Associations Apnoea Hypopnoea Index (AHI) and Malocclusions in Growing Patients With Maxillary Constriction: a Prospective Clinical Study.

This observational study aims to evaluate possible associations between data obtained from cardiorespiratory monitoring, clinical examination, and cephalometric analysis in patients with maxillary constriction. First, patients aged 6 to 12 years who present to the Unit of Orthodontics and Pediatric Dentistry, Section of Dentistry, Department of Clinical, Surgical, Diagnostic, and Pediatric Sciences of the University of Pavia will undergo a clinical examination to assess the presence of malocclusions. If malocclusions are identified, the necessary records for the patient's diagnostic-therapeutic assessment will be collected. During the initial visit, parents will also be asked to complete the PSQ-SRBD questionnaire (1) (Appendix A), which serves as a screening test for OSAS. Subsequently, the transpalatal width will be measured on plaster or digital models by evaluating the intermolar distance. According to McNamara, this value in mixed dentition without crowding or spacing ranges between 34 and 36 mm (2), while it is less than 31 mm in cases of crowding, indicating the need for orthopedic or surgical expansion (3). In this study, a cut-off value of 31 mm was used to select the sample with maxillary constriction. If such a malocclusion is present, the operators will verify whether the patient meets the study's inclusion criteria. Cephalometric analysis will be performed on lateral cranial radiographs, focusing on craniofacial characteristics and upper airway measurements, as detailed later in the protocol. The selected children will then be referred to the Sleep Medicine Center at the Mondino Foundation for cardiorespiratory monitoring (AHI). Data from the polygraphic examination, cephalometric analysis, and clinical evaluation will be compared using statistical analysis. If the patient is diagnosed with OSAS (AHI >1) and requires palatal expansion, cardiorespiratory monitoring, clinical evaluation, and cephalometric analysis will be repeated after treatment with an expander and compared with the initial data.