Peace begins with a smile and offering one is free therapy, so the sayings go.

However research reveals Australians might be feeling a little apprehensive about flashing a mask-less grin now that COVID-19 restrictions have eased.

Commissioned by the Extra Oral Healthcare Program for World Oral Health Day, a national survey suggests more than two thirds of adults aren't confident with their smile.

Of those, 27 per cent say yellowy teeth are behind their reluctance, while 21 per cent cite bad breath or oral health.

Nearly one in five of those polled said they try to avoid smiling too much in front of people they don't know, and 15 per cent worry they might be judged for not having a perfect smile.

The survey also delves into the impact of a smile during social interactions, the ingredients for a confident smile, and steps Aussies would be prepared to take to improve their smile confidence.

Some 53 per cent of respondents said they smile to show they're friendly and two in five to be polite.

Not everyone, though, is a worthy recipient.

One in two reckoned they would deliberately withhold a smile in a social situation, and a third agreed they might issue a false grin to a stranger.

Fake smiles were least likely directed at partners (three per cent) and family (five per cent).

While the research suggested 56 per cent of Australians consider healthy teeth and gums important when it comes to confidence in their smile, the pandemic has impacted how often they visit the dentist.

Nearly a third of respondents said the pandemic had interrupted their regular attendance and almost half admitted not visiting a dentist at all last year.

"With lockdowns behind us, we look forward to seeing patients go back to a more regular visiting schedule," said Gold Coast dentist Matt Hedge.

"In the meantime, we recommend Aussies brush and floss their teeth twice a day as the first step to maintaining good oral health.

"And as we're now on-the-go again, chewing sugar-free gum after meals and drinking water are both great ways to wash away food debris, breakdown plaque, keep breath fresh and boost confidence in your smile."

More drastically, 35 per cent of the research participants say they would consider a teeth whitening kit and 29 per cent visiting a cosmetic dentist for teeth whitening.