BACKGROUND Pedicle screws with PMMA cement augmentation have been shown to significantly improve the fixation strength in a severely osteoporotic spine. However, the efficacy of screw fixation for different cement augmentation techniques, namely solid screws with retrograde cement pre-filling versus cannulated screws with cement injection through perforation, remains unknown. This study aimed t...

The cement-in-cement technique is useful in the setting of revision total hip arthroplasty (THA), especially to gain acetabular exposure, change a damaged or loose femoral component, or change the version, offset, or length of a fixed femoral component. The goal of this retrospective study was to assess the clinical and radiographic characteristics of revision THA using the cement-in- cement te...

After cemented total hip arthroplasty (THA) there may be failure at either the cement-stem or the cement-bone interface. This results from the occurrence of abnormally high shear and compressive stresses within the cement and excessive relative micromovement. We therefore evaluated micromovement and stress at the cement-bone and cement-stem interfaces for a titanium and a chromium-cobalt stem. ...

Acrylic bone cement is self-curing cement comprising of liquid and powder component of methyl methacrylate (MMA). It has been used extensively in orthopedics; however, adverse effects were associated with its use. Hence we investigated in this paper the possibility of new cement utilizing methacrylates with lower toxicity than MMA. LD50s of candidate monomers were determined with administration...

Carbon nanotubes (CNTs) have shown promise for improving the mechanical performance of cement composites through crack-bridging and frictional pull-out. The interactive behaviors between CNTs and cement matrix act are crucial in optimizing the reinforcement of CNTs in cement composites. This study investigates the effects of nano-silica (NS) sol-gel on the interactive behaviors of CNTs and the ...

The initial composition of acrylic bone cement along with the mixing and delivery technique used can influence its final properties and therefore its clinical success in vivo. The polymerisation of acrylic bone cement is complex with a number of processes happening simultaneously. Acrylic bone cement mixing and delivery systems have undergone several design changes in their advancement, althoug...

STATEMENT OF PROBLEM Crowns cemented on short implant abutments may have insufficient retention. PURPOSE The purpose of this study was to evaluate the effect of circumferential grooves on the retention of cemented cast copings on implant abutments. MATERIAL AND METHODS Sixty similarly-shaped implant abutments were divided into 4 groups (n=15): without grooves, with 1 groove, with 2 grooves,...

We previously showed that otx2 activates ectopic formation of the Xenopus cement gland only in ventrolateral ectoderm, defining a region of the embryo permissive for cement gland formation. In this paper, we explore the molecular identity of this permissive area. One candidate permissive factor is BMP4, whose putative graded inhibition by factors such as noggin has been proposed to activate bot...

AIM The present study seeks to increase the life term of fully cemented total hip replacements by minimizing the stress values within the cement mantle. METHODS Three-dimensional (3D) finite element analyses have been carried out to investigate the effects of varying cement thickness on the von-Mises stress of a cement mantle. The magnitude and location of maximum von-Mises stress within the ...

When aseptic failure of the bond between the cement and the prosthesis of a total joint replacement occurs, complete removal of the cement has been advocated before the insertion of a new prosthesis. The present study questions this practice. Both laboratory tests on variously prepared specimens of cement and clinical experiences demonstrate that recementing over old cement is a practical alter...