Comparative Analysis of 3D Printing, Computer Aided Design and Milling and Conventional Fabrication Techniques on Fracture Resistance of Interim Restorations: A Systematic Review and Meta-analysis
Authors: Sankeshwari Banashree , Kanitkar Aditi , Pattanshetti Channaveer , Kanitkar Aneesh 
Published: February 2025

Introduction: The fracture resistance of interim restorative materials is important for success of dental restorations. Various fabrication methods have been employed to create provisional restorative materials, but impact of these methods on fracture resistance remains unclear. Understanding the influence of different fabrication techniques of interim restorative materials on fracture resistance is essential for optimising clinical outcomes, patient satisfaction, and overall dental treatment success.

Aim: To compare the effect of different fabrication techniques on fracture resistance of interim restorations.

Materials and Methods: A systematic search was conducted in electronic databases, which included PubMed, Scopus, and Corrections: Web of Science (WoS), to identify relevant studies published. Studies were included if they met the following criteria: Investigate the fracture resistance of provisional restorative materials, compare different fabrication techniques, published in English and peer-reviewed articles. Studies were excluded if they do not meet these criteria or are not available in full text. The quality of included studies was assessed using a validated tool modified Consolidated Standards Of Reporting Trials (CONSORT) checklist. A meta-analysis was performed to quantitatively analyse the effect of different fabrication techniques on the fracture resistance of provisional restorative materials. Subgroup analyses and sensitivity analyses was conducted if necessary.

Results: The initial search yielded 254 potential articles. After removing duplicates and conducting a thorough screening of titles, abstracts, and full texts, 17 articles met the inclusion criteria for the study which were included for qualitative analysis. Data were extracted regarding the authors' details, the journals and years of publication, different fabrication methods and materials and evaluation of fracture resistance. The result revealed that there was no statistically significant difference for fracture resistance between Computer Aided Design and Computer Aided Manufacturing (CAD-CAM) and 3D-printed interim restorations {Mean difference=50.72 (95% CI=143.55, 244.99)} whereas there was statistically significant difference between CAD-CAM and conventional restorations {mean difference=282.58 (-411.59, -153.47)} and 3D printed and conventional interim restorations {Mean difference=169.75 (95% CI= 353.68, 14.17)}. The p-value is not significant but there is difference seen.

Conclusion: Polymethyl Methacrylate (PMMA) CAD/CAM milled interim restorations demonstrated the highest fracture resistance among the groups compared in the study. This finding highlights the superior durability and strength of CAD/ CAM milling technology, particularly when using PMMA as the material for fabricating provisional restorations. The precise and controlled nature of the milling process ensures a strong, reliable restoration with high fracture resistance, making it the ideal choice for many clinical situations. A 3D-printing was shown to be a stronger and more reliable manufacturing method for interim restorations when compared to traditional conventional techniques (such as indirect methods). Although 3D-printed restorations exhibited lower fracture resistance than CAD/CAM milled restorations, they still offer a significant advantage over conventional techniques in terms of strength and reliability. This suggests that 3D-printing can be a viable alternative, especially when CAD/CAM milling is not available or feasible.