Cuspal Deflection in Premolar Teeth Restored with Bulk-Fill Resin-Based Composite Materials

Area of Science:

• Restorative Dentistry
• Dental Materials Science

Background:

• Minimally invasive cavity preparations are increasingly common.
• Bulk-fill resin composites offer potential advantages in clinical efficiency.
• Understanding their impact on tooth structure, such as cuspal deflection, is crucial.

Purpose of the Study:

• To evaluate and compare the cuspal deflection caused by three high-viscosity bulk-fill resin composites.
• To compare the effects of bulk-fill materials against a conventional resin composite placed incrementally.

Main Methods:

• Thirty-two maxillary premolars with large MOD cavities were restored.
• Three bulk-fill materials (Tetric EvoCeram Bulk Fill, x-tra fil, SonicFill) and one conventional composite (Filtek Z100) were used.
• Cuspal deflection was measured using a Nikon measurescope at 5 minutes, 24 hours, and 48 hours post-irradiation.

Main Results:

• All three bulk-fill resin composites demonstrated significantly lower cuspal deflection than the conventional composite.
• No statistically significant differences in cuspal deflection were observed among the three bulk-fill materials tested.
• Conventional composite restorations showed higher cuspal deflection values.

Conclusions:

• High-viscosity bulk-fill resin composites are effective in minimizing cuspal deflection.
• These materials present a favorable alternative to conventional incremental placement for large cavities.
• Clinical application of bulk-fill composites may reduce stress on tooth structure.