Our teeth have essentially three parts: The outer Enamel, middle Dentin, and inner Pulp.
Enamel: The hardest tissue of the body, even harder than bone, that helps protect the softer inside of the tooth1. This is the first line of defense against acids and bacteria-causing cavities.
- 96% Inorganic Material:
- Calcium Phosphate in Hydroxyapatite crystals–this is present in bone and teeth
- Very small amounts of carbonate, magnesium, potassium, and fluoride
- 3% water
- 1% Organic Material
- Both of these proteins help form the calcium phosphate matrix known as Hydroxyapatite, but very few remain in mature teeth1.
Dentin: The layer directly beneath Enamel. It is still harder than bone, but softer than enamel.
- 70% Inorganic Material:
- Hydroxyapatite– with trace amounts of flouride and carbonate
- 20% Organic Material:
- Mainly Type I Collagen–the most abundant type of collagen in the human body
- Non-collagenous proteins– Phosphoproteins, γ-carboxyglutamate-containing proteins, acidic glycoproteins and plasma proteins
- Lipids– interestingly 1.7% of the dentin organic matrix
Dental Pulp: Not like the pulp found in Orange Juice, this pulp is in the center of the tooth beneath the dentin.
- Cells– The pulp has odontoblasts, a type of cell, which produce the Dentin that surrounds the pulp
- Connective Tissue– Type I and Type III collagen as the predominant protein. Fibronectin used for cell adhesion
- Blood Supply– Oxygen rich arterioles enter through the bottom of the tooth roots and exit back out via venules.
- Nerve Fibers– Also entering at the bottom of the root, or laterally, small nerve fibers send stimuli back to the brain1.
Keep brushing, flossing, and visiting your dentist regularly to help keep the teeth you have Healthy!
Here’s the link to the toothbrush that I like to use to keep my teeth clean: Oral-B 7500 Power Rechargeable Electric Toothbrush with Replacement Brush Heads and Travel Case, White
- Fitzgerald M. (1992). A Colour Atlas and Textbook of Oral Anatomy, Histology and Embryology. Journal of Anatomy, 181(Pt 2)
- Habibah, T. U., Amlani, D. V., & Brizuela, M. (2020). Hydroxyapatite Dental Material. In StatPearls. StatPearls Publishing.
One response to “What is a Tooth?”
What a great article! Very insightful! Had no idea what made up a tooth.