The effect of disinfectants on dimensional stability of addition and condensation silicone impressions

Abstract

Background/Aim. Dimensional stability and accuracy of an impression after chemical disinfection by immersion in disinfectants are crucial for the accuracy of final prosthetic restorations. The aim of this study was to assess the deformation of addition and condensation silicone impressions after disinfection in antimicrobial solutions. Methods. A total of 120 impressions were made on the model of the upper arch representing three full metal-ceramic crown preparations. Four impression materials were used: two condensation silicones (Oranwash L - Zhermack and Xantopren L Blue - Heraeus Kulzer) and two addition silicones (Elite H-D + regular body - Zhermack and Flexitime correct flow - Heraeus Kulzer). After removal from the model the impressions were immediately immersed in appropriate disinfectant (glutaraldehyde, benzalkonium chloride - Sterigum and 5.25% NaOCl) for a period of 10 min. The control group consisted of samples that were not treated with disinfectant solution. Consecutive measurements of identical impressions were realized with a Canon G9 (12 megapixels, 2 fps, 6x/24x), and automated with a computer Asus Lamborghini VX-2R Intel C2D 2.4 GHz, by using Remote Capture software package, so that time-depending series of images of the same impression were obtained. Results. The dimensional changes of all the samples were significant both as a function of time and the applied disinfectant. The results show significant differences of the obtained dimensional changes between the group of condensation silicones and the group of addition silicones for the same time, and the same applied disinfectant (p = 0.026, F = 3.95). Conclusion. The greatest dimensional changes of addition and condensation silicone impressions appear in the first hour after their separation from the model.

Uvod/Cilj. Dimenzionalna stabilnost i preciznost otiska posle hemijske dezinfekcije potapanjem u dezinficijens predstavljaju osnovu za preciznost definitivnih zubnih nadoknada. Cilj ovog istraživanja bio je da se proceni dimenzionalna stabilnost otisaka izrađenih od adicionih i kondenzacionih silikona posle dezinfekcije u antimikrobnim rastvorima. Metode. Napravljen je uzorak od 120 otisaka, dobijenih otiskivanjem modela gornje vilice sa ispreparisanim zubima za metalokeramičke krune. Od otisnih materijala korišćena su dva kondenzaciona silikona (Oranwash L - Zhermack i Xantopren L Blue - Heraeus Kulzer) i dva adiciona silikona (Elite H-D + regular body - Zhermack i Flexitime correct flow - Heraeus Kulzer). Odmah po odvajanju od modela, otisci su potopljeni u odgovarajući dezinficijens (glutaraldehid, benzalkonijum-hlorid - Sterigum i 5,25% NaOCl) u trajanju od 10 min. Kontrolnu grupu činili su uzorci koji nisu tretirani dezinficijensom. Uzastopna merenja istovetnih otisaka vršena su pomoću fotoaparata Canon G9 (12 megapiksela, 2 fps, 6x/24x), a automatizovana sa računara Asus VX 2R Lamborghini- Intel C2D 2,4 GHz, korišćenjem opcija softverskog paketa Remote Capture tako da su dobijene vremenske serije fotografija istog otiska. Rezultati. Utvrđene su izražene dimenzionalne promene svih uzoraka kako u funkciji vremena tako i u funkciji primenjenog dezinficijensa. Rezultati pokazuju postojanje značajnih razlika dimenzionalnih promena između grupe kondenzacionih silikona i grupe adicionih silikona za isto vreme i isti primenjeni dezinficijens (p = 0,026, F = 3,95). Zaključak. Najveće dimenzionalne promene otisaka uzetih adicionim i kondenzacionim silikonima beleže se u prvom satu po odvajanju sa modela.