An orthodontic perspective on Larsen syndrome

Area of Science:

• Orthodontics
• Genetics
• Pediatric Dentistry

Background:

• Larsen syndrome (LS) is a rare osteochondrodysplasia characterized by joint dislocations and craniofacial anomalies.
• Typical LS features include hypertelorism, a prominent forehead, depressed nasal bridge, and flattened midface.

Purpose of the Study:

• To investigate the relationship between craniofacial skeletal morphology and craniofacial anomalies in Larsen syndrome.
• To analyze skeletal and occlusal features contributing to the characteristic facial appearance in LS.

Main Methods:

• Case presentation of a 5-year-old Japanese girl diagnosed with Larsen syndrome.
• Orthodontic analysis including cephalometric evaluations (frontal and lateral) and study models.
• Assessment of skeletal and occlusal relationships to identify dysmorphic features.

Main Results:

• Cephalometric analysis revealed hypertelorism, midface hypoplasia, and a retrognathic mandible.
• These skeletal findings contributed to a flattened facial appearance and a prominent forehead.
• Dental arch constriction and posterior crossbite were observed, associated with the underlying skeletal morphology.

Conclusions:

• The craniofacial skeletal morphology is a direct cause of the craniofacial dysmorphism observed in Larsen syndrome.
• Orthodontic and cephalometric analyses are crucial for understanding LS-related facial anomalies.