Morphological Analysis of Dentin Surface after Conditioning with Two Different methods: Chemical and Mechanical

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Surface Science

Background:

• Improving resin restorative material adhesion to dentin is crucial in adhesive dentistry.
• Alternative dentin pretreatment strategies are continuously explored to enhance bonding.
• The smear layer formed during cavity preparation can impede adhesion.

Purpose of the Study:

• To evaluate airborne-particle abrasion (APA) with aluminum oxide for smear layer removal from dentin.
• To assess the effects of APA on dentin microstructure.
• To compare APA with phosphoric acid (PA) pretreatment.

Main Methods:

• Twenty human third molars were pretreated with either PA or APA (aluminum oxide).
• Dentin surfaces were analyzed using an environmental scanning electron microscope (ESEM) before and after pretreatment.
• Specimens were smear-covered before pretreatment.

Main Results:

• Phosphoric acid (PA) pretreatment opened and enlarged dentin tubule orifices, causing erosive effects.
• Airborne-particle abrasion (APA) exposed dentin tubule orifices without enlargement but induced crack-like alterations.
• APA successfully removed the smear layer from dentin surfaces.

Conclusions:

• Airborne-particle abrasion (APA) with aluminum oxide is effective in removing the smear layer.
• The microstructural alterations caused by APA require further investigation regarding their impact on adhesion and dentin integrity.
• Proper dentin conditioning is essential for successful adhesive dentistry outcomes.