Metal particles and tissue changes adjacent to miniplates A retrieval study

Abstract

Peri-implant soft tissue and bone from 12 patients undergoing removal of stainless steel miniplates and screws after healing of jaw fractures were studied with regard to histomorphology and metal content. Three patients with titanium plates were also included. Light microscopy and scanning electron microscopy with energy-dispersive X-ray microanalysis were used. Non-osseous tissue adjacent to devices of both materials showed fibrosis, including areas of mild chronic inflammation. The cellular picture was dominated by fibroblasts with small aggregates of lymphocytes and scattered macrophages. A connective tissue collar was found between the bone tissue and the screws of both stainless steel and titanium. Bone formation was also evident adjacent to screws of both materials. Stainless steel or titanium particles 5-50 microns in diameter were found in both soft tissue and bone next to implants of their corresponding bulk material. The amount of metal impregnation varied between individual sections, and fewer particles were found in the bone specimens than in soft tissue. The mild inflammatory changes were not restricted to areas of metal impregnation.

Release of metals from osteosynthesis implants as a method for identification: post-autopsy histopathological and ultrastructural forensic study

“…These findings are similar to those reported in the literature for studies of maxillofacial and orthodontic implants and prostheses [5,7,20,21]. No granulomatous inflammation caused by the foreign body was seen in any case [13,20,21]. Optical microscope examination of samples taken further from the fixation area was negative in all cases.…”

“…biomaterials designed to be included in a biological system and to support or replace an anatomic function [1,2], are used in the treatment of bone fractures; their application can provide a temporary surgical fixation of bones, removed once the fracture has repaired, or a permanent, irremovable fixation. The study of interaction between these structures and human tissues had the aim to establish any harmful long-term metabolic effects, mostly on animal samples [3][4][5][6][7][8][9] and, on humans, in the areas of maxillofacial and orthodontic surgery [10][11][12][13]. In forensic work, studies generally focus on autopsy cases where the presence of metal implants still in situ can provide important information, especially with respect to identification [14].…”

Systemic and Local Tissue Response to Titanium Corrosion

“…In various cases the products of corrosion were found around the blood vessels (Fig. 2 C), in keeping with the histological study of soft tissue adjacent to titanium implants reported by Meachim & Williams (1973) and Torgersen et al (1995). The observation of metal particles located intracellularly or in association with vessels may represent a biologic response aimed at eliminating the foreign material (Meachim & Williams, 1973;Schliephake et al, 1993;Torgersen et al, 1995).…”

Sister chromatid exchanges and ion release in patients wearing fracture fixation devices

“…Our results agree with other authors 21 who, studying fracture fixation devices made of stainless steel after retrieval, have observed corrosion phenomena to a great extent. That is, the crevices between the different components were the sites of corrosive attacks that led to corrosion defects in the countersink areas in 64-100% of the examined plates.…”