Ailing dentistry group Smiles Inclusive says there are 200,000 patients across its 82 locations who haven't returned in the past 18 months, and enticing them back for an appointment is one of the central elements of a turnaround plan.

The company, which is attempting to raise up to $3.3 million in a 1-for-1 rights issue, also revealed its auditor KPMG expects asset impairments to rise by a further $11.1 million for 2018-19, on top of the originally announced $13.7 million.