Saliva is easy to overlook until there is not enough of it. It washes away food debris, neutralises acid, carries calcium and phosphate that repair softened enamel, contains antibacterial proteins, and makes speaking, tasting and swallowing possible.
When flow drops, all of those protections drop with it. Dry mouth is not merely uncomfortable; it is one of the strongest predictors of rapid decay in adults.
What causes it
Medications
By far the most common cause. Several hundred medications reduce saliva, including many antidepressants, antihistamines, blood pressure medications, diuretics, some pain medications and medications for bladder control. Taking several at once compounds the effect. Never stop a prescribed medication over this; raise it with your prescribing doctor, because an alternative or a dose adjustment is sometimes available.
Dehydration
Straightforward and common, particularly with exercise, air conditioning and alcohol.
Mouth breathing
Nasal congestion, hay fever, a deviated septum or habitual mouth breathing dries the mouth, especially overnight. Canberra’s spring pollen season makes this a seasonal pattern for a lot of people. Snoring has the same effect.
Medical conditions and treatment
Diabetes, Sjogren’s syndrome and some autoimmune conditions reduce saliva. Radiotherapy to the head and neck can affect the salivary glands substantially, sometimes lastingly. Where this applies, dental review is usually part of the care plan and should be arranged before treatment starts where possible.
Lifestyle
Alcohol, caffeine, smoking and vaping all contribute. Alcohol-based mouthwashes make dry mouth worse despite the initial sensation of freshness.
Age
Ageing itself has a modest effect. The stronger association is that older adults take more medications.
Why the decay risk rises so sharply
Without adequate saliva, acid produced by plaque is not buffered and sits on the enamel for longer. The calcium and phosphate that normally repair early damage are not delivered. Food debris is not cleared. The result is a characteristic pattern: decay at the gum line and on root surfaces, often on multiple teeth at once, sometimes appearing within months in someone who previously had none.
People with dry mouth also tend to sip sweetened drinks for relief, which accelerates the process considerably. If you take nothing else from this, take that: relieve dryness with water, not with soft drink, juice or sweetened tea.
Other consequences
- Difficulty chewing, swallowing and speaking for long periods.
- A burning or sore sensation, and a sore or cracked tongue.
- Altered taste.
- Bad breath, since bacteria are not being washed away. See persistent bad breath.
- Oral thrush, which is more common when saliva’s antifungal action is reduced.
- Dentures becoming loose and uncomfortable, since saliva contributes to their retention.
- Cracked lips and angular cheilitis at the corners of the mouth.
What helps
- Sip water through the day and keep some by the bed.
- Chew sugar-free gum, particularly one containing xylitol. Chewing is one of the more effective ways to stimulate what flow remains.
- Saliva substitutes, available as sprays, gels and lozenges from a pharmacy. Gels are useful overnight.
- High-fluoride toothpaste. Your dentist can prescribe a higher concentration than standard, which makes a material difference to decay risk. Spit, do not rinse.
- Alcohol-free mouthwash only.
- Reduce caffeine and alcohol, and stop smoking or vaping.
- Humidify the bedroom and address nasal congestion so you are not mouth breathing overnight.
- More frequent check-ups. Three to four monthly rather than six monthly is common for people with significant dry mouth, because catching decay early is the whole game.
- Avoid sugary and acidic drinks entirely as a means of relief.
Tell your dentist what you take
A current medication list changes how your risk is assessed and how often you are seen. It also lets the dentist recognise a pattern of decay as medication-related rather than as a change in your habits, which is both more accurate and a good deal fairer.
What it costs
Our new patient consultation and clean package starts from $219 and includes an examination, scale and clean, fluoride treatment and two bitewing X-rays. Where decay has developed, tooth-coloured fillings range from $209 to $450 and porcelain crowns start from $1,800. More frequent recall visits are quoted individually. Current fees are on our price list, with more on cleans and check-ups at our Canberra practice.
Common questions
Should I stop the medication causing it?
Not on your own. Raise it with your prescribing doctor, who can consider alternatives. Meanwhile the measures above reduce the risk.
Is dry mouth just part of getting older?
Not inherently. Medication use is the stronger factor, and it is usually manageable.
Do saliva substitutes work?
They relieve symptoms and make eating and speaking easier. They do not replace saliva’s protective functions, so the fluoride and recall measures still matter.
Is sugar-free gum safe for my teeth?
Yes, and chewing it after meals is actively beneficial because it stimulates saliva flow.
Booking an appointment in Canberra City
Civic Gentle Dental Care is a dentist in Canberra at Suite 8, Level 3/161 London Circuit, Canberra City, a short walk from the Canberra Centre. To arrange an appointment, call (02) 6247 0224 or send us a message through our contact page.
This article is general information only and is not a substitute for individual dental advice. Whether a treatment is suitable for you, and what it will involve, can only be determined after an examination by a dentist. Any prices mentioned are estimates drawn from our current price guide and are not a quote.