OBJECTIVE The aim of this article is to introduce three treatments for patients with gingival fenestration as a result of chronic apical periodontitis. Gingival fenestration is a relatively uncommon soft tissue lesion in which the root apex is exposed in the oral environment after the destruction of the overlying buccal bone plate and mucosa. At present, no clear etiology or treatment guidelines exist for gingival fenestration. This article reports three successfully treated cases of gingival fenestration associated with chronic periapical infection. This report can help contribute to treatment guidelines for gingival fenestration. METHODS All cases were treated with apicoectomy in conjunction with a connective tissue graft (CTG). According to the different conditions of the patients, we used some slightly different treatment methods during the operation. In case 1, we treated gingival fenestration in the mandibular left first premolar by endodontic therapy with root-end resection and retrograde filling and regenerative surgical therapy using a xenograft and CTG. In case 2, we treated gingival fenestration in the maxillary left lateral incisor by endodontic therapy with root-end resection and retrograde filling in vitro and regenerative surgical therapy using advanced platelet-rich fibrin (A-PRF) and CTG. In case 3, we treated gingival fenestration in the mandibular left second premolar by endodontic therapy with root-end resection and retrograde filling and regenerative surgical therapy using CTG. RESULTS Endodontic treatment was combined with periodontal surgery to achieve predictable treatment results. After 13 to 25 months of follow-up, all cases showed that the gingival fenestration had healed well, and the patients had no discomfort. CONCLUSIONS These three cases show the possibility of using apical excision combined with a CTG and/or bone graft/PRF in the treatment of gingival fenestration. Reporting these three cases may help advance the field of treatments for gingival fenestration.