Identifying indirect restorations using 2-dimensional imaging and three-dimensional imaging by using low dose and standard protocols on 2 different cone beam computed tomography (CBCT) machines

Abstract

Aim

The present research aims to evaluate how or whether clinicians can use 2-dimensional and 3-dimensional imaging modalities to identify different indirect restorative materials inside a patient's oral cavity, qualitatively and quantitatively, by looking at their densities and radiographic appearances on two and three-dimensional imaging.

Materials and Methods

The crowns of the fixed indirect restorative materials, gold, lithium disilicate, PFM, lava, and zirconia, were imaged using 2-dimensional imaging; charge-coupled device sensor and 3-dimensional imaging using both low-dose cone beam computed tomography (CBCT) scan protocol and standard 360-degree CBCT scan using I-cat and standard 360-degree CBCT scan using Prexion CBCT machines, respectively. The sample calculation was done by using, F tests – analysis of variance. Taking an alpha error of 5% and the power required of 90% of the sample size of 5 gave 100% power. The radiographs were qualitatively and quantitatively analyzed by 2 calibrated dental students. The radiopacity of the indirect restorations was compared with the graduated aluminum 9-mm step-wedge and by using CBCT gray values.

Results

Density values when compared with the aluminum step and the CBCT gray values were variable for the aforementioned indirect restorative materials. In addition, the CBCT gray values were greater in the low-dose protocol as compared to the standard acquisition parameters. The higher the CBCT gray values, the more scatter. There was not any evidence of scatter by Lava on any machine/ or any protocol, normal or low dose protocol. The CBCT gray values change with the setting of the scan and were variable from machine to machine. Overall, qualitatively, these metallic restorations were better visualized on 2-dimensional imaging.

Conclusion

Radiographic assessment tools can aid the dental practitioner in differentiating between different fixed restorative materials in the mouth. On a 2-dimensional radiograph, assessment appears to be more reliable as compared to 3-dimensional imaging.