Cephalometric profile analysis between genders. A study protocol

Background: According to current American Association of Orthodontists guidelines, two-dimensional lateral and posteroanterior cephalometric radiographs are recognized as essential components of diagnostic imaging records in orthodontics. Cephalometry is defined as the discipline that analyzes the craniofacial complex in a segmented way, to study the interrelationships between its structures and understand how the growth or alteration of one of these structures can compromise the whole. Through cephalometry, it is possible to indicate the clinical approach for patients, involving dental therapy with intraoral appliances and physical therapy with continuous positive pressure in the upper airway. Objectives: Investigate possible differences in cephalometric anatomical patterns between genders. Methods: This study protocol follows the STROBE - Strengthening the Reporting of Observational Studies in Epidemiology guidelines. A convenience sample will be used, consisting of teleradiography (cephalograms) of adult patients of both genders, carried out in a private Dental Clinic, located in the city of São José dos Campos (SP), Brazil, by the established inclusion and exclusion criteria. Six angular and nine linear measurements will be used in the analysis of cephalometric measures according to the study protocol. The exams will be distributed into three groups and paired according to the value of the angle formed between point A nasion and point B nasion (ANB). Groups will be formed by exams with class 1 skeletal relationship (0o < ANB angle ≤ 4º), group 2 with class 2 exams (ANB angle > 4°), and group 3 formed by class 3 exams (ANB angle ≤ 0°). Considerations:  In some cases, craniofacial changes may predict the risk of sleep-disordered breathing, such as obstructive sleep apnea (OSA). Increased length and thickness of the soft palate and hyoid bone in the mandibular plane and retrognathia are associated with the pathogenesis of OSA. Therefore, the etiology of sleep-disordered breathing may vary in patients according to gender, according to cephalometric analysis.