Nanomechanical properties of dentin treated with a CO2 laser for potential caries inhibition

Stefan Habelitz; Daniel Fried; Charles Q. Le; John D. Featherstone

doi:10.1117/12.778796

27 February 2008 Nanomechanical properties of dentin treated with a CO₂ laser for potential caries inhibition

Stefan Habelitz, Daniel Fried, Charles Q. Le, John D. Featherstone

Proceedings Volume 6843, Lasers in Dentistry XIV; 684306 (2008) https://doi.org/10.1117/12.778796
Event: SPIE BiOS, 2008, San Jose, California, United States

Abstract

The effect of pulsed CO₂-laser treatments on the microstructure and nanomechanical properties was studied using atomic force microscopy and nanoindentation. The microstructure and roughness of dentin specimens treated by a 9.3 μm CO₂ laser at fluences of 0.5; 0.75; 1.0; and 1.5 J/cm² were evaluated and the elastic modulus and hardness before and after a nine days demin/remin application for laser treatments at 0.75 and 1.5 J/cm² were determined. The hypothesis that CO₂-laser-treatments reduce or inhibit the demineralization process was tested. Surface cracks were observed at fluences of 0.75 J/cm² and higher. Surface roughness increased strongly after laser irradiation and was about 10 times higher at maximum fluence. Mechanical properties profiles from the laser treated surface to sound dentin showed increased modulus and hardness values at dentin surfaces treated, indicating removal of organic phases and reinforcement of the tissue by increased mineral content. Mechanical properties decreased after demin/remin application in all groups and the hardened surface layer disappeared for samples treated at 0.75 J/cm². While increased properties were still observed in the laser affected surface zone for treatments at 1.5 J/cm², demineralization was severe underneath these layers as indicated by a sharp drop in properties. The depth of demineralization was slightly decreased in the laser-treated group compared to the untreated controls. We conclude that CO₂-laser treatments produce dentin surfaces with increased nanomechanical properties. These surface layers do not, however, provide protection against demineralization due to surface cracking and possible delamination. Moreover, the surface cracks induced by the laser-irradiation raise concerns about a clinical potential for caries inhibition in dentin.

Citation Download Citation

Stefan Habelitz, Daniel Fried, Charles Q. Le, and John D. Featherstone "Nanomechanical properties of dentin treated with a CO₂ laser for potential caries inhibition", Proc. SPIE 6843, Lasers in Dentistry XIV, 684306 (27 February 2008); https://doi.org/10.1117/12.778796

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available