Progress in fine material test piece evaluation technology.

Progress in device technology.

Advances in implantable device technology over the past few years can be seen in these illustrations. The photograph on the left shows a 1997-model implantable cardioverter-defibrillator (ICD) in front of an older version. Beside it is a modern single-chamber pacemaker in front of an older mercury-zinc–cell model. The Table shows their relative weights. These devices are now small enough to per...

Progress in artificial chromosome technology.

Artificial chromosomes is an exciting technology which has developed rapidly since the late 1990s. HACs (human artificial chromosomes) are autonomous molecules that can function and segregate as normal chromosomes in human cells. The advantages of an artificial-chromosome-based system are 2-fold. First, HACs are an excellent research tool for investigating the requirements for normal chromosome...

Progress in material design for biomedical applications.

Biomaterials that interface with biological systems are used to deliver drugs safely and efficiently; to prevent, detect, and treat disease; to assist the body as it heals; and to engineer functional tissues outside of the body for organ replacement. The field has evolved beyond selecting materials that were originally designed for other applications with a primary focus on properties that enab...

Progress in Medical Laboratory Technology

Torque Removal Evaluation of Screw in One-Piece and Two-Piece Abutments Tightened with a Handheld screwdriver

Introduction: Some clinicians use a handheld screw driver instead of a torque wrench to definitively tighten abutment screws. The aim of this study was to compare the removal torque of one-piece and two-piece abutments tightened with a handheld driver and a torque control ratchet. Methods: 40 ITI implants were placed in acrylic blocks and divided into 4 groups. In groups one and two, 10 ITI one...