Enamel & Cementum Flashcards
What cells are present in enamel?
Completely acellular.
No blood vessels or nerves.
What cells are present in cementum?
Cellular - cementoblasts
Acellular - no cells
Both have no blood vessels or nerves
What is acellular cementum?
Cementum with no cells. Usually found at the cervical 2/3rds of root, adjacent to dentine. It is the first type formed (primary) and has a better regeneration capacity. Contains Sharpey’s fibres - penetrate deep into the cementum at right angles.
What is cellular cementum?
Contains cementocytes. It is formed later but faster than acellular (secondary) and is usually found in the apical 1/3rd part of the root and in furcation regions. It contains intrinsic collagen fibres parallel to the surface - NO sharpey’s fibres. It plays no role in tooth attachment and is more irregular than acellular.
What are the components of enamel?
Hydroxyapatite - 95% weight, 90% vol
Water - 4% weight, 5-10% vol
Organic matrix - 1% weight, 1-2% vol
What is in the organic matrix of enamel?
Proteins, Ca binding proteins (amelogenins, enamelins), peptides, amino acids
