Anatomy of a Tooth
Most people could benefit from learning a little more about dental anatomy. In addition to helping you follow along with the explanations your dentist in Madison gives you during your appointments, understanding more about tooth and jaw structure can help you to recognize the signs of trouble and take corrective steps early. Here is an explanation of basic tooth structure and the individual components that make up a tooth.
Basic Tooth Structure
The crown is the visible portion of the tooth, which is shaped differently depending on the placement of the tooth and its role in your mouth. For example, incisor crowns are long and flat to pierce foods, while molars are wide and rough to tear tough foods like meat and fibrous vegetables.
The root is the portion of the tooth that anchors the tooth in place. Dental roots are embedded into the jawbone, and they are typically much longer than the crown portion—making up about 2/3rds of the overall tooth height. Normally the root isn't visible, but gingivitis and periodontal disease can cause the gum tissue to recess and reveal it. Unfortunately, because enamel only covers the crown portion of the tooth, the root is softer, easier to damage, and more susceptible to decay.
Jawbone and Aveolar Process
Your teeth aren’t anchored directly into your jawbone. Instead, they are situated in sockets that are held in place by a special bone called the aveolar process, which rests within the jawbone. The aveolar bone is compact bone tissue that contains lymphatics, blood vessels, nerves, and fibers. Because it is living tissue, it is subject to damage from bacteria and infections, which can cause the teeth to become loose in their sockets.
Interior Anatomy of a Tooth
Dental enamel is the white, shiny covering of the dental crown. Enamel is made up of hydroxyapatite, a crystalline version of calcium phosphate. Formed underneath the gum tissue when the teeth are developing, enamel is an extremely hard material, ranking a 5 on the Moh’s hardness scale. To put that number in perspective, dental enamel is harder than steel, gold, silver, nickel, iron, and platinum. Unfortunately, even dental enamel is no match for the acidic compounds bacteria generate, and over time, enamel can erode and decay, forming dental cavities.
Dentin is the layer of tooth tissue that lies beneath the enamel. Dentin is softer and more porous than enamel, containing thousands of microscopic tubules. Because these tubules can act as a “freeway” to the sensitive nerves and dental pulp of the tooth, exposed dentin can cause extremely sensitive or painful teeth.
Pulp is the soft, vascular living tissue inside of the tooth. Blood vessels, nerves, and connective tissue line the pulp chamber, rushing nutrients, water, and white blood cells to the teeth to keep them alive and well. Dental fractures caused by impact or tooth grinding can expose the pulp, causing pain, infections, or even tooth death.
Cementum is the hard layer that covers the tooth root, consisting of around 45-50% hydroxyapatite. Harder and lighter-colored than underlying dentin, cementum has the highest fluoride content of all mineralized tissue. Cementum binds the roots of teeth to the gums and jawbone. Oral decay sparked by periodontal disease can affect the strength of cementum, which can cause the teeth to fall out of their sockets.
In addition to cementum, the teeth are also held in place by the periodontal ligament. Periodontitis can inflame this ligament, leading to cell death and loss of tooth stability.
For more information about oral anatomy and how dental decay could affect your teeth, make an appointment with Oak Park Dental today. Dr. Gyurina is always ready to help you improve your dental health!