What is the cause of the central cusp of tooth deformity?

Among tooth development abnormalities, there is a phenomenon called abnormal central cusp, which mainly refers to the second premolar of the mandible, the fifth tooth counting from the middle tooth. At this time, the first premolar of the mandible and the premolar of the maxilla often show a protrusion in the middle of the occlusal surface. There will be sharp protrusions, which are prone to fracture and can easily lead to pulpitis or apical root disease.

What is the cause of the central cusp of tooth deformity?

Someone once made such an analogy for the "deformed central cusp": a tooth is like a house, and the pulp tissue inside is protected by walls to prevent infection by external bacteria. However, a deformed central cusp is like a house with a "chimney", but this "chimney" is closed and very thin at the top. If an external force removes the thin seal at the top, or the "chimney" is broken by the wind, bacteria can enter the house through this channel, and the dental pulp inside will be infected by bacteria, accompanied by toothache or sensitivity symptoms.

After symptomatic treatment for the apical periodontitis caused by the fracture of the deformed central cusp, the patient said that the toothache was gone and he dared to eat again. Usually, the deformed central cusp occurs symmetrically. This patient had the same problem with the opposite teeth. Fortunately, there was no pain symptom, and I also treated it accordingly to avoid the problem.

It is worth noting that the deformed central cusp is not easy to detect, and it often causes pulp lesions after breaking, leading to incomplete root development. Therefore, patients should undergo regular oral examinations. Doctors will help detect problems in a timely manner and deal with them properly.

The general processing principle is as follows:

1. For low and blunt central cusps, no treatment is required if the affected tooth is asymptomatic.

2. The high and sharp central apex should be adjusted and ground in batches, with an interval of 2-3 weeks. The thickness of each grinding should not exceed 0.5mm. Apply 75% sodium fluoride glycerol paste after adjustment and grinding. If the X-ray shows that the pulp horn protrudes into the apex, direct pulp capping should be performed as soon as possible.

3. When the roots of young permanent teeth are not fully developed and are complicated by pulp disease, direct pulp capping or pulpotomy should be performed; if complicated by apical periodontitis, apexification should be performed.

4. For adults with pulp and periapical diseases, root canal treatment should be performed. If the root is less than 1/2 formed and periodontal disease occurs, the tooth should be extracted.