Case presentation
An 8-year-9-month-old male patient of normal intelligence with SJS was
referred to the Department of Orthodontics, Faculty of Dentistry,
Mahidol University, Thailand. He is the only child of a healthy
nonconsanguineous Thai couple. His birthweight was 3.070 kg with
unremarkable prenatal history. Generalized muscle stiffness and abnormal
gait have been observed since his first year. The diagnosis based on
SJS’s cardinal signs, was made at 3 years of age. His medical history
includes hypothyroidism, repeated hospitalization due to severe allergy
and respiratory distress, and severe OSA. He regularly receives
carbamazepine to relieve his muscle contraction, and levothyroxine for
hypothyroidism. Parents noticed occasional snoring at 6 months old and
became worsened with increasing age. Other nocturnal symptoms included
enuresis, choking, and gasping for air. Daytime symptoms include
frequent morning drowsiness and headache, nausea, hypersomnolence, as
well as poor concentration. He was referred to a sleep physician for a
diagnostic polysomnography at the age of seven. The diagnosis for severe
OSA was confirmed with an apnea-hypopnea index of 29 events/hour. The
continuous positive airway pressure (CPAP) was prescribed instead of
adenotonsillectomy to avoid a potential risk of malignant hyperthermia
during a general anesthesia.
On physical examination, the patient had a proportionate short stature
with his weight in the tenth percentile. He presented with multiple
skeletal deformities, and generalized muscle stiffness. Extra-oral
examination revealed a distinctive mask-like facie, blepharophimosis,
low-set ears, microstomia and pursed lip, limited mouth opening (25 mm),
asymmetrical oval facial form, convex facial profile and bimaxillary
retrognathia (Fig. 1). On oral examination, the patient was in mixed
dentition with very severe dental crowding especially in the upper arch.
The amount of dental crowding was measured at 12 and 6 mm for the upper
and lower arch respectively. There was untreated active caries noted.
The maxillary arch was severely constricted with a very high-vaulted
palate. The upper intermolar width was significantly reduced with a
measurement of 36 mm. Bilateral posterior crossbite was observed (Fig.
1). Dental development was within normal range. Permanent mandibular
lateral incisors were clinically missing. Enlarged palatine tonsils were
present in the retropharyngeal area. Radiographic examination confirmed
congenital hypodontia of the lower laterals and supernumerary mandibular
teeth at the premolar region bilaterally (Fig. 2). Cephalometric
analysis demonstrated that the patient had Type I skeleton relationship
with retrognathic maxilla and mandible. The mandible rotated posteriorly
while the maxilla exhibited counter-clockwise rotation. This creates a
hyperdivergent pattern of the jaw bones. Both upper and lower incisors
are retroclined and retruded. Soft tissue measurements showed the upper
and lower lip were in a retrusive position following the underlying
skeletons. The detailed cephalometric characteristics of the patient is
presented in Table 1.