In the history of dentistry, Formaldehyde (often in the form of Formocresol) was once considered the “gold standard” in root canal treatment, especially for primary teeth, due to its strong bactericidal and tissue fixation capabilities. However, with the advancement of modern medicine and clear evidence of toxicity, the use of this active ingredient is being completely eliminated.

1. Overview of Formaldehyde

Formaldehyde (HCHO) is a simple organic compound but has very strong chemical activity. In solution form, it is known as formalin, commonly used in preserving anatomical specimens and sterilization.

In dentistry, Formaldehyde is the main component of Formocresol (Buckley’s formula includes 19% formaldehyde, 35% cresol, and excipients). It is used to devitalize the dental pulp, disinfect the root canal, and fix remaining pulp tissue.

2. Toxicity and Mechanism of Harm

Although highly effective in disinfection, Formaldehyde is a double-edged sword with serious health risks warned by the International Agency for Research on Cancer (IARC):

• Group 1 Carcinogen: IARC classifies Formaldehyde as a definite human carcinogen. Long-term exposure is closely linked to nasopharyngeal cancer and leukemia.
• Cytotoxicity: Formaldehyde not only kills bacteria but also destroys healthy body cells. It inhibits DNA, RNA, and protein synthesis, causing direct tissue necrosis upon contact.
• Immune and Allergic Reactions: It is a potent allergen (hapten). Repeated contact can cause contact dermatitis, respiratory mucosal irritation, and systemic hypersensitivity.

3. Why is Formaldehyde eliminated in modern dentistry?

Based on clinical studies and recommendations from prestigious medical organizations (such as the International Association of Paediatric Dentistry – IAPD, European Society of Endodontology – ESE), the use of Formaldehyde in modern dental treatment (such as pulpotomy in primary teeth, devitalization of permanent teeth) is opposed for the following reasons:

• Systemic Distribution: Studies using radioactive isotopes show that after placing Formocresol in the pulp chamber, Formaldehyde can permeate through the apex, enter the circulatory system, and accumulate in internal organs such as the liver, kidneys, lungs, and brain within just a few hours.
• Harm to Permanent Tooth Germs: For primary tooth treatment, the drug can seep down to the apical region and cause enamel hypoplasia or developmental complications for the permanent tooth germs underneath.
• Hindering Healing Process: Instead of helping tissue recover, Formaldehyde “mummifies” the pulp tissue, creating a dead tissue zone with no resistance, easily leading to chronic periapical inflammation later.

4. Documents and Warnings from the Ministry of Health of Vietnam

• Toxicity Warning (Ministry of Health Portal): According to official information from the Health Environment Management Agency (Ministry of Health), Formaldehyde is classified as a dangerous toxic chemical. Long-term exposure can cause respiratory damage, allergic dermatitis, and especially increases the risk of leukemia and nasopharyngeal cancer.
• Infection Control Regulations (Decision 3671/QD-BYT): In regulations on disinfection and sterilization of medical instruments, the Ministry of Health always requires strict control of concentration and residues of Aldehyde group chemicals (such as Formaldehyde/Glutaraldehyde) to ensure safety for both medical staff and patients, due to high risks of irritation and cytotoxicity.
• Odonto-Stomatology Treatment Guidelines (Decision 3108/QD-BYT): In current professional guidance documents, the trend of root canal treatment (especially in children) has shifted to conservation and regeneration methods using bioactive materials, instead of the “pulp devitalization” method using toxic chemicals like Formocresol as before.

5. Safe and Biological Alternatives

Modern dentistry has shifted from the perspective of “destruction and fixation” to “conservation and regeneration”. New biomaterials have emerged to completely replace Formaldehyde:

• MTA (Mineral Trioxide Aggregate): Material with high biocompatibility, good antibacterial ability, and stimulates dentin bridge formation to protect the pulp.
• Calcium Hydroxide (Ca(OH)2): Safe disinfection, stimulates healing.
• Bio-materials (Biodentine, Bio-ceramic): Friendly to body tissue, non-toxic, and stimulates tissue regeneration.

Conclusion

The presence of Formaldehyde in dental products today is considered outdated and poses potential legal and health risks. Eliminating this active ingredient not only complies with international safety regulations but also demonstrates professional ethics, aiming for the highest goal of protecting comprehensive health for patients.

Center for Support and Continuing Education