Do resin-modified 3D-printed complete dentures show improved mechanical, physical, surface, and biological properties? A systematic review and meta-analysis.

OBJECTIVES

To assess whether resin-modified 3D-printed denture base resins demonstrate improved mechanical, physical, surface, and biological properties compared to unmodified counterparts.

DATA

Meta-analyses were conducted using a random-effects model. The subgroup analyses explored sources of heterogeneity. Sensitivity analyses and publication bias assessments were performed using leave-one-out tests, funnel plots, and Egger's and Begg's tests. The methodological quality of included studies was appraised using the QUIN tools.

SOURCES

A systematic search was conducted across five electronic databases (PubMed, Embase, Scopus, Web of Science, and the Cochrane Library) and Google Scholar, as of January 2025.

STUDY SELECTION

Thirty-four in vitro studies comparing resin-modified and unmodified 3D-printed complete denture base materials were included.

RESULTS

Meta-analyses revealed that modified resins significantly increased fracture toughness, tensile strength, impact strength, elastic modulus, and microhardness (P<.05), while flexural strength was significantly decreased (WMD = -3.32 MPa; P<.001). No significant differences were observed for flexural modulus, compressive strength, nanohardness, or bulk hardness. For physical and surface properties, the contact angle was significantly reduced (WMD = -7.69°; P=.009), whereas other metrics showed no significant differences. Biologically, modified resins significantly reduced microbial counts, metabolic activity, and cell viability (P<.001).

CONCLUSIONS

Modifying 3D-printed denture base resins enhances several mechanical and biological characteristics, particularly impact strength and antimicrobial performance. However, a trade-off in flexural strength may occur. These findings support targeted resin modifications to improve the performance of 3D-printed complete dentures.

CLINICAL SIGNIFICANCE

The use of resin modification 3D-printed resins may enhance the clinical durability of complete dentures by increasing resistance to impact and reducing Candida colonization. However, the reduction in flexural strength suggests cautious use in cases requiring high load-bearing capacity.