Restoring Class V Abfraction
Lesions
Retention of class V restorations can
be a real problem until you understand a little physics.
First of all, do you understand what an
abfraction lesion is? An abfraction is a notch in a tooth near the
gumline. It usually occurs in the cementum, and is very smooth. We told
our patients for years that these were caused by over-aggressive brushing.
But then in the 90's someone published a study where they had discovered
these lesions subgingivally, which seriously undermined the
toothbrush abrasion hypothesis. Further study showed that these were
stress-related lesions. They are caused by flexing of the teeth, and
while they usually occur on the facial aspects of teeth, they can also
occur on the lingual.
This brings us to the issue of retention.
Restorations of these lesions are the bane of adhesive technology. It will
be the first restoration to de-bond, and the ultimate test of any bonding
agent has been its effectiveness in one of these class V situations.
However, the flex stress theory of the cause of the abfraction lesion
leads naturally to the flex stress theory of retention of abfraction
restorations. It has been discovered that when the restorative material is
flexible, retention increases dramatically.
Hence, when you restore an abfraction
lesion, use a microfill. Microfills are less stiff, more flexible. In our
practice, after we discovered this connection and began using microfills
exclusively in abfraction situations, our failure rate decreased
dramatically. Here are some choices that work well for abfraction lesions:
-
Silux Plus. An
advantage of Silux Plus is that it is manufactured in several shades that
are quite dark and thus compatible with the root surface.
-
Renamel. Renamel is a
tough, esthetic material that takes a high shine and hold up well in class
V situations.
-
Heliomolar. With
Heliomolar you have a radiopaque option, which is helpful in case the
insurance company wants you to prove that you actually restored the tooth.
Click here to find
clinical dentistry books.
Click here to find
operative or restorative dentistry books.
More articles
America's Dental Bookstore maintains this collection of articles on dentistry submitted by visitors to our site. These
could be clinical tips, research articles, opinion articles, dental jokes, or
whatever. Do you have something you'd like to submit? If so,
click here to submit an article. |