The surgical removal of diseased gingival tissue is:

The surgical removal of diseased gingival tissue is known as gingivectomy. This procedure involves extracting the unhealthy gum tissue that can result from conditions like periodontal disease. By removing the affected tissue, the procedure helps to reduce inflammation, eliminate pockets of infection, and allows for better oral hygiene and health.

In the context of periodontal procedures, gingivectomy is distinct from other surgical techniques. For example, gingivoplasty is a procedure that reshapes the gingiva but does not involve the removal of diseased tissue; rather, it focuses on the aesthetic contouring of healthy tissue. Osteoplasty and osteoectomy are surgical techniques that involve bone, specifically modifying the bone structure—osteoplasty reshapes it, while osteoectomy involves the removal of bone. Neither of these procedures targets the gingival tissue directly, which is why they are not applicable to this particular question.