Dentinal hypersensitivity, often called sensitive teeth, is a common dental problem characterized by a sudden, sharp pain or discomfort in one or more teeth. This sensation typically occurs when teeth are exposed to specific triggers like hot, cold, sweet, or acidic substances. The pain experienced with dentinal hypersensitivity is usually bothersome and interferes with daily activities such as eating or drinking.
What Causes Dentinal Hypersensitivity?
Dentinal hypersensitivity arises when the protective outer layers of the tooth, enamel on the crown and cementum on the root, wear away or recede, exposing the underlying dentin. Dentin is a porous tissue containing thousands of microscopic channels called dentinal tubules, which lead directly to the tooth’s nerve center, the pulp. When these tubules are exposed, external stimuli can cause fluid movement within them, triggering nerve endings and resulting in a sharp pain. This phenomenon is explained by the hydrodynamic theory.
Several factors contribute to the exposure of dentin. Gum recession, where the gum tissue pulls away from the tooth, is a primary cause, often exposing root surfaces covered by a thinner, less protective layer of cementum. Aggressive tooth brushing can wear down enamel and cause gums to recede.
Enamel erosion, the loss of hard dental tissues due to acids, also plays a role. This can result from frequent consumption of acidic foods and drinks, or from medical conditions like gastroesophageal reflux disease (GERD) or bulimia. Tooth grinding, or bruxism, can also gradually wear down enamel, exposing the dentin.
Recognizing Symptoms and Common Triggers
The hallmark symptom of dentinal hypersensitivity is a sharp, sudden pain that typically lasts for a short duration. This discomfort is a direct response to specific external stimuli.
The most frequently reported trigger is cold, including cold drinks, food, or even cold air. Other common triggers include hot foods and drinks, sweet or sugary substances, and acidic foods like citrus fruits or vinegar. Mechanical–tactile stimuli, such as brushing, flossing, or a dental probe during an examination, can also elicit pain.
Managing and Treating Dentinal Hypersensitivity
Alleviating and treating dentinal hypersensitivity involves both at-home approaches and professional dental interventions.
At-Home Care
Desensitizing toothpastes are a common recommendation. These toothpastes often contain ingredients like potassium nitrate, potassium chloride, or potassium citrate, which work by blocking nerve signals or physically occluding the dentinal tubules, thus reducing fluid movement and pain transmission. Consistent use over time can help build a protective barrier and offer long-term relief.
Using a soft-bristled toothbrush and employing a gentle brushing technique can prevent further wear on enamel and gum recession. Proper oral hygiene, including regular brushing and flossing, helps remove plaque and reduce the risk of gum inflammation, which can contribute to sensitivity.
Professional Treatments
Dentists may apply fluoride varnishes or gels to strengthen tooth enamel and reduce sensitivity. Dentin bonding agents can be applied to cover and protect exposed dentin surfaces. For significant gum recession, a surgical gum graft may be performed to cover the exposed root surfaces. For severe and persistent sensitivity that does not respond to other treatments, a root canal may be considered to eliminate the pain.
Preventing Dentinal Hypersensitivity
Preventing dentinal hypersensitivity involves maintaining good oral hygiene practices and making mindful dietary choices. Brushing teeth gently twice a day with a soft-bristled toothbrush helps protect enamel and prevent gum recession. Limiting the consumption of highly acidic foods and drinks, such as sodas, citrus juices, and vinegars, is beneficial, as these can erode tooth enamel over time.
If acidic foods or drinks are consumed, rinsing the mouth with water afterwards can help neutralize the acids. Addressing habits like teeth grinding, possibly through the use of a nightguard, can prevent enamel wear that leads to sensitivity. Regular dental check-ups are also important, as dentists can identify early signs of problems and provide guidance or early interventions.