C

A sufficient width of attached gingiva is critical when planning and executing a periodontal flap; it determines how far the flap can be reflected or repositioned without crossing the mucogingival junction and helps ensure postoperative stability and resistance to recession. Surgical techniques such as the apically repositioned flap are specifically modified to preserve or augment attached gingiva because of its importance in healing and long-term maintenance [Carnio & Miller, 1999, PMID 10505814; Oh, 2009, PMID 19903619].