The US Patent Office has issued Patent No. 6,419,491 to Bio-Lok International Inc. for its Laser-Lok micro-grooved laser machined dental implant.   . . .   ST Assembly Test Services Ltd. (STATS), an independent semiconductor test and advanced packaging service provider, has announced the appointments of Peter Seah Lim Huat, Tay Siew Choon and Tan Choon Shian to its board of directors, effective July 15. Premod Paul Thomas and Liow Voon Kheong have resigned from the board and will be replaced by alternate directors Gan Chee Yen and Lai Yeow Hin. In June, the company appointed Tan Lay Koon as its president and CEO and as a director. Lay Koon, previously STATS' CFO, succeeded Harry Davoody, who resigned to pursue interests in the US.