Linear dimensional change of edentulous models made of high-density laboratory silicones at different storage times

Alteração dimensional linear de modelos edêntulos fabricados com silicones laboratoriais de alta densidade em diferentes tempos de armazenagem

ABSTRACT

Objective:

To evaluate the dimensional change of edentulous models made of high density laboratory silicones at different storagetimes.

Methods:

A metallic master model simulating an edentulous maxilla was used. The model had projections of 1.8 cm located in the regions of canines (A and B) and molars (C and D) allowing the linear measurement of distances AB, BC, CD, DA, AC and BD. A laboratory silicone mold was made for duplication of master model in the following materials (n = 10): G1: Zetalabor 85, G2: Titanium 95, G3: Platinum 95 and G4: Gypsum type III (control). The samples were photographed and measured using a software (Image J) at times T1 (baseline) and T2 (after one week of models fabrication). The data were statistically analyzed using Kruskal- Wallis and Dun non-parametric tests (α = 0.05).

Results:

The storage time influenced the behavior of the materials evaluated. All groups presented dimensional changes in both times and the group Tit95 presented the best results. Only Zet85 group showed a different behavior related to the region of the model.

Conclusions:

The high density laboratory silicones showed satisfactory results when compared to the gypsum group. Tit95 was the most stable material and it can be recommended as an edentulous model for total protheses.

Indexing terms
Silicone elastomers; Dimensional measurement accuracy; Complete denture