Lecture Notes: Development of Orofacial Structures and Cleft Formation

Key Concepts

• Embryonic Development of the Face

  • The development of the human face involves tissues wrapping around and meeting at various points.
  • Failure in this fusion process can lead to orofacial clefts such as cleft lip or cleft palate.

• Orofacial Clefts

  • Occurs when tissues in the facial region fail to fuse properly.
  • Can occur in regions such as the upper lip and the palate (soft and hard palate).
  • Potential impacts: Breathing, eating, and speech difficulties.

Anatomy Related to Cleft Formation

• Midsagittal Section of the Human Head

  • Structures visible: frontal bone, nasal septum, palate, upper/lower lip, mandible, and tongue.
  • Teeth normally project from the mandible and maxillary bone.

• Developmental Structures

  • Germ Layers: Three sheets of tissue that form the human body.
  • Around week 4, these tissues fold into an embryo-like structure.

• Prominent Structures in Facial Development

  • Fronto Nasal Prominence: Forms the central core of the face, including the forehead, nasal cavity, nasal septum, upper lip, and primary palate.
  • Philtrum: Indentation between the nose and upper lip, vestigial in humans but functional in other mammals.
  • Fingal Apparatus: Develops the tongue, mandible, lower lip, lateral aspects of the upper lip, and secondary palate.

Cleft Formation Types

• Cleft Lip

  • Unilateral cleft: Failure on one side.
  • Bilateral cleft: Failure on both sides.
  • May extend from the lip to the palate.

• Cleft Palate

  • Can affect the primary or secondary palate or both.
  • May result in a gap between the nasal cavity and oral cavity, leading to potential feeding and breathing issues.

Implications of Orofacial Clefts

• Health Issues

  • Feeding difficulties, especially in infants.
  • Increased risk of ear infections due to improper nasopharynx closure.
  • Potential for life-threatening complications if untreated.

• Surgical Treatments

  • Surgical repair is typically done in stages.
    • Cleft palate: Repaired between 6-12 months.
    • Cleft lip: Repaired around 3 months.

Orofacial Cleft Statistics

• Occurrence: About 1 in every 700 births worldwide.
• Costs: Around $100,000 in lifetime treatment costs in the U.S., including medical and therapeutic services.
• Effects vary among different populations, commonly seen in Asian and Native American groups.

Additional Resources

• Brilliant.org
  • An online learning platform focused on STEM subjects.
  • Offers interactive lessons in math, science, and computer science.
  • Current promotions available for free trials and discounts.

Note: These notes are structured to provide a high-level overview of the lecture content on orofacial development and cleft issues, ensuring a comprehensive understanding of the material presented.