Dimensional Accuracy of Novel Vinyl Polysiloxane Compared with Polyether Impression Materials: An In Vitro Study

Area of Science:

• Dentistry
• Dental Materials Science
• Prosthodontics

Background:

• Accurate intraoral impressions are vital for precise dental restoration fabrication.
• Vinyl polysiloxane (VPS) and polyether (PE) are common impression materials.
• Impression techniques, including mono-phase and dual-phase single step, influence accuracy.

Purpose of the Study:

• To compare the dimensional accuracy of hydrophilic quadrofunctional VPS and PE impression materials.
• To evaluate the impact of mono-phase and dual-phase single-step impression techniques on accuracy.
• To assess the clinical acceptability of different material and technique combinations.

Main Methods:

• A reference model simulating a partially edentulous mandible was used.
• Stainless-steel precision balls measured dimensional deviations.
• Four test groups were evaluated: VPS mono-phase, PE mono-phase, VPS dual-phase, and PE dual-phase.
• Global and local accuracy (trueness and precision) were statistically analyzed using ANOVA.

Main Results:

• All tested distances were underestimated, with cross-arch distances showing the highest global inaccuracies (-82 µm to -109 µm).
• Excellent local accuracy was observed for abutment tooth surfaces (crown surface trueness < 10 µm, precision < 12 µm) across all groups.
• Inlay surfaces exhibited higher inaccuracies (trueness < 15 µm, precision < 26 µm).

Conclusions:

• All evaluated impression materials (VPS, PE) and techniques (mono-phase, dual-phase single step) yield clinically acceptable accuracy for dental models.
• Local accuracy for abutment tooth surfaces is highly reliable with these materials and techniques.
• While global accuracy has limitations, particularly for cross-arch distances, the overall results support their clinical use.