IADR Abstract Archives
Protocols of Dentin Biomodification With Chitosan to Improve Bond Strength
Objectives: The use of biopolymers such as chitosan solution can improve the chemical and mechanical properties of the adhesive interface. This study evaluated the shear bond strength (SBS) of restorative material to dentin pretreated with chitosan solution at different protocols of application.
Methods: Seventy bovine slabs of dentin (5 x 5 x 3mm) were embedded in acrylic resin and polished. The specimens were etched with 37% phosphoric acid, rinsed and then randomly divided into 7 groups (n=10) according to the biomodification protocol: G1. No treatment (control), G2. Application of 0.2% chitosan solution, aspiration and drying, G3. Application of 0.2% chitosan solution, washing and drying, G4. Application of 1.0% chitosan solution, aspiration and drying, G5. Application of 1.0% chitosan solution, washing and drying, G6. Application of 2.0% chitosan solution, aspiration and drying, G7. Application of 2.0% chitosan solution, washing and drying. All solutions were applied onto surface for 1 min. The surface were restored with adhesive (Adper Single Bond 2 /3M) and composite resin (Filtek Z250/3M) using a split matrix. Data were analyzed by ANOVA and Tukey test (α=0.05). Failures were assessed under SEM.
Results: The specimens of G7 (treated with 2.0% chitosan followed by washing and drying) had the highest SBS means (p<0.05). The other protocols of application provided the same SBS of control group (p>0.05), without treatment. Adhesive failures were predominant in all groups expect for those treated with 2.0% chitosan, in which mixed failures were most frequent.
Conclusions: The application of chitosan solution at 2.0% followed by washing and drying create a dentin substrate more favorable to the adhesion of composite resin.
Methods: Seventy bovine slabs of dentin (5 x 5 x 3mm) were embedded in acrylic resin and polished. The specimens were etched with 37% phosphoric acid, rinsed and then randomly divided into 7 groups (n=10) according to the biomodification protocol: G1. No treatment (control), G2. Application of 0.2% chitosan solution, aspiration and drying, G3. Application of 0.2% chitosan solution, washing and drying, G4. Application of 1.0% chitosan solution, aspiration and drying, G5. Application of 1.0% chitosan solution, washing and drying, G6. Application of 2.0% chitosan solution, aspiration and drying, G7. Application of 2.0% chitosan solution, washing and drying. All solutions were applied onto surface for 1 min. The surface were restored with adhesive (Adper Single Bond 2 /3M) and composite resin (Filtek Z250/3M) using a split matrix. Data were analyzed by ANOVA and Tukey test (α=0.05). Failures were assessed under SEM.
Results: The specimens of G7 (treated with 2.0% chitosan followed by washing and drying) had the highest SBS means (p<0.05). The other protocols of application provided the same SBS of control group (p>0.05), without treatment. Adhesive failures were predominant in all groups expect for those treated with 2.0% chitosan, in which mixed failures were most frequent.
Conclusions: The application of chitosan solution at 2.0% followed by washing and drying create a dentin substrate more favorable to the adhesion of composite resin.