At an auction in England in 2011, one of John Lennon’s teeth sold for just over US$31,000.
How much are your teeth worth?
Teeth are amazing little miracles. They light up our smiles, we use them to speak and we chew with them more than 600 times at every meal.
Yet, in a society where 1 out of 5 Americans ages 75 and up live without their teeth, many people may not realize that teeth are designed to stay with us for a lifetime.
I’m a dentist and an assistant professor
spanning clinical dentistry and craniofacial regeneration
research. Researchers like me are still deepening our understanding of tooth development, with the ultimate goal of
serving patients with on-demand regrown ones.
In the process, I have developed reverence for natural teeth and for the complex beauty of these biological and
mechanical masterpieces.
Designed for lifelong function
The secret of teeth longevity lies in their durability as well as in how they are anchored to the jaw – picture a
hammer and its hand grip. For each tooth, durability and anchorage are functions of the complex interface between
six different tissues; each alone is a biological marvel.
For anchorage, the cementum, ligament and bone grip the tooth at its root portion that is buried under the gum. The ligament, a soft tissue that is about 0.2 millimeters wide (about the diameter of four hairs), attaches the cementum of the root on one end to the bone of the jaw on the other end. It serves to anchor the tooth as well as to cushion its movement during chewing.
For durability, however, the secret lies in the enamel, dentin and pulp – our focus in this discussion.
Like hair or fingernails, the non-innervated enamel is not sensitive. The decay advances through the 2.5-millimeter thick (tenth of an inch) layer of enamel painlessly. When caught at that phase during a dental checkup visit, the dentist can treat the decay with a relatively conservative filling that hardly compromises the tooth’s structural integrity.
Because of its high mineral content, enamel is stiff. Its lifelong support is provided by the more resilient infrastructure – the dentin.
Dentin and pulp – body and heart
With less mineral content than enamel, dentin is the resilient body of the tooth. It is a living tissue formed of parallel tiny tubes housing fluid and cellular extensions. Both originate from the pulp.
The pulp is the tooth’s soft tissue core. Vastly rich in cells, blood vessels and nerves, it is the life source of the tooth – its heart – and the key to its longevity.
Like smoke detectors communicating with a remote fire station, the cellular extensions within the dentin sense decay as soon as it breaks through the nonsensitive layer of enamel into dentin. Once the extensions communicate the danger signal to the pulp, our tooth sensitivity alarm goes off: The tooth heart is in flames.
The inflamed pulp initiates two protective actions. The first is to secrete an additional layer of dentin to delay the approaching attack. The second is toothache, a call to visit the dentist.
