Periodontal knives also known as gingivectomy knives, primarily used for gingivectomy and gingivoplasty. Gingivectomy is a surgical periodontal procedure in removing or reshaping gums. A gingivectomy may be done to get rid of diseased gum tissue or pockets between the teeth and gums if it cannot be cured with antibiotics or root planning and scaling. Gingivectomy is usually done before gum disease has damaged the bone supporting your teeth.