What are the primary causes of dental enamel erosion?

Causes of Dental Enamel Erosion

Dental enamel erosion is caused by two primary mechanisms: acid-mediated demineralization from dietary sources (exogenous acids) and gastric acid exposure (endogenous acids), with acidic beverages being the most significant dietary culprit.

Primary Exogenous (Dietary) Causes

Acidic Beverages

• Carbonated/soft drinks are the main dietary factor associated with erosive tooth wear, confirmed by systematic reviews 1
• Sugar-containing acidic drinks are particularly damaging because they contribute both acid erosion and bacterial acid production from sugar fermentation 2
• Sports drinks pose significant erosion risk due to their low pH and high titratable acidity 1, 3
• Frequent consumption of natural fruit juices is significantly associated with increased erosive tooth wear 1

Acidic Foods

• Vitamin C supplements and acidic snacks or sweets are significantly associated with more erosive tooth wear 1
• Fermented foods (such as Japanese pickles) can contribute to erosion despite their nutritional benefits 3

Chemical Mechanism of Dietary Erosion

• Enamel dissolution occurs when substances are undersaturated with respect to tooth minerals, having low pH, high titratable acidity, and high buffer capacity 1
• The erosive potential depends on multiple chemical parameters: pH, buffer capacity, titratable acidity, viscosity, and concentrations of calcium, phosphate, and fluoride 1
• Swishing acidic drinks in the mouth increases erosion by continuously renewing the Nernst layer, preventing saturation 1

Primary Endogenous (Internal) Causes

Gastric Acid Exposure

• Gastrointestinal disorders expose teeth to frequent contact with highly acidic gastric content 4
• Eating disorders (such as bulimia) cause repeated exposure to gastric acid through vomiting 4, 5
• Gastroesophageal reflux disease (GERD) is a significant cause of erosion in affected patients 5

Bacterial Acid Production (Distinct from Erosion)

It is critical to distinguish erosion from dental caries, as these are separate pathological processes 6:

• Dental caries results from bacterial fermentation of sugars in dental plaque, producing acid that demineralizes enamel 2
• Caries begins as subsurface demineralization, while erosion is primarily a surface phenomenon 6
• These two pathologies rarely occur simultaneously at the same site 6

Protective Factors

• Higher consumption of milk and yogurt protects against erosive tooth wear 1
• Substances with high concentrations of calcium and phosphate cause less demineralization 1
• Fluoride presence in saliva and plaque can enhance remineralization of early demineralized enamel, though this primarily prevents caries rather than erosion 2

Clinical Pitfalls to Avoid

• Do not misdiagnose erosion as caries - erosion requires direct acid contact with enamel, while caries requires bacterial plaque biofilm 6
• Erosion is relatively rare and occurs only in susceptible individuals, despite widespread consumption of acidic foods and beverages 6
• Susceptibility varies widely between individuals due to multifactorial causes including saliva composition, oral hygiene practices, and consumption patterns 4, 6
• Assess complete dietary intake using a diet record sheet for any patient presenting with erosive tooth wear, documenting both the erosive potential of beverages/foods and frequency of ingestion 1