria can spread and eat away more quickly at the inside of the tooth.
What are the stages of tooth decay?
Tooth decay starts as enamel demineralization. The enamel starts to break down and soften. As the tooth decay process proceeds, the decay goes from the outside of the tooth to the inside. If untreated, the decay can make its way into the pulp, which is the nerve of the tooth and should be a sterile environment. Once bacteria gets into the nerve, the tooth becomes infected, and you can start to feel pain and infection, essentially needing a root canal.
What are the symptoms of early tooth decay?
Interestingly, early tooth decay doesn't have many symptoms. When there is early tooth decay and the decay is shallow inside the tooth, patients often don't even know the tooth is decayed. We can catch early tooth decay during six-month recalls and checkup exams, and when we see decay just starting, we can sometimes remove it without even numbing the patient. We open up the tooth using a burr and a dental drill with lots of water, remove the decayed tooth structure until we reach solid tooth structure, and then fill it with a resin, which is a composite material. We don't use any metals, and we form the shape of the tooth, adjust the bite, make sure the tooth has nice contours, is smooth for flossing, and is polished well. That's a filling.
Can a cavity heal on its own?
Not really. When you have a cavity, and you have incipient decay, meaning that demineralization is within the enamel and has not reached the inside of the tooth, that enamel can still be arrested. This means you can prevent it from getting larger with proper brushing, flossing, and oral hygiene. When we see cavities that are very small, especially on X-rays, we advise our patients to floss well in the area and brush thoroughly to hopefully prevent it from getting larger. Once the decay process has reached the dentin, the second layer of the tooth, it cannot heal on its own, and intervention is needed because it will spread quickly, potentially causing the need for a root canal or even tooth loss.
How do you fix tooth decay?
You fix tooth decay by removing it. Tooth decay is very soft; it's leathery, black, brown, sometimes red. You need to open up the tooth, numbing it depending on where the decay is. Using a dental high-speed handpiece and a burr, you remove the affected tooth and get to solid tooth structure, then bond a resin filling in the tooth. If the tooth has severe decay, where the decay process has taken over, a bigger restoration like a crown may be needed to protect it. If decay has spread into the nerve, a root canal may be required, necessitating a visit to a specialist. In cases where decay gets severely bad and cannot be saved, it may require crown lengthening or even extraction.
Is a cavity too late if it hurts?
Some people have a higher pain tolerance than others. Once a cavity starts to hurt, it's likely closer to the nerve. It's a good idea to come in for regular checkups or see your dentist whenever a tooth is hurting because we can take a look and hopefully catch the decay before it gets too far, requiring more than just a filling.