Date of Award

Fall 2023

Document Type


Degree Name

Master of Science (MS)





First Advisor

Bedran-Russo, Ana

Second Advisor

Karczewski, Michael

Third Advisor

Berzins, David


Introduction: Additive manufacturing is being integrated into various aspects of clinical prosthodontics due to its potential for use in various indications and the promise of improved clinical efficiency and properties.Objective: The purpose of this in-vitro study was to evaluate the flexural strength of two 3D-printed resin composites in relation to a conventionally fabricated resin composite after being subjected to two different artificial aging methods: thermocycling and distilled water storage. Material and methods: A total of 220 samples were fabricated (N=220); 72 samples were fabricated from Integrity composite (Dentsply Sirona) and 148 samples were fabricated from two 3D-printed composite materials MFH and CROWNTEC (NextDent). The conventional material (Integrity composite) was dispensed from an auto mixer into a mold adhering to ISO 4949 sample dimensions of 25x2x2 mm. The 3D-printed samples were designed to the same standard. The designing process was carried out on a CAD software Meshmixer (Autodesk) and printed using a NextDent 5100 (3D systems), followed by an alcohol rinse and post-printing polymerization. The samples were finished and divided into 3 sub-groups: non-aged, thermocycling, and distilled water aging. The non-aged group was preserved in distilled water for 24 hours, the thermocycled group was cycled for 700 cycles using a well-known protocol consisting of alternating water baths between 5°C and 55°C water bath, and the water storage group was stored in distilled water for 1 month. The samples were subjected to a three-point flexural test using a universal testing machine (Instron). Data were statistically analyzed using statistical software R at a 95% confidence interval. Results: The results showed the mean ± standard deviations for flexural values for Integrity was 76 ±31 MPa, MFH 148 ± 16 MPa, and CROWNTEC 173±21 MPa. One-way analysis of variance showed statistically significant differences among the groups (p < 0.05). Conclusions: From the results of this study, it was concluded that all the materials performed above the clinical acceptability threshold of 60 MPA set by ISO standard 4049. FS was highest for CROWNTEC, followed by MFH then Integrity. FS was not affected by artificial aging techniques except for CROWNTEC which showed lower FS after water aging for 1 month.

Available for download on Saturday, August 31, 2024

Included in

Dentistry Commons