Measurement of linear polymerization contraction using digital laser interferometry.

Alena Knezevic; Nazif Demoli; Zrinka Tarle; Andrej Meniga; Jozo Sutalo; Goran Pichler

PubMed · 15986955

Measurement of linear polymerization contraction using digital laser interferometry.

Alena Knezevic·Nazif Demoli·Zrinka Tarle·Andrej Meniga·Jozo Sutalo·Goran Pichler

Abstract

Polymerization shrinkage is an unavoidable consequence of resin composite photopolymerization and is one of the most important factors in determining the clinical quality and durability of composite filling. Many different methods of measuring polymerization shrinkage are described in the literature. Digital laser interferometry is a method that enables direct observation of polymerization shrinkage in real time. This study used the digital holographic interferometry method to measure the linear polymerization contraction of composite materials: Tetric Ceram (Vivadent), Spectrum TPH (Dentsply) and Valux Plus (3M Dental Products) polymerized with three different curing modes of the Elipar Trilight (ESPE) halogen curing unit. The highest polymerization contraction was recorded by "standard mode" (ETS) (1.24 +/- 2.66% lin), and the lowest by "medium mode" (ETM) (0.40 +/- 0.41% lin) during 40 second illumination. The "exponentional mode" (ETE) showed the highest expansion during the first 10 seconds of illumination. Curing units with initial low intensity enable better inner adaptation of composite material, preventing the detachment of material from dentin during polymerization and avoiding the negative consequences of polymerization shrinkage.

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Composite Resins Interferometry Lasers Light Polymers Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't

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Alena Knezevic, Nazif Demoli, Zrinka Tarle, Andrej Meniga, Jozo Sutalo, Goran Pichler. Measurement of linear polymerization contraction using digital laser interferometry.. https://pubmed.ncbi.nlm.nih.gov/15986955/

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