歯科インプラントの失敗と摘出術：スコーピングレビュー

Dental implants are widely used, yet failures occur and the literature on their etiology and retrieval is discrete. A consolidated map of evidence from the past decade can provide valuable guidance to clinicians and researchers.

To (1) chart biological, mechanical and patient-related factors associated with implant failure (2) catalogue techniques described for implant retrieval/explantation. (3) To illustrate publication trends in the field (1983-2025).

A scoping review was conducted following PRISMA-ScR guidelines. Search strategies based on relevant keywords and MeSH terms were performed across PubMed, Scopus, and Web of Science for studies published from 1983 to June 2025. Two investigators (V. S. and S.R.) independently performed screening of the literature electronically in three databases. Clinical studies, case reports, reviews and guidelines discussing dental implant failure classification, risk factors, and explantation techniques were included in the study.After duplicate removal and title/abstract screening, 388 records were included (human studies reporting on failed endosseous dental implants or explantation techniques). Data were charted in duplicate and synthesised descriptively; no critical appraisal or meta-analysis was performed.

All studies included were published between 1983 and 2025, in English language. An analysis of the included literature demonstrated a progressive rise in publications from 1983 to 2025 with a sharp increase in publications after 2015, reflecting growing clinical and research interest. Observational designs predominated (68%), followed by narrative reviews (20%) and systematic reviews/meta-analyses (8%). These studies highlighted multifactorial causes of implant failure categorized as early (0.5%-5.2%) and late failures (0.5%-7.8%). Early failures were predominantly linked to smoking, uncontrolled diabetes mellitus, poor bone quality, periodontitis, radiotherapy, titanium hypersensitivity, and surgical errors. Late failures were associated with biomechanical overload, peri-implantitis, malpositioning, and systemic medication effects Commonly reported causes of failure included peri-implantitis (≈150 studies), systemic conditions such as diabetes and osteoporosis (≈60), medication exposure (e.g., bisphosphonates, SSRIs; 24), and mechanical or prosthetic factors (≈40). Fourteen studies described implant retrieval techniques: trephine burs (7), reverse-torque devices (3), ultrasonic/piezoelectric methods (2), laser-assisted removal (1), and electrosurgery-induced thermoexplantation (1). Success rates for atraumatic retrieval ranged from 70% to 100%.

This scoping review concluded that dental implant failure remains a complex and multifactorial challenge.Peri-implant disease, systemic health factors, and mechanical overload are the most frequently implicated causes of implant failure. Understanding risk factors and applying evidence-based retrieval strategies enhance clinical outcomes and optimize subsequent rehabilitation options.Trephines are the most commonly reported retrieval method, but newer minimally invasive techniques are gaining interest. Further prospective studies and standardized failure definitions are recommended.