Caries

Caries is tooth decay resulting from acid production by bacteria. Caries extensive enough to expose the pulp can cause sensitivity and pain; advanced caries can cause infection. Caries is detected during dental probing and confirmed by dental x-rays. Treatment is with resins, amalgams, and restorative techniques. Advanced caries may require extraction or root canal therapy.

Geriatric Essentials

• The elderly are more susceptible to caries; contributing factors include inadequate oral hygiene, infrequent dental examinations and cleanings, salivary gland dysfunction, frequent snacking, and removable partial dentures.
• Root surface caries becomes more common in the elderly because of periodontitis, local trauma, alveolar bone loss, exposure of root surfaces by gingival recession and periodontal pocketing, and inadequate removal of food between teeth.
• The elderly experience less tooth sensitivity overall, but symptoms, signs, and diagnostic strategies are otherwise similar to those of adults of other ages.
• Elderly patients with impaired dexterity may benefit from electric toothbrushes or manual toothbrushes with larger handles, and from floss holders.
• Patients with dementia and those with disorders that limit upper extremity mobility and dexterity (eg, stroke, Parkinson's disease) may require toothbrushing by others and professional cleaning more often than every 6 mo.

Caries is decay of tooth structure resulting from acid production by bacteria residing in dental plaque. The elderly are more susceptible to caries because of inadequate oral hygiene, infrequent dental examinations and cleanings, insufficient use of fluoride-containing oral hygiene products, salivary gland dysfunction, frequent snacking, and removable partial dentures, which can trap plaque around teeth and create an environment conducive to caries formation. Gastroesophageal acid reflux is an occasional contributor; the acid erodes tooth structure, leaving a thinner layer of enamel or dentin that is more susceptible to carious bacterial processes.

Adults of all ages develop coronal caries (caries on the crown or enamel surface). The elderly develop coronal caries but are also more susceptible to root surface caries (caries on the root or cemental surface; see Figure 104-1) because of alveolar (supporting) bone loss around the teeth. Alveolar bone loss occurs primarily as a result of periodontitis, although tooth loss and osteoporosis may contribute; it exposes root surfaces to abrasion, erosion, attrition, demineralization, and caries-causing bacteria. Gingival recession and periodontal pocketing also expose root surfaces in the elderly. Inadequate removal of food between teeth also contributes. Once exposed, the root surface of the tooth is more susceptible to dental decay than the chewing or coronal surface, and it is less likely than enamel to benefit from fluoride therapy. Therefore, more careful hygiene is required for these root surfaces.

Symptoms and Signs

Caries is almost always asymptomatic until it becomes extensive and exposes the tooth's neurovascular supply located in the dental pulp, causing sensitivity and pain. The elderly tend to experience less sensitivity and pain with any noxious stimulus because with aging the pulp chamber and root canal recede and become filled with mineralized tissue. However, without treatment, caries progresses and penetrates the dental pulp, causing symptoms and infection that can cause facial and pharyngeal infection, bacteremia, and sepsis.

Caries appears as dark brown to black discolorations on any portion of a tooth (see Photo 104-1). Early lesions tend to be soft; long-standing lesions become hard.

Diagnosis

Caries is detected by dental probing in most cases, and diagnosis is confirmed by dental x-rays (see Photo 104-2). Root surface caries is usually harder to diagnose than coronal caries because evaluation of root surfaces takes more time. More time is needed because gingival recession (see Photo 104-3) exposes difficult-to-view cementum surfaces that become covered by bacterial plaque that is challenging to remove. Additionally, dental x-rays are less accurate for showing root surface caries.

Treatment

Treatment with resins, amalgams, and restorative techniques is usually provided by trained dentists. If caries is advanced, extraction or root canal therapy may be required.

Prevention

Prevention involves measures applicable to all age groups: daily mouth rinsing with antiplaque rinses (or using a water jet oral irrigator) to soften plaque, daily toothbrushing with a fluoride dentifrice (using a soft-bristle manual toothbrush or an electrical toothbrush), and professional prophylaxis every 6 mo.

Toothbrushing becomes more important with aging because the gingivae tend to recede and more plaque accumulates between teeth. Regular and meticulous toothbrushing may still leave plaque between teeth. Therefore, toothbrushing should be supplemented with daily flossing and use of an interproximal brush for cleaning between teeth, especially molars.

Patients with recurrent caries may benefit from prescription-strength fluoride dentifrices (0.4% stannous fluoride or 1.0/1.1% Na fluoride). Elderly patients with impaired dexterity caused by arthritis or other disorders may have difficulty brushing their teeth properly; an electrical toothbrush or a manual toothbrush with a larger handle may be easier to use. These patients may benefit from working with an occupational therapist who can suggest devices with special handles and instruct them on their use. Floss holders may also help.

People with cognitive impairment may need to have their teeth brushed by others, a task that is not easily accomplished. Health care providers and family members responsible for this daily task should be trained by dental professionals on assessment of and appropriate techniques regarding care of the oral tissues. Patients with recurrent caries despite professional prophylaxis every 6 mo and those with diminished dexterity, oral motor or peripheral sensorimotor disorders, or cognitive impairment may need more frequent examinations and cleanings.

This topic was last updated September 2005.