Pulp devitalization

Devitalization is a dental procedure that involves partial or complete removal of the tooth pulp, followed by root canal treatment.

This procedure is carried out either mechanically or after the use of chemical dental preparations. The second method is considered the most acceptable and common.

Mechanical devitalization performed by the dentist manually, using manual and mechanical tools. In this case, the patient is anesthetized, and a hole is drilled in the tooth pulp to remove the necrotic or inflamed part.

Chemical devitalization is made using a special paste. In this case, the pulp of the tooth dissolves under the influence of the medicine.

There are two variants of devitalizing paste – arsenic-free (paraformaldehyde) paste and arsenic paste.

Arsenic paste – composition and contraindications

Arsenic devitalizing paste consists of the following components:

Arsenic anhydride.
Elements that have an antiseptic and disinfecting effect on the pulp.
Analgesic components.
Components that ensure a long-lasting effect of the paste.
Additional components.

Arsenic in any form is one of the most potent poisons. The toxic dose for humans is 5 mg, and therefore the maximum permissible dose for devitalization is 3 mg.

If the dose is exceeded, such symptoms of intoxication as vomiting and loose stools may be observed.

When arsenic paste is applied to the pulp, gradual death of nerve endings and blood vessels occurs. As the blood supply is cut off, the pulp dies and the transmission of nerve impulses stops.

Many dentists prefer not to use arsenic paste for devitalization, especially when treating children, pregnant women, and nursing mothers. Especially since there are safer and less toxic analogues.

Side effects that may appear after using arsenic paste:

If the dosage is exceeded, signs of intoxication of the body may appear – nausea, vomiting, diarrhea.
If the paste is applied poorly, it may wash out or leak, which is accompanied by a burn of the oral mucosa with further complications.
If the paste is kept in the cavity of the tooth longer than it was intended, the dentin can change color – turn black.
Due to the high toxicity of the paste, periodontitis may begin.
Swelling of the pulp due to inflammation.
The effect of the poison can spread to bone and periosteal tissue, causing their destruction.

There are strict contraindications and restrictions for the use of arsenic paste for pulp devitalization:

It is better not to use this remedy for the treatment of pulpitis in children. Children often remove the temporary filling on their own, and arsenic paste is found in the oral cavity. It is not known what the consequences will be from such an effect of the poison on the child’s body.
Do not use if the patient is allergic to arsenic.
When the roots of the tooth have not finished the formation process.
If the tooth canal cannot be completely cleaned
If a perforation of the tooth root has occurred.
If the patient is at risk of developing glaucoma.
Pregnancy and lactation.

There is a more modern and safer method of chemical devitalization – paraformaldehyde paste. Its use for the treatment of pulpitis in children is a priority.

Paraformaldehyde paste – mechanism of action, advantages of use

Paraformaldehyde paste is applied to the tooth for a longer period than arsenic paste. Instead of wearing arsenic paste for a maximum of 48 hours, the patient should spend 10-14 days with paraformaldehyde. However, this method of devitalization is considered more gentle on the body, since this paste is less toxic. It does not have such an aggressive effect on periodontal tissues as does arsenic. This paste contributes to the death of pulp vessels and the cessation of its blood supply, but does not cause pathological changes in the periodontium even with long-term use.

Paraformaldehyde also has a mummifying effect on the dying pulp. It “extracts” moisture from the pulp, as a result, it dries out.

If you need to devitalize the pulp of a tooth with unformed roots, use only paraformaldehyde paste.