Objective: To assess the performance and handling of an automatic impression mixing machine (Pentamix 3*) and its associated polyether impression materials (Impregum Penta Soft Quick* and Impregum Penta H DuoSoft Quick* with Impregum L DuoSoft Quick* in UK general practice (*3M ESPE, Seefeld, Germany). Method: Thirteen general dental practitioner (GDP) members of a UK-wide practice-based research group, The PREP panel, received the machine and materials for ten weeks use, plus a questionnaire to evaluate their current impressioning techniques, and to rate the presentation, instructions, dispensing, and handling of both. Most responses were on a visual analogue scales (V A S). Results: Nine evaluators (69%) previously used hand mixing or a hand dispenser with cartridges to mix impression materials. Eleven (85%) evaluators generally used a full-arch impression, with ten (77%) using a putty/wash technique. The main reasons for choosing impression materials were accuracy & ease of use. 138 impressions were taken and the machine scored more than 4 on VAS (where 1 = very dissatisfied and 5 = very satisfied) for a range of criteria including ease of initial use, easy handling, cleanliness, and overall convenience and between 3 and 4 for the size of the device and countertop space taken up. A maximum score was achieved for reproducible mixing quality. The impression materials achieved a higher score for ease of use then the pre-trial materials (4.3 v 4.0 on a VAS where 1 = poor and 5 = excellent). Eleven (85%) of evaluators would recommend both the auto-mix machine and the materials to colleagues. Conclusions: The new automatic mixing machine, and its associated impression materials received very good ratings and the majority of the GDP evaluators would recommend them both to colleagues.
The support of 3M ESPE , Germany is acknowledged.