What are the positives of gingivectomy?

A Smile: One big positive in exposing more tooth and revealing a much better smile.

Why Gingivectomy?: Gingivectomies are needed for one of two reasons: (1) to remove diseased gum tissue, or, (2) to increase the length of the teeth by the removal of gum tissue that has grown over the "necks" of teeth". If you feel like you have a "gummy smile", then a gingivectomy will allow more tooth structure to be exposed, thereby eliminating a gummy smile.

Healthier gums IF...: If this is right for your situation, it will likely result in healthier gums. Consult with your dentist about both the long-term and short-term implications in your specific situation as well as anything you can do to improve your brushing/flossing technique. Most times "tweaking" you home hygiene will both improve the result and make it last longer.