Saliva is your mouth's built-in defence against decay. Heavy drinking can weaken it, but it isn't the only thing going on.
A common clinical finding is that people who drink heavily get more decay. Dry mouth is often named as the reason. The picture is a bit more mixed than that, so here's the fair version.
What Saliva Does
Saliva washes food and bacteria away, neutralises acid after you eat or drink, and supplies the minerals that let early damage in enamel repair itself. When there's less of it, your teeth lose a lot of protection. That's why dry mouth, whatever its cause, raises the risk of decay.
What the Research Shows
A review of alcohol and oral health concluded that excessive drinking raises the risk of decay and gum disease, with reduced saliva flow as one of the routes. Clinical reviews also report that chronic heavy drinking reduces salivary flow and makes saliva more acidic. But the evidence isn't uniform: one controlled study of people with chronic alcohol dependence found lower resting saliva flow and lower saliva pH, yet no more decay than the comparison group. So dry mouth is part of the story, not the whole of it.
What Else Is Going On
Drinks themselves matter. Mixers, alcopops, cider and cocktails carry sugar, and many drinks are acidic, so frequent sipping keeps your teeth under attack. Frequency matters more than quantity. Brushing tends to slip after a night out, and snacking often goes up. Add a drier mouth to that, and decay has an easier run.
Signs of a Dry Mouth
A sticky or dry feeling, constant thirst, trouble swallowing dry food, bad breath, a burning tongue, or new decay near the gum line. Dry mouth is common and has many causes, including a lot of everyday medicines, so it's worth mentioning to us whether or not you drink.
What Helps
Drink water alongside alcohol and sip it through the day. Chewing sugar-free gum stimulates saliva. Brush with fluoride toothpaste last thing at night, and wait a while after acidic drinks before brushing. If you're at higher risk, we may recommend a higher-strength fluoride toothpaste. And cutting down helps your mouth as much as the rest of you. Healing after treatment is another reason to keep an eye on your units.
Sources: RDH magazine, Oral implications of alcohol consumption. The impact of alcohol consumption on the oral health status: review, Romanian Journal of Oral Rehabilitation. Caries prevalence in chronic alcoholics and the relationship to salivary flow rate and pH.