Procedure time and filling quality for bulk-fill base and conventional incremental composite techniques—A randomised controlled in vitro trial

•The bulk-fill base technique shortened the time to fill a cavity by 59.8 %.•The usual filling technique of choice was not associated with the procedure time.•The bulk-fill base technique improved the immediate quality of the fillings.•Switching from one technique to another does not appear to introduce undue risks.•The operator's experience was not associated with the procedure time. The aims of this randomised controlled laboratory trial were to determine the procedure time and immediate quality (surface porosity and marginal gaps) of fillings placed using the bulk-fill base technique and the conventional incremental technique in simulated clinical settings. Forty-two dentists and dental students were randomly allocated to use either the bulk-fill base technique or the conventional incremental technique to fill an identical class II disto-occlusal cavity in a maxillary left first molar typodont tooth. We recorded the time the participants used to fill the cavity and evaluated the surface porosity and marginal gaps on the approximal surfaces of the fillings using a stereomicroscope and specific probes according to the FDI criteria for restoration evaluation. Data were analysed using the Mann–Whitney U, Kruskal–Wallis, and chi-square tests. The median time ± interquartile range was 186 ± 80 s for the bulk-fill base technique and 463 ± 156 s for the conventional incremental technique (p