Durability of four composite resin cements bonded to dentin under simulated pulpal pressure.
OBJECTIVE
This study aimed to investigate the durability of four adhesive luting systems bonded to dentin with and without simulated hydrostatic pulpal pressure (PP).


METHODS
Composite blocks were bonded to dentin with four adhesive systems: Multilink Automix (MA), Multilink Sprint (MS), Clearfil Esthetic cement (CE) and RelyX ARC (RAC) under either a PP of 0 or 15 cm H(2)O. After 3 d water storage at 37 degrees C or thermal cycling (TC), of 30 d with 5000 TC or 90 d with 15,000 TC micro-tensile bond strength (microTBS) was tested. Failure analysis of the bonding interface was performed using a scanning electron microscope (SEM).


RESULTS
Independent of PP application groups MA and RAC showed significantly higher microTBS than CE and MS (P< or =0.05). A significant decrease in microTBS was found for RAC and MS when subjected to PP (P< or =0.05), whereas CE and MA showed no significant difference (P>0.05). TC had no significant influence on the microTBS in RAC, MA and CE without PP application (P>0.05), whereas CE with PP and MS showed a significant decrease in microTBS (P< or =0.05) when subjected to TC.


CONCLUSIONS
Based on these results, there were significant differences between materials. Pulpal pressure and artificial aging also seem to have an effect on in-vitro evaluation of bonding durability. If considered relevant to the materials' service performance then these conditions should be applied in the materials' testing.
Lin
Jun
J
Department of Stomatology, First Affiliated Hospital, Faculty of Dentistry, Zhejiang University, Qin Chun Road 79, Hangzhou, China.
Mehl
Christian
C
Yang
Bin
B
Kern
Matthias
M
D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D003782:Dental Pulp / Q000502:physiology*; D003799:Dental Stress Analysis; D003804:Dentin; D006358:Hot Temperature; D006801:Humans; D006874:Hydrostatic Pressure; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013718:Tensile Strength
D019279:Resin Cements