How to keep your teeth as you age and why having 20 teeth at 80 matters

For someone with a morbid dread of going to the doctor, I am surprisingly sanguine when it comes to the dentist. It wasn’t always this way, and my change of heart has to do with, well, strawberries.

For the first half of my life, I was dental-phobic. The terror took root when I was eight. A badly decayed baby tooth needed to be extracted, and halfway through the procedure, a jolt of pain sent me jumping out of the chair. I refused to let the dentist finish.

That fear lingered well into adulthood. In my late 20s, I had my wisdom teeth removed under general anaesthesia. The procedure went smoothly enough, but what happened after was a nightmare.

An abscess developed in my gum. I can still see the metallic glint of the syringe, its needle bent at an alarming angle, being inserted into my mouth. The pain as it pierced my inflamed gum and sucked the pus out was excruciating.

Understandably, I was not a fan of dentists.

Everything changed in my 30s when a friend recommended her dentist. I wanted to swap dark fillings with tooth-coloured ones in two molars. I arrived at the clinic bracing myself for the worst. But before doing anything else, Dr Ong applied a numbing gel to my gums.

It tasted distinctly of strawberry and changed my life.

The taste was so pleasant, and Dr Ong was gentle and reassuring. For the first time in my life, I walked out of a dentist’s office thinking: That wasn’t so bad. I have not dreaded visits to the dentist since.

Today, my dental battles are more about the ravages of time. With age, my gums have receded. Combined with years of aggressive over-brushing, I have pockets of sensitive root surfaces that require regular patching.

Tiny, pesky gaps have also opened up between my teeth, creating perfect traps for plaque, bacteria and food debris, which can lead to cavities.

AT LEAST 20 GOOD TEETH AT AGE 80

There is growing evidence that the number and condition of our teeth affect how well we age.

“Good oral health is often linked to better overall health, nutrition and quality of life, which can help people stay active and independent as they age,” says Yang Jingrong, a senior consultant at the periodontics unit, department of restorative dentistry, at the National Dental Centre Singapore (NDCS).

A complete set of adult teeth consists of 32 permanent teeth: eight incisors, four canines, eight premolars and 12 molars, including four wisdom teeth. A 2024 parliamentary reply by the Ministry of Health noted that about 13 per cent of Singaporeans aged over 60 have lost all their teeth.

Yang says retaining at least 20 natural teeth at age 80 is one of the most cost-effective investments you can make in healthy ageing.

A study led by NDCS in collaboration with Duke-NUS Medical School, published in 2026, found that older adults who kept more of their natural teeth tended to stay independent for longer.

For example, those aged 60 to 80 who had 20 to 32 natural teeth and who did not need dentures generally had more years without difficulties in daily activities such as eating, dressing and moving around.

A 60-year-old with 20 to 32 natural teeth may enjoy more than five additional years of independent living and more than three extra years without physical limitations.

With fewer teeth, chewing becomes more difficult. Chewing disability is associated with a 43 per cent higher likelihood of cognitive impairment. At age 60, those with good chewing ability had an estimated 18 years of independent living, compared with 15.1 years for those with impaired chewing. Dentures help only when they truly restore chewing ability, Yang says.

The idea of having at least 20 teeth was introduced by Dutch professor of prosthodontics A.F. Kayser in 1981.

He proposed that people could maintain adequate function with a shortened dental arch, specifically 10 upper teeth working against 10 lower teeth.

The concept was adopted in Japan’s 8020 campaign, launched in 1989 to encourage people to have at least 20 functional teeth at age 80. At the time, only around 11 per cent of Japanese aged 80 had 20 or more natural teeth. Over the past three decades, this has risen to about 52 per cent, says Yang.

Inspired by Japan’s campaign, NDCS rolled out its Oral Health Movement 8020 in 2021 to encourage Singaporeans to retain at least 20 teeth at age 80 through public education and community programmes.

But the number alone is not the point.

Sophia Yee, a consultant at the dental surgery department at Khoo Teck Puat Hospital (KTPH), says the quality, condition and distribution of the remaining teeth matter just as much.

“Having 20 teeth all on the upper or lower jaw alone would not be considered functional,” she says.

Teeth are functional when there is a pair biting against each other, one in the upper jaw and one in the lower. The front teeth, or incisors and canines, are important for tearing food, as well as speech and appearance. The back teeth, or premolars and molars, grind food into smaller pieces.

The condition of those teeth matters too. Loose or painful teeth, or teeth affected by advanced gum disease or decay, may contribute little to chewing function regardless of how many remain.

People who struggle to chew may avoid nutrient-dense foods such as fruits, vegetables and protein-rich foods. Over time, inadequate nutrition can contribute to muscle loss, weakness and frailty.

Maintaining natural teeth also helps keep the muscles involved in chewing active and the bite force strong, says Tan Mei Na, head and consultant, dental services, at Alexandra Hospital.

This becomes particularly important as people age, when conditions such as stroke and sarcopenia, or age-related progressive loss of muscle mass, strength and function, can reduce bite force and chewing ability.

Yee also points out how tooth loss can affect speech and appearance. This can undermine confidence and make some people less willing to socialise, hastening physical and cognitive decline.

WHAT CHANGES WHEN WE AGE

As we move into our 50s and beyond, changes occur not only in the teeth but also in the gums, jawbone and saliva production, says NDCS’ Yang.

The teeth themselves undergo gradual wear from decades of chewing and grinding, as well as exposure to acidic foods and drinks.

Enamel, the hard outer layer of the tooth, can become thinner, allowing the naturally darker dentine underneath to show through.

“This is why teeth often appear more yellow as we age,” Yang says.

Years of repeated chewing forces can also make teeth more brittle and prone to cracks.

The gums may recede, exposing more of the tooth root. The root of the tooth does not have an enamel coating. Instead, it is covered by a thin layer of cementum, which is a softer material more vulnerable to decay.

Older adults may therefore be more susceptible to decay on exposed roots, particularly if oral hygiene becomes harder to maintain or saliva flow is reduced.

Saliva is, in fact, one of the mouth’s natural defences. It helps to neutralise acids, wash away food debris and protect against tooth decay.

The jawbone can also change.

Just as bone density can decrease elsewhere in the body, the jaws can experience gradual bone loss, particularly when some teeth are missing.

Yang says teeth stimulate the surrounding bone during chewing. When a tooth is lost, the underlying bone no longer receives this stimulation and begins to shrink over time. This can affect facial appearance, how dentures fit and future treatment options.

But not every change in an ageing mouth is cause for alarm.

The gradual wear and tear on your teeth, a more yellow appearance, mild gum recession and some degree of dry mouth can occur with age. Existing dental work, such as fillings and crowns, may also need to be maintained or replaced after years of use.

What should not simply be dismissed as part of getting older are gums that bleed when brushing or flossing, loose teeth, or severe or persistent pain that disrupts eating or sleep.

These can signal gum disease, tooth decay, a cracked tooth or infection, and warrant a visit to the dentist, says Yang.

WHEN HEALTH GETS IN THE WAY

Age itself is not the only factor that can affect dental health.

Certain medical conditions, chronic illnesses and medications can make it harder to maintain a healthy mouth.

Certain autoimmune conditions can cause dry mouth, as can medications such as those for high blood pressure and depression.

Persistently reduced saliva can increase the risk of tooth decay and oral infections, and make speaking, chewing and swallowing more difficult.

Dental health can also suffer when people become less able to care for themselves.

Those with dementia, Parkinson’s disease or disabilities following a stroke may find it hard to brush and floss properly.

People with dementia may become resistant to dental care as their condition progresses, says Alexandra Hospital’s Tan.

Yee from KTPH points out that diabetes and gum disease are closely linked. Poorly controlled diabetes can increase the risk of infection and inflammation, worsening gum disease.

Conversely, severe gum disease can cause inflammation and make it harder to control blood sugar.

People with heart disease or high blood pressure may take blood-thinning medications, which can prolong bleeding during procedures such as tooth extractions.

Those with osteoporosis may take medications such as bisphosphonates or denosumab.

These drugs are effective in reducing fracture risk but are associated with a rare complication known as medication-related osteonecrosis of the jaw, particularly after tooth extractions or other invasive procedures, says Yee.

It is important to have a dental check-up to address any dental problems before starting these medications. Patients should also tell their dentist if they are on these drugs.

HABITS TO ADOPT

So, what trips teeth up?

Dentists say ageing itself doesn’t ruin your teeth.

“Many people assume that tooth loss is a normal part of ageing, but healthy teeth can last a lifetime,” says Yang.

Rather, habits accumulated over the years take a toll.

Dentists point to familiar culprits:

• Poor oral hygiene

• Frequent consumption of sugary foods and drinks

• Smoking

Genetics can play a role, influencing factors such as the quality of tooth enamel, composition of saliva and the body's response to oral bacteria.

But, says Yee, genes alone rarely determine whether someone develops oral disease.

The good news is that most age-related dental problems are largely preventable.

Tan from Alexandra Hospital recommends brushing twice a day with fluoride toothpaste and cleaning between the teeth with floss or an interdental brush, where a toothbrush cannot reach.

Both manual and electric toothbrushes can work well when used properly, although an electric toothbrush may be easier for older people with limited hand dexterity, or for caregivers helping someone with their oral care, she says.

But don’t overdo the brushing.

KTPH’s Yee says brushing too aggressively can contribute to tooth wear and gum recession over time. She recommends a soft-bristled toothbrush angled at 45 degrees towards the gum line, with short, gentle back-and-forth strokes to remove plaque beneath the gum edge.

“Avoid medium or hard bristle toothbrushes as they will wear down teeth over time. I often tell my patients to use those only for cleaning household appliances, not their teeth,” she adds.

Timing matters, too.

She says it is best to avoid brushing immediately after a meal as the mouth can be acidic. Brushing at this point can accelerate the wearing down of teeth. Instead, wait about 30 minutes to allow saliva to neutralise the acids first.

Diet is another important factor.

Frequent consumption of sugary foods and drinks provides fuel for oral bacteria, which produce acids that demineralise tooth structure and lead to tooth decay, says Yee.

“It is often the frequency of sugar consumption throughout the day, rather than the total amount consumed, that increases risk,” she adds.

Yee advises drinking plain water after meals and snacks, and after taking medications.

“Seniors taking multiple medications may have dry mouth, and it is important to keep your mouth moist by sipping water frequently.”

And treat your teeth as teeth, not tools.

“Do not use them to open bottle caps, tear things apart, or crack open crab shells,” says Yee.

Teeth accumulate years of wear from daily chewing and can fracture more easily under the wrong kind of pressure.

And if you smoke, quit because smoking increases the risk of gum disease, tooth loss and oral cancer, says Yee.

If a tooth is damaged, treatment depends on how much of the tooth remains healthy.

Teeth with deep cavities involving the nerve can still be saved with root canal treatment, says Tan, while structurally compromised teeth may need crowns to help prevent further fractures.

But if the tooth is too damaged and these treatments may not work reliably, removing the tooth may be the better option.

Missing teeth can then be replaced with:

• Dentures

• Bridges

• Dental implants

Teeth with gum disease can be retained and kept for a long time when treated early, say dentists.

Treatment involves thoroughly cleaning the root surfaces to remove plaque and calculus, or hardened dental stone, which serve as breeding grounds for bacteria.

Dentists emphasise regular check-ups, even when nothing hurts.

“I know this sounds like boring advice, but tooth decay does not cause pain in the early stages, and early gum disease may not present with obvious signs,” says Yee.

By the time pain or other symptoms appear, the problem may already require more extensive treatment.

For those who dread the dentist, routine check-ups may feel unnecessary when their teeth seem fine. But catching problems early can help prevent a tooth from being lost.

And with only 32 to begin with, every one counts.