In order for a physician to be a plastic surgeon, one must complete an approved Residency training program in Plastic Surgery. Plastic surgery involves a spectrum of different components, including cranio-facial surgery (e.g. cleft lip or palate), burn surgery, hand/microsurgery, maxillo-facial trauma, general and breast reconstructive surgery, and cosmetic surgery (facelift, tummy tuck, liposuction, etc.). Because the field of plastic surgery is so broad and extensive, the training required to become a plastic surgeon is between 6-8 years after medical school.
Some plastic surgeons, especially in more rural areas, offer the full spectrum of plastic surgery, but most tend to specialize - i.e. - tailor their practice with greater emphasis on one or two areas of plastic surgery. But whether a plastic surgeon chooses to specialize in hand surgery or cosmetic surgery, they are still "plastic surgeons" as deemed by the American Board of Medical Specialities (ABMS).
In reality, any licensed physician can offer cosmetic services, as this is not illegal. The term "cosmetic surgery" is not a recognized discipline by the American Board of Medical Specialities, i.e. - there is no Board Certification by ABMS in Cosmetic Surgery. There are numerous opportunities to "train" in cosmetic surgery (usually 6 months to 1 year) - but none leading to a board certification by ABMS. So if someone is a "cosmetic surgeon" - s/he could be an ENT surgeon, a Dermatologist, a General Surgeon, an Opthalmologist, a General Practioner, or a Plastic Surgeon.
This may come as a bit of shock for most people, as many people equate plastic surgery with cosmetic surgery. As a plastic surgeon specializing in cosmetic surgery, I do not pass any judgement on physicians of different disciplines practicing cosmetic surgery, as long as they are well trained and honest about their credentials (as I would expect of plastic surgeons as well). I do have a problem with cosmetic surgeons misleading patients into thinking that they are plastic surgeons, taking advantage of the common misconception that public has about synonymity of plastic surgery with cosmetic surgery.
Finally, there are a multitude of terms out there, including facial plastic surgery, oculo-plastic surgery, etc. These terms are often coined by ENT surgeons (for facial plastic surgery) and opthalmologists (for oculo-plastic surgery), as they often represent further training of the aforementioned disciplines, i.e. an ENT may extend their training in plastic surgery of the face. These training opportunities are usually offered only to certain disciplines (e.g. an oculo-plastic surgery fellowship is offered to only opthalmologists).
Bottom line: Ask questions about your doctor's credentials, training, and board certification. There are many confusing terms, all trying to denote some degree of extra expertise or specialty, but at times it's misleading - whether it'd be intentional or unintentional.
