The US Army, in conjunction with academics, is developing a chewing gum that will help soldiers maintain oral hygiene while out on manoeuvres, says a report in Nature. In combat situations, soldiers don't have the luxury of being able to brush and floss their teeth. Add to this the impact of the stress, and you end up with a big dental problem. The US military estimates that 15% percent of their soldiers suffer from dental emergencies.

The chewing gum contains a protein called KSL that kills harmful mouth bacteria, such as Streptococcus mutans, by targeting and attacking the cell membrane. After the protein has done its job, it is harmlessly broken down in the stomach by digestive enzymes. The researchers say that the digested protein doesn't interfere with gut microflora.

Patrick DeLuca of the University of Kentucky, who presented the results of the initial tests at the annual meeting of the American Association of Pharmaceutical Scientists in Nashville, Tennessee, said that the gum could be used by anyone who is away from their bathroom for days at a time, including aid workers and music-festival-goers.

Although chewing gum is given to soldiers in their ration packs, it is unlikely that they will see the KSL gum anytime soon. The gum is still at the prototype stage. The researchers estimate that it could be four years before the finished product is available.