Wait and see? SERIOUSLY?

A couple of days ago I got a phone call from my new, theatre-geek-dentist's office, reminding me that I had an appointment Monday morning.  Whaaa?  Oh, right!  I do remember something about that.  Lucky for me, I wasn't working this Monday (like I have been every other Monday for the last couple months) and so took me and Anya over for a little dental fun.

I haven't had x-rays in years.  Like 10 of them.  Or more.  It still kinda sucks, with the big thing you have to bite on that digs into your palette and the unnatural way you have to hold yourself, but it wasn't too evil.  "Have you ever broken your jaw?" The perky hygienist asked.
"Um, no."
"No trauma to the right side of your face?"
"Not that I can recall."  As though I'd, you know, maybe forgotten getting hit by a bouncer or flying judo chop or something.
"Hmmm." She kept shooting.
"What?"
"Oh, it's probably nothing."
"You're going to show me this nothing." I insisted.

So she did.  She pulled up the picture of the left side of my face and showed me what a normal x-ray looked like, and then showed me the right.  Very clearly, there was a big, shadowy white blotch under the roots of a couple teeth.  "What the hell is that?" I asked, happy that Anya was being read to by another staff member so she couldn't hear the small note of worry in my voice.
"Normally, that's what scarring looks like.  But if you've had no trauma, it's something else."
"Like what?" I squeaked.
"Oh, we'll have the dentist take a look."

Nice deflection, lady.

So he did.  He looked.  And he rummaged around in my mouth a bit before declaring that sometimes people get these bone spur thingies and that could be what it is.  "I've seen them as big as marbles!" he exclaimed, looking way too excited about the prospect of a massive growth in my face.  "For now, we'll just wait and see."
"So you think that's what it is?"
"Could be.  Could be nothing."

So let me see if I have this straight: there's a mass in my face and you don't know what it is?  And the solution here is to "wait and see"?

Why am I not comforted?

Anyone out there with a medical background want to just tell me it's not cancer.  I'll totally believe you.  Because right now?  Kinda feeling like a crazy person inside.