Transfrenular Single-Incision (TrSI) Flaps: A Modified Minimally Invasive Technique That Optimizes Aesthetic Outcomes in Maxillary Central Incisor Apicoectomy—Technique Description and Case Report

Abstract

Background and Objectives: Achieving optimal soft-tissue aesthetics is a paramount challenge during an apicoectomy of the maxillary central incisors. This article presents a novel modification of the Eskici Vertical Flap, designed to minimize scar formation, preserve the architectural integrity of the sub-mucosal fibers, and eliminate the risk of marginal gingival recession. Methods: The Transfrenular-Single Incision (TrSI) flap is elevated via a precise two-step process. First, a sagittal incision is carried out through the mucosa along the midline of the maxillary labial frenulum. Blunt lateral tunnel preparation is then performed toward the targeted tooth apex, and a subsequent deep periosteal incision with bony contact provides localized access to the periapical lesion. Following Paraendodontic Surgical Intervention (PSI), a two-layer suturing technique is implemented: the deep layer utilizes resorbable sutures to restore periosteal integrity and reposition the basal fibers of the frenular connective tissue, while the superficial layer promotes accurate mucosal edge adaptation. Results: The surgical access provided by the TrSI flap provides clinically sufficient exposure to perform precise osteotomy, retrograde root-end preparation, and biocompatible sealing. The evaluated clinical cases demonstrated optimal healing kinetics, the complete absence of visible scar tissue, and zero marginal gingival recession. Conclusions: The TrSI flap modification constitutes a highly predictable and effective option for PSI in the aesthetically critical anterior maxilla. Although its application spectrum is primarily limited to the central incisors, its capacity to prevent aesthetic deformities warrants its consideration in selected surgical protocols.