How Water Content Can Influence the Chemomechanical Properties and Physical Degradation under Aging of Experimental Adhesives.

Tiago Moreira Bastos Campos,Tânia Mara da Silva,Mateus Rodrigues Silva,Carlos A. Munoz-Viveros,Sérgio Eduardo de Paiva Gonçalves,Daphne Camara Barcellos,César Rogério Pucci,Stella Renata Machado Silva Esteves,Elizabeth Pimentel Rosetti

doi:10.1155/2022/5771341

Abstract

Objective To evaluate the physicochemical (sorption (SOR), solubility (SOL), and degree of conversion (DC)) and mechanical (flexural strength (FS), modulus of elasticity (ME), and compressive strength (CS)) properties of adhesives with different water contents (D2O). Materials and Methods An adhesive was formulated: 55 wt% BisGMA, 45 wt% HEMA, 0.5 wt% camphorquinone, 0.5 wt% EDMAB, and 1.0 wt% DPIHP. D2O was added into the adhesives (0 wt%, 10 wt%, and 16 wt%). DC was monitored through the FTIR. FS, ME, CS, SOR, and SOL were tested. The adhesive samples were aged in deionized water, ethanol, and acetone. Data were submitted to ANOVA and Tukey's tests (5%). Results For DC, the 0 wt% group showed a significant reduction (68.09 ± 0.14A) compared with the 10 wt% (87.07 ± 0.81B) and 16 wt% groups (89.87 ± 0.24B); 10 wt% showed the highest FS (MPa) mean values (141.6 ± 6.71B) compared with the 0 wt% (109.4 ± 20.5A) and 16 wt% (107.8 ± 15.8A). For the CS (MPa) and ME (GPa), the 16 wt% showed the lowest mean values (98.8 ± 18.0B and 2.2 ± 0.3B, respectively) compared with the 10 wt% and 0 wt%. For the SOR, 16 wt% of water showed the highest mean values and the ethanol showed the lowest mean values of SOL regardless of water content. Conclusion The amount of water content and the types of aging solvents significantly affect the adhesive properties.

Highlights

Failures of composite restorations are observed mainly at the dentin/ adhesive interface. e factor for the long-term success of the composite restoration is the integrity of the adhesive bond layer with the presence and quality of the hybrid layer [2]
E factors that limit the durability of the adhesive layer are incomplete polymerization, partial infiltration of the adhesive into the demineralized dentin matrix, phase separation, and hydrolytic degradation of the adhesive interface [3]
International Journal of Dentistry inside the adhesive, and phase separation at the adhesive/ dentin interface has appeared as a new type of bond defect [5], dilutes the hydrophilic adhesive monomer and plasticizer polymer, and accelerates degradation of the adhesive interface [6]

Summary

Objective

To evaluate the physicochemical (sorption (SOR), solubility (SOL), and degree of conversion (DC)) and mechanical (flexural strength (FS), modulus of elasticity (ME), and compressive strength (CS)) properties of adhesives with different water contents (D2O). FS, ME, CS, SOR, and SOL were tested. E adhesive samples were aged in deionized water, ethanol, and acetone. For DC, the 0 wt% group showed a significant reduction (68.09 ± 0.14A) compared with the 10 wt% (87.07 ± 0.81B) and 16 wt% groups (89.87 ± 0.24B); 10 wt% showed the highest FS (MPa) mean values (141.6 ± 6.71B) compared with the 0 wt% (109.4 ± 20.5A) and 16 wt% (107.8 ± 15.8A). For the SOR, 16 wt% of water showed the highest mean values and the ethanol showed the lowest mean values of SOL regardless of water content. E amount of water content and the types of aging solvents significantly affect the adhesive properties Conclusion. e amount of water content and the types of aging solvents significantly affect the adhesive properties

Introduction

Materials and Methods

Degree of

Flexural Strength and Modulus of Elasticity

Compressive Strength

Results