What Causes Mouth Ulcers in Kids: Little Mouths, Big Questions

May 1, 2024


In the realm of pediatric dentistry, parents often find themselves confronted with a perplexing dilemma: the appearance of mouth ulcers in their young children. These seemingly minor yet painful sores can disrupt daily life, prompting caregivers to seek answers and solutions. Delving into the underlying causes of mouth ulcers in kids is crucial for providing adequate care and relief.

Understanding Mouth Ulcers in Kids:

Mouth ulcers, medically termed aphthous ulcers or canker sores, manifest as small, round lesions on the soft tissues inside the mouth. In children, these ulcers can cause significant discomfort, making eating, drinking, and speaking challenging. Typical symptoms include redness, swelling, and tenderness in the affected area. While the exact cause of mouth ulcers remains elusive, several factors may contribute to their development.

Common Causes of Mouth Ulcers in Kids:

Dietary Factors:

  • Consumption of acidic or spicy foods: Certain foods, such as citrus fruits, tomatoes, and spicy snacks, may irritate the delicate tissues of the mouth, forming ulcers.
  • Deficiency in specific vitamins and minerals: Insufficient intake of essential nutrients like vitamin B12, iron, or folate can compromise oral health, making children more susceptible to mouth ulcers.

Oral Hygiene Practices:

  • Trauma or injury from aggressive tooth brushing: Vigorous brushing or the use of hard-bristled toothbrushes can damage the delicate tissues of the mouth, leading to the development of ulcers.
  • Use of harsh or abrasive oral care products: Certain toothpaste or mouthwash formulations containing abrasive ingredients may exacerbate oral irritation, contributing to the formation of ulcers.

Environmental Triggers:

  • Stress or anxiety: Psychological or emotional tension can weaken the body’s immune response, making children more vulnerable to oral infections and ulcers.
  • Allergies to certain foods or substances: Sensitivity or allergy to specific food ingredients, additives, or environmental allergens may trigger inflammatory reactions in the mouth, resulting in ulcers.

Teething and Mouth Ulcers:

Teething, the natural process of primary tooth eruption in infants, is often accompanied by a range of oral symptoms, including drooling, gum swelling, and irritability. While teething does not directly cause mouth ulcers, it can exacerbate oral discomfort, making children more susceptible to developing ulcers. During the teething phase, children may experience increased saliva production and a tendency to chew on objects, which can further irritate the delicate tissues of the mouth.

Medical Conditions and Mouth Ulcers:

In some cases, underlying medical conditions or systemic factors may predispose children to recurrent mouth ulcers. These conditions may include:

  • Autoimmune disorders: Conditions such as celiac disease, inflammatory bowel disease (IBD), or Behçet’s disease are characterized by immune system dysfunction, which can lead to chronic inflammation and ulceration in the mouth.
  • Viral infections: Certain viral infections, including herpes simplex virus (HSV) and hand, foot, and mouth disease (HFMD), can cause oral lesions and ulcers in children.

Preventive Measures for Mouth Ulcers in Kids:

Prevention is critical to minimizing the occurrence and severity of mouth ulcers in children. Parents and caregivers can take the following preventive measures to promote oral health and reduce the risk of ulcers:

  1. Maintain a balanced diet: Encourage children to eat a variety of fruits, vegetables, healthy grains, and lean meats to ensure they receive enough important nutrients.
  2. Practice good oral hygiene: Teach children proper brushing and flossing techniques and ensure they use soft-bristled toothbrushes and mild, non-abrasive toothpaste.
  3. Identify and avoid potential triggers: Pay attention to any dietary or environmental factors that exacerbate oral irritation or trigger ulcer formation, and take steps to minimize exposure.
  4. Manage stress: Assist children in developing appropriate coping methods for stress and anxiety, such as relaxation techniques, physical exercise, and honest communication.

When to Seek Medical Attention:

While most mouth ulcers in children resolve on their own within a week or two, parents should seek medical attention from a dental office in Modesto if:

  • The ulcers persist for more than two weeks or recur frequently.
  • The child experiences severe pain, difficulty eating or drinking, or high fever.
  • Infection symptoms include swelling, redness, and pus discharge from ulcers.

pediatric dentist in Modesto, CA, may do a complete assessment and propose suitable treatment choices for chronic or severe mouth ulcers in children.

Tips for Soothing Mouth Ulcers in Kids:

While waiting for mouth ulcers to heal, parents can provide comfort and relief to their children by implementing the following tips:

  1. Offer soft, bland foods: Choose meals that are simple to chew and swallow, such yogurt, applesauce, mashed potatoes, and scrambled eggs.
  2. Provide excellent, soothing liquids: Offer water, milk, or herbal teas to help hydrate the mouth and alleviate discomfort.
  3. Use over-the-counter remedies: Apply topical oral gels or ointments containing benzocaine or lidocaine to numb the affected area and reduce pain.
  4. Avoid irritants: Encourage children to avoid acidic or spicy foods and rough or crunchy snacks that may aggravate mouth ulcers.


Comprehending what causes mouth ulcers in kids is vital for their oral health and overall well-being. By tackling dietary, hygiene, and environmental factors, parents can reduce the likelihood of ulcer development and ensure proper care for their children. If you’re worried about your child’s mouth ulcers or seek advice on prevention and treatment, contact 123 iSmile, your trusted pediatric dentist. Let’s work together to nurture a healthy smile and a happy child!

Click to listen highlighted text!