The effect of bonding layer thickness of Tokuyama Bond Force

Objectives: To evaluate the effect of the bonding layer thickness on the dentin micro tensile bond strength of seven adhesives including Tokuyama Bond Force.

Methods: Resin composite (Estelite flow quick / Tokuyama Dental) was bonded to bovine dentin prepared with 600-grit SiC paper using various adhesives; BF: Bond Force and OBFP: One-up Bond F Plus (Tokuyama Dental), TS: S³ Bond and SE: SE Bond (Kuraray), X4: XenoIV (Dentsply), iB: i Bond (Heraeus Kulzer), and OP: OptiBond All-In-One (Kerr). The bonding layer thickness was controlled by the level of air blow. After bonding, the specimens were stored in water at 37 ^oC for 24 hours. Specimens were sectioned into 0.7-mm thick slabs and then trimmed to a cross-section area of 1 mm². The micro tensile bond strength was measured using a testing machine at a cross-head speed of 0.5 mm/min.

Results: Means (sd, n=6) of bond strength (MPa) are summarized in a table. The bond strength of OBFP, X4, and SE decreased when the bonding layer thickness was thin. On the other hand, the bond strength of BF was more than 50 MPa over the entire range of the bonding layer thickness from 1 to 50 um.

Conclusions: The bonding layer thickness did not affect the bond strength of Tokuyama Bond Force.