a 16-year-old class ii female patient was treated without tooth extraction. the upper first molars were distalized by the pendulum appliance. after six months, the molars tipped significantly to the distal. to correct this side effect, we decided to upright the molars using skeletal anchorage. on each side, a mini-screw was inserted between first and second premolars in the buccal cortical plat...

conclusions the functional outcome 22 months post injury showed that although primary treatment method uses locked imn in humeral shaft fractures, unlocked imn can be used in appropriate cases. less injury risk to the axillary and radial nerve, short period of surgery, and less radiation can be considered as advantages of this technique. introduction although intramedullary nailing (imn) is use...

BACKGROUND Screw fixation of pelvic ring fractures is a common, but demanding procedure and navigation techniques were introduced to increase the precision of screw placement. The purpose of this case series was the evaluation of screw misplacement rate and functional outcome of percutaneous screw fixation of pelvic ring disruptions using a 2D navigation system. METHODS Between August 2004 an...

The intention of this study was to compare the biomechanical characteristics using 5 internal fixation methods used clinically to stabilize a pubic symphysis diastasis (PSD, Tile type B1).A 3-dimensional finite element model of PSD was simulated using 5 implants, including single superior plate (Single-Plate), superior and anterior plate (Dual-Plate), single cannulated screw (Single-Screw), cro...

A three-dimensional simulation of trabecular surface remodeling was performed to investigate the basic effects of a fixation screw on the trabecular structural changes in a vertebral body. Voxel-based finite elements were used to construct computational models of the bone and screw for an entire vertebral body with the screw and for the bone-screw interface. The remodeling simulation for the en...

STUDY DESIGN Evaluation using 3-dimensional screw trajectory software and computed tomographic scans. OBJECTIVE To investigate the anatomic feasibility of laminar screw placement in the upper thoracic spine compared with pedicle screw placement. SUMMARY OF BACKGROUND DATA Although laminar screws have been suggested as an alternative to pedicle screws in the upper thoracic spine, previous an...

We report a case of fixation of a scaphoid fracture using an Acutrak(®) screw. This screw is cannulated and headless, which allows it to be implanted below the surface of the bone. It uses the same concept of variable thread pitch as the Herbert screw, but unlike the Herbert screw, is fully threaded, with continuously varying pitch along its length. This variable pitch creates constant compress...

the potential use of nano technology for improving of withdrawal resistance of nail and screw in wood was evaluated. for this, the maintenance strength of nail and screw was measured under dry and wet conditions for poplar wood (populus nigra) coated with common paints in furniture industry and nano-particles. specimens with dimensions of 15×5×5 cm3 (l×r×t) were cut from poplar wood (populus ni...

AIM In unique clinical situations where C1-C2 posterior fixation is not available or has previously failed, an anterior transarticular screw (ATAS) may be a viable alternative. However, there are no previous reports that investigate possible screw angles, screw entry points, and screw length based on computed tomography (CT) multiplanar reconstruction images in Turkish patients. The aim of this...

Introduction: Anterior spinal instrumentation of the thoracic and lumbar spine has gained in popularity since Dwyer et al [1] developed the cable system in 1964. However, implant loosening, screw breakage and cut-throughs have been noted clinically when using Dwyer or Zielke's Ventrale Derotations Spondylodese (VDS) instrumentations [2,3]. To avoid these complications and pseudarthrosis, one ma...