Dentistry, mildly terrifying at the best of times, was a gruesome and brutal trade in the 19th century. There were no anaesthetics to ease the pain of extractions, no antibiotics to combat abcesses, little to reduce the mind-bending agony of root canal problems but brute force and implements that would not have been out of place in a medieval torture chamber. All that and the problem of dentures.

Before the synthesis of modern plastics and polymers, the best dentures were human teeth, often scavenged from corpses on the battlefield. In the years after Napoleon’s defeat in 1815, teeth harvested from the young soldiers who died at Waterloo became prized for their condition, so much so that they became the brand of distinction: Waterloo Dentures.

Waterloo Dentures is also the name of a film directed by Rachael Moriarty and Peter Murphy. It is a love story, epic in its sweep, a tale of high passion and low dentistry and one with a sinister twist in the tail.

The setting is Ireland, early in the 19th century. Clara loves Daniel: but he must prove himself by soldiering on the Continent. We cut to the battle of Waterloo: Daniel falls. Back home, Clara is pestered by an unwanted suitor — a man whose bad teeth previously made women swoon. When he arrives to show off his new dentures, Clara realises there is something ominously familiar about his teeth.

It’s a masterpiece of black comedy, its epic grandeur, memorable characterisation and sharp humour all the more remarkable because it is only three minutes long. Welcome to the world of the short-short film.

While the traditional short can take a leisurely 10 minutes to get to the point, the new wave of Irish short shorts, of which Waterloo Dentures is the best, have no such luxury. There is no room for wastage: the narrative must be refined and condensed in a way that makes every frame tell.

Short shorts are the result of an Irish Film Board scheme to reach a wider audience. There are no rules apart from duration: they must have a maximum length of three minutes. The latest batch, shown at the Galway Film Fleadh, includes films of every description: from a mini-epic such as Waterloo Dentures to brisk exercises in animation and teen angst.

Martin, by Imogen Murphy, tells the story of a young man who can no longer tolerate his parents. He vanishes, leaving a note in which he reveals his plan to live life as a badger. His bemused father wonders if he meant to say “cadger”, but then holes start to appear in the lawn overnight. It is clear that Martin meant what he said.

Both Martin and Waterloo Dentures are proof that a three-minute film can contain as much resonance as the longer form. In the case of Martin, a witty absurdist fable, it also hints at adolescent angst about bodily changes and extreme ideas. It gives a feral edge to the generation gap, sharply and quickly in images that are stripped of padding. And it makes its point in less time than the average feature film devotes to its opening credit sequence.

Superficially, one might think that time constraints cause film-makers to concentrate on action: that there is no room for resonance when the essentials have to be communicated with such brevity. In fact, the opposite proves to be the case.

Because of their abruptness, short shorts are more like ads than films: the effect is immediate.

But a short short is not necessarily a frantic blur of images: some are almost leisurely. One film, Lotus, is a computer animation with a meditative calm. Its images of opening flowers are reminiscent of the trippy psychedelic sequence from 2001: A Space Odyssey.

It is no coincidence that these short films seem to use some of the devices of advertising: they are expressly designed as adverts or trailers for Irish film.