Understanding Human Dentition and Development

May 11, 2025

Lecture Notes: Human Dentition

Introduction to Human Dentition

  • Definition: Study of teeth pattern and functions in humans.
  • Involves:
    • Arrangement of teeth
    • Characteristic features (size, shape)
    • Total number of teeth

Teeth in Humans

  • Humans typically have 32 teeth.
  • Humans are described as 'diphyodont.'

Diphyodont Explanation

  • Diphyodont: Having two sets of teeth.
    • Not referring to both upper and lower jaw.
    • Two sets:
      • Deciduous Teeth: Also known as baby teeth, milk teeth, primary teeth.
      • Permanent Teeth: Follow after deciduous teeth fall out.

Development of Teeth

  • Deciduous teeth:
    • Appear a few months post-birth
    • Total: 20 teeth
    • Growth complete by age 2-3.
  • Permanent teeth:
    • Begin to develop at age 5.
    • Total: 32 teeth.

Dentition Patterns

  • Fixed number and arrangement of teeth.
  • Dental Formulae: Used to understand dentition patterns.

Human Dental Formula

  • For an adult human, the dental formula is:
    • 2 1 2 3 / 2 1 2 3
  • Upper Jaw: 16 teeth total
    • 2 incisors, 1 canine, 2 premolars, 3 molars on each side
  • Lower Jaw: 16 teeth total
    • Similar pattern as upper jaw
  • Total Teeth: 32 (16 upper + 16 lower)

Infant Dental Formula

  • Infants have 20 milk teeth.
  • The lecture poses a question on the dental formula for infants.

Conclusion

  • Understanding human dentition involves knowing the arrangement, characteristics, and formulae governing teeth development and presence in humans. The concept of diphyodont plays a crucial role in distinguishing between the two sets of teeth in a human lifecycle.