Quantifying and comparing the radiopacity of five bulk fill composites in digital dental radiographs – a contribution to human identification

Objectives

: To compare the quantified radiopacity of five bulk fill composites in digital dental radiographs.

Material and methods

: An in-vitro observational study was performed with five dental restoration materials: I) Bulk Fill Surefil SDR+ flow® (Dentsply Sirona®, York, PA, USA), II) Bulk Fill Sonic Fill® (Kerr Corp.®, Orange, CA, USA); III) Filtek Bulk Fill flow® (3M Company®, Maplewood, MN, USA); IV) Tetric N Ceram Bulk Fill® (Ivoclar Vivadent®, Schaan, Liechtenstein); and V) Aura® (SDI Ltd.®, Victoria, Australia). Digital radiographs were taken standardly from four samples of each composite (n = 20). The radiopacity inherent detected in the radiographs was quantified using a 9-level aluminum scale.

Results

: ANOVA and Tukey's test showed statistically significant differences between the radiopacity of all bulk fill composites (p<0.0001), except between I and IV (p = 1.0). Spearman's outcomes revealed that only composite I had positive moderate (rS=0.63) correlation with the respective radiopacity level in the aluminum scale (p = 0.027).

Conclusion

: Most of the bulk fill composites addressed in this study were distinguishable from each other based on their radiopacity. The identification of type and even brand of composites may be a promising task in human identification. However, this procedure remains challenging and the scientific evidence behind it is still scarce in the forensic literature.