At sharp end of surgeon's blade

He is disembodied, lifeless, eerie. A floating head with waxy, grey skin and that shock of hair, suspended in a specimen jar filled to the brim with preserving fluid, tucked out of sight to visitors to the Surgeons' Hall Museum for fear it may cause distress.

For as severed heads go, this one is even more disturbing than most others might be.

"You're not too squeamish, are you?" asks Chris Henry, heritage manager at the Royal College of Surgeons Edinburgh museum, as he prepares to unveil the reason why meticulously sketched images of the face and head of this unfortunate middle aged man are among the most striking features of a forthcoming exhibition.

For where flesh and bone should be on the left side of the face is a broad, gaping hole stretching from eye to ear to chin, the flesh gnawed away by a rampant tumour that, if it occurred today, could probably be tackled by medical expertise and its damage rectified by the reconstructive art of the plastic surgeon.

"That's one of the things we're trying to get people to think about," says Chris, who has delved into the hundreds of the museum's specimens in preparation for what promises to be a fascinating exhibition themed around plastic surgery, Skin Deep.

"It's about encouraging people to think about what is perceived as being 'acceptable' in the pursuit of beauty.

"It's not just to do with plastic surgery," he stresses.

"We want people to think about those who are born with facial disfigurements or who go on to develop them, and to consider what people might use plastic surgery for today.

"We want to show that plastic surgery isn't anything new."

The severed head, thought to date from before 1825 and an original specimen from the museum founder Charles Bell's collection, will remain behind the scenes for the exhibition.

Drawings of it specially commissioned for the event are graphic enough.

Visitors to what promises to be a fascinating exploration of the impact the surgeon's knife has had on rebuilding shattered features, of social attitudes to facial deformities and the modern quest for perfection - all themes tackled under the Skin Deep banner - will be greeted by an intriguing collection of sometimes curious and often grim exhibits.

Few are more bizarre than the brass mask currently waiting to go on display.It's been designed to cover the lower half of a man's face, with an oval flap that opens outward like a trap door to allow him to eat.

Inside, there's a lower set of teeth, a drainage system for saliva and assorted simple straps to hold it all in place.

Oddly, it also sports a rather dashing twirled brown hair moustache.

Next to it is propped a white cast of how its wearer, Alphonse Louis, would have looked in life: lower jaw blown away by artillery shrapnel and, with nothing to hold it in place, fat tongue lolling out.

The impact in white plaster is dramatic enough. In reality French soldier Alphonse, 22 years old when he was injured during the Siege of Antwerp in December 1832, must have been an arresting sight.

"He lost most of his lower jaw and his right forearm," explains Chris. "Many people will have heard of the film, The Man in the Iron Mask, Well this is the real thing.

"Alphonse was said to have been even more proud of his mask than the Legion of Honour and Leopold medals that hung on his tunic."

Records suggest that a cleverly wrapped scarf meant few who passed Alphonse in the street even realised that underneath was a gaping hole where the flesh and bone should have been.

It's those connections between patient, reconstructive surgeon, social reactions to facial deformities and different cultures' definition of what constitutes 'beauty' that curator Chris hopes the exhibition, supported by facial disfigurement charity Changing Faces, will highlight.

Such the black and white photograph of a middle aged man, two long curved cutaneous horns - dead keratin which erupt through the skin often as the result of a virus - sprouting from his forehead like antlers.

His deformity was far from deliberate. Yet some cultures revere what makes others reel in horror. Such as the man's mis-shapen skull, deliberately flat at the top and moulded at the sides during childhood to create the slight cone shape regarded by South American Mayan tribes as physical perfection.

Striking too are disturbing 1920s images of men whose facial features have been ripped apart by dreadful accidents, being gradually rebuilt by the emerging skills of plastic surgeons.

That era of medical advances led by the discovery of antibiotics, the growth of antiseptics plus two world wars providing human "guinea pigs" to perfect skills on, meant a period of rapid growth in the history of plastic surgery led by London based Sir Harold Gillies.

He is known as the "Father of Plastic Surgery", however, as Chris explains, the plastic surgeon's work stretches much further back than that.

"People were replacing noses in India as far back as 600 BC," adds Chris.

"It was an extreme punishment to have your nose cut off."Someone found you could grow a flap of skin from the arm to the nose - effectively building a new nose.

"There are Italian records of nose replacement using skin from the arm dating back to 1597, he adds.

"In 1794, two English surgeons in India watched a brickmaker perform a rhinoplasty on someone who had his nose cut off.

"They realised what a fantastic thing it was and the idea was eventually published in the Gentleman's Magazine."

By 1818, a German surgeon had published a book detailing his "nose job" techniques, entitled Rhinoplastik, and the word "plastic" stuck.

The first facelift, around the turn of the 20th century, was a forerunner to today's booming cosmetic surgery industry: the latest statistics from British Association of Aesthetic Plastic Surgeons (BAAPS) show the number of surgical procedures last year exceeded 36,400, an increase of 6.7 per cent from 2008, with more men than ever before turning to the knife to improve their looks.

"The face is such an important communication tool," adds Chris. "But there's this whole ethical minefield about what people should or should not do in the name of 'beauty'.

"These days many people want to have surgery to remove lines or give them a better figure, but in places in the Third World there are people desperate for surgery for cleft lips and others here have facial deformities," he says. "We want people to see the exhibition and think about it."

• Skin Deep: The Restoration of Form and Function, runs from August 5 at the Surgeons' Hall Museums at the Royal College of Surgeons Edinburgh. www.museum.rcsed.ac.uk

'IF YOU'RE NOT CONFIDENT, SURGERY WON'T HELP'

Susan Campbell Duncan is used to people staring at her.

"The other day I was on a bus when a white van drew up alongside," she recalls. "One guy was having a good look at me.

"He turned to his mate, who then leaned forward to look too. I thought, 'You have no idea what I've gone through to reach this point'."

She's lived with facial deformity since developing a rare form of facial cancer as a baby. Aged two, Susan underwent her first of almost 100 operations aimed at rebuilding her features.

Now 46, she says she's not going under the knife again. "More surgery is not going to do very much good," she shrugs.

Susan, who lives in Craigleith, works with Changing Faces, a nationwide group that supports people with facial disfigurements and is supporting the Surgeon's Hall exhibition.

For her, there are clear lines between the kind of surgery she's undergone, and surgery carried out in pursuit of perfection.

"I understand some people who have cosmetic surgery because they want to look beautiful, but if you're not already confident, no amount of cosmetic surgery will change it," she says.

"People might look at me and think 'how can she possibly be happy', but I am. I said a long time ago that 'okay, this is what I have got to live with, I can't change it'."