Accuracy of implant impression using a multifunctional guide in the all-on-four treatment concept

Abstract

Introduction: The passivity of prosthetic components is one of the most important prerequisites in oral implant rehabilitation for maintenance of osseointegration. Objective: Thus, the present study analyzed in vitro the accuracy of different molding techniques in prosthetic rehabilitation on angled implants installed in an anatomical model of a metallic edentulous maxilla. Methods: Laboratory experiment study. A reference metal model of an edentulous maxilla was used. A metal framework was used for the misadaptation assessment. Three groups (n= 10) were compared and impressions were made with vinylpolysiloxane and casts were obtained with type IV stone: (1) Impression with a metallic open-tray without splinted transfers; (2) Impression with a metallic open-tray and metal splinted transfers; (3) Impression with a multifunctional guide and metal splinted transfers. Misadaptation was assessed with the aid of a stereomicroscope and measuring software. Data were submitted to ANOVA with Welch correction and the Games-Howell post-hoc test with the significance set at 5 %. Results: Misadaptation (µm) was 110,23 ± 30,94, 37,53 ± 3,92, and 37,69 ± 2,79 for the the groups. Statistically significant differences between impression with a metallic open-tray with and without splinted transfers were observed (p < 0,001). No significant differences between the other types of impression. Conclusions: Impression with a metallic open-tray without splinted transfers and with a multifunctional guide splinted with metal transfers were the most precise methods resulting in higher accuracy in transferred implants.