Repairability of cross-linked biopolymers.
Repair of biopolymers is a critical issue, especially with aged restorations. Obtaining a chemical bond to the repair surface might solve this problem. We hypothesized that certain repair liquids are suitable to establish a strong bond to an artificially aged dimethacrylate-based biopolymer for temporary restorations. Specimens made of a self-curing temporary crown-and-bridge material were prepared and thermocycled for 7 days (5000x, 5-55 degrees C). Cylinders made of light-curing composites (n=10) were bonded onto the specimen surface, either after grinding or after the application of 4 different experimental repair liquids (Bis-GMA:TEGDMA mixture=bonding, methylmethacrylate=MMA, bonding & acetone, bonding & MMA). A shear bond strength test was performed 24 hrs after repair. The highest bond strength was obtained with the bonding & acetone liquid (20.1+/-2.2 MPa). The use of MMA significantly affected the bond strength (6.8+/-1.9 MPa). MMA is inadequate as a repair liquid on aged composite-based biopolymers.
Balkenhol
M
M
Department of Prosthetic Dentistry, Justus-Liebig-University, Schlangenzahl 14, D-35392 Giessen, Germany. markus.balkenhol@dentist.med.uni-giessen.de
Michel
K
K
Stelzig
J
J
Wöstmann
B
B
D000096:Acetone; D001704:Biopolymers / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003442:Crowns; D001840:Dental Bonding; D017269:Dental Prosthesis Repair; D003794:Dental Restoration, Temporary; D003799:Dental Stress Analysis; D003833:Denture, Partial, Temporary; D008422:Materials Testing; D020366:Methylmethacrylate; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D033081:Shear Strength; D013997:Time Factors; D014783:Viscosity; D017155:Wettability
D001704:Biopolymers; D003188:Composite Resins; D011109:Polymethacrylic Acids; D000096:Acetone; C020946:triethylene glycol dimethacrylate; D020366:Methylmethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate