From: Mark Dreyer
To: ROOTS
Sent: Friday, August 25, 2006 2:08 AM
Subject: [roots] Cracked tooth saga continues

It seems like lately this particular referral source sends me nothing but cracked teeth.
I'm going to consults first from now on with this doc.

The probing defect was actually only 5mm.  I was pushing too hard and bent

the plastic probe making it look in the photo like a 7mm defect.

Would anyone have recommended tx on this tooth?  I didn't see the crack extending across the chamber floor,
but with it including the mesial marginal ridge and distal marginal ridge, I felt it was a lost cause,
absence of deep probing defect notwithstanding.

I'm getting SO tired of these cracked teeth.  I can see why endodontists are jumping on the implant bandwagon.
- Mark Dreyer



Teach that guy to diagnose the cracks himself so he treat them when it is still a restorative issue ;-).
The first thing he needs to be able to see are crappy, failing alloys.  Then he can hit them with some methylene blue
and then pop on some loupes for an aha! moment.  After two of these you can skip the methylene blue and just get
right to it - Arturo

Mark: have you been seeing a lot of these kinds of cracked cases, or have you just been seeing a lot of them from
this one referrer? - gary

Both - Mark

Mark, why do you think these teeth crack?  I'm absolutely convinced after looking at them for nearly forty years that
expansion of alloy is a major factor.  Of course occlusion is a factor also.  Guy

Guy, I'm just as convinced that resins crack teeth.  Here's one from this morning.

Actually I'm just joking on the resin thing, but the point is I can disprove your anecdote with one of my own.
I suspect that occlusion plays more of a role here than choice of restorative material - Mark



I KNOW resin will snap off a cusp or two cusps.  I've watched it happen under magnification.  I've actually heard a couple.
When it shrinks it cracks the cusp off if it thin.  I wonder what happens with a cusp of normal thickness.  It could crack
that if the tooth was brittle enough.  Guy