Accuracy of newly formulated fast-setting elastomeric impression materials

Area of Science:

• Dental Materials Science
• Impression Techniques
• Biocompatibility and Disinfection

Background:

• Reformulation of elastomeric impression materials aims for faster setting times.
• Assessing the dimensional accuracy of these fast-setting materials, especially after disinfection, is crucial for clinical reliability.

Purpose of the Study:

• To evaluate the accuracy of two fast-setting elastomeric impression materials after disinfection with acid glutaraldehyde.

Main Methods:

• Impressions of a master model were made using fast-set vinyl polysiloxane (VPS-FS) and fast-set polyether (PE-FS), compared to a regular-setting polyether (PE).
• Disinfection was performed using 3.5% acid glutaraldehyde immersion; non-disinfected impressions served as controls.
• Linear dimensions (anteroposterior, cross-arch, buccolingual, mesiodistal, occlusogingival) of master models and gypsum casts/dies were measured using a measuring microscope.

Main Results:

• No significant differences in accuracy were found between disinfected and non-disinfected impression materials.
• All materials exhibited statistical differences in anteroposterior, cross-arch, mesiodistal, and occlusogingival dimensions.
• Polyether materials (PE and PE-FS) produced larger dies, while vinyl polysiloxane (VPS-FS) produced smaller mesiodistal and occlusogingival dimensions compared to the preparation.

Conclusions:

• Immersion disinfection with acid glutaraldehyde did not compromise the accuracy of the tested elastomeric impression materials.
• Polyether and fast-set polyether impression materials yielded similar results, whereas fast-set vinyl polysiloxane required consideration for potential die relief.
• Despite minor dimensional variations, all three tested impression materials demonstrated acceptable overall accuracy.