Abstract:

BACKGROUND: Total-etch technology is often used to dentin caries, but there are postoperative sensitivities. Crystals can form in dentin tubules after oxalic acid iron solution is used on dentin.
OBJECTIVE: To study the micromorphological characteristics of dentin bonding interface after usage of 5.3% acid iron solution linking with total-etch technology to guide clinical therapy.
METHODS: Twelve extracted human molars which were eliminated enamel were divided into experimental group and control group. 5.3% acid iron solution was used to experimental group. According to the manufacturer instructions, Chrisma B20 was adhered to the dentin interfaces. All the ultrastructures of dentin bonding interfaces were observed with scanning electronic microscope.
RESULTS AND CONCLUSION: Most of the dentin tubules were occluded by crystal-like structures in experimental group. Lots of short resin protrusions walked from resin layer to harden dentin. In the teeth which were only used total-etching, there was obvious crack between local mixture layer and the dentin. Resin protrusions were thick and uneven. There was resin crack. 5.3% acid iron solution could product crystal-like structures in the dentin tubules. The resin tag was broken and the dentinal tubules were open in control group. Postoperative sensitivity of experimental group can be less than that of control group.