Related Experiment Video
Updated: Jun 24, 2026
07:05
In Vitro Evaluation of The Effects Of Er,Cr:YSGG and Diode Lasers Used on Titanium Cylinder
Published on: June 6, 2025
Dentin microhardness and subsurface morphology after Er:YAG laser cavity preparation using different parameters.
Aline Evangelista Souza-Gabriel1, Michelle Alexandra Chinelatti, Jesus Djalma Pecora
1Department of Restorative Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, São Paulo, Brazil.
Journal of Dentistry for Children (Chicago, Ill.)
|April 4, 2009
Summary
The Er:YAG laser, particularly at 250 mJ/4 Hz and 350 mJ/4 Hz, enhances dentin microhardness up to 60 micrometers deep. Lower laser parameters yielded results comparable to traditional bur preparation.
Area of Science:
- Dental materials science
- Laser dentistry
- Biomaterials engineering
Background:
- Dentin microhardness is crucial for restorative procedures.
- Understanding laser-tissue interactions is key for optimizing dental treatments.
- Er:YAG lasers offer precise ablation but require parameter optimization.
Purpose of the Study:
- To investigate the impact of Er:YAG laser parameters on dentin microhardness.
- To analyze subsurface morphological changes induced by Er:YAG laser irradiation.
- To compare laser preparation with conventional bur preparation.
Main Methods:
- 130 dentin fragments were divided into 13 groups (12 laser, 1 control bur).
- Laser parameters varied in energy (200-350 mJ) and pulse repetition rate (2-4 Hz).
- Microhardness tested at 5 depths; subsurface morphology examined via SEM.
Main Results:
- Highest microhardness observed with 250 mJ/4 Hz and 350 mJ/4 Hz in deep dentin (up to 60 microm).
- Morphological changes varied with parameters, affecting depths up to 30 microm.
- Bur preparation resulted in lowest microhardness, similar to low-power laser settings.
Conclusions:
- Er:YAG laser settings of 250 mJ/4 Hz and 350 mJ/4 Hz effectively increase dentin microhardness.
- Lower Er:YAG laser parameters (e.g., 200-300 mJ/2 Hz) produce outcomes similar to bur preparation.
- Parameter selection is critical for achieving desired microhardness and minimal morphological alteration.
