IADR Abstract Archives
Ultra-morphological Analysis of Universal Adhesives on Dentin: Self-etch vs Etch-and-rinse
Objectives: To study the ultra-morphology of dentin-resin interfaces formed with universal adhesives (UAs) applied in self-etch (SE) and etch-and-rinse (ER) mode.
Methods: Middle dentin of 24 extracted human molars was exposed with a diamond saw under water irrigation. Specimens were randomly assigned to one of six UAs: (1) All-Bond Universal (AB, Bisco); (2) Adhese Universal (AD, Ivoclar Vivadent); (3) Clearfil Universal Bond (CU, Kuraray Noritake); (4) Futurabond Universal (FU, Voco); (5) Prime&Bond Elect (PE, Dentsply Sirona); (6) Scotchbond Universal (SU, 3M Oral Care). For each UA, 2 teeth were treated in SE mode and 2 teeth in ER mode following the respective manufacturer’s instructions. A 1-mm layer of flowable composite was applied and light-cured for 40 sec. After fixation in Karnovsky solution and dehydration in ascending grades of ethanol followed by HMDS, the resin-dentin interfaces were decalcified with 6N HCL for 30 sec and deproteinized with 2.5% NaOCl for 10 min. After thoroughly rinsing with distilled water, specimens were embedded in epoxy resin, sectioned and processed for FESEM observation by sputter-coating with Au-Pd. Observation was carried out under a Hitachi S-4700 FESEM.
Results: In SE mode, all UAs resulted in an intact submicron hybrid layer (HL), with micro resin tags and resin-infiltrated smear plugs.
In ER mode, AB and AD formed a densely packed HL with well-defined lateral peritubular triangular hybridization and resin tag hybridization. For CU, FU, PE, and SU, besides areas of apparently fully-infiltrated HL, there were areas with deficient hybridization that was depleted of the characteristic fibrillar pattern of the HL. These areas of incomplete adhesive infiltration resembled a ghost-hybrid layer
Conclusions: None of the UAs was able to fully infiltrate dentin simultaneously in both SE and ER modes.
The SE mode resulted in tighter interfaces in comparison with the ER mode.
Methods: Middle dentin of 24 extracted human molars was exposed with a diamond saw under water irrigation. Specimens were randomly assigned to one of six UAs: (1) All-Bond Universal (AB, Bisco); (2) Adhese Universal (AD, Ivoclar Vivadent); (3) Clearfil Universal Bond (CU, Kuraray Noritake); (4) Futurabond Universal (FU, Voco); (5) Prime&Bond Elect (PE, Dentsply Sirona); (6) Scotchbond Universal (SU, 3M Oral Care). For each UA, 2 teeth were treated in SE mode and 2 teeth in ER mode following the respective manufacturer’s instructions. A 1-mm layer of flowable composite was applied and light-cured for 40 sec. After fixation in Karnovsky solution and dehydration in ascending grades of ethanol followed by HMDS, the resin-dentin interfaces were decalcified with 6N HCL for 30 sec and deproteinized with 2.5% NaOCl for 10 min. After thoroughly rinsing with distilled water, specimens were embedded in epoxy resin, sectioned and processed for FESEM observation by sputter-coating with Au-Pd. Observation was carried out under a Hitachi S-4700 FESEM.
Results: In SE mode, all UAs resulted in an intact submicron hybrid layer (HL), with micro resin tags and resin-infiltrated smear plugs.
In ER mode, AB and AD formed a densely packed HL with well-defined lateral peritubular triangular hybridization and resin tag hybridization. For CU, FU, PE, and SU, besides areas of apparently fully-infiltrated HL, there were areas with deficient hybridization that was depleted of the characteristic fibrillar pattern of the HL. These areas of incomplete adhesive infiltration resembled a ghost-hybrid layer
Conclusions: None of the UAs was able to fully infiltrate dentin simultaneously in both SE and ER modes.
The SE mode resulted in tighter interfaces in comparison with the ER mode.