Relevance. Orthodontic management of children with congenital osseous disorders of the temporomandibular joint (TMJ) spans the entire course of dentofacial growth and accompanies each surgical stage from early childhood through adolescence. Although a wide range of orthodontic appliances is available for this patient group, published data on their use remain limited and inconsistent. Evidence from Russian and international sources suggests that combining functional orthopedic treatment with distraction osteogenesis (DO) yields more durable, clinically stable outcomes. However, the sequence of appliance use and continuity of care remain poorly organized and insufficiently systematized, a gap compounded by the absence of a unified clinical algorithm and formal practice guidelines. Objective. To analyze existing orthodontic management methods for patients with mandibular ramus hypoplasia and/or aplasia across the stages of comprehensive rehabilitation and to synthesize the available evidence.

Materials and methods. The literature review was conducted in accordance with PRISMA guidelines for systematic reviews and meta-analyses. Searches were performed in PubMed, Medline, EMBASE, and eLibrary using the keywords “orthodontic management,” “mandibular ramus hypoplasia and aplasia,” “functional appliance,” and “stages of orthodontic treatment,” combined with the Boolean operator AND, in both English and Russian. Original publications reporting the use of removable orthodontic appliances in patients with congenital osseous TMJ disorders were analyzed. A total of 1,500 records were identified; 22 met the inclusion criteria and were included in the final review. In addition, a retrospective analysis was conducted of orthodontic outcomes in 40 patients treated at the Department of Orthodontics, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, from 2004 to 2024.

Results. Reports in the Russian-language literature describing specific functional orthodontic appliances for children with unilateral mandibular ramus hypoplasia and/or aplasia due to congenital osseous TMJ disorders are scarce. Most published cases involve the Vankevich appliance (maxilla-supported fracture splint) or a removable plate with a lingual pad (pelotte). To date, no standardized protocol for orthodontic management of these patients has been proposed.

Conclusion. In this patient population, criteria for evaluating the quality of orthodontic care across stages of dentofacial development are lacking, and the continuity of multidisciplinary collaboration within comprehensive dental rehabilitation is insufficiently characterized. A clear clinical strategy for orthodontic management has not been defined, and the biomechanical capabilities of orthodontic appliances in influencing both jaws both jaws are not fully delineated. The optimal integration of surgical and orthodontic stages into a unified, evidence-based treatment protocol also remains to be established.

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.

Relevance. Congenital osseous disorders of the temporomandibular joint (TMJ) in children, leading to unilateral hypoplasia and/or aplasia of the mandibular ramus, play a decisive role in the development of skeletal and functional imbalance of the craniofacial complex. Such defects represent a clear indication for surgical intervention. In accordance with established protocols for comprehensive management, the initial stage involves creating a posterior mandibular support, achieved either through distraction osteogenesis (DO) or endoprosthetic replacement of the affected ramus.

Objective. To summarize current knowledge on the classification and pathogenesis of congenital osseous TMJ disorders and to evaluate the outcomes of existing surgical treatment methods in children and adolescents with this condition.

Materials and methods. The literature review was conducted in accordance with PRISMA guidelines for systematic reviews and meta-analyses. Searches were performed in PubMed, Medline, EMBASE, and eLibrary using the keywords “congenital osseous TMJ disorders,” “hemifacial microsomia (HFM),” “surgical treatment in children,” and “distraction osteogenesis (DO),” combined with the Boolean operator AND, in both English and Russian. Original publications proposing classifications of congenital osseous TMJ disorders were also reviewed. Of the 2000 scientific publications identified, 30 met the inclusion criteria and were included in the final analysis.

Results. Both published data and our own clinical observations show that surgical reconstruction of the mandibular ramus in children, while restoring its anatomical structure, does not establish long-term skeletal and functional balance of the dentofacial system due to ongoing growth and development. Consequently, multiple staged surgical procedures are required to maintain craniofacial stability. Yet, the cumulative effect of repeated operations includes progressive scar formation in the soft tissues and worsening mandibular deficiency, which together reduce the adaptive and compensatory capacity of the dentofacial system.

Conclusion. A critical evaluation of surgical outcomes and of the current state of comprehensive management for children with unilateral mandibular ramus hypoplasia or aplasia in congenital osseous TMJ disorders is essential for advancing research and expanding the potential of multidisciplinary rehabilitation for this patient population.