Tag Archives: dentinal tubule



Dentin-forming cells, odontoblasts, which originate from the ectomesenchyme, form a single layer of cells between the dentin and pulp. The cell body is located on the pulpal wall of dentin and the cellular process extends into the dentinal tubule within the mineralized dentin. The cell bodies are from 3 to 5 m wide and 20 to 40 m long depending on the age of the tooth. The odontoblastic process fills the lumen of the dentin tubule and it is composed of a main trunk, with a diameter of 0.5 to 1 m, and lateral branches. Contrary to the cell body, cell organelles (Golgi apparatus, rough endoblastic reticulum or mitochondria) usually do not appear in the odontoblastic process; however, microtubules, filaments and coated vesicles are present. Odontoblasts are connected to each other with interodontoblastic collagen, the so-called von Korff fibers. Frequent bundles of collagen fibrils enter the odontoblast layer from predentin and are present between odontoblast cell bodies. Ultimately they pass through the odontoblast layer into pulp. Histologically, secretory odontoblasts are columnar in shape. A large number of cytoplasmic organelles are identifiable in young odontoblasts, whereas, aged odontoblasts lose their columnar shape and contain a small number of Golgi apparatus and a small-sized rough endoblasmic reticulum. Continue reading