Prophylaxis was performed after the cavity preparations in all the dental root blocks using a pumice stone paste (SS White) and distilled and deionized water. The cavities were washed with a water and air spray and air dried.
Preparations in groups 1 and 3 were restored with a resin composite (Filtek Z 250, 3 M ESPE, St. Paul, MN, USA) using 37% phosphoric acid etching and Single Bond 2 adhesive (3 M ESPE, St. Paul, MN, USA) before insertion of the resin composite. The preparations in groups 2 and 4 were restored using conventional glass ionomer cement (GIC) (Ketac Fil Plus, 3 M ESPE, St. Paul, MN) with the aid of a Centrix syringe to avoid the inclusion of bubbles within the restorative material. Subsequently, the GIC was covered with a polyester strip, and a glass slide and weight (500 g) were placed on top for 7 min to standardize the restorations.
The materials were manipulated, and the cavities were restored in accordance with the manufacturer's instructions. The dental blocks were stored for 24 h at 37°C in a 100% humid environment at the conclusion of the restorative procedure, and the blocks were polished using a sequence of aluminum oxide disks (Sof-Lex, 3 M ESPE, St. Paul, MN, USA).
Preparations in groups 1 and 3 were restored with a resin composite (Filtek Z 250, 3 M ESPE, St. Paul, MN, USA) using 37% phosphoric acid etching and Single Bond 2 adhesive (3 M ESPE, St. Paul, MN, USA) before insertion of the resin composite. The preparations in groups 2 and 4 were restored using conventional glass ionomer cement (GIC) (Ketac Fil Plus, 3 M ESPE, St. Paul, MN) with the aid of a Centrix syringe to avoid the inclusion of bubbles within the restorative material. Subsequently, the GIC was covered with a polyester strip, and a glass slide and weight (500 g) were placed on top for 7 min to standardize the restorations.
The materials were manipulated, and the cavities were restored in accordance with the manufacturer's instructions. The dental blocks were stored for 24 h at 37°C in a 100% humid environment at the conclusion of the restorative procedure, and the blocks were polished using a sequence of aluminum oxide disks (Sof-Lex, 3 M ESPE, St. Paul, MN, USA).