Factors in the Dental Caries Process

Diagram showing the factors in the dental caries process

The etiology of dental caries is a dynamic process that involves a susceptible tooth, cariogenic bacteria in dental biofilm (Streptococcus mutans and lactobacillus), and the detrimental effects of cariogenic carbohydrates. Modifying factors also include the absence of fluoride, xerostomia, and inadequate oral hygiene. The demineralization process during an acid attack and subsequent remineralization by saliva and fluoride happens continuously throughout the day. Studies demonstrate it can take approximately 19 to 22 months for the cavitation process to progress to the dentin, making the caries process complex and continuous.11 Our role as oral health educators is to analyze dietary habits and causative factors to determine a patient’s risk for dental caries. The chart below is a guide to assess a patient’s risk factors for the development dental caries.11

Chart to assess a patient’s risk factors for the development dental caries

Each time food is consumed there is an opportunity for bacteria to produce an acid and begin the caries process. In fact, the frequency of sugar eaten is a primary factor in a patient’s risk assessment. Sugary foods or liquids allows for separate opportunities for bacteria to feed and produce acid. Within 3 minutes of eating a cariogenic food, the pH of the dental plaque falls below 5.5 and the caries process begins. Once food clears the mouth, pH gradually returns to neutral, between 6.8-7.0. The goal is to prevent demineralization by keeping the oral pH neutral for as long as possible. Cariostatic foods are those that do not contribute to enamel demineralization and maintain a basic pH balance. Eating foods rich in protein, lipids, phosphorus and calcium such as meat, milk, cheese, and nuts can help neutralize acids. Brushing the teeth or rinsing with water after eating a cariogenic carbohydrate can also help neutralize acids.11

Stephen curve demonstrating how each eating and drinking event drops the critical pH of the mouth below 5.5

Stephen curve in the photo above, named after Dr. Robert Stephan, demonstrates how each eating and drinking event drops the critical pH of the mouth below 5.5 which initiates the demineralization process.

Destructive effects of soda, juice, and the popular energy drinks are a major cause of early childhood caries and decay among both children and teenagers, especially in low income and minority populations. One 12-ounce soda contains 10 teaspoons of sugar as well as acid. Diet soda and energy drinks includes both citric and phosphoric acid, which may cause direct demineralization of the tooth enamel. Rinsing the mouth with water, bypassing the teeth by using a straw, chewing gum with xylitol, and consuming the potential caries causing drinks with a meal can help reduce the negative effects of liquid fermentable carbohydrates.

Figure 9. Calories and Teaspoons of Sugar in 12 Ounces of Each Beverage.15
Figure 9 is a visual chart relating how much sugar is in a variety of beverages

To combat further the factors in the caries process, remember that water is the superior choice for quenching your thirst. It provides everything the body needs to restore fluid lost through metabolism, breathing, sweating, and removal of waste. Fluoride in both food and water will also help remineralize tooth enamel.

To help increase your water consumption and infuse a bit of flavor, try;

  • Slicing citrus fruits or zest.
  • Crush fresh mint leaves.
  • Add a slice of ginger.
  • Crush berries.
  • Add a splash of sparkling juice.