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Quasistatic Mechanical Testing for Computer-Aided Design and Manufacturing Occlusal Veneers Cemented to Milled Dentin Analog Material
Published on: December 20, 2024
Four-point bending evaluation of dentin-composite interfaces with various stresses
Michal Staninec1, Harrison Nguyen, Paul Kim
1Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, CA 94143, USA. michal.staninec@ucsf.edu
Medicina Oral, Patologia Oral Y Cirugia Bucal
|January 3, 2008
Summary
Composite-dentin bonds show robust strength against simulated degradation. Thermal cycling, sodium hypochlorite (NaOCl) immersion, and mechanical fatigue did not compromise bond integrity in this study.
Area of Science:
- Dental Materials Science
- Biomaterials Engineering
- Composite Restorations
Background:
- Dental composite restorations rely on durable bonds to tooth structure (dentin).
- Understanding the long-term stability of these bonds under various environmental stresses is crucial for clinical success.
Purpose of the Study:
- To evaluate the fracture properties of composite-dentin beams bonded with self-etching adhesive.
- To assess the impact of simulated degradation mechanisms on bond strength.
Main Methods:
- Composite-dentin beams were fabricated and bonded using a self-etching adhesive.
- Beams underwent short-term pretreatments: thermal cycling, immersion in 5% sodium hypochlorite (NaOCl), or fatigue cycling (10^5 cycles).
- Four-point bending tests were conducted in Hanks' Balanced Salt Solution to determine fracture strength.
Main Results:
- Solid dentin and composite beams exhibited high bending strengths (approx. 164.5 MPa).
- Bonded beams demonstrated a mean strength of 56.3 MPa.
- Pretreatment conditions (thermal cycling, NaOCl immersion, fatigue cycling) did not significantly decrease the bond strength of the composite to dentin.
Conclusions:
- Self-etching adhesives provide durable bonds between composite and dentin.
- The tested degradation factors (thermal stress, NaOCl exposure, mechanical fatigue) do not appear to weaken the composite-dentin bond strength in the short term.
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