Effects of flowable liners on the shrinkage vectors of bulk-fill composites

• DOI: 10.1007/s00784-021-03801-2
• Publication Date: 2021-01-27T22:03:07Z
• Authors: Dalia Kaisarly; D. Meierhofer; M. El Gezawi; P. Rösch; K.H. Kunzelmann
• Keywords: Shrinkage; Radiodensity; Thin layers; Resin composite

This investigation evaluated the effect of flowable liners beneath a composite restoration applied via different methods on pattern shrinkage vectors.Forty molars were divided into five groups (n = 8), and cylindrical cavities prepared bonded with self-etch adhesive (AdheSe). Tetric EvoCeram Bulk Fill (TBF) was used as filling material in all cavities. The EvoFlow (TEF) SDR to line cavity floor. In gp1-TBF, not used. TEF thin layer gp2-fl/TEF + TBF gp3-fl/TEF TBFincremental. Two composites thickness 2 mm compared gp4-fl/TEF gp5-fl/SDR TBF. mixed radiolucent glass beads, while air bubbles inherently present served markers. Each application scanned twice by micro-computed tomography before after light curing. Scans subjected image segmentation for calculation vectors.The absence liner resulted greatest vectors. A (gp2-fl/TEF TBFbulk) larger overall vectors whole than thick (gp4-fl/TEF TBF). incremental (gp3-fl/TEF TBFincremental) yielded smallest slightly smaller that observed TBF.Thick layers had more pronounced stress-relieving regardless type.It is recommended apply (thin or thick) bulk-fill composites, preferably incrementally.