Does etching time affect the in vitro performance of a sealant material?

Area of Science:

• Dentistry
• Dental Materials Science

Background:

• Fissure sealants are crucial for preventing dental caries.
• Enamel etching is a critical step for sealant adhesion.
• Variations in enamel structure (prismatic vs. aprismatic) may influence etching efficacy.

Purpose of the Study:

• To evaluate the effect of different etching times (15-60s) on shear bond strength (SBS), failure modes, and microleakage of fissure sealants.
• To compare the outcomes on both aprismatic and prismatic enamel types.

Main Methods:

• In vitro study utilizing 96 human third molars.
• Teeth were divided into groups based on enamel type (prismatic/aprismatic) and etching time (15, 30, 45, 60 seconds).
• Shear bond strength, failure mode, and microleakage were assessed after 5,000 thermocycles.

Main Results:

• Increased etching time significantly enhanced SBS on aprismatic enamel, with 60 seconds showing the highest values.
• Microleakage was minimal across all tested groups.
• While 60 seconds yielded the best SBS, the differences between 30 and 60 seconds were marginal.

Conclusions:

• Optimal etching time for fissure sealants on aprismatic enamel is approximately 60 seconds for maximal SBS.
• A 30-second etching time appears clinically justifiable, offering a favorable balance between bond strength and procedural efficiency.