M. KIMURA, Q. CUI, A. DODOMI, K. MATSUSHIGE, and H. KAZAMA, Tokuyama Dental Corporation, Tsukuba, Japan |
Objectives: To evaluate
the adaptation to step-form cavity of three adhesives including Tokuyama Bond
Force. Methods: The step-form cavity (4-mm diameter/3-mm depth + 2-mm
diameter/1.5-mm depth) was prepared with fresh bovine teeth by using a diamond
bur. Tokuyama Bond Force (BF/Tokuyama Dental), S3 Bond (S3/Kuraray),
and SE Bond (SE/Kuraray) were used. The adhesives were applied to the cavity
walls following the manufacturer's instructions. Subsequently, resin composite
(Estelite Flow Quick/Tokuyama Dental) was filled in the cavity and polymerized
by light irradiation followed by Estelite Sigma (Tokuyama Dental). The
specimens were kept in water at 37 oC for 24 hours. The specimens
were cut along the symmetrical axis to expose the cross-section of
teeth/adhesive. The cross-section was polished to a high gloss with diamond
pastes (grit 6, 3, 1, 1/4 um) and observed by using laser microscope
(VK9700/KEYENCE). Results: In BF, a
uniform thin bonding layer was formed even around the corner and the edge part. The bonding layer is
combined with resin composite and the cavity wall remarkably. In SE, the bonding
layer is combined with resin composite and the cavity wall tightly. However,
the bonding layer is thick especially around the corners. In S3, the bonding
layer is thick especially around the corners. The slight abrasion in the
bonding layer after being polished was observed.
Adhesives | Bonding layer thickness | around the corner / um | at cavity floor / um | BF | 11.6 - 13.3 | 10.7 - 12.3 | S3 | 35.0 - 107.1 | 21.5 - 24.2 | SE | 326.0 - 600.6 | 58.9 - 163.3 |
Conclusion: BF showed excellent adaptability to the
step-form cavity.
|