I get scared when I hear the sound of a dental drill. Does filling a tooth really hurt that much?

Author: Yu Qing, Chief Physician, School of Stomatology, Air Force Medical University (Fourth Military Medical University)

Chairman of the Professional Committee of Endodontics of the Chinese Stomatological Association

Reviewer: Li Song, Chief Physician, Beijing Stomatological Hospital, Capital Medical University

Director of the Chinese Stomatological Association

Many people have had a missing tooth or a hole in one, and often do not want to get a filling unless it is absolutely necessary, because they get nervous when they hear the sound of a dental drill and it feels very painful.

Figure 1 Original copyright image, no permission to reprint

In fact, we should have a correct understanding of tooth fillings and should not always be immersed in imagination and fear.

1. Will the tooth filling process be painful?

If the tooth defect does not involve the pulp tissue, the doctor will try to preserve the pulp, which is the dental nerve.

The dental pulp has the function of sensing external stimuli, such as hot, cold, sour and sweet. In addition, the dental pulp also has the function of internal protection. After the tooth erupts, the outer layer of the dental pulp tissue can continuously form a hard tissue protective layer, called dentin.

If the tooth loses its pulp, it will lose its nutritional supply, which will cause the tooth to become brittle and weaker. Many patients have to undergo root canal treatment to remove the infection after the dental nerve necrosis. Doctors usually recommend that the treated tooth be protected with a full crown or high onlay to prevent the tooth that has lost its pulp from breaking as much as possible.

When filling a tooth, the doctor needs to remove the diseased tooth tissue. When the dentin is affected, there may be some sensitivity. The doctor can minimize this uncomfortable feeling from a technical level by controlling the cleaning technique. If the disease does not affect the pulp, there will usually not be strong pain.

If the tooth lesion involves the pulp, treatment under anesthesia is required. Commonly used anesthesia methods include local block anesthesia, local infiltration anesthesia, and computer-controlled painless anesthesia. By combining the use of nitrous oxide, painless and comfortable treatment can be achieved, so there is no need to worry.

2. What materials are used for filling teeth?

More than a hundred years ago, the material used for tooth fillings was silver-mercury alloy, a metal material with the advantages of good strength and special wear resistance.

However, there are also obvious disadvantages. First, the color is not beautiful. Second, it has no adhesion to tooth tissue, and the affected tooth must be ground into a specific hole shape to fix the material, resulting in more tooth tissue being removed than when using other materials. Third, the biocompatibility is relatively poor.

Therefore, most hospitals no longer use silver amalgam for dental filling treatment.

Subsequently, scholars developed a composite resin material that has many advantages:

First, it has good aesthetics, and the color of the material can perfectly match the affected tooth, and even be indistinguishable from the real thing. In many cases, the affected tooth cannot be seen after the filling. Secondly, the composite resin is adhesive to the tooth tissue, so much less tooth tissue needs to be removed than when using silver-mercury alloy. Thirdly, the composite resin material can solidify under light, so it is highly operable and the doctor can operate more calmly.

The only drawback is that the strength of the composite resin, that is, its wear resistance, is slightly worse than that of amalgam.

Figure 2 Original copyright image, no permission to reprint

In the past decade, with the continuous development of materials science, especially the emergence of nanomaterials, the mechanical properties of composite resin materials have been greatly improved. The current mainstream direct repair material is nanocomposite resin.

3. Will there be pain or dentin sensitivity after filling a tooth?

You may feel some discomfort for a day or two after a filling, which will gradually subside under normal circumstances. However, if the pain or discomfort lasts for a long time or the symptoms worsen, it may not be normal and you need to have a checkup to analyze the cause.

For example, when a tooth is filled, the dental nerve has already undergone an irreversible inflammatory reaction. The doctor failed to correctly judge the state of the dental pulp and performed pulp preservation treatment on the affected tooth. The pain may be worse after the filling. In this case, root canal treatment should be performed to remove the dental pulp. In addition, in the process of removing caries, improper treatment of the tooth cavity or improper selection of materials may also cause pain. Therefore, if there are long-term discomfort symptoms after a tooth is filled, you should see a doctor for a follow-up examination as soon as possible.

In most cases, dentin sensitivity will not occur after filling and repairing tooth defects. This is because the commonly used filling materials, especially composite resin materials, have good biocompatibility.

Finally, we need to remind everyone that everything is not over after filling a tooth. What is more important is to eliminate the cause, that is, to eliminate the cause of caries. If the cause is not controlled well, even if the tooth is filled well, caries will occur at the edge again.

Therefore, maintaining good oral hygiene and having regular comprehensive dental checkups are essential to maintaining oral health.