Influence of luting agent on the microleakage of all-ceramic crowns.
OBJECTIVE
In this in-vitro study, microleakage of all-ceramic crowns was evaluated at enamel and dentin margins.


METHODS
Forty maxillary central incisors were randomly divided into 4 groups (n = 10). While buccal and palatal margins were placed on enamel, mesial and distal margins were placed below the cementoenamel junction. In groups 1 to 3, IPS Empress 2 crowns were luted with Variolink 2/Syntac Classic (group 1), Bifix DC/Solobond Plus (group 2) and Calibra/Prime & Bond NT combinations (group 3), respectively. In the control group (group 4), porcelain-fused-to-metal crowns were luted with a zinc-phosphate cement. All specimens were subjected to 5000 thermocycles (at 5 degrees C to 55 degrees C; 30-s dwell time). After immersion in India ink for 48 h at 37 degrees C, the specimens were sectioned both buccolingually and mesiodistally. Each section was evaluated for microleakage under a stereomicroscope at 24X magnification.


RESULTS
According to the Krukal-Wallis test, in all groups, there were significant differences in microleakage at the enamel margins (p = 0.001). Nevertheless, the margins finished in dentin showed no significant differences (p = 0.163). According to the Mann-Whitney U-test, statistically significant differences were observed in microleakage between groups 1 and 3 (p = 0.049), groups 1 and 4 (p = 0.001), groups 2 and 4 (p = 0.002), and between groups 3 and 4 (p = 0.045) at the enamel margin. In group 1, significantly greater microleakage was observed at the dentin margin compared to the enamel margin (p = 0.007).


CONCLUSIONS
The adhesive luting technique demonstrated an excellent ability to minimize microleakage of all-ceramic crowns at the enamel margins. Water-based dentin bonding systems showed less microleakage than the water-free acetone-based dentin bonding system at the enamel margin.
Toman
Muhittin
M
Department of Prosthetic Dentistry, Faculty of Dentistry, Ege University, Izmir, Turkey. tomantr@yahoo.com
Toksavul
Suna
S
Artunç
Celal
C
Türkün
Murat
M
Schmage
Petra
P
Nergiz
Ibrahim
I
D000096:Acetone / Q000737:chemistry; D002244:Carbon; D004396:Coloring Agents; D003188:Composite Resins / Q000737:chemistry; D003442:Crowns; D003743:Dental Enamel / Q000648:ultrastructure; D003763:Dental Leakage / Q000145:classification*; D003776:Dental Porcelain / Q000737:chemistry*; D003804:Dentin / Q000648:ultrastructure; D006801:Humans; D018020:Lithium Compounds / Q000737:chemistry; D008422:Materials Testing; D016876:Metal Ceramic Alloys / Q000737:chemistry; D008689:Methacrylates / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D019237:Tooth Cervix / Q000648:ultrastructure; D014867:Water / Q000737:chemistry; D015036:Zinc Phosphate Cement / Q000737:chemistry
C515607:Bifix composite; C433205:Calibra; D004396:Coloring Agents; D003188:Composite Resins; C118557:Empress 2; D018020:Lithium Compounds; D016876:Metal Ceramic Alloys; D008689:Methacrylates; D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; D019279:Resin Cements; C488002:Solobond Plus adhesive; D012997:Solvents; C078484:Syntac dentine adhesive; C028433:chinese ink; D014867:Water; D003776:Dental Porcelain; D000096:Acetone; C103502:Variolink; D002244:Carbon; D015036:Zinc Phosphate Cement