Resin/Resin bonding: a new adhesive technology.
OBJECTIVE
Evaluation of a new surface treatment method to obtain a good bond strength between a luting composite and (1) a light-cured, (2) a heat-cured and (3) a thermoplastic resin.


METHODS
Specimens were prepared and tests conducted according to ISO 10477, Amend. 1. The surfaces of Targis (light cured), SR Isosit (heat cured), and Dental D (thermoplastic) were ground under water cooling with 400-grit grinding paper, polished with 800-grit paper and air dried. Each resin material was divided into 3 groups of 10 specimens each. Group 1 was flame treated with a PyrosilPen for 5 s/2 cm2, group 2 for 10 s/2 cm2, and group 3 for 20 s/2 cm2. Subsequently, a methacryl silane was applied, followed by a luting composite. Prior to measuring shear bond strength, the specimens were thermocycled 5000 times in a water bath between 5 degrees C and 55 degrees C. SEM, FTIR investigations, and fracture analysis were also done. Etched and silanized Empress II - the gold standard - was used as a control.


RESULTS
The following shear bond strengths were found: treatment time 5 s/2 cm2, Targis 25 (+/- 12) MPa, SR Isosit 17 (+/- 11) MPa; treatment time 10 s/2 cm2, Targis 23 (+/- 12) MPa, SR Isosit 26 (+/- 8) MPa; treatment time 20 s/2 cm2, Targis 29 (+/- 5) MPa, SR Isosit 26 (+/- 9) MPa. All Dental D specimens failed completely so that shear bond strength could not be measured. The control achieved 27 (+/- 6) MPa. No significant differences were found between the materials or the flaming times. On all flamed surfaces, Si was detected by FTIR. SEM showed that no heat destruction occurred at a flaming time of 5 s/2 cm2, a slight change at 10 s/2 cm2, and a significant change at 20 s/2 cm2.


CONCLUSIONS
This new bonding technology is an effective method for surface-treating polymerized composite resin materials to obtain good bonding to luting composites. The method fails on thermoplastic resins.
Janda
Ralf
R
Dept. of Operative and Preventive Dentistry and Endodontics, Faculty of Medicine (Charité), Humboldt University, Berlin, Germany. rjanda1108@aol.com
Roulet
Jean-François
JF
Wulf
Michael
M
Tiller
Hans-Jürgen
HJ
D000180:Acrylic Resins; D003188:Composite Resins; D001840:Dental Bonding / Q000295:instrumentation* / Q000379:methods*; D005899:Glass Ionomer Cements; D006358:Hot Temperature; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011091:Polyesters; D011140:Polyurethanes; D019279:Resin Cements; D012117:Resins, Synthetic; D033081:Shear Strength; D012821:Silanes; D012823:Silicate Cement; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties
D000180:Acrylic Resins; C029012:Composite Dental Resin; D003188:Composite Resins; C474195:Dental D; D005899:Glass Ionomer Cements; D011091:Polyesters; D011140:Polyurethanes; D019279:Resin Cements; D012117:Resins, Synthetic; D012821:Silanes; C111282:dental polyglass; D012823:Silicate Cement; C103502:Variolink; C513704:Isosit; C010102:delrin