Dr. Hito Suyehiro, 54, an orthodontist who had practiced in this area since the late 1950s, taught at Howard University and was active in professional organizations, died Feb. 4 at Suburban Hospital after a heart attack. He lived in Rockville.

He had been a partner in the firm of Galblum and Suyehiro since 1960. Over the years, the firm had offices in Washington, Chevy Chase, Hillcrest Heights, Potomac, Waldorf, Upper Marlboro and Fort Washington.

Dr. Suyehiro had served on the faculty of the Howard University dental school since the early 1970s, and was an assistant professor of orthodontics at the time of his death. He also had lectured in Germany, Italy and Austria, and served on the staff at Children's Hospital.

He had been program chairman of the Angle Society, an international orthodontics organization, and was a fellow of the American College of Dentists. Other professional memberships included the Middle Atlantic Society of Orthodontists, the D.C. Dental Society, the Southern Maryland Dental Association, the American Society of Esthetic Dentistry and the Maimonidies Dental Society.

He served on the East Asian Advisory Council of the U.S.-Asia Institute during the Carter administration.

Dr. Suyehiro was a native of Los Angeles. He and his family were interned, along with many other Americans of Japanese descent, during World War II. He served in the Army during the Korean conflict. He was a graduate of the University of Southern California, and came to Washington in 1954. Four years later, he graduated from Howard University's dental school.

His hobbies included wine collecting, and over the years he collected a cellar of more than 10,000 bottles.

Survivors include his wife, Masako, and two daughters, Denise and Aimee, all of Rockville; his father, Torao, of Los Angeles, and two sisters, Kay Kuge, of Las Vegas, and Faye Inouye of Los Angeles.