Improvement of the long-term adhesive strength between metal stem and polymethylmethacrylate bone cement by a silica/silane interlayer system

Abstract

A loss of adhesive strength between metal stem and bone cement is clinically found to be a serious problem in total hip arthroplasty and causes many operative revisions. The objective of this study was to improve the long-term adhesive strength at this interface. A new silica/silane interlayer coating system is introduced. The layers are designed to bond the metal stem surface to the polymethylmethacrylate bone cement marginally leakage free. In vitro tensile tests were performed on specimens of TiAl6V4 and CoCrMo that were cemented by pairs with different bone cements with and without the new coating system. The specimens were stored in isotonic saline solution up to 150 days. The adhesive strength decreased about 75% within 30 days of storage on specimens of both metal alloys that were conventionally cemented without the new interlayer system. With the new coating, the high initial adhesive strength (40-50 MPa) could be stabilized for TiAl6V4 over 150 days. For the same 150-day storage period, the adhesive strength of the coated CoCrMo alloy still decreased but the decrease was only half that experienced by the uncoated CoCrMo. The loss of adhesive strength on CoCrMo specimens could be reduced if the metal surface was activated by a plasma treatment. The new coating interface system could help to considerably reduce revision operations caused by debonding effects at the interface metal/polymethylmethacrylate bone cement.

Influence of femoral stem surface finish on the apparent static shear strength at the stem–cement interface

“…It is generally accepted that long term durability of cemented THR requires meticulous attention to three elements and two interfaces, which are femoral stem, Great effort has been made to investigate the factors influencing the bond strength at the stem-cement interface, such as increasing stem surface roughness (Chen et al, 1998;Lennon et al, 2003;Ohashi et al, 1998), pre-coating the stem (Fischer et al, 2001;Morita et al, 1997) and utilising "modern cementing techniques" (Geiger et al, 2001;Mulroy Jr. and Harris, 1990). The optimum surface finish of the femoral stem has been the focus of controversy for a long time, mainly concentrating on whether matt stems could accomplish permanent fixation during their in vivo service (Alfaro-Adrian et al, 2001;Shen, 1998).…”

Nonthermal plasma on the shear bond strength of relining resin to thermoplastic denture base resin

“…15 In the previous studies, it is reported that surface modification using plasma treatment have improved the bonding strength between heat cured acrylic resin and self-curing acrylic resin. 16,17 The purpose of this study was to evaluate the effect of nonthermal plasma treatment on the bond strength of the autopolymerizing relining resin material to thermoplastic denture base resins in comparison to different surface treatments.…”

Surface pretreatments for medical application of adhesion

“…The corresponding number for the Co alloy was 46%. As a striking feature it should be mentioned that the stability for the Ti alloy was much better than that of the Co alloy [29,30]. …”