Sylma R. Gottlieb, a piano, voice and music teacher in Bowie, Md., for 49 years, died Dec. 14 at her home in Bowie. She was 91. The cause was pancreatic cancer, said her daughter Nancy Bort. Besides her teaching career, Mrs. Gottlieb sang in several opera companies, directed a number of choral groups and was a guild teacher and judge in Bowie.