No, we’re not thinking about taking up hair styling here at My Hills Dentist. Instead, we’re calling attention to one of the many genetic factors that can increase your risk for oral health problems. In this case, variations in your genes that cause minor problems with your hair are probably a sign that you’re at a higher risk for cavities.
Why Hair and Teeth Are Linked
Hair and teeth seem to be very different structures, but when it comes to biology things are not always what they seem. Evolution dictates that the body’s current complexity was derived from its former simplicity. Teeth and hair (and fingernails, for that matter) are all derived from scales. In fact, enamel first appeared in the scales on faces of bony fishes and only later migrated into the mouth.
With the simplistic nature of evolution, the same genes are used to code for different structures, influenced by their environment to determine whether they turn into a tooth or a hair, so changes in that gene will lead to changes in both related structures.
How Your Hair Signals Your Cavity Risk
Researchers found that an essential protein in hair, keratin, is also an essential protein in the non-mineral part of tooth enamel, and that it helps build and reinforce the structure. Alterations in a gene that controls keratin development, designated KRT75, changed not just the way hair functions, but also the way tooth enamel develops.
So how does altering KRT75 change your hair? There are many potential effects of identified variations of the KRT75 gene, including a tendency toward ingrown hairs, loose anagen hair syndrome (a condition in which hair comes out easily and doesn’t grow vigorously during childhood), and monilethrix (a condition in which hair appears beaded and breaks easily).
The variation representing loose anagen hair syndrome has been linked to an increased cavity risk in children, but not in adults, likely related to the disorder’s predominance in childhood.
But researchers looked with particular interest at the variation that put people at risk for ingrown hairs. They found that it was related to structural weaknesses in tooth enamel, tiny cracks, enamel defects, and increased colonization of bacteria inside the enamel, all signs of impending tooth decay.
Biology Is Not Destiny
Whenever we talk about this kind of research, it’s important to understand that although your genes do influence your risk of tooth decay, gum disease, tooth loss, and other aspects of your oral health, they are not the sole determiners of your oral health. Oral hygiene, regular visits to your dentist, and your diet remain major factors that have at least as much–if not more–influence on your oral health.