Dentinal hypersensitivity

[drsushant]

Causes of Dentinal Hypersensitivity

The hydrodynamic theory also explains many of the epidemiological observations on the causes of dentinal hypersensitivity.

Brushing Habits

Sustained and overzealous brushing (especially with harder-bristled brushes) is known to thin enamel and cause gingiva to recede, exposing the softer subgingival cementum, which is also damaged by brushing. Right-handed people tend to brush their left teeth more zealously and vice versa, which results in hypersensitivity in those teeth. Also, since people tend to brush the front teeth and outer tooth surfaces more zealously, those areas are more likely to be sensitive than back teeth and inner surfaces, mirroring the incomplete brushing habits of most people.

Tooth Grinding

Patients who grind their teeth experience a higher incidence of dentinal hypersensitivity. This action wears down the enamel on teeth, exposing the dentin.

Gender

Women are more prone to dentinal hypersensitivity. This is because women of any age, generally speaking, are more attentive to basic hygiene than an age-matched group of males. Since this includes dental care, female teeth are more likely to have exposed dentinal tubules as a result.

Age

There is also an age link to dentinal hypersensitivity. The problem does not occur in most people until they reach their late twenties, thirties or forties because overzealous brushing and other factors begin to take their toll at this time.

Diet

Habitual ingestion of acidic substances causes erosion of enamel and dentin, subsequently opening dentinal tubules. The citric acid in citrus fruits (e.g., lemons) dissolves enamel. Similarly, ingestion of other acidic foods and beverages (e.g., ginger ale, which has the lowest pH of any drink commonly available) discussed in this month’s patient information should be avoided whenever possible, since they effectively strip away the tooth’s protective smear layer (a layer of dead organic material that occludes the dentinal tubules, preventing the outward flow of tubular solution). Further, brushing directly after ingestion of these substances causes direct damage to enamel and must be avoided.

Smokeless Tobacco

Users of smokeless tobacco more frequently experience dentinal hypersensitivity. The “quid” of smokeless tobacco placed between the gum and cheek is a well-known cause of gingival recession. As the gingiva recede in response to this noxious chemical, softer subgingival cementum is exposed. Continual brushing erodes the cementum, opening the dentinal tubules.

Disease

There is an increased risk of dentinal hypersensitivity in bulimics and those afflicted with gastroesophageal reflux disease. Both conditions increase intraoral acidity, subsequently causing the type of enamel erosion that leads to dentinal hypersensitivity.

Periodontal disease and gum disease may also result in dentinal sensitivity. With these conditions, the tooth’s root surface is exposed through recession of the gums or loss of supporting ligaments.