Flapless submucosal instrumentation treatment of peri-implantitis: Contemporary evidence and clinical protocol.

BACKGROUND/AIM: Peri-implantitis is a plaque-associated disease characterized by inflammation of the peri-implant mucosa and progressive loss of supporting bone, representing a growing clinical and public health challenge. Conventional nonsurgical therapies often provide limited and unpredictable outcomes, while surgical approaches are associated with increased morbidity and variable long-term success. In this context, minimally invasive strategies, particularly flapless submucosal instrumentation, have emerged as a potential alternative or adjunct in the management of peri-implantitis. The aim of this narrative review is to critically appraise the contemporary evidence on flapless treatment approaches for peri-implantitis. MATERIALS AND METHODS: This narrative review analyzes the available literature on flapless submucosal instrumentation for peri-implantitis, presented as a minimally invasive access approach performed without flap elevation that combines submarginal instrumentation with deliberate peri-implant degranulation/curettage to improve access to the defect and implant surface, and may be considered in treatable, selected peri-implantitis cases within a stepwise care pathway. The biological rationale for flapless therapy is discussed based on the histopathological characteristics of peri-implant lesions, emphasizing the role of inflamed peri-implant soft tissues as a persistent reservoir of infection. Current mechanical, chemical, and adjunctive modalities employed within flapless protocols are reviewed. RESULTS: Clinical, radiographic, systemic, and patient-reported outcomes associated with flapless treatment approaches are examined. In addition, indications, limitations, and prognostic factors-including defect morphology, implant surface characteristics, prosthetic design, and patient-related risk factors-are analyzed. CONCLUSION: Although the available evidence remains heterogeneous and is largely derived from nonrandomized studies, flapless submucosal instrumentation appears to be a biologically sound and minimally invasive option for selected peri-implantitis cases, which may be repeated when clinically indicated while acknowledging heterogeneous protocols and limited comparative evidence. CLINICAL RELEVANCE: Flapless submucosal instrumentation may reduce the need for more extensive surgical interventions. Practical clinical recommendations and step-by-step treatment algorithms are proposed to support evidence-based and patient-centered decision-making in the management of peri-implantitis.