Objectives: To determine the effects of contamination
with whole blood on the bond strength of composite bonded to moist superficial
dentin using two different adhesive systems, Clearfil SE Bond (CB) and Clearfil
SE Bond Plus (CBP). Methods: Freshly extracted human teeth were
sectioned bucco-lingually and embedded in potting resin. Specimens were ground
to superficial dentin using 600 grit SiC discs. Adhesives were bonded according
to the manufacturer’s instructions using 5 surface conditions: Control (C), blood/5
sec air dry/adhesive (BA), adhesive/ blood/5 sec air dry (AB), adhesive/blood/5
sec water rinse/5 sec air dry (ABW), and adhesive/blood/5 sec water rinse/5 sec
air dry/reapply adhesive (ABWA). Clearfil AP-X was bonded in the form of a
truncated cone (bonding diameter of 3mm, height of 5 mm) for a total of 80
specimens. After bonding, specimens were stored in water at 37°C at 100% humidity for 24 hours. Specimens
were de-bonded in tension using an Instron at a cross-head speed of 0.5mm/min. Results:
Means and standard deviations (MPa) are shown in the table (n=8). Fisher's
PLSD intervals for comparisons of means between 2 adhesives and 5 treatments
|
Procedure
|
C
|
BA
|
AB
|
ABW
|
ABWA
|
|
CB
|
23.9 (6.0)
|
17.7 (5.8)
|
13.5 (3.0)
|
20.1 (5.6)
|
16.7 (3.7)
|
|
CBP
|
30.3 (6.2)
|
23.0 (8.5)
|
16.5 (4.4)
|
23.3 (6.5)
|
25.9 (6.7)
|
at the 0.05 level of significance were 2.6 and 4.1 MPa,
respectively. Failure sites were mixed. Conclusions: With both adhesives,
C had the highest and AB the lowest bond strength. CBP had higher bond
strengths than CB for all 5 surface conditions. In most cases after adhesive is
applied, if the surface is rinsed after blood contamination, control bond
strengths are regained. Funded by Kuraray America.