Table 2 Resin materials used in the study and application steps

Qu resin / Qu connector (QR)

- The surface was sandblasted with 110 μm aluminum oxide.

- The surface has been cleaned with oil-free compressed air.

- Qu-connector implemented. Irradiated for 90 s.

- Qu-resin was injected.

- The polymerization time of the material is approx. 5 min.

Quick Up / Quick up adhesive (QP)

- Quick up adhesive was applied using an applicator.

- Adhesive was air dried for 30 s.

- Quick up was injected.

- The polymerization time of the material is approx. 2 min.

Ufi Gel Hard / Ufi Gel Hard Adhesive (UGH)

- Conditioner was applied and left to dry for 30 s.

- Ufi Gel hard powder/liquid was mixed homogeneously in a 3/1 ratio.

- The polymerization time of the material is 7–8 min.

Pattern Resin LS Powder / Liquid (PR)

- The brush was wetted with the liquid and the powder was picked up, according to the manufacturer instruction. The gap was built up, layer by layer.

- The working time of the material is 2–3 min.

- The hardening time of the material is 4 min.

Futura Basic Hot Powder / Liquid (FBH)

- The mixing ratio of Futura Basic Hot is approximately 2.5 parts powder to 1 part liquid by weight.

- After the powder of the material was added to the liquid, it was mixed for 30 s until a homogeneous mixture was obtained.

- It was cooked in a pressure cooker at 95 degrees and 2–4 bar pressure for 20 min.