Influence of impression technique on the amount of occlusal adjustments of indirect restorations – case report (Atena Editora)

Abstract

Introduction: Impressions are classified as the total or partial, work or study, and we want to present the classification into active and passive impressions and their relationship with the amount of occlusal adjustments in the final restoration. Passive impression does not put pressure on the teeth to push them into the sockets and the teeth are copied without dento-alveolar movement. Active impression occurs when we mold teeth and adjacent structures with the double-arch technique, a closed-mouth impression, copying the prepared and opposing tooth, including the interocclusal registration. In the plaster model obtained, the teeth are intruded, positioned in the socket in sync with the end of the mandibular closing arch.

Objective: To test the amount of occlusal adjustment needed in indirect restorations after using active and passive impression.

Report: Eight all-ceramic crowns were made with different levels of digital and analog phases until reaching 100% digital phases. The analysis for the need for occlusal adjustment was performed using a double-blind test using a numerical score from 1 (very high) to 4 (excellent).

Results: A comparison using MEDIANs showed that the 100% digital crown received a score of 4 the three times it was installed for TEST, followed by the 60% digital-40% analog crown which received two scores of 3 and one score 2 and the 50% digital crown -50% analog, which received three scores 3.

Conclusions: The more digital phases, the less the need for occlusal adjustment, and crowns made from active impressions obtained better scores when compared to those made from passive impressions.