Radiopacity of tantalum oxide nanoparticle filled resins

Area of Science:

• Materials Science
• Biomaterials Engineering
• Dental Materials

Background:

• Radiopacity in composite resins is crucial for distinguishing restorations and detecting recurrent caries.
• Current dental composites often require heavy metal-containing fillers for adequate radiopacity.
• Tantalum oxide (Ta2O5) is explored as a novel radiopacifying agent.

Purpose of the Study:

• To evaluate the radiopacity of composite resins filled with Tantalum oxide (Ta2O5) nanoparticles.
• To determine the effect of varying Ta2O5 loading percentages on radiopacity.
• To assess the potential of Ta2O5 as a radiopacifying filler in dental composites.

Main Methods:

• Methacrylate-functionalized Ta2O5 nanoparticles were incorporated into GDMA or GTE resin matrices.
• Specimens were prepared and compared against an aluminum stepwedge and dentin.
• Radiopacity was quantified using optical density measurements and expressed as percent relative linear attenuation coefficient (Alpha).

Main Results:

• Radiopacity demonstrated a significant increase with higher Ta2O5 loading (p = 0.001).
• Resins achieved optimal diagnostic detectability (Alpha = 150-250) at 50 wt.% Ta2O5 loading.
• Approximately 70 wt.% Ta2O5 loading approached the radiopacity of dental enamel.

Conclusions:

• Tantalum oxide nanoparticles show potential as a miscible filler component for resin composites.
• Ta2O5 can provide necessary radiopacity for microfiller-type restorative materials.
• This approach may eliminate the need for hydrolysis-prone glass reinforcing fillers.