Girls, we're almost three months in, and our teeth are starting to fal…

Girls, we're almost three months in, and our teeth are starting to fall out. Calgel helps, it worked well for my older child, but now something isn't helping my younger one. My husband's sister says it's better to give her ibuprofen than to apply calgel. She says that it damages the teeth, and because of these ointments, then bad teeth will come. Her friend's daughter didn't get anything applied, and the teeth are good. Well, she did well with it, but mine cries a lot, mainly applying at night, during the day tolerable. What do you think? Can ointments affect tooth quality?