Hydroxyapatite coating of prostheses.
نویسنده
چکیده
The basic problem with the fixation of a prosthesis, cemented or cementless, is biomechanical. The forces transmitted between it and bone will depend on the design and the surface geometry of the implant, the mechanical properties of its surface, and the operative technique. Biological problems may arise from the relative biocompatibility of the implant surface, its biochemistry, the quality of the bone bed, and the degree and duration of early fixation. The aim of cementless implantation is to ensure osseo-integration : to achieve permanent fixation ofthe prosthesis in its bony surroundings with no interposed connective tissue. The focal point for research is therefore the interface. At first, forces will be transmitted mainly in compression. This means that cementless implants must be designed to achieve primary stability and to transmit forces as orthogonal stress components wherever possible. Apart from its geometrical design, the second major factor determining success or failure is the surface of the implant. Roughening ofthe surface can increase the area interfacing with bone. Plane, smooth metallic surfaces transmit compression forces only, but bony ingrowth into a porous surface permits the transmission of some tensile and shear loads. Roughening of the surface, therefore, not only enlarges the available area, but also increases resistance to shear forces. However, an increase in surface area makes the biocompatibility of any coating material of even greater significance. With the exception of titanium, metal surfaces can corrode and this may release ions into the surrounding tissues. The larger the surface, the more ions are released. The most biocompatible materials now in clinical use are titanium and its alloys, and hydroxyapatite. The use of hydroxyapatite ceramic as a coating for femoral components of hip arthroplasties is the subject
منابع مشابه
The effect of adhesive strength of hydroxyapatite coating on the stability of hydroxyapatite-coated prostheses in vivo at the early stage of implantation
INTRODUCTION With the increase in joint revision surgery after arthroplasty, defects of hydroxyapatite (HA)-coated prostheses have been observed increasingly often. These defects adversely affect the prosthetic stability in vivo. This study has analyzed the potential effect of the adhesive strength of HA coating on the stability of HA-coated prostheses in vivo after its implantation. MATERIAL...
متن کاملA six-year study of hydroxyapatite-coated root-form dental implants.
BACKGROUND The effect of hydroxyapatite coating of dental implants is controversial. The long-term fate of hydroxyapatite-coated implants has been the subject of some criticism. PURPOSE The aim of this retrospective study was to assess the clinical outcome of hydroxyapatite-coated cylindrical root-form endosseous Impladent dental implants (LASAK Ltd, Prague, Czech Republic) during a six-year ...
متن کاملThermal processing of hydroxyapatite for coating production.
Thermally processed hydroxyapatite coatings used on dental implants and hip prostheses for enhanced fixation may typically consist of a number of chemical and structural phases. These phases affect coating performance and tissue attachment. Hydroxyapatite was plasma sprayed to examine the phase evolution during processing. Coatings were examined with X-ray diffraction and elemental analysis. Re...
متن کاملA biodegradable gentamicin-hydroxyapatite-coating for infection prophylaxis in cementless hip prostheses.
A degradable, poly (lactic-co-glycolic acid) (PLGA), gentamicin-loaded prophylactic coating for hydroxyapatite (HA)-coated cementless hip prostheses is developed with similar antibacterial efficacy as offered by gentamicin-loaded cements for fixing traditional, cemented prostheses in bone. We describe the development pathway, from in vitro investigation of antibiotic release and antibacterial p...
متن کاملCementless Hydroxyapatite Coated Hip Prostheses
More than twenty years ago, hydroxyapatite (HA), calcium phosphate ceramics, was introduced as a coating for cementless hip prostheses. The choice of this ceramic is due to its composition being similar to organic apatite bone crystals. This ceramic is biocompatible, bioactive, and osteoconductive. These qualities facilitate the primary stability and osseointegration of implants. Our surgical e...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of bone and joint surgery. British volume
دوره 73 5 شماره
صفحات -
تاریخ انتشار 1991