1985Year EVERY mother's admonition to ''Brush your teeth before you go to bed,'' may in a decade or two include the semiannual demand, ''And don't forget to take your anti-cavity pill!'' Since the late 1960's, when scientists determined that tooth decay was an infectious disease, the search has been on for an anti-cavities vaccine. Now some researchers say that such a vaccine, taken either by capsule or injection, could reach consumers by the mid-1990's. The vaccine would be especially valuable, they say, in third world countries that do not have fluoridated water. WHAT'S NEW IN DENTISTRY

1950Year ARDMORE, Pa. June 11--It was inevitable, of course, that there would be something of an anti-climax to the open champion ship in today's play-off. There usually is to every play-off. But what set this one apart from all the others was that, in some respects, it was reminiscent of the Los Angeles Open of last January. You remember that, don't you? Sports of the Times

1953Year NEW DELHI, India, Nov. 28 -- Defying Chinese Communist occupation authorities, the Dalai Lama of Tibet has refused to fly the Red flag of Mao Tse-tung over the sacred Potala Palace in Lhasa. Tibet Ruler Bars Red China Flag

1953Year Communists reptd forced to withdraw 1/3 of troops Tibet Ruler Bars Red China Flag

1950Year Austrian Communists rept 400,000 sign resolution VIENNA RED RALLY DRAWS SLIM CROWD

1994Year A PUBLIC service campaign has, for the first time, won a prestigious prize for advertising effectiveness. The Partnership for a Drug-Free America and two agencies that created national television commercials intended to help "unmarket" drugs among children living in the inner city were awarded the Grand Effie last night at the 26th annual Effie Awards ceremony in New York. It was the first time since the Grand Effie was created in 1978 that it was awarded for public service work. THE MEDIA BUSINESS: Advertising