Chewing gum has long been debated in dental health circles, leaving consumers unsure if the habit helps or harms their teeth. The answer depends entirely on the type of gum being chewed. Traditional gum containing sugar poses a genuine threat to oral health, while modern sugar-free varieties offer measurable protective benefits. Understanding these differences is the first step in determining how chewing affects your smile.
The Risk of Traditional Sugared Gum
Gum containing sugar actively contributes to the development of dental caries, commonly known as cavities. When sugared gum is chewed, the dissolved sugar becomes a primary food source for mouth bacteria, particularly Streptococcus mutans. These bacteria metabolize the sugar through fermentation, releasing acid onto the tooth surface.
This acid lowers the pH level in the mouth, initiating demineralization, where minerals are leached from the protective tooth enamel. The constant presence of sugar extends the duration of this acid attack, weakening the enamel over time. Frequent exposure to these acidic conditions increases the likelihood of plaque formation and the eventual creation of a cavity.
Protective Benefits of Sugar-Free Gum
The act of chewing significantly increases the rate of saliva production, which is the primary mechanism of protection. Chewing sugar-free gum can increase salivary flow by as much as 10 to 12 times the normal resting rate. This stimulated saliva acts as a natural buffer, neutralizing acids produced by plaque bacteria and quickly raising the mouth’s pH level back to a safe zone.
The increased flow of saliva also helps to physically wash away food debris and sugars from the teeth. Saliva carries essential minerals, such as calcium and phosphate, which are delivered back to the enamel to encourage remineralization. This process helps repair microscopic damage caused by acid attacks before it progresses into a cavity.
Certain sugar alcohols, such as Xylitol and Sorbitol, provide an additional defense against decay. Xylitol is non-cariogenic, meaning decay-causing bacteria cannot metabolize it for energy. This starves the bacteria and reduces the load of S. mutans, the species most responsible for acid production. Sorbitol and other non-sugar sweeteners contribute by not lowering the plaque pH below the level necessary for enamel dissolution.
Mechanical Effects on Dental Structure
While the chemical effects of sugar-free gum are beneficial, the physical act of chewing introduces mechanical considerations. Prolonged chewing engages the masticatory muscles, including the masseter, for extended periods. This continuous, repetitive motion can lead to muscle fatigue, tightness, and jaw spasms.
For individuals suffering from a temporomandibular joint disorder (TMD), the habit can exacerbate existing symptoms like jaw pain, clicking, or difficulty opening the mouth. The added stress on the temporomandibular joint may worsen inflammation and discomfort. Dental professionals often advise people diagnosed with TMD to avoid chewing gum entirely to prevent further strain.
Chewing gum can also pose a risk to existing dental restorations and appliances. The sticky nature of the gum base may pull on loose fillings, crowns, or bridges, potentially dislodging them. Individuals with orthodontic appliances, such as braces, are advised to avoid gum because it can become trapped in the wires and brackets, making cleaning difficult and potentially damaging the hardware.
Guidelines for Chewing Gum Safely
To maximize benefits and minimize risks, selecting the correct product is important. Always choose gum explicitly labeled as sugar-free, and ideally, look for products that carry the American Dental Association (ADA) Seal of Acceptance. The ADA seal confirms the gum meets standards for safety and effectiveness in reducing the risk of cavities.
The optimal time to chew sugar-free gum is immediately following a meal or snack. This timing utilizes the heightened salivary flow to quickly neutralize acids produced after eating and wash away residual food particles. Clinical studies suggest that chewing for approximately 20 minutes is effective for increasing saliva production and acid neutralization.
It is important to limit the duration of chewing to prevent overworking the jaw muscles and joints. Excessive chewing contributes most to mechanical strain and potential TMD issues. Chewing gum should be viewed as a supplemental tool for oral hygiene, not as a replacement for regular brushing and flossing.