Dental Erosion

Key Points

  • Dental erosion is a chemical process characterized by acid dissolution of dental hard tissue not involving acids of bacterial origin.
  • Erosive demineralization can result in progressive, irreversible loss of tooth mineral substance, and may be caused by intrinsic (e.g., acid reflux and excessive vomiting) and/or extrinsic (e.g., dietary) factors.
  • Frequent consumption of soft drinks, particularly carbonated sodas, is a primary risk factor for erosive tooth wear. Consumption of acidic snacks/sweets or natural acidic fruit juice may also increase risk for erosion.
  • Diagnosis and management of dental erosion includes careful clinical examination and evaluation of the patient to identify common signs of erosion (e.g., loss of enamel texture, cupping or flattening on occlusal surfaces), predisposing factors for erosive tooth wear, and options to reduce probability of exposure to erosive (acidic) drinks, dietary sources and/or other acids of intrinsic or extrinsic origin.



Dental erosion, also known as tooth erosion, is the chemical loss of mineralized tooth substance caused by exposure to acids not derived from oral bacteria.1 Erosive demineralization is a chemical process characterized by acid dissolution of dental hard tissue, and its etiology is multifactorial.2-6

The primary etiologic factors of dental erosion are acids of intrinsic (often due to acid reflux) or extrinsic origin (diet, particularly carbonated/soft drinks or acidic fruit-juice consumption; exposure to industrial or environmental chemicals).3, 4, 7, 8 Beyond aesthetic consequences and associated oral health issues, severe erosive activity can lead to exposed dentin, hypersensitivity, and eventual loss of affected teeth.9-12

Dental erosion can occur in individuals of any age.13, 14 One global prevalence study estimated that the mean prevalence of erosion in deciduous teeth ranges between 30% and 50%, and the mean prevalence of erosion in permanent teeth in adults ranges between 20% and 45%.14 The same study also reported selective and highly variable data on erosion prevalence in children, adolescents and adults, due to variation in erosion indices, populations examined, regional diets/customs and study design.14 A 2015 meta-analysis13 indicated that 34.1% of 16,661 children and adolescents worldwide exhibited dental erosion. In the U.S., an analysis of data from the National Health and Nutrition Examination Survey (NHANES, 2003-2004) estimated an erosive tooth wear prevalence of 45.9% among children15 and up to 80% among adults.16

Dental Erosion

Intrinsic Causes

Intrinsic erosion results from the introduction of gastric acids into the oral cavity at a frequency, duration and/or intensity that exceed the ability of the buffering capacity of saliva or other oral health measures to minimize an erosive challenge, usually several times a week for an extended period of time.7, 13  Stomach acid may reach the oral cavity in cases of gastroesophageal reflux disease (GERD), a common condition in which gastric contents reflux back up into the esophagus and/or the mouth. Other erosive challenges from gastric acid occur from recurrent vomiting, such as occurs in bulimia nervosa, chronic alcoholism, and pregnancy, when it is referred to as hyperemesis gravidarum.2, 4, 7, 17

  • Gastroesophageal reflux. Gastroesophageal reflux disease is considered a predisposing factor for dental erosion due to chronic regurgitation of gastric contents. Some systematic reviews report that severity of erosive tooth wear may be associated with the frequency and/or intensity of acid regurgitation.18-20 Occasional regurgitation of stomach acids following meals, especially after overeating, is considered normal7, 13 for up to about one hour a day.4 However, in people with GERD, the passage of gastric acids into the oral cavity during sleep is especially damaging to the teeth, as salivation and swallowing are reduced, and, in a supine position, the lower molars can be bathed in the acids.4 Increases in intra-abdominal pressure (i.e., from obesity or pregnancy) may also increase reflux,7 and GERD has been found to be a common comorbidity of several chronic respiratory conditions.21-23 

    Two common symptoms of GERD are heartburn and/or acid regurgitation, and additional manifestations of GERD include dysphagia, dyspepsia, hoarseness of voice, abdominal pain, or an acidic taste (or burning sensation) in the mouth or throat.24-27 Dysregulation of gastrointestinal enzymes and hormones and impaired reflux clearance have been identified as two potentially important contributors to GERD development.28, 29

    Prevalence rates of GERD across all age groups reportedly ranges from 9% to 33%, with some evidence suggesting an increase in GERD prevalence in the United States since 1995.30 One systematic review determined that the mean prevalence of erosion in adult patients with GERD was 32.5% (range: 21-83%) and 17% among children with GERD (range: 14-87%).31 Additionally, one meta-analysis concluded that individuals with at least weekly symptoms of GERD have up to five times higher risk of esophageal adenocarcinoma.32   

Figures, below. Moderate to severe erosion from GERD in the primary dentition.

erosion molarserosion molars
Photos courtesy of Martha Ann Keels, D.D.S., PhD
  • Bulimia. Bulimia nervosa is a serious eating disorder that is characterized by self-induced vomiting as a means to maintain a desired weight.4, 7, 33 It is a relatively common disorder among women in Western industrialized nations, with a prevalence of approximately 5% in 18-35 year-old females.7 Among individuals with bulimia, the prevalence of erosion has been reported to be over 90%.7 Individuals with bulimia or other eating disorders are commonly found to have poor oral health, with one systematic review finding that patients with eating disorders and/or self-induced vomiting had five to seven times higher risk of dental erosion.34 Because patients with bulimia are generally of average weight, dentists are often the first to recognize the condition by the characteristic erosion of the lingual-palatal aspect of the anterior maxillary teeth (i.e., perimolysis or perimylolysis, see photos below),4, 7 caused by the forceful expulsion of stomach acids onto the front teeth during vomiting.

Figures, below. Characteristic erosion pattern from bulimia.

Exterior view of enamel erosion of the lingual-palatal aspect of the anterior maxillary teeth (i.e., perimolysis or perimylolysis)Internal view of enamel erosion of the lingual-palatal aspect of the anterior maxillary teeth (i.e., perimolysis or perimylolysis)
Photos courtesy of Craig Mabrito, D.D.S.
  • Chronic Alcoholism. Alcoholism, with a prevalence of around 10% in Western countries,7 can result in erosive tooth wear when there is frequent vomiting and/or increased regurgitation7, 35 or even when alcohol consumption is low-dose but long-term.36 In addition, erosion in individuals with alcoholism can also be exacerbated by the consumption of acidic drinks.10, 17 Small studies have found between 49 – 92% of the teeth in individuals with alcoholism show signs of erosion.7, 36 As in bulimia, the palatal surfaces of anterior maxillary teeth tend to be the most affected in alcoholic patients, who were also found to have relatively high erosion severity on the occlusal and palatal surfaces of the posterior, and incisal edges of the anterior, maxillary teeth.7, 35, 36

  • Pregnancy. Although dental erosion is rare in pregnancy, it has been reported in women who experience hyperemesis gravidarum,7 where the nausea and vomiting may be experienced over a longer period of time and may be more severe.37

Extrinsic Causes

Erosion due to extrinsic factors may arise from a combination of dietary, lifestyle, environmental or occupational factors that expose teeth to acids in beverages2, 3, 5 or inorganic acid vapors in the environment.2, 5

  • Beverages. A growing body of evidence suggests that the primary predisposing factor for extrinsic dental erosion2, 4, 13 is frequent consumption of soft drinks, sports drinks and fruit juices with low pH values (2.0-3.5).4, 5 Any beverage with a low pH can increase risk for erosion,4 especially with frequent consumption.2, 4, 5, 17, 38Although wines, for example, are naturally acidic, they are not commonly cited as a risk factor for erosion because they are typically not consumed as frequently as sports drinks and diet sodas.5 In 2016, a study by Reddy et al. measured the pH of 379 commercially available beverages available in the U.S., and found that 93% had a pH of less than 4.0.39

    A number of studies6, 13, 17, 40 support the hypothesis that dietary acids are a major contributing factor in dental erosion.7, 41 A 2012 meta-analysis found more than double the risk of erosion from soft drinks as well as an increase in risk from chewable vitamin C tablets.40 Other studies, including a 2015 meta-analysis, determined that natural fruit juices as well as carbonated soft drinks and acidic, sweet snacks and sweet-sour candies were significant predisposing factors for erosion.13, 42

  • Lifestyle. More frequent consumption of highly acidic fruit and sport drinks, in combination with decreased salivary flow and dehydration from athletic or strenuous activity, may increase erosion risk.3 Intense workouts may also increase the possibility of gastroesophageal reflux.3 Although there is some evidence that a vegetarian diet and excessive use of vinegar-based dressings may lead to increased erosion,43-45 a critical analysis of this topic noted that the evidence on erosivity of vegetarian diets has significant limitations and is relatively weak in overall quality.46

  • Environmental and Occupational Risks. Airborne industrial acids have been implicated in dental erosion among factory workers,2, 3 particularly in munitions, battery, and fertilizer plants.3 Swimmers frequenting chlorinated swimming pools have been reported to have increased levels of erosion, attributed to the water’s pH.2, 3, 10

Diagnosis, Prevention, and Management

Erosive tooth wear may be diagnosed by integrating a review of findings from a detailed health history, assessment of relevant risk factors, and a comprehensive clinical examination.1 The process of erosive tooth wear begins with initial softening of the enamel surface with subsequent and/or progressive loss of volume, with a softened layer (i.e., less surface hardness) remaining at the mineralized tooth surface.47 Individuals with erosion may also present with dentition that has loss of enamel texture and/or a silky, glossy or “melted” appearance, with cupped, flattened or smoothed occlusal surfaces (or without the sound morphology of natural dentition).1, 27, 48

A detailed health history-taking process can help identify high-risk conditions (e.g., GERD, bulimia) or underlying causes that can elevate risk of exposure to acid erosive challenges, primarily acids of intrinsic (gastric) or extrinsic (dietary) origin. In the oral examination, the dentist may observe common signs of erosive tooth wear, such as shallow defects (typically on smooth surfaces) and cupping or flattening on occlusal surfaces (examples presented in photos in the “Gastroesophageal reflux” section above).1 Additional signs of progressive erosive tooth wear may include dentin hypersensitivity and/or erosive lesions with absence of staining.27, 49 Early diagnosis of dental erosion can be challenging because patients often present without clear or clinically evident symptoms.27

Since dental erosion results in progressive and irreversible loss of mineralized tooth substance, the primary focus of erosion intervention is prevention and reduction, followed by management.17 Clinical management typically includes lifestyle and dietary changes, and, if necessary, restorative treatment to halt progression of erosive lesions.17, 50

Some studies have found that milk and yogurt products (presumably unsweetened) may have a protective effect against erosion13, 17, 40 hypothesized to be due to their calcium and phosphate content.40 While calcium supplemented to acidic beverages, and other calcium-enriched products, have been suggested as protective alternatives to soft and sports drinks,17, 40 the efficacy of this strategy has not been thoroughly investigated. Fluoride may contribute to remineralization of enamel,9, 51 but others have advised that fluoride’s “ability to prevent erosion cannot be presumed.”3

More recently, however, several in situ studies52-59 suggest that fluoride treatments are effective in protecting dental enamel from the effects of erosion, although efficacy varies according to compound or preparation, and further research is needed.

Patient Information
  • Avoid dietary acids between meals, reduce intake of acidic beverages and eliminate behaviors that increase acidic (erosive) challenges to the dentition, particularly swishing or straining the liquid between the teeth, or holding the liquid in the mouth.3, 17, 58, 60 Drinking with a straw positioned behind the front teeth can minimize bathing the teeth.17
  • Drink water while eating, or rinse the mouth with water after consuming acidic drinks, candies, or foods.4, 40
  • After vomiting, rinse the mouth with water, a sodium bicarbonate rinse, or milk.4, 40, 61, 62
  • Saliva helps buffer and remove acids; chewing gum may help protect teeth from erosion by promoting salivary flow.
  • Drink milk along with acidic meals or beverages, which contributes to remineralization and helps neutralize acids. 
  • Rinse with water rather than brushing teeth immediately after consuming acidic beverages.4, 13, 63
  • Brush teeth using a soft-bristle brush and fluoride toothpaste.63 Dental abrasion (physical loss of mineralized tooth substance from objects other than teeth) may potentially occur in rare cases of excessive or aggressive toothbrushing. However, normal toothbrushing practices using a soft-bristle brush and low-abrasion, fluoride-containing toothpaste are considered unlikely to cause erosive wear of enamel.49, 64, 65
ADA Seal of Acceptance: Dental Erosion

Look for the ADA Seal of Acceptance—your assurance that the product has been objectively evaluated for safety and efficacy by an independent body of scientific experts, the ADA Council on Scientific Affairs. A company earns the ADA Seal for a product to help prevent or reduce enamel erosion from dietary acids by providing scientific evidence demonstrating the safety and efficacy of its product, which is evaluated according to objective requirements related to the product’s claims.

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Topic last updated: August 31, 2021

Prepared by:

Department of Scientific Information, Evidence Synthesis & Translation Research, ADA Science & Research Institute, LLC.


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