My 5 y.o. has a dentist appt next week & I just assumed he wouldn't need x-rays yet. But, our friends' son just had his 2nd set today!?!?!? Is it common/mandatory to get x-rays at age 5? He still has all of his baby teeth.
It certainly isn't mandatory but it is common. You can just decline and they will tell you their reasons for wanting to take them. My ds got x-rays at age 3 because he had many cavities and we wanted to know the extent of the decay. Last time (age 4.5), I told the dentist that I didn't want x-rays for that visit but we will do them next time to check up on his supernumery tooth that needs extracting (the first x-ray caught the fact that he has an extra adult tooth).
You have the right to accept or refuse treatment. My son saw the dentist from the time he was three but didn't get an xray until he was six or seven and there were concerns about tooth alignment. Some dentists really want to xray them every time but you can always say no. You will also need to make a decision about topical flouride and maybe about sealants.
My 4 yo had x rays done at her last appt. They tried the appt before, but she wasn't able to tolerate it. I think they wanted hers especially because she had an accident and her 2 front teeth were injured. And she sucks her thumb.