[23] Cleft - Embryology

• Cleft

  • opening to an anatomical part that is not usually open
  • developmental failure leading to non-fusion of musculoskeletal structures in lip and palate
• 3rd - 4th week

  • undifferentiated structures
  • Neuropore and primitive brain
  • stomodeum will become oral and nasal cavity
• 26 days

  • optic pit: eyes
  • hyoid bone
• 28 days

  • 1,2,3,4 (2nd pharyngeal groove)
  • Stomodeum hole will become part of the oral cavity
  • Maxilla and mandibular starts to fuse together
• 5th week

  • face become apparent
  • nasal pits
  • eyes: upright & bilateral
  • optic furrow
  • maxillary process: nasomedial process
  • cardiac prominence
• 5th week branchial arch

  • 1st arch: mandible, 2/3 of the tongue
  • 2nd arch: mid / lower face
  • 3rd arch: Base of the tongue
• 5th week process

  • nasolateral: alaes of nose
  • globular: prolabium and premaxilla
  • maxillary: + globluar, palatal plates (upper lips, alveolar ridge, maxilla)
• 7th week

  • ears will come from bottom
  • nose, eyes, ears will be more recognizable
  • hypertelorism: wide eyes
• 8th week

  • 2 shelves from inner side of maxillary process to form palatine process
  • palatine process - large tongue - small mandible
  • septum: frontonasal and mesoderm of the maxillary process
• 9th week

  • premaxilla ossifies
  • fusion of palatine process from premaxilla backwards
  • soft palate from lateral process
• more than 9 weeks

  • almost to complete (12 week) orofacial profile