New Study: Implant-Derived Titanium Particles May Affect Antimicrobial Treatment Outcomes for Peri-implantitis

Source: "Implant-derived titanium particles impair macrophage bacterial clearance via TRPC1 and lysosomal dysfunction"

DentalGoodNews｜In April 2026, an in vitro and animal model experimental study published in "PNAS Nexus" showed that titanium particles released from dental implants during inflammation, maintenance procedures, or mechanical abrasion are taken up by macrophages. This may reduce the phagocytic and clearance ability of macrophages against bacteria by affecting TRPC1-related calcium ion signaling and lysosomal function. This finding may provide a new biological explanation for the frequent clinical failure of antibiotic treatment for peri-implantitis (PI), and suggests the potential of the TRPC1 channel as a drug target for PI treatment.

Researchers pointed out that peri-implantitis is typically associated with bacterial biofilms, but clinically, some cases continue to progress even after antimicrobial treatment. Based on this, Professor Georgios Kotsakis' team at the Rutgers School of Dental Medicine believes that tiny titanium particles (i-TiPs) released from implants may be a persistent non-microbial pathogenic co-factor. These particles are released in inflammatory environments or due to improper use of metal scaling instruments during clinical maintenance, and are easily captured by immune cells.

The study results showed that titanium particles from dental implants can be released in inflammatory environments, during clinical maintenance procedures, or when the implant surface undergoes mechanical abrasion, and accumulate in peri-implant tissues. In experiments, researchers observed that these particles are taken up by macrophages and are associated with increased TRPC1-mediated calcium ion influx, decreased lysosomal acidification capacity, and altered lysosomal function.

Source: "Implant-derived titanium particles impair macrophage bacterial clearance via TRPC1 and lysosomal dysfunction"

Lysosomes are key sites for immune cells to degrade captured bacteria. Impaired acidification may directly lead to a significant reduction in the clearance efficiency of macrophages after phagocytosing bacteria. The results showed that under titanium particle exposure, the phagocytosis ratio of macrophages to bacterial particles was lower than that of the control group. For example, in the E. coli bioparticle experiment, approximately 45.44% of cells in the control group showed phagocytic signals, while the titanium particle-treated group showed about 22.24%; under conditions of LPS pretreatment followed by titanium particle exposure, this ratio was approximately 14.57%.

In addition to decreased phagocytic capacity, researchers also observed that macrophages exposed to titanium particles released pro-inflammatory cytokines such as IL-1β, IL-6, and TNF-α. Therefore, researchers believe that this state of maintaining an inflammatory response while reducing bacterial clearance ability may be related to the persistent and refractory nature of peri-implantitis.

Source: "Implant-derived titanium particles impair macrophage bacterial clearance via TRPC1 and lysosomal dysfunction"

In the animal experiment section, the research team validated findings using TRPC1 gene knockout mice. Under conditions of combined titanium particle and bacterial stimulation, TRPC1-deficient mice showed lower levels of pro-inflammatory cytokines, and the titanium particle-related abscess areas were smaller than those in wild-type mice. Researchers suggest this may indicate that TRPC1 is involved in the inflammatory response and immune function changes induced by titanium particles.

Currently, the research team is screening candidate drugs targeting the TRPC1 signaling pathway under funding from the National Institutes of Health (NIH), aiming to reshape the local immune environment by restoring macrophage lysosomal function. This research is currently in the in vitro and animal experiment stage, and the results still require validation through clinical human trials.