Entwicklung eines neuen Applikationsverfahrens für fließfähige Komposite zur Reduktion polymerisationsbedingter Spannungen
Loading...
Files
Date
Authors
Publisher
Philipps-Universität Marburg
Supervisors
Abstract
The polymerisation shrinkage and the resulting stress in teeth is one of the
most frequent reasons of composite restorations failing today. Therefore, the
composite research has been dealing with this problem for years.
To reach a suitable adhesion of the filling and a sufficient polymerisation of the
composite, the incremental technique (by using a conventional composite) is
state of the art. However, this technique is time-consuming. To save time when
filling big cavities, so-called bulk-fill composites were launched several years
ago and became increasingly popular. For this study the two bulk-fill
composites SDR® (Dentsply DeTrey, Konstanz, Germany) and x-tra base
(VOCO, Cuxhaven, Germany) were researched.
Based on the “Gradientenmodell” by Sommer and Gente we hypothesized that
precuring the composite during application could reduce the stress significantly.
This is achieved by inducing the gel-phase of the composite immediately after
its adaption to the cavity wall. Using this method the “gel-shrinkage” of the
composite applied before should be reduced by the subsequent flow of the
material. The appropriate amount of light is crucial for the success. Basis of
comparison was the bulktechnique (according to the manufacturer’s
information) and the incrementaltechnique. The stress measurement was
performed by using the established photoelastic method.
The present study is believed to demonstrate a new solution to reducing stress
and show a first technical implementation of the aforementioned method.
This was achieved by putting a white LED onto the application gun. By using an
analogue computer an automated adjustment of the curing light was reached,
and the composite could be applied at variable speeds. This application method
and device were registered as an invention by Prof. Dr. M. Gente and myself.
The Philipps-University (Marburg, Germany) applied it for a patent.The results of the research show a significant reduction of the stress by using
the precuringtechnique. An overall conclusive explanation of the observed
stress reduction could be made by the extension of the „Gradientenmodell“ by
Sommer and Gente from three to four phases.
A difference in the effectiveness of the precuringtechnique between the two
bulk-fill materials arised. Using x-tra base with precuringtechnique is as
effective as the incrementaltechnique; using SDR® with precuringtechnique
achieved even significantly lower stress results. In future an improvement of the
technical realization of this promising method will follow. Likewise the feasibility
of other composites should be looked at.
Review
Metadata
Contributors
Supervisor:
Dates
Created: 2014Issued: 2014-11-18
Faculty
Medizin
Publisher
Philipps-Universität Marburg
Language
ger
Data types
DoctoralThesis
Keywords
bulk fillstressPolymerisationsschrumpfungbulk-fillcompositepolymerisation shrinkage
DFG-subjects
StressKomposit
DDC-Numbers
610
show more
Dudda, Simone (1061168662): Entwicklung eines neuen Applikationsverfahrens für fließfähige Komposite zur Reduktion polymerisationsbedingter Spannungen. : Philipps-Universität Marburg 2014-11-18. DOI: https://doi.org/10.17192/z2014.0715.
License
This item has been published with the following license: In Copyright