Table 2 Summary of the outcomes related to flexure strength
Study ID | Testing method for strength | Flexure strength (MPa) | Post-processing or treatment applied | Conclusion | Limitations |
[39] | Universal testing machine | PR = 79.54 CH = 95.58 CC = 104.20 | Polymerization | Heat-activated polymerized PMMA (CH) resin (CC) had the highest flexural strength. | Study design |
[29] | Universal testing machine | SLA method = 116.08, DLP Acrylate photopolymer = 46.83, DLP Bis-acrylic = 146.37, Milled PMMA = 168.57, Conventional PMMA = 89.54 | NA | 3D printing demonstrated clinically flexural strength to those produced using subtractive manufacturing and traditional methods | NA |
[1] | Universal testing machine | Mean: DLP = 1189, SLA = 1323, FDM group did not break | NA | The flexural strength of the DLP and SLA groups was markedly more significant than the conventional group, as indicated by a statistically significant difference (p < 0.001) | Study design |
[36] | 3-point flexural bend test | > 50 | Post polymerization | Enhanced effectiveness can be achieved by subjecting the printed specimens to post-polymerization in a more robust post-polymerization unit. | Flexural strength was assessed in narrower samples, adhering to the guidelines outlined by ISO standards. |
[34] | 3-point flexural bend test | NextDent = 56.4 Control = 93.4 | Polymerization and Heat-polymerization for control resin | When compared to heat-polymerized specimens, 3D-printed specimens showed lower flexural strength | Accuracy measurement, lack of thermal, water aging |
[37] | 3-point flexural bend test | No significant differences. | Ultraviolet polymerization | Digitally produced intermediate materials outperformed traditionally polymerized materials in terms of mechanical characteristics | NA |
[31] | 3-point flexural bend test | SLA = 48.9 SLS = 77.3 Acrylic resin = 69.2 Bis-acryl resin = 75 | Polymerized with light | SLS resin demonstrated positive outcomes, showcasing higher maximum flexural strength | Orientation angles and new types of resins were missing. |
[30] | Universal testing machine | Graphy = 329.3 NextDent = 177.8 | NA | 3D-printed resin crowns might present a viable alternative for fabricating fixed prostheses for primary teeth | Study design |
[38] | 3-point flexural bend test | 3DCS = 143 3DOS = 141 CHP = 76 CAP = 88 | Polymerization | The tested 3D-printed interim resins outperformed the traditional resins | A limited number of materials were investigated and tested |
[32] | 3-point flexural bend test | Cosmos Temp = 56.83 Evolux PMMA = 111.76 Structur 2 SC = 87.34 | post-polymerized with 3000 flashes of ultraviolet light | Although the mechanical qualities of the milled resin were more significant or comparable to those of the bisacrylic resin, the 3D-printed resin was statistically inferior to both the milled and bisacrylic resins | Orientation angles were not considered |
[33] | 3-point flexural bend test | 3D printed = 81.33 Acrylic resin = 72.90 Nanofilled composite resin = 34.97 CAD/CAM PMMA resin = 94.63 Bis-acryl composite resin = 91.57. | NA | Except for 3D-printed resin, thermocycling lowered the flexural strength of most temporary materials | NA |
[35] | 3-point flexural bend test | Before accelerated aging (pre-aging), the flexural strength of the A2 group (151 ± 7) was greater (p < 0.05) than that of the other groups. | Polishing and aging | After aging, the flexural strength of the 3D-printed interim resins varied based on the material, system, and printing angle. | Study design, missing data |
[40] | Piston-on-three-balls method (P3B) | 3D = 83.5 Polymer-infiltrated ceramic network = 140.3 Nanohybrid composite resin = 237.3 | NA | The 3D-printed composite resin exhibited the lowest mechanical properties | Staircase approach |