A Western Australian dentist whose four practices generate more than 10 per cent of revenues for stricken Smiles Inclusive has raised serious concerns about the level of ''cash burn'' at the ASX-listed group which went into a trading halt on Monday.

Smiles Inclusive operates 56 dentistry practices around Australia, most of which trade under the Totally Smiles banner. The stock went into the halt as it embarked on an emergency capital raising, with its share price sitting at just 6¢.