while serving with the Marines in France, LTJG Alexander Lyle with the 5th Marine Regiment and LTJG Weedon Osborne posthumously with the 6th Marine Regiment during the advance on Bourches, France. The memory of LTJG Osborne lives on today with an annual award given in his name to the junior dental officer who exemplifies the qualities of high character, superior leadership, and devotion to duty. Navy Dental School Early in 1922, a significant milestone occurred: the creation of a Dental Division in the Bureau of Medicine and Surgery. Shortly after on 3 February 1923, the U.S. Naval Dental School opened as the dental department of the United States Naval Medical School. Its purpose was to furnish postgraduate instruction in dental medicine to officers of the Dental Corps of the Navy and to train and equip men of the Hospital Corps as assistants to dental officers. There were 150 dental officers on duty at the time. Expansion of dental practice In 1927, Navy Regulations authorized dental treatment to the officers and men on the retired list; before that, only enlisted were treated. During this era, Navy Dentistry began to focus heavily on prevention of disease, which was unique at the time and is now a quality that distinguishes the Corps today. Navy dentists demonstrated their skills throughout the 1920s and 1930s in Navy and Marine operations in places like Haiti, Nicaragua, and China. By 1939, 255 dental officers served at 22 major dental facilities ashore and afloat. Among them was the hospital ship . World War II Two Dental Corps officers were killed and four were wounded in the attack on Pearl Harbor in 1941; they would not be the last dental officers to die in the line of duty. As the US got ready for world conflict, Navy Dentistry's active duty numbers swelled to its highest levels ever – ultimately reaching 7,000 dental officers and 11,000 dental technicians. Active in nearly every engagement during the war, dental personnel who were assigned to operational units in the South Pacific often assisted in emergency medical operations ashore, especially facial trauma requiring surgery. Numerous dental officers were killed in action aboard war ships and in major battles in Guadalcanal, Tarawa, Saipan, and Iwo Jima. For their heroic efforts, 93 dental officers received personal awards, including the Silver Star, the Legion of Merit, the Navy and Marine Corps Medal, and the Bronze Star Medal.