Is there is anything in your yard to attract the bear again. Bird feeders? Dog food?? Grease in a grill??? Compost pile???? If there are any of these, the bear may be back.
Bears are constantly looking for food and once they find a source, they keep coming back for more. If your yard is "clean", it shouldn't be back, especially since your dog chased it away. It is probably a young male looking for a new home, and since all the good spots in the wild are taken by older bears, he is cruising the neighborhood.
Here are some pictures from my old stomping grounds for your viewing pleasure.
http://www.adn.com/2011/05/05/1847113/2011-bear-sightings.html