After graduating from Canisius High School, he attended Canisius College where he earned his Bachelor of Science degree in Biology. Dr. Gengo earned his DDS from the University at Buffalo School of Dental Medicine, graduating magna cum laude. He was awarded the American Association of Endodontics Award, presented to a graduating student demonstrating the greatest ability and interest in the field of endodontics. Dr. Gengo was also awarded the Edwin C. Jauch Award which is presented to a graduating student who completed comprehensive cases reviewed by a panel of judges, who determine which of the cases is most outstanding.

Following graduation, Dr. Gengo began his endodontics residency at the University at Buffalo School of Dental Medicine. During his residency, he was awarded the Thomas J. Feidt Scholarship, awarded to a post-graduate student from the Western New York area. He completed his residency in 2015, earning his certificate in endodontics. In 2017, Dr. Gengo earned his most noteworthy accomplishment.  He became a Board Certified Diplomate of the American Board of Endodontics.  Board certification is achieved by less than 25% of endodontists in the United States.

For the last 7 years, Dr. Gengo has been practicing endodontics full-time in the Buffalo area.  He is also a Clinical Assistant Professor in the Department of Periodontics and Endodontics at the University at Buffalo School of Dental Medicine, teaching in the post-graduate endodontics clinic.

He is currently the president of the Fonzi Dental Study Club and is a member of the American Association of Endodontists, the American Board of Endodontics, the New York State Association of Endodontists, the Eighth District Dental Society, the New York State Dental Association and the American Dental Association.