Root caries, also known as root decay, refers to decay on the root surface of a tooth. Unlike typical cavities that affect the tooth crown, root caries specifically impact the root, which is covered by a softer substance called cementum, not the tougher enamel. This makes the root more vulnerable to decay. Root caries are increasingly prevalent, particularly among older adults, and can significantly affect oral health.
Causes of Root Caries
The primary factor contributing to root caries is gum recession, which exposes the tooth’s root surface, making it susceptible to bacterial plaque accumulation. When gums recede, the softer cementum and underlying dentin become exposed, lacking the protective enamel found on the tooth crown. These exposed surfaces are then vulnerable to acids produced by specific oral bacteria, such as Streptococcus mutans and Lactobacilli, that metabolize fermentable carbohydrates from food. This acidic environment leads to demineralization, where calcium and phosphate ions are removed from the tooth structure.
Dietary habits also play a significant role, as frequent consumption of sugary and acidic foods and beverages provides a constant fuel source for these acid-producing bacteria. Reduced salivary flow, or dry mouth, diminishes the mouth’s natural ability to wash away food particles, neutralize acids, and remineralize tooth surfaces. This can be a side effect of certain medications, medical conditions, or aging. Gum recession and dry mouth become more common with age, increasing susceptibility to root caries.
Recognizing and Diagnosing Root Caries
Early stages of root caries may not present noticeable symptoms, making regular dental check-ups important for detection. As the decay progresses, individuals might observe discoloration on the root surfaces, appearing brown, yellow, or black. Sensitivity to hot, cold, or sweet foods and beverages can also be a sign. In more advanced cases, visible holes or cavities may form on the root surface, and some individuals might experience localized pain or a constant toothache.
Dentists diagnose root caries through a thorough visual examination and tactile assessment using a probe to check the surface texture. They look for changes in color, contour, and surface cavitation. Dental X-rays may also be used to assess the extent of the decay, especially if it is not readily visible. Early detection allows for less invasive treatment options and helps prevent further damage to the tooth.
Treatment Approaches
Treatment for root caries varies depending on the severity of the decay. For early-stage lesions where the decay has not yet formed a cavity, fluoride treatments are often effective. Professionally applied fluoride varnishes, such as 5% sodium fluoride varnish, or 1.23% fluoride gel, can help remineralize the affected tooth structure. High-concentration fluoride toothpastes, containing 5,000 ppm fluoride, are also recommended for daily home use to promote remineralization and arrest decay progression.
If the root caries have progressed to form a cavitated lesion, dental fillings are commonly used to remove the decayed tissue and restore the tooth’s structure. Materials like composite resin, glass ionomer cement, or amalgam are frequently employed for these restorations. For larger areas of damage that fillings cannot adequately address, inlays, onlays, or dental crowns may be placed to provide more comprehensive coverage and protection.
Should the decay penetrate deeper into the tooth and reach the pulp, root canal therapy becomes necessary to save the tooth. This procedure involves removing the infected pulp and bacteria from inside the tooth, cleaning and shaping the root canals, and then sealing them to prevent future infection. After a root canal, a crown is often placed to protect the treated tooth. In cases of severe damage where the tooth cannot be restored, extraction may be the last resort, sometimes followed by replacement options like dental implants.
Preventing Root Caries
Preventing root caries largely centers on maintaining excellent oral hygiene and managing risk factors. Brushing twice daily with a fluoride toothpaste, such as a high-concentration one if recommended by a dentist, helps strengthen teeth and remove plaque. Daily flossing and the use of interdental brushes are also important for cleaning around exposed root surfaces and between teeth.
Regular fluoride use is a key part of prevention. In addition to fluoride toothpaste, professional applications of fluoride varnish every 3 to 6 months can significantly reduce the risk of root caries, especially for individuals at higher risk. Dietary modifications, such as reducing sugary and acidic food and drink consumption, limit the fuel for decay-causing bacteria. Chewing sugar-free gum containing xylitol can also help stimulate saliva flow, which aids in neutralizing acids.
Consistent dental check-ups are also important for professional cleanings and early detection of any signs of decay. Managing dry mouth is another preventive measure. Staying hydrated, chewing sugar-free gum or lozenges, and using saliva substitutes can help maintain adequate salivary flow. Avoiding alcohol-containing mouthwashes, which can worsen dryness, is also advisable. Addressing gum recession through professional treatments can also help protect exposed root surfaces from decay.