"Teacher" would be uncommon in this case.
For disciplines originating in the Far East,
we westerners usually address an instructor in
one of two ways:
A) with the title in the original language,
in this case "Laoshi", or
B) with the title "Master".


The Chinese title "Laoshi" would (most often, not always)
come after "Bo", as per custom in original language.
The English title "Master" would precede the family
name "Bo".
So "Bo Laoshi" or "Master Bo".

Just for an example, for karate instructors in America,
even when the instructor is a blue-eyed American who
has never visited Japan, the instructor is addressed as "Sensei".


In following example, both titles are used, with the title "Master"
reserved for the highest standing.
"Laoshi Michael Coulon is the Center Director of the New Hampshire Yang Chengfu Tai Chi Chuan Center..."
"...and has trained with Masters Yang Zhenduo and Yang Jun since 1998."
http://www.nhtaichi.com/index.htm

Here are some more examples with "Laoshi":
http://ezine.kungfumagazine.com/forum/member.php?u=7017
http://www.fas.harvard.edu/~clp/China/partyba.htm

So "Bo Laoshi", with no translation, would be best.
(You may want to include a footnote explaining that
"Laoshi" means "master or instructor", if you think the
reader does not know the term loashi. But if this is for
people already familiar with Tai Chi, then they probably
do know "laoshi".)