The purpose of this study was to evaluate the effect of moistening and air-drying of acid conditioned dentin and enamel on the marginal microleakage. In this study. Class V cavity were prepared on both buccal and lingual surface of sixty
extracted
human
premolars with cementum margin. These specimens were randomly devided into three groups and three dentin adhesives(Scotchbond Multi-Purpose, All bond 2, Prisma Universal Bond 3) were applied to each group.
The specimens in each group were subdevided into four groups(Wet/primed, Dry/primed, Wet/not primed, Dry/not primed) and the etched dentin and enamel surface were treated these four surface treatments prior to the placement of a bonding agent or
adhesive.
Wet/primed group was simply blot-dried with a damp facial tissue before primer placement; Dry/primed group was air dried for 30 seconds before the placement of a primer ; Wet/not primed group and Dry/not primed group were not primed after blot
dried and
air dried for 30 seconds each group.
The bonding agent and composite resin were applied for each group. All specimens were exposed to 500 cycle of thermal stress. Specimens were placed in a silver nitrate solution and then sectioned buccolingually through the center of the
restoration. The
dye penetrations of the specimens were observed with a stereomicroscope. The statistical test were applied to the results using a one way analysis variance (ANOVA) and Duncan's multiple range test. The aspects of silver ion penetration into the
resin/dentin interface were examined under scanning electron microscopy.
@ES The results were as follows.
@EN 1. In all groups, the enamel margin showed significantly lower leakage value than the cementum margin (p<0.05).
2. Regardless of various surface treatment and dentin adhesives, there was no significant difference at the enamel margins(p>0.05).
3. At the dentin margins, the leakage values of Dry/not primed group showed significantly higher than that of the other groups(p<0.05). The leakage values of Wet/primed group showed significantly lower than that of the other groups but, there
was
no
significant difference between Wet group and Dry group.
4. There was no significantly difference between the dentin adhesives regarding the surface treatments in all groups(p>0.05).
5. On the backscatterd scanning electron microscopy observation, the penetration of the silver ion occured at the bonding resin/dentin interface. In the Wet/kprimed group, resindentin hybrid zone and resin penetration into the dentin was
observed.
The
resin tags were compactively formed to a thickness of 3∼4㎛at the upper part of dentinal tubules. In the Dry/primed group, the thickness of the hybrid zone and the diameter, depth of the resin tags diminished. In the Non-primed groups, the
hybrid
zone
was not identified and few resin tag was observed. There was the gap formation in the resin/dentin interface.
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