It's estimated that more than half a million people in the UK have a significant facial disfigurement, according to the charity Changing Faces.
Whether it's a birthmark, congenital condition, or a disfigurement caused by injury or disease, you can be treated by the NHS after a referral from your GP.
While medical treatment can help to make a disfigurement less noticeable, the treatment's success depends on the nature of the condition, and it's rarely possible to remove it completely.
Psychologists warn that if you believe surgery will solve everything, you are likely to avoid ever accepting yourself fully, and this will affect your emotional wellbeing.
Saving Faces: The Facial Surgery Research Foundation is dedicated to improving research into the treatment of all forms of facial disfigurement.
The UK charity has surgeons and researchers throughout the country collaborating to work out which treatments offer the best results.
Founder Iain Hutchison, a consultant oral and maxillofacial surgeon, says clinical trials on facial surgery aren't like testing a new drug.
"The surgery is irreversible, whereas the effects of a drug wear off," he says. "There's been no randomised study to compare the efficacy of different types of facial surgery.
"The type of treatment offered depends on the individual surgeon. Our research aims to identify what works best."
Iain Hutchison, who works at the Barts and The London hospitals, sees the difference surgery makes to his patients.
"It allows them to fulfil their intellectual and psychological potential," he says. "Not only do they see themselves differently, but so does the rest of society."
Former patient Sue Morgan-Elphick says facial surgery has allowed her to come out of her shell and show her true personality. Until she had surgery at the age of 28 to correct a bone disorder, which had left her with a crescent-moon-shaped face, she had always kept her true self hidden.
She describes the surgery as a rebirth. "My natural cheeriness, which had been locked in all those years, suddenly burst out," says the nurse from Barrow-in-Furness.
Iain Hutchison became interested in facial surgery while attending to patients in casualty, working on "people whose lives had been shattered in a moment in a road accident," he says.
"Facial surgery is challenging, not only because of its intricacy, but because it has a profound effect on the patient's mind. I love the fact I deal not only with bones and soft tissue, but also with human emotions."
Iain Hutchison has set up an artist-in-residence in his facial surgery department. Portrait artist Mark Gilbert paints patients before, during and after surgery.
"The great thing about Mark's pictures [pictured above] is that in them the patients are in control. They're saying: 'I am not a victim. I can survive this cancer, or this attack with a baseball bat.' It's a kind of catharsis - a turning point for them."
An exhibition featuring the portraits of 30 patients was launched in 2000 at the National Portrait Gallery and has since toured the UK, Europe and the US.
One of the most striking works is a series of paintings of barrister Henry de Lotbiniere, who lost an eye and underwent 15 operations over 13 years, as surgeons chased the spread of cancer of the salivary gland.
Iain Hutchison says that, while there are obvious functional reasons for undergoing surgery, such as removing a tumour that might obstruct breathing, there are psychological reasons as well.
"It's valid to operate on a child if their disfigurement causes them to be severely emotionally disturbed," he says. "They're starting out in life. You want them to get the best chance."
"But there might not be the same urgency for someone in his 60s, who's happily married, has two children and still has all his physical and mental faculties."
Article provided by NHS Choices