• Martin Emerson has been promoted to president and CEO of American Medical Systems Holdings (AMS; Minneapolis) from his current role as president and chief operating officer. Emerson also has been named a director. Chairman and CEO Douglas Kohrs will remain as chairman of the board. AMS is a diversified supplier of medical devices and procedures to cure erectile dysfunction, benign prostatic hyperplasia, incontinence and other pelvic disorders in men and women.

• Scott Root has been named president and CEO of Astra Tech (Waltham, Massachusetts), part of the AstraZeneca group. He also will serve on the company's board of directors. Root most recently was senior vice president of Straumann USA, a medical device company focused in implant dentistry and tissue regeneration. Astra Tech is the U.S. subsidiary of Astra Tech AB, a manufacturer of dental implants and medical devices for surgery and urology. The company is launching its OsseoSpeed Dental Implant in the first quarter, which it said is the first such implant with a bone growth catalyst.

• Eric Nodiff was named senior vice president and general counsel of Cantel Medical (Little Falls, New Jersey), a provider of infection prevention and control products. Nodiff is a former partner in the law firm of Dornbush Schaeffer Strongin & Weinstein.

• Jerry Blair has been promoted to vice president of business operations at CDEX (Rockville, Maryland). Blair joined the company last May as director of healthcare marketing. CDEX develops real time spectral-related identification of substances including explosives, illegal drugs and medications.

• Phillip Vorwald has been named vice president, worldwide sales at Guava Technologies (Hayward, California). Vorwald joins Guava from Delphi Medical Systems, where he served as managing director. Guava's product offerings combine rugged and reliable instrument platforms with a variety of assays and software modules to provide complete solutions for on-demand cellular analysis.