This is a lot more difficult to assess. Judging a dentist by his formal training is a bit like walking into a food centre and choosing a stall where the hawker had formal training in cooking char kway teow or beef noodles. One does not need much formal training to be good at implants or dentures. Some Division 2 (non-graduate) dentists (with little formal training) who run their own laboratories can make dentures which are superior to those done by graduate dentists. It does not mean that the more courses a dentist has attended, the better his skills will be.
Sometimes, even formal training does not equip one with the skills needed to deal with clinical situations. Someone who has successfully placed 500 implants in clinical practice is quite undoubtedly more skillful than a new graduate from a 2-year, highly structured and academic formal training course. The latter will have a piece of certification. The former will not.
If I need an extraction, the most reliable place to get information is the neighbourhood coffeeshop. Ask the folks there who is good at extractions. The majority can’t be wrong. If I need dentures, I’d go to a Division 2 clinic with its own inhouse lab. If I want implants, I don’t just go to any oral surgeon but someone who is not always keen on implants.