Following victories over Ulster and the Scarlets, Zebre who secured their first ever win with a shock triumph over Cardiff Blues earlier this month, presented a proverbial banana skin.
But the Dragons cruised to victory with Amos’ double and an effort from Richie Rees, as they maintained their 100 per cent start to the season at Rodney Parade.
Zebre made a commanding start but got little reward for their early enterprise and Jason Tovey fired the Dragons into the lead with a pair of quick-fire penalties.
He kept the scoreboard ticking with the boot and an arcing Adam Hughes burst should have led to a try only for a wayward pass.
The Men of Gwent took a major stride towards victory when Netani Telai pounced to release Amos for an opportunist try following a Zebre mix-up at a five-metre scrum.
Tovey maintained his 100 per cent strike rate with the boot to bring the scores to 16-0 at half-time.
And they sealed the victory within 10 minutes of the restart when Amos grabbed his second try.
An outstanding break from Toby Faletau laid the foundations and he timed his pass perfectly to Ross Wardle, who fed the Wales Under 20 star.
Zebre responded with a Leonardo Sarto try following a sublime Brendon Leonard chip, which Orquera converted.
But the Dragons ended any hope of an Italian comeback when Rees burrowed over from a dominant scrum.
They pushed in the dying stages but were unable to cap their 100th win at Rodney Parade with a try-scoring bonus-point.
