Abstract: Load-bearing cold-formed steel (CFS) walls sheathed with double layers of gypsum plasterboard on both sides have demonstrated good fire resistance and attracted increasing interest for use in mid-rise CFS structures. As the main connection method, screw connections between CFS and gypsum sheathing play an important role in both the structural design and fire resistance of this wall sy...

Progressive loosening of bone fixation screws is a well-documented phenomenon, induced by stress shielding and subsequent adaptive bone remodeling which results in bone loss around the screw. A set of two-dimensional computational (finite element) models was developed in order to test the effect of various engineering designs of fixation screws on the predicted screw-bone stress transfer, and c...

Foreign body reactions may occur in patients who receive bioabsorbable implants during orthopedic surgery for fractures and ligament repair. The authors describe a 34-year-old man who presented with a palpable tender mass on the lateral aspect of the left knee of 1 month's duration. He underwent posterior cruciate ligament and posterolateral corner reconstruction 3 years earlier. Physical exami...

The aim of this study is to minimize the specific energy consumption of the screw wash-sand machine. Let the diameter of the screw structure, pitch, diameter of the screw axis, blade thickness, installation angle, and the speed of the screw axis be the design variables, and take the minimum specific energy consumption as the optimization objective. According to the complexity of the optimizatio...

In this study, screw and nail withdrawal resistance of fir (Abies nordmanniana), oak (Quercus robur L.) black pine (Pinus nigra Arnold) and Stone pine (Pinus pinea L.) wood were determined and compared. The data represent the testing of withdrawal resistance of three types of screws as smart, serrated and conventional and common nails. The specimens were prepared according to TS 6094 standards....

Pedicle screw loosening has been implicated in recurrent back pain after lumbar spinal fusion, but the degree of loosening has not been systematically quantified in patients. Instrumentation removal is an option for patients with successful arthrodesis, but remains controversial. Here, we quantified pedicle screw loosening by measuring screw insertion and/or removal torque at high statistical p...

BACKGROUND Surgical treatment of acetabular fractures is one of the greatest challenges for orthopedic surgeons. Fixation of most displaced fractures requires extensive exposure, which may lead to complications, including blood loss, neural or vascular injury, postoperative infection, wound healing problems, and heterotopic bone formation. MATERIAL AND METHODS This study was conducted to certif...

UNLABELLED Screw-retained implant crowns may be clinically demanding, especially managing the esthetic and occlusal challenges of screw access channel closure. Many clinicians have moved away from using screw retention as a means of fixing a crown to an implant in favor of cementation to an underlying abutment. A link has been established between peri-implant disease and excess cement extrusion...

INTRODUCTION Pedicle screw fixation in a severely osteoporotic spine remains a challenge for orthopaedic surgeons. Previous studies have demonstrated that pedicle screw fixation is highly correlated to the bone mineral density [1], and increasing the screw’s pullout strength can be achieved using a variety of methods, these include the use of pedicle screws with various designs [2,3]. However, ...

one of the complications during a routine dental implant placement is accidental ingestion of the implant instruments, which can happen when proper precautions are not taken. appropriate radiographs should be taken to locate the correct position of foreign body; usually the foreign body passes asymptomatically from gastrointestinal tract but sometimes it may lead to intestinal obstruction, perf...