Contact angle comparison of two elastomeric impression materials during initial setting.

Introduction: Hydrophilicity of elastomeric impression materials is a key property in producing an accurate impression in prosthodontic treatment.
Aim: To study the hydrophilicity (wettability) of two different elastomeric impression materials in vitro by comparing the initial water contact angles on five materials during setting.
Materials and methods: Vinyl polysiloxane VPS (Imprint 4 Light and Super Quick Heavy) and Vinyl polyether silicone VPES (EXA’lence Light Regular, Light Fast and Heavy Fast set) were used. The leveled material surface received 1-μl droplet of deionized water 15 seconds after dispensing the impression material. Contact angles were measured at 0, 30, 60, 90, 120, and 150 seconds using a drop shape analysis machine. The data were analyzed using repeated measures ANOVA with time as a within-subjects factor and material as a between-subjects factor (α=0.05).
Results: All material had high contact angles at time 0 (T1). Imprint 4 had lower contact angles than EXA’lence at all times. There was a statistically significant difference in contact angles of all EXA’lence materials compared to Imprint 4 when not accounting for time (P < .001). When time was factored in, there was no significant difference at T1 only (P = .08). There was no significant difference among the three EXA’lence materials (P > .990) at all-time points. However, there was a significant difference between Imprint 4 materials with Imprint 4 Super Quick Heavy having lower means than Imprint 4 Light (P = .001). This was true for all time points except T1.
Conclusions: Despite the high contact angle values at time 0 (T1), both materials reached a significant hydrophilic level with Imprint 4 having drastically lower mean values.

DOI: https://doi.org/10.62838/ASMJ.2024.2.03