Subject(s)
Chromium Alloys , Dental Soldering , Gold Alloys , Diffusion , Surface Properties , Tensile StrengthSubject(s)
Chromium Alloys , Dental Soldering , Gold Alloys , Diffusion , Electron Probe Microanalysis , Surface PropertiesSubject(s)
Dental Materials , Absorption , Chemical Phenomena , Chemistry, Physical , Elasticity , Stress, Mechanical , Temperature , Time Factors , WaterABSTRACT
Bending tests corresponding to the German Industrial Norm 13,922 for plastic filling material were carried out with ultraviolet polymerized Nuva-Fil P.A. and photopolymerized Fotofil. The photopolymerized Fotofil fulfilled the German Industrial Norm requirements: at least 50 N/mm2 bending impact strength after 24 hours. After longer periods of time, however, bending impact strength dropped below 50 N/mm2. The difference between Fotofil and other composites was obvious. The use of Fotofil together with increased bending module led to increased brittleness.
Subject(s)
Composite Resins/standards , Dental Restoration, Permanent , HumansABSTRACT
The resistance to bending of paste-paste composites decreases with one exception after prolonged storage in water. The UV-hardened artificial filling materials show no uniform picture in this respect. The bending module of three paste-paste composites is at its peak after 24 hours with values of 40 to 50 kN/mm2, and then drops to 1/3 of this value. The value of the bending module of photopolymerising composites lies considerably lower-between 4 and 13 kN/mm2.
Subject(s)
Composite Resins , Stress, Mechanical , WaterABSTRACT
Mechanical firmness of 4 UV hardened composites was estimated by the bending test according to DIN 13922. Bending strength and breaking point lie between 70 and 120 MPA and 0.5 and 0.25 mm compared with 110 MPA and 0.13 mm for Adaptic. The results show that the combination of filling substance and UV irradiation is well balanced.
