The Dawson Academy has made light bulbs go off in the heads of dentists for decades. When Dr. Michael Verber first heard Pete Dawson’s Egg analogy from Dr. Leonard Hess, he felt inspired to film this video. With the help of Erickia Rynard and about 6 dozen eggs, he finally got it right.
From the work of Dr. Pete Dawson we know that there are some criteria to a stable occlusion.
Number one, we want the joints to be in centric relation, we want anterior guidance within the envelope of function and we also want posterior teeth that do not erupt.
Now, my friend and Mentor Dr. Lang Hess when he drew some sketches of an egg on an articulator, and since we’re so “eggstatic” about occlusion, what I thought we could do is demonstrate this live.
What we have here is an egg mounted in an articulator, and in case we break anything… We have a couple extra.
What we have here is the egg mounted into the arc. The egg represents the posterior teeth, the pin represents the anterior stop. The inverted tripod concept remains true as the condyles are fully seated.
The articulator is unlocked and I’ll represent the force of the contracting elevator muscles by pushing down on the articulator.
Now no matter how hard I push, the egg will remain intact.
In the next demonstration, we’re going to represent the egg out of CR. After we change out the plates and close the articulator, I want the anterior pin seated to represent the joints out of CR. Now when I apply the force that represents the elevator muscles contracting, let’s see what happens to our egg…
SCRAMBLED!
In the third example the egg is mounted in CR, but of course there are no anterior teeth, so there is no anterior guidance. The egg represents the posterior teeth. So we’re going to lock the anticulator and nothing is happening when I apply force, but what happens when I go into a lateral excursion.
So now we’ve switched out the plates to some that have anterior teeth, notice I have the pin raised because we have the teeth to represent the anterior stops. What happens now when we go into a lateral excursion? Well, with canine rise, the egg stays intact.
The other way posterior teeth rub is if we have poor or buly contours on a posterior tooth. Let’s say we do a crown and we replace the tooth with a restoration that’s larger and bulkier.
Of course, the egg’s going to break.