Distal flow of polymethylmethacrylate (PMMA) bone cement during insertion of the femoral implant results in reduced pressure and cement-bone interdigitation (Markolf, Amstutz, 1976). Insertion of femoral cement plugs in the intramedullary canal to prevent distal flow of PMMA cement in total hip replacement during cementing of femoral prostheses is well accepted and has become current practice (...

A new wear testing system, which carries out toothbrush wear and simulated occlusal wear tests alternately, was developed. Differences in wear behavior among three modes of wears, combined wear, toothbrush wear and simulated occlusal wear, were investigated using polymethylmethacrylate (PMMA) and two commercial resin composites (Z100, APX). The area of the material loss after each test was meas...

The dynamics and morphology of a liquid polystyrene (PS) film on the scale of a hundred nanometer dewetting from a liquid polymethylmethacrylate (PMMA) film is investigated experimentally and theoretically. The polymers considered here are both below their entanglement lengths and have negligible elastic properties. A theoretical model based on viscous Newtonian flow for both polymers is set up...

We exposed human macrophages isolated from the peripheral blood of healthy donors to metal and bone-cement particles from 0.2 to 10 microm in size. Zymography showed that macrophages exposed to titanium alloy and polymethylmethacrylate (PMMA) particles released a 92- and 72-kDa gelatinase in a dose- and time-dependent manner. Western immunoblotting confirmed that the 92- and 72-kDa gelatinolyti...

Balloon kyphoplasty has been shown to be safe in treatment of vertebral compression fractures refractory to conservative management. However, few reports have focused on lateral wedging of cemented vertebra after kyphoplasty. A 72-year-old woman with a T12 osteoporotic compression fracture underwent kyphoplasty using polymethylmethacrylate (PMMA) via a bipedicular approach. The patient felt pai...

We evaluated comparatively the mechanical strength in three kinds of surgical fixation techniques for canine atlantoaxial joint. Atlantoaxial plate fixation (APF), polymethylmethacrylate (PMMA) fixation (PMF) and transarticular fixation (TAF) were applied to the atlas and axis harvested from healthy beagle dogs, and then, the specimens were tested. The PMF group had significantly higher resista...

BACKGROUND In cases where autologous bone graft reconstruction is not possible (such as comminuted fractures, bone graft reabsorption, or infection) and the use of synthetic material is required, polymethylmethacrylate (PMMA) use is a safe and efficient solution. Studies comparing the incidence of postoperative complications between autologous and synthetic cranioplasty are heterogeneous, not a...

Platelets adhere to artificial surfaces in the initial stage of thrombus formation, but the subsequent steps in signal transduction that lead to platelet activation by artificial surfaces are not understood. When 0.325-micron diameter beads composed of a hydrophobic polymer, polymethylmethacrylate (PMMA), were added to gel-filtered aequorin-loaded platelets suspended in media containing Ca2+, t...

Clinical outcome of cemented implants to revision total hip replacement (THR) is not as satisfactory as primary THR, due to the loss of bone stock and normal trabecular pattern. This study evaluated a bioactive bone cement, strontium-containing hydroxyapatite (Sr-HA) bone cement, in a goat revision hip hemi-arthroplasty model, and compared outcomes with polymethylmethacrylate (PMMA) bone cement...

BACKGROUND AND PURPOSE Sacroplasty is not as routinely performed as vertebroplasty, possibly due to technical challenges and the paucity of data regarding subsequent outcomes. The first goal of the present investigation was to describe a technique for sacroplasty that facilitates safe needle placement and polymethylmethacrylate (PMMA) extrusion. The second goal was to perform finite element ana...