Syllabus
Lesson 1. Effect of light intensity, irradiation time and material shade on the polymerization extent of composite and LC glass-ionomer cements. Lesson 2 a 3. Mechanical properties (compression strength, hardness) of restorative materials. Lesson 4. Polymerization contraction of composite materials, disintegration of glass-ionomer cements in aqueous environments.
Lesson 5. Determination of tooth shades using subjective and objective methods. The topic of the exercises might be modified according to specific student interests and teaching demands. To receive credit: 90 % presentation, prepare exercise reports and pass the final test. The course continues in a summer term as B81479, focused on properties of impression materials.
Annotation
The course is focused on measurement and evaluation of the most important properties of restorative materials, such as polymerization depth of a composite materials and light curing glass-ionomer cements and how these properties are affected by a polymerization lamp (light intensity, type of lamp-LED, halogen). In the following lessons temperature changes in the tooth tissues during light polymerization will be recorded, mechanical properties e.g. strength and hardness (Istron, Indentamet measuring devices) of various materials (amalgam, composite, cement) will be characterized on model specimens and compared with hardness of human enamel and dentin.
You will have a chance to work with different brands of composite and other restorative materials (ZnO-phosphate, amalgam). Evaluation of the effect of glass-ionomer surface protection on its disintegration and measurement of polymerization contraction using Archimedes method will be also included.
In one of the exercises you will see various problems associated with a tooth shade determination, etc.