Methods: 30 Ivorine teeth (Kavo EWL Model) were used. A standardised MOD cavity preparation was prepared in each one. Teeth were randomly allocated to two groups based on the placement technique (bulk filling or incremental layers) and then restored with a light cure resin-composite (Spectrum TPH universal composite Dentsply UK).
Scanning of all teeth using a micro-CT (Skyscan 1072) was performed followed by 3D reconstruction using NRecon software and analysis using CTAn software. The percentage volume occupied by voids within each restoration was calculated. Data were analysed and compared with a T-test (p< 0.001).
Results: The mean volume of voids within the restoration was greater in the incremental layers group (0.57%) than in the bulk group (0.10%). This difference was statistically significant (p<0.001)
Conclusions: The percentage of voids within a restoration is dependant on technique and is higher with incremental layering. This may have clinical relevant.