NEW YORK (AP) _ A plastic surgeon convicted of killing his wife 15 years ago and dropping her body into the ocean was sentenced Wednesday to 20 years to life in prison.

State Supreme Court Justice Leslie Crocker Snyder said trial evidence made it ``absolutely overwhelmingly clear'' that Robert Bierenbaum, 45, had killed Gail Katz-Bierenbaum, 29, in 1985. Her body was never found.

``We can only tell by the circumstances after the crime how cold-blooded, brutal and vicious it was,'' Snyder said. She said evidence suggests ``he dismembered Gail, squeezed her into a bag, and dropped her from a plane.''

Bierenbaum, who says he is innocent, did not address the court. Defense lawyer Scott Greenfield said Bierenbaum was worried he might hurt his appeal chances.

Greenfield had asked Snyder to impose the minimum sentence, 15 years in prison, telling her that Bierenbaum is a good man who is ``not a danger to society.'' He cited his client's free treatment of impoverished children in Mexico's rural areas.

Snyder noted that the jury convicted Bierenbaum without hearing psychiatric evidence about ``how much he hated Gail and how much he wanted to kill her.'' The judge had barred much of that evidence as prejudicial.

Prosecutors said Bierenbaum probably strangled his wife in their New York apartment after she told him she was leaving their sometimes violent marriage for another man.

They said Bierenbaum put his wife's corpse in a duffel bag, took it up in a small plane and dropped it into the ocean off New Jersey or Long Island.

Bierenbaum, who waited 30 hours before reporting his wife missing, told detectives that after he and his wife argued the morning of July 7, 1985, she went to Central Park to cool off and never came home.

Bierenbaum remarried, moved to Grand Forks, N.D., and has a 2-year-old daughter. His new wife was in court for most of the trial and during his sentencing.