How safe is it to lance a gum abscess by yourself?

No: You can cause more damage to yourself.

Not recommended: Trying to lance the abscess can drive the infection deeper with the risk of the infection spreading into the blood stream and beyond. If you can't get into a dentist, get to emergency room.

Treat the cause: Treat the cause, not the signs and symptoms. Lance a gum abscess by yourselft is only treating the symptom, not the cause. The dentist should diagnose the cause whether it is an endo abcess (tooth nerve) or perio abscess (gum tissue). Root canal would be the treatment for endo abscess. Perio debridement is the treatment for perio abscess. Antibiotic given. Occlusion must be addressed.