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An apically repositioned (apically displaced) flap is designed to move the gingival margin apically, thereby eliminating the periodontal pocket while simultaneously preserving/increasing attached gingiva and exposing more clinical crown. Clinical trials show it provides the greatest pocket-depth reduction among periodontal surgeries, classifying it as a pocket-elimination procedure [Zamet, 1975, PMID 1094036; Tuan, 2000, PMID 11203584].