Biaxial flexural strength of different provisional restorative materials under chemo-mechanical aging: An in vitro study.

PURPOSE

Durability is a critical factor for the success of long-term provisional restorations. This study evaluated the effect of different storage media and cyclic loading on the biaxial flexural strength of different types of provisional materials.

MATERIALS AND METHODS

Discs (N = 360, 10 × 2 mm) were prepared from different provisional materials; conventional (Protemp 4, Tuff-Temp, Tempron), CAD-CAM milled (VITA CAD-Temp, breCAM.multiCOM), and 3D-printed (Nextdent C&B MFH) (n = 60). Each material group was subdivided into four subgroups according to the storage media (n = 15): nonaged, artificial saliva, mouthwash, and coffee. The specimens in storage media were placed in an incubator at 37°C for 4 weeks followed by 60,000 simulated chewing cycles. Biaxial flexural strength test was done. Data were analyzed using two-way ANOVA. Weibull distribution parameters were estimated.

RESULTS

Both the material and aging protocol showed a significant effect on the biaxial flexural strength. Both Protemp 4 and Nextdent C&B MFH showed a significantly higher biaxial flexural strength before and after aging compared to all other materials. Protemp 4 and Tuff Temp showed a significant decrease in strength with aging. CAD-CAM materials showed higher Weibull moduli.

CONCLUSIONS

The 3D-printed polymethylmethacrylate provisional material presents with both greater biaxial flexural strength and increased durability against chemical and mechanical aging compared to conventional and CAD-CAM milled provisional materials tested.