A palate expander, or maxillary expander, is an orthopedic device used to widen the upper jaw (maxilla). This device corrects issues like posterior crossbite and dental crowding when the maxilla is too narrow to accommodate the teeth or support optimal breathing. It works by applying gentle, continuous pressure to the upper jaw structure. Since the upper jaw and the nasal complex are intimately connected, changes in the maxilla often result in changes in the nose.
The Mechanism of Palatal Expansion
Maxillary expansion relies on manipulating the midpalatal suture, a fibrous joint connecting the two halves of the maxilla down the center of the hard palate. In growing patients, this suture is not fully fused, allowing separation under controlled force. Devices like the Rapid Palatal Expander (RPE) or the Miniscrew-Assisted Rapid Palatal Expander (MARPE) use a central screw mechanism to apply lateral pressure. Turning the screw once or twice daily generates force to separate the maxilla halves, increasing the width of the upper dental arch. While effective in children and adolescents, expansion is more challenging in adults due to increased ossification, often requiring surgical assistance.
The Anatomical Link Between the Palate and Nose
The connection between palatal expansion and the nose stems from the shared skeletal architecture of the midface. The bony palate, or roof of the mouth, is also the floor of the nasal cavity. This structure is formed primarily by the palatine processes of the maxilla and the palatine bones. Therefore, widening the palate means widening the base of the nasal cavity. When the expander separates the midpalatal suture, the maxilla halves move laterally, causing corresponding movement in the floor of the nose. This outward movement directly affects the width of the nasal cavity and influences surrounding structures, including the lateral nasal walls and the pyriform aperture. This structural connection ensures that changing the width of the maxilla translates into changing the internal dimensions of the nasal airway.
Clinical Reality of Nasal Changes
Clinical studies have consistently demonstrated that palatal expansion produces measurable changes in the internal nasal structure, which translates into improved function. The expansion causes an increase in the width of the nasal cavity, specifically the nasal floor and the lateral nasal walls, often ranging from 1 to 3 millimeters. This skeletal change results in a measurable increase in the overall volume of the nasal airway, which can be 8 to 25% larger immediately following treatment. The most significant outcome is a reduction in nasal airflow resistance, leading to improved nasal breathing. This functional improvement is a primary benefit for patients with a narrow maxilla who experience chronic mouth breathing or other naso-respiratory problems. The expansion effectively widens the lower portion of the nasal passages, optimizing the path for airflow.
External or cosmetic changes to the nose are typically much more subtle and less predictable than the internal functional changes. Immediately following expansion, some patients may observe a slight increase in the width of the alar base (the width across the nostrils). This change is generally minor, often measuring around 1.6 millimeters, and is usually a transient effect. Studies tracking these changes long-term often find that the immediate widening of the soft tissues regresses or blends with normal growth patterns over time. The elasticity of the soft tissues and the continuous growth of the nose in younger patients tend to minimize any noticeable long-term cosmetic alterations.
Other Effects of Maxillary Expansion
Palatal expansion is a foundational orthodontic procedure with several therapeutic goals beyond affecting the nasal structure. The most common indication is correcting a posterior crossbite, ensuring proper alignment of the upper and lower teeth. The procedure also creates necessary space within the dental arch, which alleviates dental crowding. Increasing the transverse dimension of the maxilla contributes to a broader, more aesthetically pleasing smile. Furthermore, improving nasal breathing positively influences tongue posture and overall craniofacial development.