how long is oral surgeon school
In Germany for instance, oral surgery training takes 3-4 years, depending on your school. Oral and Maxillofacial surgeons on the other hand, have to have a dental degree (4 - 5 years) + medical degree (6 year), then apply for the OMFS training, which is no less than 5 years. (many opt for additional 2 years in plastic surgery).
The minimum is usually 3-4 years, and it is usually 6 years for those who opt to do a combined M.D. + specialty training in OMFS. In the US, Maxillofacial surgeons have to do 4 years of dental school, then 4 or 6 years for OMFS, depending on the program (2 extra years in general surgery and med school).