Page 25 - COS-FOD2015

Compendium of Oral Science Volume 1|2015

Original Article
Detail Reproduction of Elastomeric Materials: Effect of
Viscosity and Groove Geometry

1
4
2
3
Nik Zarina Nik Mahmood* , Noor Hayaty Abu Kasim , Mamat Azuddin , Noor Lide Abu Kassim
1 Centre of Comprehensive Care Studies, Faculty of Dentistry, University Technology MARA Sg. Buloh Cam-
pus, Jalan Hospital, 47000 Sungai Buloh, Malaysia.
2 Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
3 Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia

4 Faculty of Dentistry, International Islamic University of Malaysia, 68100 Kuala Lumpur, Malaysia

Abstract
Objective: To evaluate the effect of type of viscosity and groove on surface detail reproduction of elastomeric
impression materials. Methods: Two polyvinylsiloxane and polyether elastomeric impression materials were
investigated. An aluminium cylindrical reference block with V- and U-shaped grooves of 1 mm and 2 mm in
depth was machined using CAD-CAM system. Impressions of the block were taken to produce 35 master dies.
Each die was immersed in distilled water for 5 minutes prior to impression making. Surface topography of the
dies and impressions were captured using Alicona Imaging System. Mean difference in depth between the mas-
ter dies and corresponding impressions’ grooves were analyzed. Results: Type of viscosities and groove
showed significant main effects on surface detail (p < .01), but no significant interaction was observed between
the two (p > .01). Express™ putty/light exhibited the lowest mean difference in depth for all grooves. The highest
mean difference for U 1 (38.3μm ± 21.55), U 2 (52.96μm ± 30.39),V 1 (45.02μm ± 34.82) and V 2 (58.44μm ± 44.19)
was obtained from Impregum medium, Aquasil medium, Impregum™ heavy/light and Impregum™ heavy/light
groups respectively. Conclusion: Express putty/light-bodied material produced the best surface detail, and U-
shaped groove showed superior detail reproduction.

Key words: elastomeric materials, surface detail, effect of viscosity, groove geometry, mean difference
in depth.

Introduction their superior properties which include dimen-
sional accuracy and stability (1,2), excellent
Elastomeric impression materials are used to
elastic recovery, ease of handling, ability to pro-
record the margin of prepared tooth and the
duce multiple casts and good detail reproduci-
surrounding soft tissue for the fabrication of
bility (3,4). During impression making, the ma-
definitive restorations. Currently, polyether (PE)
terials are in contact with moisture such as sali-
and polyvinylsiloxane (PVS) are the most wide-
va, gingival exudate and blood around the gin-
ly used elastomeric impression materials due to
giva (2). The widespread use of PE and PVS is

also attributed to their hydrophilic property and
* Corresponding to: Dr Nik Zarina Nik Mahmood, Centre of ability to flow into small areas and crevices (5).
Comprehensive Care Studies, Faculty of Dentistry, Uni-
versity Technology MARA Sg. Buloh Campus, Jalan
Hospital, 47000 Sungai Buloh, Malaysia. The hydrophilicity of elastomeric impression
Email: drnikzarina@salam.uitm.edu.my
Tel: +603-61266637, Fax: +603-61266684

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