Comparative Analysis of Dimensional Accuracy in the Integration of Different Setting Times of Impression Materials

Abstract

Background: Dental impressions are essential in restorative and prosthetic dentistry, as their accuracy directly impacts the fit and functionality of dental prostheses. The selection of impression material and its corresponding setting time plays a crucial role in determining final dimensional precision. This in vitro study aimed to assess the dimensional accuracy of dental impressions created using various combinations of impression materials with different setting times, providing evidence-based guidance for clinicians in selecting optimal and reliable material combinations. Materials and Methods: A total of 72 samples were divided into three groups: Fast-Fast (light body fast-set and regular body fast-set), Fast-Normal (light body fast-set and regular body normal-set) and Normal-Fast (light body normal-set and regular body fast-set). Impressions were taken from a typodont using polyvinyl siloxane (Aquasil Ultra, Dentsply Sirona). Digital impressions were created using a Zirkonzahn scanner and superimposed onto a digital reference cast. Six parameters related to height and width were measured using Exocad software. Results: Statistically significant differences were found between the groups for buccal (p = 0.0002), mesiodistal (p = 0.0002) and buccopalatal (p = 0.006) dimensions. The Fast-Normal group exhibited significantly higher mean values for these parameters than did the Fast-Fast and Normal-Fast groups. Conclusions: Mixing fast set and normal set time impression materials changed the measurements slightly. The combination of impression materials with different setting times significantly affected dental impressions, particularly the buccal, mesiodistal and buccopalatal dimensional aspects. These findings suggest that careful consideration of impression material properties, such as setting time, is crucial to ensure the dimensional accuracy and optimal fit of prosthetic restorations. Clinical Significance: This research aims to evaluate and validate alternative impression methods for clinical cases where material availability is limited, by comparing the dimensional accuracy of dental impressions made with different material combinations. Through rigorous assessment of accuracy measurements and significant differences between various material combinations, the study seeks to provide evidence-based solutions that address the practical challenges of material accessibility and availability in dental clinics. This research will ultimately help dental practitioners make informed decisions about impression material selection when faced with supply limitations, ensuring they can maintain clinical standards while working with alternative material combinations that have been proven to deliver acceptable accuracy.