My dentist has some pretty crummy chairs in the waiting room. This certainly affects my visits to the dentist. My dentist is not in the furniture business. My dentist also has a crappy website. He is not in the software business.
Does your dentist have receptionist who takes care of appointments and generally treats you nicely while you wait? He's in the customer service business.
Does your dentist have his diplomas, fellowships, and awards on his shelf? He's in the marketing business.
Does your dentist work on your teeth and makes you suffer and withstand amazing pains? He's in the dentistry business.
Does your dentist have a website? He's in the software business, regardless of if the website is a simple website so you can find his phone number or if the website provides a way to check your appointment date (or some other service).