Insertion Forces of VPS Automixed Putty Impression Materials

Objectives:

When using VPS impression materials in the putty/wash technique, an accurate impression can best be achieved if sufficient force is exerted on the wash material resulting in adequate “flash” beyond the margins of the preparation.  Therefore, one valuable property of VPS putty material is the high level of insertion force created during tray seating. In this study, we investigated the insertion force (IF) of both conventional hand-mix and auto-mixed silicone putty materials compared to a heavy body silicone impression material.

Methods:

A new 3M ESPE Penta Putty Soft development (ExpPPS, 3M ESPE) was compared to conventional hand-mix products: Affinis Putty Super Soft (AfPSS, Coltene), Honigum Putty Soft (HoPS, DMG) and Optosil Comfort (OpC, Heraeus). To differentiate putties from heavy bodies, Imprint 3 Penta Heavy Body (ImPHB, 3M ESPE) was used as a control. The measurements were conducted on a Zwick Z010: Equal quantities of each material were placed between specially formed stamps and moved together with the same velocity, 1 minute after start of mix. The insertion force (IF) needed to reach a defined distance of 2 mm between the stamps was recorded.

Results:

As shown by ANOVA (p<0.05), the range of the IF of handmix putties is in the area of about 2500 N to 5300 N. The experimental automix putty can be found in the upper range. The mean IF and standard deviations (SD) are given in the following table:

Material Lot	ImPHB B314290 C314527	ExpPPS B296199 C314679	AfPSS 0137045	HoPS 574604	OpC B280134 C270296
IF [N]	818	4355	5113	2602	4212
SD	40	130	237	109	286

Conclusions:

ExpPPS showed the behavior of a true putty with regard to insertion force as compared to the hand-mixed material and the control.  The data supports the suitability of the auto-mixed ExpPPS for clinical use.