Thyroid conditions present oral and systemic manifestations that can challenge even the most seasoned dental professionals. Up to 15% of the general population has some form of thyroid abnormality, and many people have never been properly diagnosed - which makes treating them all the more complicated.

As a registered dental hygienist, there are ways you can help to identify and manage the oral manifestations of thyroid diseases. Here, we’ll discuss two of the most common thyroid diseases you’ll see in your practice: hypothyroidism and hyperthyroidism.

Oral Manifestations of Hypothyroidism

Hypothyroidism, also called underactive or low thyroid, is a decrease in the hormone production and functioning of the thyroid gland. Hypothyroidism most often affects women from middle age onward, but it can occur in people of any age.

Many people who have hypothyroidism present only a few or very mild symptoms. However, those with severe hypothyroidism can experience numerous symptoms including slow metabolism, weight gain, lethargy, sensitivity to cold, and puffiness of the face.

When treating a dental patient with hypothyroidism, you may notice one or more of the following common oral manifestations:

• Salivary gland enlargement
• Compromised periodontal health
• Glossitis, or inflammation of the tongue marked by soreness, swelling and change in colour

People who experience severe hypothyroidism as a child may present long-term dental and craniofacial manifestations in adulthood, such as:

• Enamel hypoplasia
• Micrognathia, or undersized jaw
• Mouth breathing
• Thick lips
• Macroglossia, or oversized tongue

Oral Manifestations of Hyperthyroidism 

Hyperthyroidism, also called overactive thyroid, is the unregulated production of thyroid hormones. It is most often called by an immune system disorder called Grave’s Disease and usually affects women under 40, but it can occur in people of all ages.

Many of the symptoms of hyperthyroidism mirror hypothyroidism in reverse - sensitivity to heat, weight loss, increased cardiac output are common. It can also cause emotional instability, tremors, abnormal heart rate and hypertension.

A dental patient who has hyperthyroidism may present the following oral manifestations:

• Increased susceptibility to periodontal disease and dental caries
• Enlarged extraglandular thyroid tissue (mainly in the lateral posterior tongue)
• Burning mouth syndrome
• Xerostomia or dry mouth caused by Sjogren's syndrome

Treating Dental Patients Who Have a Thyroid Disease

As a registered dental hygienist, it is important to understand how thyroid dysfunction could affect your patient care.

First, you are well-positioned to notice the symptoms of hypo- or hyperthyroidism and aid in early diagnosis. Your keen eye could be what points a patient in the right direction to receiving treatment for their condition.

For patients who have confirmed thyroid disease, it’s also important that you and your colleagues deliver care that will help, not harm. Complications can occur from improperly treating dental patients with thyroid disorders.

Rebecca Marie Friend, BS, RDH demonstrates this perfectly in a recent column for Today’s RDH. When an elderly patient came in presenting with hypothyroidism, Rebecca took the time to carefully review the patient’s health history and discuss the patient’s medications, including over-the-counter remedies. Not only did this discussion reveal an important oversight by the patient’s doctor, but Rebecca was able to provide the patient with a better understanding of the condition.

Rebecca also provides the following recommendations to hygienists and other dental professionals in treating dental patients who present with thyroid disorders.

1. Establish communication with the patient’s endocrinologist and other healthcare providers. This will ensure that you are kept up to date with the patient’s medications and the rest of the healthcare team is aware of the patient’s oral manifestations.
2. Plan treatment in a way that limits stress and infection. Patients with hypothyroidism are at greater risk of infection due to increased bleeding and delayed wound healing.
3. Treat the oral manifestations of hypothyroidism and hyperthyroidism as needed, including periodontal disease, caries and xerostomia.
4. Conduct an extraoral head and neck examination at each appointment. This will help you detect changes to the patient’s thyroid region.
5. Be sure to always use a thyroid collar when taking patient X-rays. The thyroid gland is very sensitive to radiation, and excessive exposure is a known risk factor for thyroid conditions.
6. Help the patient feel comfortable in the chair. People who have hypothyroidism could use a blanket to help keep their legs warm, while those with hyperthyroidism might appreciate you turning the thermostat down a few extra degrees.