Bone ingrowth behaviour of hydroxyapatite-coated, polyethylene-intruded and uncoated, sandblasted pure titanium implants in an infected implantation site: an experimental study in miniature pigs

Abstract

We studied the dynamics of bone tissue ingrowth into the pores of hydroxyapatite-coated (plasma-spraying technique) and uncoated wire meshes of pure Ti in an infected implantation site. Samples of the test materials were implanted into the femora of 15 adult G6ttingen minipigs. Just before implantation they were contaminated with Staphylococcus aureus. The pigs were killed after 4, 8, 12 or 24 weeks. Undecalcified ground sections of bone tissue were prepared and stained with toluidine blue for comparative histological evaluation. The hydroxyapatite-coated implants already demonstrated advanced new bone formation after 4 weeks. By 12 weeks most of the implant pores were filled with newly formed bone although all samples showed macro-as well as microscopic signs of persistent infection. Comparable reactions of the uncoated implants could be observed only after 24 weeks. Signs of degradation of the hydroxyapatite coating were seen in contact with soft tissue. This was more extensive in the infected than in the uninfected site. The results and possible clinical consequences are discussed.

Osseointegration of hydroxyapatite‐coated and noncoated Ti6Al4V implants in the presence of local infection: A comparative histomorphometrical study in rabbits

“…These data, in combination with the negative correlation between the number of colony forming units at sacrifice with the distal bone contact, indicate when bone‐implant contact is considered to be related to implant fixation,33 that a clear relationship exists between peri‐implant infection and decreased implant fixation. Wilke et al34 demonstrated for HA‐coated implants good osseous ingrowth behavior in spite of local infection. We therefore speculate that the histomorphometrical findings were not directly related to the implant type, but related to the severity of the infection, because the HA implants revealed more severe infections 22.…”

Biocompatibility analysis of different biomaterials in human bone marrow cell cultures

“…17,18 The same biomaterials were applied in patients. The results using osseointegration of HA, titanium, and PE in animal experiments and in patients were comparable to those (cell adherence and ECM) in the cell culture system).…”

Case reports - Infection following total hip arthroplasty with a hydroxyapatite-coated prosthesis: Histology and histomorphometry 6 years after implantation and infection a case report

“…This is also consistent with earlier findings (Tonino et al 1999) and confirms that bone ongrowth to the stem followed a normal pattern in this patient, notwithstanding the infection. Experimental studies in miniature pigs also have shown good osseous ingrowth of bone with HA-coated implants despite a local infection (Wilke et al 1993). Rabbit studies have shown that local infection can affect histomorphometric parameters: in severe infections, the bone-implant contact ratio has been found to be smaller in HA implants than in uninfected HA implants and uncoated implants (Oosterbos et al 2002).…”