Aging affects many parts of the body—including the mouth.
Over time, the environment inside the mouth changes. Saliva production may decrease, gums can gradually recede and decades of chewing, brushing and exposure to acidic foods slowly wear down tooth enamel.
These changes are completely normal. But they can make teeth and gums more vulnerable to cavities, gum disease and tooth loss later in life.
The encouraging news is that many of the factors that influence oral health (including daily habits and preventive care) remain highly within our control.
And as scientists learn more about how the mouth changes with age, research is also revealing just how closely oral health may be connected to overall health, including brain health.
Several natural changes can occur in the mouth over time.
Reduced saliva and dry mouth
Saliva plays an important role in protecting teeth. It helps wash away bacteria and neutralise acids that can damage enamel. As we age (and particularly when taking certain medications) saliva production may decrease. Many commonly prescribed medications, including those for blood pressure, allergies and depression, can reduce saliva flow. This can increase the risk of dry mouth and cavities.
Gum recession
Gums may slowly recede over time, exposing the root surfaces of teeth. These areas are more vulnerable to decay because they are not protected by enamel.
Changes in the oral microbiome
The mouth is home to hundreds of different species of bacteria. Most are harmless and exist in balance with the body, but when that balance shifts it can lead to gum inflammation and periodontal disease. Because of these changes, maintaining good oral hygiene becomes even more important as we age.
In recent years, researchers have begun exploring whether oral health could play a role in conditions beyond the mouth, including Alzheimer’s disease.
At the University of Melbourne, scientists have been investigating a bacterium commonly associated with gum disease called Porphyromonas gingivalis. In laboratory studies, repeated exposure to this bacterium has been shown to trigger brain inflammation and biological changes similar to those seen in Alzheimer’s disease in animal models.
Interestingly, researchers do not always find whole bacteria in the brain. Instead, attention has turned to tiny particles released by these bacteria, which can carry molecules that trigger inflammatory responses in the body.
Researchers in New Zealand have also examined the wider relationship between oral health and dementia. Studies from the University of Otago suggest that tooth loss and poor oral health may be associated with dementia risk, although the relationship is complex and influenced by many factors including lifelong health behaviours and access to dental care.
At this stage, scientists cannot say that gum disease causes Alzheimer’s disease. Dementia is a complex condition influenced by many factors including genetics, age, cardiovascular health and lifestyle. However, one theory researchers are exploring is the role of chronic inflammation in neurodegenerative diseases. Because gum disease is a long-term inflammatory condition, scientists are investigating whether it could be one of several contributing factors. What this research reinforces is something dentistry has long recognised: Maintaining good oral health is an important part of healthy aging.
Daily oral hygiene plays an important role in controlling the plaque and bacteria that can lead to gum disease.
Two tools can be particularly helpful as we age:
Electric toothbrushes: These can make brushing easier and more effective, particularly if grip strength or dexterity changes over time. Many models also include timers and pressure sensors that help ensure teeth are brushed thoroughly without damaging the gums.
Interdental brushes: These small brushes are designed to clean the spaces between teeth where a toothbrush cannot reach. As gums recede slightly with age, these spaces often become easier places for plaque to accumulate, making interdental cleaning especially important.
Because gum disease often begins between the teeth and along the gum line, cleaning these areas daily can make a significant difference in long-term oral health.
