Dr. Grossman has been in private practice for 30 years on Long Island in New York. He is a member of the federal disaster team DMORT (Federal Disaster Mortuary Operational Response Team), the FBI's InfraGardProgram, the Nassau County Medical Reserve Corps, the American Academy of Forensic Sciences and the American Society of Forensic Odontology.

He is a graduate of New York University College of Dentistry, and he also graduated from the FBI's Citizen's Academy. He has lectured at the Greater New York Dental Meeting as well as at Yankee Dental Conference and the Nassau County Dental Society.