Over 700 dentists and two dental schools in Cork and Dublin are to offer free checks to the public for mouth cancer on 21 September, to help detect more cancers and raise awareness about the condition.
Around 150 people die each year from mouth cancer, yet dentists say it remains a relatively unknown condition.
During the first awareness day last year for mouth, head and neck cancer, 3,000 people queued outside the Cork and Dublin dental schools for the free exam.
Six people were diagnosed with mouth cancer and many cases of pre-cancer were also detected.
As a result, a much bigger campaign is being organised this year by the Irish Dental Association with the support of over 700 dentists.
IDA President Dr Conor McAlister said the free check is painless and takes around five minutes.
He said the biggest problem with mouth cancer is late diagnosis.
The symptoms for the cancer include ulcers that will not heal, white, red or speckled patches, neck lumps or swellings and difficulty swallowing.
Tobacco and excessive alcohol consumption are among the risk factors.