The concept of “hydrating your teeth” involves maintaining the moisture content within the tooth structure and its surrounding oral environment, rather than soaking the enamel. Teeth are composed of highly mineralized tissues, primarily the outer enamel and the underlying dentine, which contain a small but important amount of water. Enamel is the hardest substance in the human body, yet it is partially porous, holding approximately four percent water by weight. The softer dentine holds a higher moisture level, closer to ten to twenty percent. This internal moisture contributes to the structural integrity and slight translucency of the enamel.
Understanding Tooth Moisture and Saliva’s Function
Saliva is the body’s natural fluid defense system and the primary source of external moisture for the teeth. Composed of approximately 99% water, it acts as a solvent and a transport medium, carrying essential components to the tooth surface. The constant flow of saliva mechanically washes away food debris and harmful bacteria.
A major function of this fluid is remineralization, a process that repairs microscopic damage to the enamel. Saliva is supersaturated with calcium and phosphate ions, which are redeposited onto the tooth surface to rebuild the crystalline structure after it has been challenged by acids. This dynamic exchange keeps the teeth strong and resistant to decay.
Saliva also contains a buffering system, primarily involving bicarbonate ions. This system works to neutralize acids produced by oral bacteria after eating or drinking, quickly raising the pH level in the mouth. When the oral environment drops below a pH of 5.5, the enamel begins to demineralize, but the buffering capacity of saliva helps quickly restore the pH to a neutral range. The fluid also provides lubrication via mucins, protecting soft tissues and aiding in speech and swallowing.
Common Causes of Oral Dehydration
When saliva production is disrupted, the protective and reparative functions diminish, leading to a state of oral dehydration known as xerostomia. A significant number of common medications can interfere with the signals sent to the salivary glands, causing reduced flow. These include tricyclic antidepressants, SSRIs, antihistamines, and certain blood pressure medications like diuretics. Taking multiple medications simultaneously further increases the likelihood of this side effect.
Systemic health conditions can also directly impair the salivary glands’ ability to function. Autoimmune disorders such as Sjögren’s syndrome involve the immune system attacking the moisture-producing glands, leading to chronic dry mouth and eyes. Additionally, poorly managed conditions like diabetes can affect nerve function and fluid balance, contributing to a persistent lack of saliva.
Another common factor is mouth breathing, particularly during sleep, which leads to excessive evaporative moisture loss. When air bypasses the humidifying action of the nasal passages, it dries out the oral tissues and the teeth’s surface, concentrating residual acids. Insufficient overall water intake can also contribute to the problem, as the body will prioritize water for vital organs, reducing the fluid available for saliva production.
Actionable Strategies for Maintaining Oral Hydration
An immediate and effective method to improve oral hydration is to stimulate the natural production of saliva. Chewing sugar-free gum, especially those containing the sugar alcohols xylitol or sorbitol, significantly increases salivary flow. Xylitol is particularly beneficial because oral bacteria cannot metabolize it into enamel-eroding acids, promoting a healthier oral environment.
Sipping plain water frequently throughout the day is a simple strategy that helps dilute the concentration of mouth acids and supports systemic hydration. Consuming water-rich foods like cucumber and watermelon contributes substantially to the body’s fluid intake. The physical act of chewing fibrous, crunchy fruits and vegetables also stimulates saliva flow while naturally cleansing the tooth surfaces.
External aids can provide direct relief and a protective coating for the teeth and gums. Over-the-counter saliva substitutes are available as sprays, gels, or lozenges and are formulated with ingredients like glycerin or carboxymethylcellulose to mimic the lubricating texture of natural saliva. Many of these products are enriched with minerals like calcium, phosphate, and sometimes fluoride, which reinforce the remineralization process.
It is beneficial to minimize the consumption of beverages that act as diuretics. Both alcohol and caffeinated drinks increase urine output, pulling fluid away from tissues, including the salivary glands. For individuals with chronic dryness, switching to a moisturizing mouthwash or toothpaste that is alcohol-free and contains agents like xylitol can help manage symptoms without causing further irritation.