From the time we were little, we were told to brush our teeth after meals, or at least twice a day. We were reminded to eat our fruits and vegetables, and some of us even learned how to floss. Careful parents began their kids’ dental routines before their babies had teeth – wiping their gums with gauze and cleaning their itty bitty teeth. And yet the cavities keep coming. For a long time, it was believed that cavities came from poor dental care, but even people who brush and floss religiously end up with rotting teeth.
Dental caries is the technical name for cavities, and is expressed by painful ‘holes’ in your enamel, dentin, and deeper into your teeth. The holes expose your nerves and blood vessels, causing irritation, pain, and infection. At the early stages, a filling or crown can be used to seal the hole and cover exposed nerves. If it goes too long untreated, you might need a root canal to dig into the fleshy parts and extract all infected tissues. The infected tooth might have to be pulled out altogether.
Dr. Lin’s theory
Unfortunately, dental caries is infectious, so the rot can spread to other teeth, and the pathogens can seep into your blood and infect other organs. That’s how a simple unattended cavity can lead to admission in overnight wards. And yet cavities are fully preventable. Top Aussie dentist Dr. Steven Lin has offered an alternative theory that is becoming increasingly popular. (His book and TV appearances help).
Dr. Lin believes all dental problems stem down to one thing – diet. He believes watching what you eat can prevent everything from wisdom tooth impaction to braces. In his reasoning, the spacing issues that prompt braces and extractions come from shifting jaw size. Anyone who’s studied evolution knows our ancestors had much larger jaws than we do. And even before we started shrinking our jaws for aesthetic reasons, nature was responding to our dumbed down diets. We eat soft, processed foods right from childhood, so our jaw muscles don’t exercise as much, develop as fully, or grow as wide.
Then when our 32 teeth try to force their way into mouths too small for them, we get crooked smiles and oddly-angled molars. Eat right from infancy and your teeth (and jaw) will grow just fine. Dr. Lin says our plates require Vitamin A, D, K, calcium, and collagenous foods. Meat on bone, carrots, celery, and fresh crunchy foods exercise our jaws in the same way that barbells exercise our triceps. So the bones and muscles grow stronger and broader, creating adequate space for straight teeth and a pretty smile.
Bacteria is good
His theories extend into dental caries as well, using a completely counter-intuitive line of thinking. In the same way we use calibrated bacteria to preserve milk, make cheese, cure infections, and create vaccines, Dr. Lin believes mouth bacteria are a blessing. Their function is to destroy harmful germs and keep our mouths healthy and pristine. The problem begins when there’s too much of it, because the bacteria operate by consuming leftover bits of food in our mouths, the bits that aren’t swallowed or brushed away.
If these food bits are left to rot, they can cause problems. In the past we believed that decomposing food is what caused cavities, but it turns out it’s the bacteria that wear away our tooth surfaces. In the right amounts, bacteria eat leftover food and excrete acid. The saliva in your mouth then neutralises the acid and washes away any food particles the bacteria didn’t get to. When you eat excess sugar and processed foods two things happen.
One, the bacteria over-eat, producing more acid than your saliva can wash away. This acid then eats away at your enamel, causing cavities. Two, because you’re constantly snacking, your mouth doesn’t rest, and your saliva doesn’t have enough time to clean your mouth. Ergo, more acid, more caries. So the solution isn’t just to brush and floss, you also have to give your mouth ‘breathing room’ and lower your intake of processed sugars.
Bite for better health
At the same time, replace your unhealthy food choices with crunchy, ‘bitey’ foods. They exercise your jaw more, take longer to digest, and push your mouth to produce more saliva. More saliva means more bacterial rinse, which results in less acid. And since the bacteria are getting just enough ‘food’, they excrete less acid and expose your enamel to less damage. Also, digestion begins in the mouth. Saliva breaks down starch and simple sugars, providing nourishment for bacteria. It’s a complex interwoven cycle that can be calibrated by eating less processed sugar, eliminating mid-meal snacks, and giving your jaws more exercise. Also, brush and floss twice a day, and see your dentist twice a year.