Amir Khan,
Piyush Singhal,
- Ph.D. Scholar, Department of Mechanical Engineering, GLA University, Mathura, Uttar Pradesh, India
- Professor, Department of Mechanical Engineering, GLA University, Mathura, Uttar Pradesh, India
Abstract
Dental resin composites are widely used in restorative dentistry because of their excellent aesthetics, conservative cavity preparation, and satisfactory mechanical properties. However, their long-term clinical performance is limited by polymerization shrinkage, wear, microcrack formation, water absorption, and degradation in the oral environment. This study investigates the mechanical and morphological characteristics of Halloysite Nanotube (HNT)-reinforced Urethane Dimethacrylate (UDMA) dental composites to enhance the structural performance and durability of restorative materials. UDMA-based composites containing different concentrations of HNTs were fabricated using controlled mixing and light-curing techniques. Their flexural strength, flexural modulus, compressive strength, Vickers microhardness, and water sorption behavior were evaluated. Morphological characterizations were performed using Scanning Electron Microscopy (SEM). The experimental results demonstrated that low to moderate HNT loadings significantly improved the mechanical performance of the composites by enhancing stress transfer, crack deflection, and filler matrix interactions. Increased microhardness indicated superior surface durability and wear resistance. SEM observations revealed uniform nanotube dispersion at lower filler concentrations, whereas higher HNT loadings resulted in particle agglomeration, increased viscosity, and localized void formation, adversely affecting mechanical performance. The findings confirm that HNTs are effective nano reinforcements for UDMA dental composites when incorporated at optimized concentrations and uniformly dispersed within the resin matrix. The developed nanocomposites exhibit enhanced stiffness, hardness, and fracture resistance, demonstrating considerable potential for advanced restorative dentistry. Future investigations should focus on long-term aging, simulated oral wear, antibacterial performance, cytocompatibility, and clinical validation to establish their suitability for next-generation dental restorative applications.
Keywords: Halloysite nanotubes (HNTs), dental composites, restorative dentistry, mechanical characterization, scanning electron microscopy (SEM).
[This article belongs to Special Issue under section in Journal of Polymer & Composites (jopc)]
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Journal of Polymer & Composites
| Volume | 14 | |
| Special Issue | 04 | |
| Received | 17/08/2026 | |
| Accepted | 07/09/2026 | |
| Published | 20/09/2026 | |
| Publication Time | 34 Days |