Understanding Cementum in Dental Anatomy

Apr 27, 2025

Lecture Notes: Cementum in Dental Anatomy

Overview of Periodontal Structures

  • Periodontal Structures: Structures surrounding the tooth, including:
    • Gums
    • Periodontal ligament fibers
    • Surrounding bone
    • Cementum (focus of this lecture)

Cementum: Definition and Characteristics

  • Cementum: A layer covering the root of the tooth
    • Yellowish-brown color
    • Mineralized tissue (contains minerals)
    • Covers only the root, not the enamel

Function and Importance of Cementum

  • Seals Dentinal Tubules:
    • Dentinal tubules cause sensitivity if open
    • Cementum covers and seals these tubules, reducing sensitivity
  • Preservation of Cementum:
    • Important not to remove cementum during dental procedures
    • Protects from sensitivity by preserving tubule sealing

Types of Cementum

  • Acellular Cementum:
    • Thinner layer
    • Contains no living cells
    • Non-regenerative: Once removed, cannot be replaced
    • Located towards the enamel
  • Cellular Cementum:
    • Thicker layer
    • Contains living cells known as cementocytes
    • Regenerative: Builds up over time due to stress (grinding, clenching)
    • Located towards the apex and intra-radicular parts of the root
    • More cementum builds up with age due to attrition compensation

Summary of Cementum Location and Function

  • Acellular Cementum:
    • Located at the top near enamel
    • Not replaceable once lost
  • Cellular Cementum:
    • Located at the root's apex
    • Builds over time to cushion root due to tooth attrition

Conclusion

  • Cementum plays a crucial role in dental health by protecting dentin and reducing sensitivity.
  • Understanding the difference between acellular and cellular cementum is important for preserving dental health, especially during cleaning and debridement procedures.