He is the past President of American Association of Orthodontists. Doctor Mershon helped organize First International Orthodontic Congress in 1926 and served as its honorary president He obtained his dental degree from Pennsylvania College of Dental Surgery in 1889.
He served as a faculty at the school for many years and also practice as a private dentist in the area.
He then attended Angle School of Orthodontia in 1908 and then became one of the first orthodontist in eastern Pennsylvania. He also served as Head of Orthodontics at the University of Pennsylvania from From 1916 to 1925.
He served as President of American Association of Orthodontists, the Northeastern Society of Orthodontists, the Philadelphia Orthodontic Society where he was their first President, and the Philadelphia Academy of Stomatology. He also developed the Removable lingual arch Appliance.
In honor of Doctor Mershon, in 1960 American Association of Orthodontists established an annual series of lectures.
Doctor Mershon was credited in organizing short refresher and extension courses for the members of the dental societies.