The fourth of six people infected with the AIDS virus by a dentist died Saturday.

Barbara Webb, 68, slipped into a semi-coma earlier in the week, according to Hospice of Martin. She died on the 45th anniversary of her marriage to her husband, Robert."She was never bitter about her death," said hospice counselor Pam Jett. "She didn't dwell on the future, she lived in the present."

Two years ago, a federal study concluded that six of Dr. David Acer's patients contracted HIV from him. Scientists are baffled as to precisely how Acer transmitted the virus.

Acer, of Jensen Beach, Fla., died in 1990. He is the only health professional ever known to have transmitted HIV to his patients.

Among those infected was Kimberly Bergalis, who waged a crusade for mandatory testing of health-care workers before she died in December 1991.

Webb, a former high school English teacher and grandmother of eight, gave dozens of speeches nationwide about living with AIDS. She was the teacher of the year in 1986-87 at Martin County High School.

Webb is survived by her husband and three grown children.