Hi folks: I dont know how many of you get ESOLA but in the Spring 2007 issue Dr. Giovanni Oliva and Maria Genovese ( I believe its his wife) from Rome wrote a really great article on the ” Effect of Er:YAG Laser Parameters on Enamel: SEM Observations.”

In this article the conclusion was something I have been preaching for many years now on how to improve the bond strength on enamel using the laser….

I quote from the conclusion…..

“This study confirms the possibility of performing ablation within defined limits, forming microcavities with a finely etched and rough surface that are well prepared for treatment with adhesive restorative materials. For best treatments, it is recommended to use lower levels of energy emitted at a higher repetition rate.”

In the study he compared both the Delight (contact) and I believe a Kavo Key 3 laser (non contact ) with both high and low pulses and high and low energy.

There was SEM evidence of induced alterations in both lasers at the high energy settings (MJ) with microcracks, melting and flakes. This leads of course to poorer bonding and is something we must be concerned with.

It is absolutely imperative that you either go back over your enamel bevels at low mj and high rep rate or scrape, air abrade or use a bur to remove this layer to get a bond that wont leak.

Ask me how I know.

Many many of the research articles use power settings that give microleakage and just because it is enamel doesnt mean that you must use high enamel settings. For your bevels you must keep the Hz high and mj low.

Dr. Olivi is someone who I saw again at the ALD meeting ( it was good this year even though I was only there for 2 days), and he is very knowledgeable has gorgeous slides (both SEM and regular scope photos) and his articles are clinically based.

Hope that you get a chance to read this one….it was well done.

Cheers

Glenn