Dentist for 11 mo?

I'm a ftm. Another mom I was talking to said she took her 1 yo to the dentist and had 2 cavities from breastfeeding the night. Because there is sugar in breastmilk. They were small cavities but her lo has to be put asleep with laughing gas and have silver caps placed on her teeth!! Is this too much? I'm terrified now. My lo might have more  cavities too since I breastfed her through the night. I am making her a dentis appt asap but if they tell me anything of the sort can I deny the caps? I feel like silver caps are way too much for 2 small cavities.