The use of CBCT in orthodontics with special focus on upper airway analysis in patients with sleep-disordered breathing.

Applications of cone-beam CT (CBCT) in orthodontics have been increasingly discussed and evaluated in science and practice over the last two decades. The present work provides a comprehensive summary of current consolidated practice guidelines, cutting-edge innovative applications, and future outlooks about potential use of CBCT in orthodontics with a special focus on upper airway analysis in patients with sleep-disordered breathing. The present scoping review reveals that clinical applications of CBCT in orthodontics are broadly supported by evidence for the diagnosis of dental anomalies, temporomandibular joint disorders, and craniofacial malformations. On the other hand, CBCT imaging for upper airway analysis-including soft tissue diagnosis and airway morphology-needs further validation in order to provide better understanding regarding which diagnostic questions it can be expected to answer. Internationally recognized guidelines for CBCT use in orthodontics are existent, and similar ones should be developed to provide clear indications about the appropriate use of CBCT for upper airway assessment, including a list of specific clinical questions justifying its prescription.

Are the severity of obstruction and the apnea-hypopnea index related to orofacial anatomy in children with obstructive sleep apnea? a kinetic MRI study.

OBJECTIVES: The proportionality between anatomical characteristics and disease severity in children and adolescents with obstructive sleep apnea (OSA) has not been well characterized. The present study investigated the relationship between the dentoskeletal and oropharyngeal features of young patients with OSA and either the apnea-hypopnea index (AHI) or the amount of upper airway obstruction. METHODS: MRI of 25 patients (8- to 18-year-old) with OSA (mean AHI = 4.3 events/h) was retrospectively analyzed. Sleep kinetic MRI (kMRI) was used to assess airway obstruction, and static MRI (sMRI) was used to assess dentoskeletal, soft tissue, and airway parameters. Factors related to AHI and obstruction severity were identified with multiple linear regression (significance level α = 0.05). RESULTS: As evidenced by kMRI, circumferential obstruction was present in 44% of patients, while laterolateral and anteroposterior was present in 28%; as evidenced by kMRI, obstructions were retropalatal in 64% of cases and retroglossal in 36% (no nasopharyngeal obstructions); kMRI showed a higher prevalence of retroglossal obstructions compared to sMRI(p = 0.037); the main obstruction airway area was not related to AHI; the maxillary skeletal width was related to AHI (ß = -0.512, p = 0.007) and obstruction severity (ß = 0.625, p = 0.002); and the retropalatal width was related to AHI (ß = -0.384, p = 0.024) and obstruction severity (ß = 0.519, p = 0.006). CONCLUSIONS: In children and adolescents, the severity of OSA and obstruction were inversely proportional to the maxillary basal width and retropalatal airway width. Further studies are needed to assess the benefits of targeted clinical treatments widening the transverse dimension of these structures.

Case 280: Trichopoliodystrophy.

HistoryAn 8-month-old previously healthy boy was referred to our institution by the maternal child health center for progressive truncal hypotonia and developmental delay. This infant was born after an uncomplicated pregnancy with no perinatal complications. He was delivered at full term via spontaneous vaginal delivery. Two of his older male siblings died around 2-3 years of age due to pneumonia. According to the parents, these siblings also displayed reduced muscle tone, and one of them developed recurrent seizure.On physical examination, the child showed marked head lag and did not reach out to objects. Visual and auditory development were normal. His head circumference was below the third percentile, and his body weight was at the 10th percentile. His hair was sparse and coarse. A mild pectus excavatum deformity was present. Skull and chest radiographs were obtained (Figs 1, 2), and the patient underwent MRI of the brain (Fig 3).

Case 280.

HistoryAn 8-month-old previously healthy boy was referred to our institution by the maternal child health center for progressive truncal hypotonia and developmental delay. This infant was born after an uncomplicated pregnancy with no perinatal complications. He was delivered at full term via spontaneous vaginal delivery. Two of his older male siblings died around 2-3 years of age due to pneumonia. According to the parents, these siblings also displayed reduced muscle tone, and one of them developed recurrent seizure.