Immunocompetent cells adjacent to stainless steel and titanium miniplates and screws

Abstract

Subepithelial soft tissue and bone obtained from the implant bed in the vicinity of stainless steel and titanium miniplates and screws were evaluated with respect to the presence of immunocompetent cells. The study included tissue specimens from 19 patients, in whom the implants (14 stainless steel and 5 titanium) had been in situ for more than 6 months. The ABC (avidin-biotin-complex) immunoperoxidase staining technique using monoclonal antibodies defining T lymphocytes (CD3+), macrophages (CD11c+) and Class II MHC (HLA-DR) was performed on EDTA demineralized, frozen bone tissue, and on fresh frozen soft tissue specimens. The results showed scattered T lymphocyte clusters, small numbers of macrophages and abundant expression of HLA-DR in the soft tissue adjacent to both stainless steel and titanium implants. There was no substantial difference in tissue reactions between implants of the two materials. The demineralized bone sections disclosed presence of immunocompetent cells in the connective tissue lining the periphery of the screw holes. Metal particles were seen in both the soft tissue and the bone specimens. We conclude that a mild tissue reaction takes place in the vicinity of miniplates and screws of stainless steel and titanium, and that the intensity of the reaction indicates that the implants are well tolerated by the host tissue.

Evaluation of metal release and local tissue response to indigenous stainless steel miniplates used in facial fractures

“…This is in consensus with the findings of Torgerson S et al [5]. One case (20%) from symptomatic group displayed F.B.…”

“…This is comparable with Torgersen S et al [5] who observed increased fibroblasts in the peri-implant tissue. No degenerative changes were observed in any of the cases in either group.…”

“…This finding is comparable with Torgersen S et al [5] who observed fibrosis and mild inflammation around the stainless steel miniplates.…”

Hypersensitivity Reactions to Implanted Metal Devices: Facts and Fictions

“…The occurrence is evidenced by findings of elevated levels of a range of immune cells and markers found in peri-implant tissue at various time intervals after implantation, including CD3 + and CD4 + T lymphocytes, CD11c + macrophages/dendritic cells, and cells with abundant expression of MHC class II (human leukocyte antigen-DR) (dendritic cells) [158][159][160]. In addition, significant levels of metal ions can be found in various parts of the body, including capsular and periprosthetic tissues, distant organs (liver, spleen, lymph nodes), and in the urine and serum of patients undergoing total hip arthroscopy [161][162][163][164][165][166].…”

“…In the effector phase, metal ions that are released may activate the immune system by binding to endogenous proteins to form metal-protein complexes, which are recognized by T lymphocytes as antigens and elicit hypersensitivity reactions [9,160,174,175]. Nickel, however, may act as a superantigen and directly activate T-cell receptors [176].…”