The 33-year-old signed a deal with the League One side until the end of the season on Thursday after being released by Premier League outfit Sunderland in May.
And the former Napoli and Sunderland defender, who 10 Italy caps, can’t wait to get started with his new club.
“I am happy to be here because I find some people that believe in me so I can show what I can do for the team,” Dossena told Orient’s website.
“It is important to continue playing.”
Dossena joined Rafael Benitez’s Liverpool side in a £7m deal in 2008 but struggled to make an impact at Anfield.
Despite becoming accustomed to playing football at the top level, Dossena is more than happy to get back on the pitch in England’s third tier.
“It is a different [challenge]. Football is in every part of the world: you have to put the ball in the goal,” Dossena added.
“I know it is a lot different but I am so excited to play one game that it isn’t important if it is League One, Championship or Premier League.”
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