Cephalometric evaluation of facial pattern and hyoid bone position in children with obstructive sleep apnea syndrome Bruno B. Vieira a, *, Carla E. Itikawa a , Leila A. de Almeida b , Heidi S. Sander b , Regina M.F. Fernandes b , Wilma T. Anselmo-Lima c , Fabiana C.P. Valera c a Division of Orthodontics, Dental School of Ribeira˜o Preto, University of Sa ˜o Paulo, Ribeira˜o Preto, SP, Brazil b Departmento of Neurology, School of Medicine of Ribeira˜o Preto, University of Sa ˜o Paulo, Ribeira˜o Preto, SP, Brazil c Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, School of Medicine of Ribeira˜o Preto, University of Sa˜o Paulo, Ribeira˜o Preto, SP, Brazil 1. Introduction Mouth breathing is one of the most frequent symptoms in childhood, and rhinitis and tonsils hypertrophy are the most frequent causes for it [1]. It influences the perioral muscles and soft tissues, and thus affects the apposition of bone tissue during the infant growth [2]. The severity of respiratory disorders may range from intermittent nasal obstruction to more exuberant symptoms such as obstructive sleep apnea syndrome (OSAS) [3]. It has been previously reported that adult patients with OSAS present a more anterior and inferior hyoid bone position when compared to controls, associated to lower position of the tongue. This is related to changes in geniohyoid muscle, which in turn worsen apnea during sleep [4]. The position of the hyoid bone may be also related to a poorer prognosis in surgeries for uvulopala- topharyngoplasty (UPPP) for OSAS in adults, and patients with a higher distance between the hyoid bone to the mandibular base present a poorer postoperative success [5]. Tonsils hypertrophy is the main cause of OSAS in children [6]. In this age group, OSAS may be more subtle and silent, whereas this characteristic does not prevent the development of serious neurobehavioral and cognitive impairment, as well as facial and occlusal changes. The study of facial development and mainly of the hyoid position in children precisely diagnosed with OSAS has been scarcely reported in the literature. The purpose of this study was to evaluate children in scholar age, comparing children with OSAS (group 1) to nasal breathers (group 2), in terms of skeletal facial and hyoid changes. 2. Materials and methods Twenty patients with OSAS and 20 nasal breathing patients, from 7 to 10 years, and with mixed dentition, were selected. Patients with systemic disorders and those with adjuvant orthodontic, speech therapeutic and otorhinolaryngologic treat- ment were excluded. International Journal of Pediatric Otorhinolaryngology 75 (2011) 383–386 ARTICLE INFO Article history: Received 10 November 2010 Received in revised form 6 December 2010 Accepted 9 December 2010 Available online 8 January 2011 Keywords: OSAS Cephalometry Hyoid bone Mouth breathing Children Growth and development ABSTRACT Objectives: To assess the development of face and hyoid bone in children with obstructive sleep apnea syndrome (OSAS) through lateral cephalometries. Materials and methods: Children aged 7–10 years with mixed dentition and with no previous otorhinolaryngologic, orthodontic or speech therapy treatments were studied. Twenty nasal breathers were compared to 20 mouth breathing children diagnosed as OSAS patients. All children underwent otorhinolaryngologic evaluation and cephalometries; children with OSAS also underwent nocturnal polysomnography in a sleep laboratory. Results: Children with OSAS presented increase in total and lower anterior heights of the face when compared to nasal breathers. In addition, children with OSAS presented a significantly more anterior and inferior position of the hyoid bone than nasal breathers. No significant differences in upper, anterior or posterior heights of the face were observed between groups. Conclusion: The results suggest that there are evident and early changes in facial growth and development among children with OSAS, characterized by increased total and inferior anterior heights of the face, as well as more anterior and inferior position of the hyoid bone. ß 2010 Elsevier Ireland Ltd. All rights reserved. * Corresponding author at: Av. Monte Alegre, 3900–128 andar, Bairro: Monte Alegre, CEP: 14049-900, Ribeira ˜o Preto, Sa ˜o Paulo, Brazil. Tel.: +55 16 36235290; fax: +55 16 36022860. E-mail addresses: facpvalera@fmrp.usp.br, facpvalera@uol.com.br (B.B. Vieira). Contents lists available at ScienceDirect International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl 0165-5876/$ – see front matter ß 2010 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijporl.2010.12.010