I work for the Kenai National Wildlife Refuge on the Kenai Peninsula, AK.
Our LE Officers and Biologists say it's 50/50 if dogs will help deter bears. Sometimes they can deter bears, and sometimes they can bring them right back to you.

I live alone on Skilak Lake, six miles from my nearest neighbor in a guard station. Last year two mailings occurred within 5 miles of my cabin, this past year only one mauling occurred on the Kenai River about 8 miles from me.
3,000 black and 800 Brown/Griz bears are estimated to live on the Kenai Peninsula.

If I take my dog with my she is on leash. I don't want her bringing a Brown/Griz bear back to me.

Everything I do is solo in heavy bear country.
I backpack, hike, canoe and do solo patrols.
I carry bear spray at all times.