When can YOU watch vs fill the tooth?

One of my jobs in dentistry is to let patients know what problems they have in their mouths. Most of the time this means telling a patient they have cavities or decay that need to be filled. Many patients ask me if the cavity is one that needs to be filled or can it be “watched”. So how do we determine if a cavity needs to be filled or watched, especially when the cavity is between the teeth?

Tooth Anatomy

Before we cover that, let’s take a brief look at the anatomy of a tooth. Teeth have 3 main layers: Enamel, Dentin, and Pulp tissue. Enamel is the hard white layer on the outside of the teeth that we can see. Enamel is fully mineralized and has no feeling. Dentin is the underlying layer that is mostly mineral but has some tubes that the pulp tissue runs through giving this layer feel. The pulp is the innermost layer of the tooth where the nerve and blood supply of the tooth live. 

We can “watch” and area if the cavity is less than ¾ of the way through the enamel. When a cavity is not past the ¾ mark we can stop the growth of the cavity with good oral hygiene, reducing sugar intake, and increasing the use of fluoride. This will help the minerals in our saliva re-harden that area. A filling needs to be done when a cavity extends over ¾ of the way through the enamel layer of the tooth. Once a cavity has made it this far into the tooth it cannot be halted or reversed, it will only get bigger over time. We can determine approximately how large a cavity is with a good x-ray. 

Dental Filling

In this example, the second to last tooth in the upper right of this x-ray has a small cavity on the back side that is less than half way through the enamel. This looks like a small grey triangle of half circle. On the front side of the same tooth, you will see a grey triangle that extends completely to the second layer (dentin) of the tooth. For this tooth, we would do a filling on the front side and monitor the backside.

Just like anything in dentistry, this rule is not 100% hard and fast. We have to look at the whole mouth, not each tooth individually. This means we may choose to fill some of these smaller areas if you are a high cavity risk patient. This means you have multiple other cavities or a history of new cavities forming quickly. This x-ray is of a patient that is at a high cavity risk. As you can see there are multiple teeth with grey triangles between the teeth. This is an example where we may choose to also fill some of those smaller areas. We may also opt to watch a slightly larger area if it is the only one in your mouth and you have a history of little to no other cavities. 

Hopefully, this gives you a little insight into how we make our treatment decisions. The first step to having a healthy mouth is getting an exam. So please give our office a call to make your appointment. I look forward to hearing from you!