I would treat it as if nothing had happened, just maybe trim it at the top if the break left it jagged.... the breaking shouldn't be much different than taking a cutting. Who knows, it may even produce a couple of branches at the break like my small indoor tree did after I took a cutting a few months ago. If the temps are warm enough, water well once and let it dry out before watering again. Good luck!

Hey chellflower: Thanks for the response. One more question, if the weather is warm enough, should I take it outside and set it in full sun? Before then, should I have it on a heat mat? Thanks in advance!

Be careful with water. Water just enough to keep the roots from drying out. Without leaves, the plant doesn't need much water. Dormancy is related to daylight hours as much (or more) than temps. The heat mat helps, but sunlight (or grow lights) are important. So let the plant have as much daylight as possible. Watch for small bumps on old leaf scars, as these will be the new branches on the bottom portion of the SP. Sometimes it takes a while for them to appear. I had a Mardi Gras that lost its top in the wind, and it took several months for new branches to appear. Then I got about 16 branches all over it. I cut off all but 4 and have a nicely shaped tree developing.
Mike