A couple of years ago, my wife and I were on a walk near our community’s park. A baseball game was taking place on the baseball field and we stopped to watch. I noticed that some of the players were constantly spitting into the dirt near the dugout.
It took almost all of the self-control that I had to stop myself from yelling, “What’s wrong with you!? Don’t you know what great things that spit could do for your teeth? Why would you waste it like that?”
Okay, I might not have actually thought that, but the fact remains that saliva doesplay many important roles when it comes to keeping your teeth in optimal condition.
Luckily, the average person produces about one liter of saliva each day, so there’s still enough to spit out during a baseball game.
Six Ways Saliva Protects Your Teeth
1 -Saliva neutralizes acids that can erode your teeth. Plaque produces acid that causes cavities. Acids can also be found in many of the foods we eat and lots of different beverages that we drink. Another way that we can get acid in our mouth is through acid-reflux from the stomach or by vomiting. Luckily, saliva has molecules called buffers that can neutralize the acid, reducing its effect on our teeth.
2 – Saliva inhibits demineralization of the tooth surface and promotes remineralization. That means that when acids try to dissolve the outer layer of your teeth (the enamel), your saliva is right there, super-saturated with extra calcium and phosphate to prevent the acid from demineralizing your teeth. When the acid is so strong that it does demineralize the tooth, your saliva will neutralize the acid as soon as possible, and then replace the lost tooth with calcium and phosphate.
Saliva can even contain fluoride when people drink fluoridated water or use a fluoride mouthrinse and/or fluoride toothpaste. This extra fluoride in the saliva can help remineralize teeth with the fluoride ions and make them more resistant to future attacks from plaque.
For more information on how fluoride can protect the teeth, read the article The Three Ways that Fluoride Protects Your Teeth.
3 – Saliva cleanses the mouth. After you eat a satisfying meal, your saliva goes to work to rinse away any extra food that may be stuck on your teeth. When the food sticks to your teeth, it can feed the bacteria that live on your teeth, helping them to hurt your teeth. By washing away the food, your saliva is getting rid of the food source for the bacteria, ensuring that your teeth remain in good condition for a long, long time. Saliva can even wash away actual bacteria, preventing them from grabbing onto your teeth and residing there until the time when a toothbrush scrapes it away.
4 – Saliva can kill bacteria. Saliva has many different antibacterial agents in it that can destroy bacteria. This is helpful not only for your teeth, but for your whole body. Specific components in saliva have been shown to slow the growth of a cavity-causing strain of bacteria known as streptococcus mutans. Here’s one study that demonstrated saliva’s antibacterial effect that was published in the Journal of Dental Research.
5 – Saliva strengthens newly-erupted teeth. When teeth first come into the mouth, their enamel isn’t fully developed. Saliva fills in the weak parts of the new tooth with calcium, phosphate, and fluoride to make these new teeth strong and ready for battle against your teeth’s worst enemies.
6 – Saliva can form a protective coating on teeth. Proteins in the saliva bind to the tooth surface. The book Essentials of Dental Caries by Kidd, “Salivary proteins could increase the thickness of the acquired pellicle and so help to retard the movement of calcium and phosphate ions out of enamel.”
By keeping calcium and phosphate in the tooth, the salivary pellicle could aid in preventing cavities. Ironically, the salivary pellicle is a sticky coating that helps cavity-causing bacteria adhere to the tooth surface. In a way, it can be both a good and bad thing.
Further Reading & Conclusion
There are a couple of good reports about saliva, such as Saliva — The Defender of the Oral Cavity by Amerongen and another study by Amerongen about salivary proteins. You’ll probably need a subscription from a major university to get to them, but I thought I would link to them anyway for those of you who are able to access them.
Do you have any questions or comments about how saliva protects your teeth? Leave them below in the comments section!