Incorporation of opacifier to Type III alpha gypsum and its effect on scannability and linear setting expansion - An in vitro study.

Aim: This study aims to enhance the scannability of Type III alpha gypsum by incorporating an opacifier and to evaluate its effect on the LSE property.

Setting and design: In vitro - Comparative study.

Materials and methods: The base powder of Type III alpha gypsum was divided into three groups: Group I (100 g of base powder), Group II (90 g of base powder with 10 g of TiO2), and Group III (80 g of base powder with 20 g of TiO2). The study had two parts: First, scanning the mixtures to determine the best scannable material; second, testing for LSE using a plaster extensometer with 0.01 mm precision. Each group's scannability was assessed using a Medit lab scanner, and their LSE was measured.

Statistical analysis used: One-way ANOVA with Tukey's post-hoc test for multiple comparisons.

Results: Results showed that there was a statistical significance between the three groups. However, there was a decrease in the LSE with an increase in the concentration of the titanium dioxide (TiO2). Group III has shown superior scanning properties compared to the other groups.

Conclusion: Type III alpha gypsum reinforced with 20% TiO2 as an opacifier has exhibited superior scanning properties and there was a statistically significant decrease in the LSE between all three groups with increase in the concentrations of TiO2.