Influence of a simulated oral environment on dentin bond strength of two adhesive systems.
OBJECTIVE
To evaluate in vitro the influence of different clinical conditions (temperature, relative humidity) on dentin bond strength.


METHODS
Two different bonding systems were studied, ScotchBond Multi-Purpose Plus (SBMP) and Clearfil SE Bond (SE Bond). In the first part of the study, the different environmental conditions were: ambient conditions, i.e. 20 degrees C/30% relative humidity (RH), 30 degrees C/50% RH, 30 degrees C/65% RH, 33 degrees C/80% RH and 35 degrees C/95% RH. In the second part, the different interfaces (dentin/primer, primer/adhesive and adhesive/composite for SBMP and primer/adhesive, adhesive/composite for SE Bond) were also studied in order to explain the results obtained in the first part of the study. After the bonding procedure, a composite cylinder (Z100) was bonded to the surface using a Teflon mold (diameter: 3 mm/height: 5 mm). The different specimens were tested in a shear bond mode after a 24-hour storage in distilled water at 37 degrees C.


RESULTS
For SBMP, the shear bond strengths decreased when temperature/RH increased. The average values were very low when the 35 degrees C/95% RH conditions were simulated. A study of the interfaces showed that the primer/adhesive interface was the most sensitive to the environmental conditions simulated. For SE Bond, a decrease occurred but only at the highest temperature/humidity conditions. The interface study did not provide an explanation of the results obtained in the first part of the study.
Besnault
C
C
Biomaterials Research Group, Faculty of Dentistry, University Paris V, Montrouge, France. cath.besnault@wanadoo.fr
Attal
J P
JP
D000704:Analysis of Variance; D003188:Composite Resins; D001840:Dental Bonding; D003804:Dentin; D003806:Dentin Permeability; D017220:Dentin-Bonding Agents; D006801:Humans; D006813:Humidity; D008422:Materials Testing; D009055:Mouth; D011897:Random Allocation; D019279:Resin Cements; D012822:Silicon Dioxide; D013314:Stress, Mechanical; D013696:Temperature; D013718:Tensile Strength; D015040:Zirconium
C438313:Clearfil SE Bond; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D019279:Resin Cements; C425844:Scotchbond Multi-Purpose Plus; C083568:Z100 composite resin; D012822:Silicon Dioxide; D015040:Zirconium