©2015 by The Orthopaedic Journal at Harvard Medical School BACKGROUND Shoulder arthroplasty procedures have generally excellent clinical outcomes, but infection following shoulder arthroplasty continues to be a difficult problem both diagnostically and therapeutically. Two-stage reimplantation with use of a temporary Prosthesis of Antibiotic-Loaded Acrylic Cement (PROSTALAC) (DePuy, Warsaw, Ind...

Tensile bond strength and failure location were evaluated in vitro for three types of direct bonding cements (unfilled, low filled, and highly filled) with three types of brackets (polycarbonate, stainless steel, and ceramic) using natural teeth and plastic as substrates. An unfilled acrylic cement gave the highest values of bond strength for both the plastic and ceramic brackets, whereas a hig...

Objective. Aim to study how the content of alendronate affected shear strengths at bone-bone cement-metal interfaces. Methods. All samples were divided into 6 groups, G0-G5. On the 1st and 60th day after surgery, bone-bone cement interface shear strengths and bone densities were examined. Interface strengths of metal-bone cement specimens were studied before immersion and 4 weeks after immersio...

BACKGROUND Although shoulder arthroplasty is an accepted treatment for osteoarthritis, loosening of the glenoid component, which mainly occurs at the bone-cement interface, remains a major concern. Presently, the mechanical effect of the cement mantel thickness on the bone-cement interface is still unclear. METHODS Finite element analysis of a prosthetic scapula was used to evaluate the effec...

Modern cementing techniques aim to improve the interlock between bone and cement and to establish a durable interface. Cement penetration is generally believed to influence interface failure, but current methods for improving the cement-bone interface are inadequate. Oscillation is the reciprocated movement of an object through its balanced position, or the quantum physics of systematic fluctua...

OBJECTIVE To compare biomechanical strength, interface quality, and effects of bone healing in bone-implant interfaces that were untreated or treated with calcium phosphate cement (Ca-cement), magnesium phosphate cement (Mg-cement), or polymethylmethacrylate (PMMA) in horses. ANIMALS 6 adult horses. PROCEDURES 4 screw holes were created (day 0) in each third metacarpal and third metatarsal ...

This study compared the mechanical strength of commercially prepared antibiotic bone cement (Simplex With Tobramycin; Stryker, Mahwah, NJ), cement with generic tobramycin (Pharma-Tek, Huntington, NY) blended in by the orthopedic nursing staff, and standard nonantibiotic bone cement. The results showed an approximate 36% decrease in the strength of the cement with hand-mixed generic tobramycin, ...

BACKGROUND AND PURPOSE Despite the longstanding use of micromotion as a measure of implant stability, direct measurement of the micromechanics of implant/bone interfaces from en bloc human retrievals has not been performed. The purpose of this study was to determine the stem-cement and cement-bone micromechanics of functionally loaded, en-bloc retrieved, cemented femoral hip components. METHO...

T bite-block rapid maxillary expander, introduced by McNamara,1 is widely used in orthodontic practice for its ability to control molar ex trusion in hyperdivergent patients through muscletone activation. One disadvantage of a bonded expander is that acrylic coverage of the premolars and molars makes it difficult to monitor the progress of arch expansion. We have developed a technique for placi...

We applied an axisymmetric model of the tibia to a finite element method and analyzed the heat conduction from bone cement in total knee arthroplasty using numerical simulation with the finite element analysis software, ABACUS. We hypothesized the thermal necrotic map of bone. Moreover, we suggested a method for preventing thermal necrosis of bone using this simulation. We adopted an initial te...