Patients with liver disease may be able to avoid an early death simply by brushing their teeth properly.
Inflamed gums caused by poor oral hygiene can harbour bacteria, which then travel to the liver and may cause death in diseased patients.
Liver disease is the fifth biggest cause of death in England and Wales.
The condition claimed over 11,000 lives in the UK in 2014.
Past research suggests gum disease is linked to liver disease progression and poor outcomes in patients who have had a transplant.
Good oral hygiene could prevent early death in patients with irreversible liver scarring
There are more than 100 types of liver disease.
Around two million Britons are affected by a form of the disorder.
The main causes are:
Symptoms are rare until the disease is advanced.
It may then cause weight loss, reduced appetite and jaundice.
Medication is available, however, a transplant may be necessary in severe cases.
Source: NHS Choices
Scientists from Aarhus University Hospital, Denmark, analysed 184 cirrhosis patients, of which 44 per cent had severe gum disease.
Cirrhosis is irreversible scarring of the liver, which can cause permanent damage.
Around half of the study participants died within a year.
An analysis revealed severe gum disease was correlated with cirrhosis complications.
Lead author Dr Lea Ladegaard Gronkjaer, said: 'Our study showed severe periodontitis strongly predicted higher mortality in cirrhosis.
'Periodontitis may act as a persistent source of oral bacterial translocation, causing inflammation and increasing cirrhosis complications.'
Periodontitis is the scientific term for gum disease.
Although the study's results are encouraging, some experts warn further investigation is needed to determine the possible effects of improved oral hygiene in liver disease patients.
Professor Philip Newsome, liver specialist, the University of Birmingham, said: 'This study demonstrates the association between gum disease and risk of death in patients with liver disease - further studies are now required to determine if improving gum care can improve outcomes in patients with liver cirrhosis.'