Tooth-composite bond failure with a universal and an etch-and-rinse adhesive depending on mode and frequency of application

Research output: Contribution to journalResearch articleContributedpeer-review


  • Ellen Schulz-Kornas - (Author)
  • Mathilde Tittel - (Author)
  • Hartmut Schneider - (Author)
  • Maximilian Bemmann - (Author)
  • Marco Pellino - (Author)
  • Tobias Meissner - (Author)
  • Florian Fuchs - (Author)
  • Christian Hannig - , Department of Dental Maintenance (Author)
  • Florian Tetschke - , Department of Dental Maintenance (Author)
  • Kyung-Jin Park - (Author)
  • Michaela Strumpski - (Author)
  • Rainer Haak - (Author)


OBJECTIVES: To evaluate the effect of an additional layer of universal adhesive on the interfacial enamel/dentin-composite gap formation in relation to application mode and aging, via spectral domain optical coherence tomography (SD-OCT) and scanning electron microscopy (SEM).

METHODS: In vitro class V cavities in 114 caries-free premolars were restored by applying one or two layers of a universal adhesive (Scotchbond Universal, SBU) in self-etch (se) and etch-and-rinse (er) mode or the reference adhesive OptiBond FL (OFL-er). The restorations were imaged by SD-OCT (six groups, n = 8) and SEM (n = 3) directly after filling (t1), water storage (t2, 24 h), embedding (t3), and thermo-mechanical loading (t4, TCML). The interfacial gaps were quantified using 26 parameters and analyzed using principal component analysis and linear mixed effect models.

RESULTS: Gap formation at enamel and dentin was significantly influenced by the adhesive, the application mode and number of layers (p < 0.001). This was due to the influence of the SBU-er mode (p < 1e-05), which showed significantly more gap formation and a greater range of variation with double application when compared to SBU-se and OFL. The fewest interfacial gaps occurred with one or two applications of OFL-er and one layer of SBU-er.

SIGNIFICANCE: Adhesive application mode and the number of adhesive layers are relevant factors in the tooth-composite bond failure. Double application worsened the adaptation of SBU to freshly prepared dentin conditioned with phosphoric acid.


Original languageEnglish
JournalDental materials : official publication of the Academy of Dental Materials
Publication statusE-pub ahead of print - 23 Dec 2023

External IDs

Scopus 85180592405