A Modified Expandable Headgear-Activator for Combined Adenotonsillar Hypertrophy and Bimaxillary Constriction: Insights from a 9-Year Follow-Up
Year: 2026
Type: article
Study design: Case Report
Abstract: This report describes the successful long-term, non-extraction orthodontic management of an adolescent with high-angle skeletal Class II malocclusion, bimaxillary constriction, lip incompetence, and chronic mouth breathing with adenotonsillar hypertrophy. Treatment initiated at CVMS II employed a patented headgear-activator appliance to achieve concurrent vertical control, mandibular advancement, and arch expansion, followed by fixed therapy. Five-year clinical follow-up with cephalometric evaluation at the end of active treatment confirmed significant skeletal correction, with the ANB angle reducing from 4.4° to 3.0°, while vertical dimensions remained stable (SN-MP: 41.8° to 41.3°; FH-MP: 34.3° to 32.2°). Transverse expansion resolved the posterior crossbite, transforming constricted arches into harmonious ovoid forms. Lip seal and a straight facial profile were achieved without surgical airway intervention. These outcomes suggest that early functional orthopedic treatment emphasizing three-dimensional control prior to fixed therapy can yield stable skeletal, occlusal, and aesthetic results while circumventing extractions. The prolonged soft tissue adaptation observed further underscores the necessity of extended follow-up for accurate assessment of orthopedic stability.
Institution: Zhejiang University
Language: English
Subfield: Orthodontics
Field: Dentistry
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,320
OpenAlex ID: W7163989345