Titanium hypersensitivity in dental implants: A systematic review of updated clinical evidence and diagnostic strategies

Abstract

Purpose: Titanium dental implants are widely regarded as the gold standard for tooth replacement because of their mechanical strength and biocompatibility. However, cases of titanium hypersensitivity have been reported, raising concerns about immune-mediated complications in susceptible patients. This systematic review aimed to provide an updated synthesis of the available clinical evidence on titanium hypersensitivity, including diagnostic methods, and management strategies.

Study selection: A systematic search was conducted in PubMed, Scopus, Web of Science, and EBSCO databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The Population, Exposure, and Outcome (PEO) framework was used to identify primary studies published until July 14, 2025, reporting titanium hypersensitivity related to dental implants, diagnostic modalities, and case outcomes.

Results: Of 1,761 retrieved studies, 9 met the inclusion criteria. These comprised one prospective study and eight case reports involving 21 patients and 33 titanium implants, 20 of which were diagnosed as titanium hypersensitivity cases based on skin testing, immunological assays, histological or immunohistochemical analysis, or clinical symptoms. In 17 cases, implant removal was required, whereas three were managed by abutment replacement.

Conclusions: Despite the limited evidence, current data indicate that titanium hypersensitivity is rare but clinically relevant. Titanium micro-particles often originating from early mechanical wear may act as immunological co-factors in susceptible patients, underscoring the need for standardized and sensitive diagnostic protocols to support early and accurate identification.