This comes up over and over on other forums, so I thought we better put it here.
Sugar gliders do NOT get Lumpy Jaw. Lumpy Jaw is caused by a very specific bacteria and is common to some species, but not to sugar gliders.
If you glider has a lump on its head/face, chances are the glider has an abscess. Abscesses are very common in sugar gliders and are currently being studied by the SUGAR Group. If you find your glider with an abscess, please review the information provided in this forum, get your glider to the vet, and participate in the SUGAR Group's research.