Fracture Toughness of CAD/CAM Resin-Based Materials vs. Direct Composite Resins: A Scoping Review
Source abstract
Abstract
Objective: To compare the fracture toughness of CAD/CAM resin-based restorative materials and direct composite resins. Materials and Methods: A systematic search was conducted in July 2025 across PubMed/MEDLINE, EBSCO, Scopus, ISI Web of Science, and grey literature. Eligible studies were only in vitro investigations evaluating fracture toughness of direct composite resins and CAD/CAM hybrid materials. Study selection, data extraction, and risk-of-bias assessment were performed independently by two reviewers. A systematic review and meta-analysis were not performed due to methodological heterogeneity, and findings were synthesized qualitatively. Results: Fifty-two studies met the inclusion criteria, including 16 assessing CAD/CAM restorative materials. Considerable variability in fracture toughness values was observed, even within the same material type. Most studies were judged to present a medium risk of bias. Short fiber-reinforced composites exhibited higher fracture toughness, whereas other CAD/CAM resin-based materials showed values comparable to direct composites. Conclusions: Current evidence does not confirm superior fracture toughness of CAD/CAM resin-based materials compared with direct composites. Short fiber-reinforced composites appear to offer improved resistance to crack propagation. Standardized testing protocols are needed to enable more reliable comparisons.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Dental materials and restorations · Endodontics and Root Canal Treatments · Dental Health and Care Utilization
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Operative Dentistry, School of Health Sciences, National and Kapodistrian University of Athens, 11527 Athens, Greece
Certified Systemic Management Program (CSAP), University of Piraeus, 18534 Piraeus, Greece
References (100+)
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