Nitrous oxide exposure in dental personnel during sedation: an underrecognized problem with serious consequences

Relevance. Nitrous oxide-oxygen sedation has been widely used in Russia since the early 2000s. It is widely regarded as an effective method for managing the behavior of uncooperative patients. However, despite generally positive assessments of its safety and efficacy, there remains a lack of research into the potential negative consequences and risks associated with its use, both for patients and healthcare personnel.

Objective. To provide structured information that will help dentists working with nitrous oxide sedation minimize its potential toxicity for all personnel involved.

Materials and methods. Publications from both international and Russian databases over the past 30 years were reviewed for key terms related to the effects of nitrous oxide on dental personnel. The initial selection process involved screening titles and abstracts, followed by a full-text review of the remaining articles. From the 145 sources identified, 33 of the most relevant studies were selected.

Results. Nitrous oxide has been used in dentistry for over 150 years, but its significant toxicity raises concerns about its safety. The primary harmful mechanism is the irreversible oxidation of vitamin B₁₂, which disrupts essential processes such as DNA synthesis, myelin formation, homocysteine metabolism, and folic acid metabolism. High-risk groups include dental personnel (due to chronic exposure), individuals with B₁₂/folate deficiency, those with congenital MTHFR gene mutations, people with chronic diseases (such as autoimmune disorders and diabetes), pregnant women, and others. Acute effects for dental personnel include dizziness, nausea, and impaired cognitive and motor functions. Chronic effects can be neurological (paresthesia, ataxia, demyelination of peripheral nerves), hematological (anemia, leukopenia), cardiovascular (thromboembolism, hypertension), reproductive (reduced fertility, pregnancy complications), and immune-related. Despite control measures such as ventilation, nitrous oxide monitoring, and respirators, the risk remains due to system leaks and insufficient awareness. Regular check-ups for personnel, twice a year, are critical are critical, including tests for homocysteine and methylmalonic acid, complete blood count, and neurological evaluations when symptoms arise. Dentists must be informed about the occupational risks of nitrous oxide.

Conclusion. Proper use of nitrous oxide sedation minimizes these risks. Dentists' proficiency in behavior management techniques, local anesthesia, and personal responsibility for following safety protocols are crucial for ensuring the safety of dental personnel.

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