Should I keep the residual root of the tooth? How to keep the root? | Micro Health

In clinical work, problems caused by residual tooth roots are very common. Residual root refers to the crown of the tooth that has been completely lost, leaving only the root part. There are two main reasons for residual tooth roots. One is caries, which is commonly known as tooth decay, and the other is trauma, where the crown is broken, leaving only the root of the tooth buried in the bone. Residual tooth roots may cause a variety of problems and need to be treated in time.

Figure 1 Caries-development of residual roots

Figure 2 Clinical photos of residual roots

As one of the main causes of residual roots, dental caries has become a common oral problem for Chinese residents. Data from the Fourth China Oral Health Epidemiological Survey Report show that people in the 35-44 age group have an average of 4-5 dental caries, people in the 55-64 age group have an average of 8-9 dental caries, and people in the 65-74 age group have an average of about 13 dental caries, which shows the great impact of dental caries on oral health.

Below I will share with you the knowledge about the harm of residual roots and how to treat them, hoping it will be helpful to everyone.

If you have oral problems with the stump , you must seek medical attention immediately. Even if the stump is not painful for the time being, it does not mean that there are no three hidden dangers listed below (biological, functional, and aesthetic hazards).

The first hidden danger of residual roots is bacterial infection . If residual roots are not treated, the pulp cavity and root canal of the tooth will be exposed to the external bacterial environment. Bacteria can reach the root apex along the root canal, causing an inflammatory reaction around the root apex, which will cause toothache and may even induce other diseases that affect the whole body.

The second hidden danger of residual roots is that they can cause functional problems . If a tooth is missing, the efficiency of chewing will certainly be affected, which will bring about problems with nutritional intake. Studies have shown that elderly people with poor dentition have significantly lower dietary diversity, as shown by a lower frequency of consuming fresh fruits, fresh vegetables, meat, fish and other foods, and poorer nutritional status. In addition, residual roots can cause "mouth leakage" and affect pronunciation function.

The third hidden danger caused by residual roots is that the dentition will become unsightly . Our teeth rely on each other, just like they are lined up. If a tooth has no crown and only residual roots are left, the adjacent teeth on both sides will move toward the position of the residual roots, and the opposing teeth will also gradually grow longer, affecting the alignment of the dentition and causing aesthetic problems.

Figure 3 Harm of residual roots

There are conditions for protecting the residual roots

Figure 4 Root residue processing flow

If the doctor determines that the remaining root is inflamed, loose, or too short, it is usually removed and the bone is allowed to recover before further treatment such as dental implants, removable dentures, or fixed bridges. If the doctor determines that the remaining root is in good condition and worth preserving, "root preservation" treatment is performed:

First step: root canal treatment

Root canal treatment can completely remove the infected pulp and then fill the root canal tightly, which can completely isolate the external infection from the root canal, prevent inflammation caused by bacteria, and greatly extend the service life of the tooth. After completing the root canal treatment, it is necessary to observe for about two weeks. If the tooth has no discomfort, the next step of restorative treatment can be carried out.

Second step repair treatment

In order to avoid residual root fracture, restorative treatment is necessary. Here we introduce two commonly used restoration methods: overdenture and telescopic crown.

(1) Overdenture

After the remaining root is sealed, you can consider making an overdenture. The doctor will design a denture with the right shape and size. Since the tooth root is retained, the absorption of the alveolar bone will be slowed down, and the life of the overdenture will be longer. You can also make additional devices on the healthy tooth root, so that the denture will be more stable and the chewing efficiency will be improved.

(2) Telescopic crown denture

Telescopic crown, also called double crown retainer, is a removable denture. The telescopic crown retainer consists of an inner crown and an outer crown. The inner crown is tightly bonded to the surface of the remaining tooth tissue, and the outer crown covers the inner crown surface. When the teeth are needed, the outer crown is worn to meet daily tooth use needs; when not in use, the outer crown can be removed for easy cleaning and maintenance.

Telescopic dentures have many advantages. First, they remain strong after repeated wearing and taking off, and will not damage the surrounding tooth tissue due to friction; second, the outer crown can be removed for easy maintenance. In general, "it is more flexible than fixed dentures and more stable than removable dentures."

Figure 5 Repair methods after root removal

Fig.6 Post-core crown restoration with residual root preservation

Early treatment of caries is very important. September 20, 2023 is the 35th "National Love Teeth Day", with the theme of "Oral Health and Whole Body Health". Oral health is closely related to overall health. "Toothache is not a disease, but it hurts so much." In the early stages, caries only affects the surface of the tooth enamel, and you won't feel toothache when you treat it. However, if treatment is not timely, caries will spread to the pulp and affect the dental nerves. If you treat it at this time, it will "hurt so much". Moreover, the pathogenic bacteria in caries and the harmful metabolites of inflammation will enter the blood vessels, spread throughout the body, and affect the heart, kidneys, central nervous system, etc., bringing more serious consequences.

For the same oral problem, if it can be detected and treated early, the normal function of the oral cavity can be better maintained, while saving more time, energy and money.

Figure 7 Methods of tooth protection and repair at different stages

In addition to daily brushing and cleaning, healthy teeth only need regular teeth cleaning to stay healthy. If small cavities occur, resin fillings, that is, fillings, are required, which can be completed in one visit and are relatively low in cost. However, if they are not treated and develop into large cavities, ceramic inlays will be needed for repair. If further damage occurs, such as dental neuritis and root inflammation, root canal treatment must be performed, followed by crown restoration. Finally, if the disease develops to the point where only residual roots remain, the function of the teeth will inevitably be severely damaged regardless of whether the residual roots are removed or retained. The corresponding treatment plan will require multiple follow-up visits, which will be costly, time-consuming and labor-intensive. In addition, symptoms such as swollen and painful gums and fever may occur during the treatment, affecting normal work and life.

As the old saying goes, "a good doctor treats illness before it occurs." If you can do a good job of daily oral hygiene to prevent oral problems, or treat them early when they first appear, you can ensure the health of your oral cavity and enjoy life with good teeth.

(This article is funded by the Shanghai Science Education Development Foundation's Science Public Welfare Project)

Author: Huang Xia (text), Zhang Yuan (picture)

Instructor: Wang Jie, attending physician of the Department of Oral Rehabilitation, the Ninth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine

Dai Zhaowei, resident physician at the Department of General Stomatology, the Ninth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine