The fifth case describes a twelve-year-old female referred to the dental department internally from the metabolic department. Medically, she had Mucopolysaccharidosis type IVA (Morquio Syndrome (MPS IVA)), severe obstructive sleep apnea requiring nocturnal CPAP, bilateral conductive and sensorineural hearing loss, bilateral corneal clouding, left ventricular hypertrophy, congenital bilateral talipes equinovarus (surgically corrected), genu valgum (surgically corrected), atlanto-axial instability (awaiting surgical stabilisation), and short stature. Her MPS IVA was managed with Vimizim, an enzyme replacement therapy (ERT).\nThe patient was referred to the orthodontic department regarding canine ectopy and supernumerary teeth. A retrognathic mandible and proclined maxillary incisors contributed to an increased overjet of 7 mm. Intraorally microdontia, maxillary anterior spacing, and hypoplastic enamel were evident (Figure ). The soft tissues were healthy, and no caries were present. The maxillary left permanent canine (UL3) was palatally impacted and four supernumerary teeth were present radiographically (Figure ), distal to each third permanent molars (distomolars). The orthodontic treatment plan consisted of a sectional fixed appliance to idealize the space for the impacted canine tooth and a functional appliance to reduce the overjet. Orthodontic tooth movements progressed unremarkably.
The third patient describes a twelve-year-old female who was referred internally from her metabolic consultant concerning an acute apical abscess. Medically, she had mucopolysaccharidosis IIIA (Sanfilippo Syndrome). Medical comorbidities included gastroesophageal reflux, megarectum, chronic constipation, reduced visual acuity, and behavioral and learning difficulties. Medication included lansoprazole, macrogol, and aripiprazole. She was under the care of a metabolic dietician who prescribed frequent fruit smoothies and fruit yoghurt consumption to aid bowel movements.\nComprehensive oral examination was constrained by difficulties in cooperation. Fortuitously, compliance permitted lateral oblique radiography (Figure ) and a diagnosis of acute apical abscess of the left mandibular first permanent molar (LL6) and second primary molar (LLE) and a retained primary first molar (LLD) was confirmed. Due to the extent of the infection, extraction was deemed the treatment of choice. An orthodontic opinion was obtained regarding the horizontal inclination of the left mandibular second premolar (LL5) and the benefits of extracting the maxillary left first permanent molar (UL6) as a compensating extraction. Insufficient cooperation mandated general anesthesia for a detailed examination, fissure sealants of the right maxillary and mandibular first permanent molars (UR6, LR6) and extraction of left maxillary and mandibular first permanent molars (UL6, LL6), left mandibular primary first and second molars (LLE, LLD), and fluoride varnish (22 600 ppm) application.