Q. My daughter is going for dental surgery on August 6th to remove her wisdom teeth before she goes away  at the end of August to seminary  (G-d willing) .  She has been working in the country for the summer but came in yesterday so I made sure that she had her dentist appointment and cleaning before the surgery. 
Unfortunately, she has a cavity which he says needs to be done before the surgery and he could only book her next Thursday, which is Tisha B’Av.  Is this a problem? Does it matter if she does it in the afternoon or the morning?
A. Horav Shlomo Miller’s Shlit’a opinion is that in need, if there is no other day available, she may take care of her cavity during Tisha Beav. It is better to do so in the afternoon after chatzos.
She should also be careful when rinsing her mouth not to swallow any of the water.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a