I had a dental cleaning and exam earlier this month. Dentist and hygienist both wearing face shields over their masks, and with huge heavy gowns. Same routine when I went to the endodontist later in the month for a checkup on some work he did last year. And of course, measuring my temperature and not letting me in until they were ready to go. The receptionist at the endodontist gave me a pen to fill out a form and told me to keep it. They were giving separate, previously unused pens to each patient.
You won’t get perfect safety, no matter what they do, but they’re doing their best. And doing their best to assure you that they’re doing their best. Decide for yourself whether you want to “risk” it.