It is too early to claim victory in the gum wars. After all, one side - Wrigley - began with a mouthwatering 98% share at the beginning of 2007. But to say Cadbury Trebor Basset is cock-a-hoop about Trident would not be an understatement.

Since Trident's launch in January, the upstart has grabbed a 12% share of the £241m UK gum market - some £30m - making it one of the fastest-growing food brands in recent history. Sales in this 'gum revolution' - as Cadbury marketers have dubbed it - have exceeded even its expectations.

"We never reveal our projections, but we are delighted," says Tony Bilsborough, head of external communications at CTB.

In any battle it is not uncommon for one side to claim early victory, but should Wrigley regard the newcomer as a true threat? Trident entered with innovative flavours, such as vanilla and mint and strawberry and lime, and its strong early sales will undoubtedly have rattled Wrigley. Last year sales of Wrigley's Orbit brand fell 24%, Airwaves fell 4% and its standard gum plummeted almost 8%. Sales of its leading brand Wrigley's Extra, meanwhile, were stagnant.

A change in Wrigley's tactics in recent months indicate the company is taking Trident seriously. Until now the company has steadfastly followed the breath-freshening path, but its recent moves appear to be more than just a passing nod to Trident, by targeting habitual chewers rather than those who chew gum for breath-freshening properties. Rather than leading the market, Wrigley for the first time appears to be following it.

In February it extended its Orbit brand with two new flavours - Mint Mojito and Raspberry Mint - and last month it added Strawberry and Watermelon flavours to its Extra brand. It is also axing its innovative Extra Thin Ice breath strips after five years on shelf. Yet Wrigley, untroubled by Trident's entry, could be looking favourably at the newcomer. Since Cadbury's assault began, sales in the UK gum market as a whole have increased 19% [Nielsen]. Even though Wrigley has lost market share, its sales have received a kickstart. Sales of Orbit, for example, rose 5.7% in the latest four weeks.

"Wrigley has not lost anything. In fact it has benefited from the launch," says Nielsen's Danielle Tolson. "Trident has reinvigorated a category that previously had fallen 4% over the past two years."

Wrigley shares her optimism. "We look for Cadbury's entry to create news and excitement in the category," says communications manager Alex MacHutchon. "Fair and open competition is the guarantor of a healthy marketplace and will ultimately benefit all sides."

But directors won't be sleeping easy yet. The £10m budget Cadbury is spending on Trident will turn the screws on Wrigley, says John Noble director at British Brands Group, who believes that, in time, Trident could pose a bigger threat.

"Dyson managed it with Hoover," he says. "If a market is tired there is always room for a new brand to come in and shake things up. The first thing the established brand will do is to go back and assess how it stands in the market against the new competitor."

There is little doubt Cadbury has the top position in UK gum in its sights. Globally, Trident grew sales by more than 20% last year. It leads in 18 out of the top 50 gum markets and Cadbury believes the UK could be number 19. "There is a long way to go but we are used to taking on Wrigley and competing successfully toe-to-toe in many markets worldwide," says Bilsborough.

With an 85% share in the UK ­Wrigley won't be pressing the panic button yet. But it clearly has something to chew on.