Ms Dorrian, 25, was last seen at a party at a caravan site in Ballyhalbert in 2005.
The PSNI said no human remains were found during the search, which started a week ago, but a number of items were removed for further examination.
Police have previously made several arrests, but no-one has been charged with her murder.
Det Ch Insp Justyn Galloway said: "Our inquiries are continuing. We would again appeal to those individuals who know what happened to Lisa to provide that information.
"This would enable Lisa's family to have some degree of closure as they face another anniversary of her disappearance in the coming days without the answers they so desperately crave and deserve."
Last February, a reward of up to Â£5,000 was offered by the Crimestoppers charity for information about Ms Dorrian's murder.
This reward was in addition to one of Â£10,000 previously put up by the family.
Police investigating the murder of County Down woman Lisa Dorrian have ended a search of land outside Comber.