Bruxism is the medical term for the grinding, gnashing, or clenching of teeth, a common behavior observed in infants and toddlers. Parents often become concerned when they hear the distinct, sometimes loud, sound of their baby rubbing their teeth together, which can occur during the day or night. This phenomenon is a normal part of oral development and is generally a temporary habit. Understanding the causes of infant bruxism helps determine when the behavior is merely developmental and when it might require attention.
Prevalence and Typical Age of Occurrence
Bruxism is a widespread habit in the pediatric population, with prevalence estimates often falling within the range of 20% to 38% based on parental reports. The onset of teeth grinding most frequently coincides with the eruption of the primary teeth, beginning between six months and three years of age. This behavior is most common when the baby’s mouth is undergoing rapid change as new teeth break through the gums.
The habit tends to diminish spontaneously, often resolving by the time the permanent teeth emerge around age six. Grinding in infants and young toddlers is often classified as sleep bruxism, meaning it occurs unconsciously while sleeping. Some children also exhibit awake bruxism, which is conscious or subconscious grinding while active.
Primary Reasons for Infant Teeth Grinding
Infant teeth grinding is primarily a physiological and developmental response, unlike the psychological causes often seen in adults. One of the most frequent causes is discomfort associated with teething. As new teeth push through sensitive gum tissue, the baby may instinctively grind existing teeth together to create a counter-pressure that temporarily alleviates soreness or irritation.
The act of grinding serves as a form of sensory exploration as the baby learns about their developing mouth structure. With only a few teeth present, the bite is often unstable, and the baby uses grinding to explore new sensations and figure out how the jaws align. This proprioceptive feedback helps the child adjust to the feeling of having teeth and the mechanics of jaw movement. Jaw misalignment, or malocclusion, as the teeth erupt can also prompt the child to grind to find a more comfortable resting position.
The behavior can also be a reaction to pain originating elsewhere in the head and neck. Conditions such as earaches or sinus discomfort may trigger a grinding response as the child attempts to relieve pressure. Stress or changes in routine or overstimulation can also be a factor in some toddlers, leading to clenching or grinding, particularly at night. A family history of bruxism suggests a potential genetic component, making a child more likely to develop the habit.
Addressing Potential Damage and Seeking Professional Guidance
For the majority of infants, occasional teeth grinding poses no long-term threat to the health of their primary teeth. Baby teeth have a naturally softer structure than permanent teeth, but they are designed to withstand wear and are eventually replaced. Persistent and severe grinding can lead to visible tooth wear, where enamel surfaces become flattened or chipped over time.
Parents should monitor for specific signs that may indicate a problem beyond simple developmental grinding. These signs include visible flattening or chipping of the teeth, increased tooth sensitivity to temperature, or facial swelling along the jawline. In older toddlers, complaints of jaw pain, difficulty chewing, or a persistent clicking sound in the jaw joint warrant attention.
A visit to a pediatric dentist or pediatrician is recommended if the grinding is intense or chronic, or if the child displays concerning symptoms. Professional evaluation is suggested if the habit continues past the age of three or four, or if the grinding is severe enough to interfere with sleep. While specific interventions are rarely required for infant bruxism, a dentist can assess the degree of tooth wear and rule out underlying conditions like bite misalignment or temporomandibular joint issues.