Bond strength of resin composites to cavity floor and cavity wall dentin

Takako Yoshikawa, DDS, PhD (1), Alireza Sadr, DDS, PhD (2), Makoto Arakawa, DDS, PhD (3), and Junji Tagami, DDS, PhD (1)

(1) Cariology and Operative Dentistry, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan, (2) IB3T Laboratory, Department of Restorative Dentistry, School of Dentistry, University of Washington, Seattle, WA, USA, and (3) Department of Dental Hygiene, Chiba Prefectural University of Health Sciences, Chiba, Japan



Purpose: To evaluate the effect of dentin location and dentinal tubule orientation on resin composite bond strength to dentin of the cavity floor and cavity wall using various adhesive systems.
Materials and Methods: Box-form cavities were prepared on human molars. Each specimen was restored with one of three adhesives Clearfil SE Bond, Single Bond, or Clearfil tri-S Bond followed by filling or buildup using Z100 resin composite. After light-curing at 600 mW/cm2 for 40 s, the specimen was cut perpendicular to the bonded surface parallel to the floor or wall to obtain beams. The microtensile bond strength to the cavity floor or wall specimens was determined. Data were analyzed using the Bonferroni test.
Results: Single Bond and Clearfil tri-S Bond showed significantly lower bond strength to the cavity floor compared with that of the cavity wall (p < 0.05). However, there was no significant difference in bond strength between the cavity floor and wall using Clearfil SE Bond (p > 0.05). Clearfil SE Bond showed significantly higher bond strength to the cavity floor than that of Single Bond and Clearfil tri-S Bond (p > 0.05).
Conclusion: Single Bond and Clearfil tri-s Bond bond strength to the cavity floor dentin was lower than to the cavity wall dentin. However, there was no significant difference in bond strength between the cavity floor and cavity wall using Clearfil SE Bond.
(Asian Pac J Dent 2016; 16: 23-28.)
Key Words: bond strength, dentin location, dentinal tubule orientation, resin composite