Q. Hi yesterday I walked under a sign and stood up too quickly bashing my head on the metal pole and biting hard on my teeth. My lower teeth look like they have some fine lines (the left bottom has a 45 degree line at the top and the right line around the top down and up) and I seem to have a dull pain – I am terrified I have cracked them – all the dentists are away on holiday for 3 weeks – I am supposed to start my holiday but am beside myself