Central defender Mathieu Baudry was shown his second yellow card inside two minutes to leave the home side playing out the final five minutes a man short, but the point was a far reflection of the play.
Defences were well on top in the second half with little to concern either goalkeeper after a lively first 45 minutes when both had been asked some searching questions.
O’s goalkeeper Gary Woods failed to hold a 20th-minute drive from Mark Randall, but immediately redeemed himself when tipping the follow-up effort by Benik Afobe over the crossbar.
Dons keeper David Martin was given his first serious question 10 minutes later when turning a 35-yard shot from full-back Shane Lowry flew over the top.
Martin then denied Shaun Batt with his feet after the O’s striker had been left with a one-on-one chance before going full-stretch to deny a snapshot by Darius Henderson.
After the interval, both teams battled for midfield superiority and often cancelled each other out with little opportunity to break the deadlock.
Jay Simpson went closest for the home side when his shot was deflected for a corner while a powerful free-kick by Dons’ leading striker Afobe cannoned into an Orient defender.
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