Ron Hutchinson's new play Burning Issues is principally about the gap between private morality and public reputation. It concerns the discovery that a writer of unblemished international status has for years kept a journal packed with fetid bigotries, and it is largely taken up with the arguments over whether they should be published.
But the play is also about culture clashes: two of its protagonists are American and two British. And judging from the reaction on the first night, the point at which Hutchinson's probe really made contact with the audience's collective nerve was the scene in which a British editor, Neil, argues with his American colleague (and lover) Jessica.
"You are other. You are foreign," he complains as he confesses his irritation with her argument. "That accent and those flawless teeth are making it worse. Making my teeth ache, in fact."
"Are they teeth?" she replies. "I thought you were having something done about them."
"These are British teeth, the products of socialised dentistry," he replies indignantly, and at that point the audience lets rip.
There were bigger laughs later in the evening, but it was that line, I think, that loosened them up.
"Crumbling and stained though they are, they are a little part of my country's heritage," continues Neil. "Uncle Sam will never get his hands on them."
That struck me as a pretty good metaphor for one of the play's face-offs - between the gleaming, ruthless interventions of American corporate capitalism and the tarnished amateurism of old-fashioned British publishing. It also, incidentally, offered an explanation of something I had read a few days earlier, a newspaper report on the generally decrepit state of British dentistry. Perhaps it wasn't just consumer indifference that had brought us to this pass, but something more like patriotic pride.
Certainly the British have an ingrained suspicion of dentistry - particularly corrective dentistry - which is as much moral as it is fearful. When Martin Amis secured a large advance a few years ago, the fuss over the money was exacerbated by the revelation that he would be spending some of it on having his teeth fixed.
It was as if the desire for oral health exposed an essential frivolity in his character - a capitulation to American notions of what mattered. Give or take a few extractions, an Englishman lives and dies with the teeth he was born with.
I confess that I'm susceptible to this irrational prejudice myself. Why else would I have felt a surge of affection recently on seeing an enormous close-up of an American star and noticing that two of his front teeth (lower incisors) were slightly misaligned?
He suddenly seemed like one of us - and the feeling was oddly national. That tiny uncorrected snaggle announced a commitment to British dental authenticity that seemed as much an act of cultural sympathy as buying a house in the Boltons and putting his daughter down for Cheltenham Ladies College.
I think the prejudice flows from the fact that our teeth are felt to be a peculiarly candid part of our body - a kind of Picture of Dorian Gray that we keep concealed beneath the drapery of the lips. However much slap we put on outside, the teeth will tell the truth when they're eventually revealed - an appalling truth in many cases, with sins of commission and omission layered on the enamel.
And where Americans have no problem with making their teeth match their self-image - in using money to put right the deficiencies of nature - we somehow prefer to leave the basic architecture undisturbed, treasuring the eccentricities of our bite pattern. We won't betray our roots - no matter how curious or painful they may be.