Thursday, November 7, 2013

Why Does a Tooth Hurt After a Filling?

It's not normal for a tooth to hurt after a filling is placed. Unfortunately, it does occur on occasion. When this happens, there is almost certainly something that has caused the discomfort. We have to put on our detective hats and figure out the true cause of discomfort. There are many potential causes of tooth discomfort after a filling is placed. Here are a six potential reasons:

1. A "high" Filling

This just means that the bite is too high. In other words, there may be too much filling material that causes the opposing tooth to hit the filling prematurely. This causes excessive pressure on the tooth and can certainly cause discomfort. Usually, this is quite simple to diagnose. If the pain is elicited by biting into the filling, then it is likely that the filling is a little too high. You may also experience cold sensitivity on the tooth.

When a patient is numb, sometimes it is difficult to assess the bite. After the numbness wears off, it is much easier to assess the bite. If the bite feels funny after the numbness wears off, do not assume that you will get used to the bite. You won't. It will start to hurt and cause bigger issues. Fortunately, a high filling is easy to correct. All that is necessary is to grind the filling down slightly.

2. Uncured filling material

A special light hardens the filling material.
Tooth colored fillings usually have a paste like consistency until it is "cured" with a special light. This light initiates a reaction and causes the material to become very hard. If for some reason, there remains material that hasn't solidified, the tooth will become sensitive to cold and biting. You may now be thinking "hey, those are the same clues as the "high filling". You're absolutely right...they are the same. There are ways to distinguish between the two. In this case, there may also be unprovoked pain. In other words it just hurts even when not biting or eating/drinking something cold. Fortunately, this is easy to correct as well. Applying the special light to the filling will usually resolve the problem. If it doesn't, then replacing the filling should solve the problem.

3. Trauma from the procedure

When any work is done to a tooth, it is a traumatic experience for the tooth. Sometimes the nerves inside the tooth get irritated. When this happens, the tooth becomes hypersensitive to cold. Again, you may wondering "hey, just like the previous two problems". Again, you are absolutely right. In this case though, there should not be any discomfort when biting. The good news is that this problem will usually correct itself within a few days. An anti-inflammatory medication such as Ibuprofen will reduce the inflammation within the tooth and will therefore also reduce any discomfort.

4. Exposed Root Surfaces

Exposed root surfaces on multiple teeth.
When the gums recede past the necks of the teeth and exposes the root surfaces, there can be some cold sensitivity. In many cases, this can be resolved with a desensitizing toothpaste such as Sensodyne.

If you have exposed root surfaces that weren't cold sensitive prior to the filling being placed, but now are, then it is likely that the inflammation caused by the procedure on the tooth will make the tooth very sensitive to cold. Just like in the previous example, Ibuprofen can help. Even if medications aren't taken, this problem will usually resolve itself within a couple days.

5. Open Margins

Open margins
This means that there is a gap between the tooth and the restoration. because of this, there is exposed tooth structure. Exposed tooth structure tends to be very hypersensitive to thermal changes. If this is the cause of the sensitivity, then by simply filling in the exposed tooth structure should resolve the problem.

If the margins are left open, then the tooth will develop decay again right at the interface between the tooth and restoration. It is imperative that the margins are completely sealed.

6. Cracked Tooth

Obvious fractures.
I've mentioned in previous blogs that I don't place any metal fillings. I haven't placed one since 1997. I've seen countless teeth that have fractures that are directly attributable to these metal fillings. Read my blog on metal fillings. A cracked tooth is sometimes a death sentence for a tooth. If the fracture stays above the gumline, then we could most likely save the tooth. However, if the fracture has spread below the gumline, there is nothing we could do to salvage the tooth.

In many cases, we often can't even see a fracture but know it is there. A good clue is that the tooth hurts only when biting a certain way. It doesn't always hurt when biting, but when the direction of the force is applied in such a way to spread the fracture, pain is elicited.

There are more reasons than these six, but these are the most common. If problems persist for more than a few days, have the tooth evaluated to determine what the problem is.

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1 comment:

  1. To have a healthy looking teeth brushing alone is not enough, eating healthy food and proper oral hygiene are some of the things you need to do to prevent any tooth problems.
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