"There is a strange fascination with these (WAV) threads. It's like putting your tongue into an aching tooth - you know you'll regret it but you do it just the same" (S&R)...I'm a 100% sure, Stu!, that my tooth-aches (and it's been a while) have derived from leaving bits of food in the gaps; accordingly, when we get one, we simply make sure the area is now clear, and keep tongue and all away from the trauma.