Structural and Morphological Changes in Human Dentin after Ablative and Subablative Er:YAG Laser Irradiation.

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Laser Dentistry

Background:

• Investigated the impact of Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) laser on dentin cavity wall properties.
• Focused on microhardness, chemical composition, and subsurface morphology.

Purpose of the Study:

• To evaluate the effectiveness of Er:YAG laser in preparing dental cavities.
• To compare laser-prepared cavities with those made by a high-speed handpiece.
• To assess the influence of subablative laser irradiation on dentin properties.

Main Methods:

• Forty human premolars were used, divided into four groups.
• Cavities were prepared using Er:YAG laser or high-speed handpiece.
• Specimens underwent either ablative or ablative plus subablative laser irradiation.
• Microhardness and SEM-EDS analysis were performed.

Main Results:

• Er:YAG laser preparation significantly increased dentin microhardness compared to bur preparation.
• Cavities prepared with Er:YAG laser showed significantly higher calcium ion content.
• Subablative irradiation showed a positive trend in improving microhardness and calcium content, though not statistically significant.

Conclusions:

• Er:YAG laser cavity preparation enhances mechanical and compositional properties of dentin.
• The combination of ablative and subablative laser irradiation shows potential.
• Er:YAG laser is a viable alternative to conventional drilling for cavity preparation.