Scanning electron microscopy evaluation of the marginal gap in composite restorations with different adhesive techniques


  • Fábio Herrmann Coelho-de-Souza
  • Celso Afonso Klein-Júnior
  • Leonardo Maciel Campos
  • Michele Kleina
  • Elisabeth Pereira
  • Natália Fernandes Fischer


Composite resin, dentin-bonding agents, scanning electron microscopy


Purpose: This study used scanning electron microscopy (SEM) to evaluate the gap formation in composite restorations with four adhesive techniques: Prime & Bond 2.1 (Dentsply) without etching, Prime & Bond 2.1 with conventional etching, Prime & Bond 2.1 with 25% polyacrylic acid conditioning, and Clearfil SE Bond (Kuraray). Methods: Five extracted sound human third molars were used. Four cavities were prepared in each tooth and restored with Z250 (3M/ESPE) composite resin, using each of the four adhesive techniques tested. Teeth were termocycled for 500 cycles and evaluated in SEM to measure gap formation in the gingival walls. Results: No significant difference of marginal gap was found among the four experimental groups of adhesive techniques (ANOVA, P>0.05). Conclusions: None of the tested adhesive techniques was able to avoid marginal gap formation; there was no difference among the adhesive techniques. Key words: Composite resin; dentin-bonding agents; scanning electron microscopy




Original Article