Effects of dentin age and bonding on microgap formation

Area of Science:

• Dental Materials Science
• Geriatric Dentistry
• Adhesive Dentistry

Background:

• Dentin adhesives are crucial for dental restorations.
• The effectiveness of dentin adhesives may vary with patient age.
• Understanding age-related differences in dentin bonding is essential for clinical success.

Purpose of the Study:

• To compare the effectiveness of two dentin adhesives in younger versus older human molars.
• To evaluate microgap formation in relation to dentin age and bonding agent type.
• To determine if smear layer removal influences adhesive performance in different age groups.

Main Methods:

• Extracted human molars from younger (16-26) and older (58-87) adults were used.
• Standardized cylindrical preparations were restored with one of two dentin bonding systems.
• One system adhered to the smear layer; the other removed it before bonding.
• Microgap dimensions (length and extent) were quantified using microscopy.

Main Results:

• A dentin bonding system that removed the smear layer resulted in significantly smaller microgaps in older dentin (P < 0.05).
• This smear layer-removing system also produced shorter microgaps in older dentin compared to younger dentin.
• No significant difference in the percentage of gap-free margins was observed between age groups.

Conclusions:

• Smear layer removal enhances the performance of dentin bonding systems in older individuals.
• Age-related changes in dentin may influence the efficacy of different adhesive strategies.
• Optimizing dentin adhesive selection based on patient age could improve restoration longevity.