This is a difficult questions for me to answer, because I am not sure what conditions you might be talking about, and you don't give a lot of information in your question.
The most common 'head' conditions that are sometimes managed surgically are problems with the ears, nose, and throat. The doctors who manage these conditions are called otolaryngologists
. They treat a wide range of conditions. For example, these are the doctors who insert tubes into the ears of children with chronic ear infections. They also remove tonsils when that is necessary. They may also perform surgical work on the nose, for example if there is a deviated nasal septum or a nasal polyp that makes breathing difficult.
Of course plastic surgeons
also perform a lot of surgery on the head. This is, as you say, commonly for cosmetic reasons (such as work on the nose or lips or eye wrinkles). However, there is sometimes medically necessary plastic surgery on the head; the most common reason would be repairing a cleft lip or palate or reconstruction after trauma.
If you have questions about whether you need to see one of these types of specialists, you should talk to your primary care doctor
who can refer you.