Biting the inside of your cheek, whether a sudden accident or a recurring habit, is a common and painful experience. While the immediate sensation is alarming, an occasional cheek bite is generally not a serious medical concern. The soft tissues of the mouth have a remarkable capacity for healing, and most simple injuries resolve quickly. However, when the biting becomes chronic, it can lead to persistent issues that warrant attention from a dental or medical professional.
Immediate Physical Aftermath
Acute pain following a cheek bite results from trauma to the buccal mucosa, the delicate lining inside the mouth. This injury often leads to an immediate, painful, reddish lesion that may bleed slightly. Within hours, the area typically develops a traumatic ulcer, appearing as a shallow sore with a whitish or yellowish surface surrounded by a red border.
This yellowish-white film is a protective layer of dead cells and fibrin, not pus. Swelling (edema) is also common as the body rushes inflammatory cells to the site of injury. Most simple traumatic ulcers heal fast due to the mouth’s excellent blood supply and regenerative properties. A typical cheek bite injury will become painless within about three days and heal completely within 7 to 10 days, provided the area is not repeatedly re-injured.
Understanding Why Cheek Biting Happens
Cheek biting is categorized as accidental or chronic, habitual behavior. Accidental biting is usually related to sudden events, such as chewing food too quickly, talking while eating, or jaw misalignment following a dental procedure. Dental factors like misaligned teeth, sharp edges on a broken tooth, or ill-fitting dentures can also create a persistent point of accidental contact.
Habitual or chronic cheek biting is known medically as morsicatio buccarum. This behavior is often classified as a body-focused repetitive behavior (BFRB), similar to nail-biting, and is frequently a response to stress, anxiety, or boredom. The behavior can be semi-conscious (the person is aware but struggles to stop) or occur unconsciously, particularly during sleep, which may be related to teeth grinding (bruxism). Identifying the underlying cause, whether mechanical or psychological, is the first step toward effective management.
Potential Long-Term Concerns
When cheek biting becomes chronic, the repeated trauma can lead to noticeable changes in the oral tissue. The soft tissue can develop a horizontal, thickened white line along the inner cheek where the upper and lower teeth meet, a condition called Linea Alba. This is essentially a callus that forms due to friction and is usually harmless, but the raised tissue can make the cheek more prone to being bitten again.
In cases of severe, chronic chewing, the constant irritation can result in the formation of scar tissue or a small, non-malignant lump called an irritational fibroma. A rare concern is the potential link between chronic mechanical irritation (CMI) and oral cancer. While cheek biting alone is not considered a direct cause, a chronic, non-healing wound might promote the progression of existing cancer or increase risk in individuals who also engage in high-risk behaviors like tobacco or excessive alcohol use. Any ulcer or sore that persists for longer than two weeks after the source of irritation is removed requires a professional evaluation to rule out more serious pathology.
Treating Injuries and Breaking the Habit
For an acute cheek bite injury, simple home care promotes healing and minimizes discomfort. Rinsing the mouth several times a day with a warm saltwater solution (half a teaspoon of salt in a cup of warm water) helps keep the area clean and soothes the wound. Avoiding irritating foods, such as those that are spicy, acidic, or crunchy, will prevent further trauma to the tender tissue. Over-the-counter topical gels containing benzocaine or antiseptic mouthwashes can offer temporary pain relief.
Breaking a habitual biting pattern often requires a multi-pronged approach that addresses both the physical and psychological triggers.
Addressing Mechanical Causes
If the issue is related to dental alignment, a dentist can smooth sharp teeth, adjust dental appliances, or recommend orthodontic treatment. For unconscious nocturnal biting, a custom-fitted mouthguard can provide a protective barrier between the teeth and the cheek.
Addressing Psychological Causes
When the habit is driven by anxiety, stress management techniques like mindfulness, deep breathing exercises, or professional help through cognitive behavioral therapy (CBT) can substitute the biting behavior with a healthier coping mechanism.