Tensile Strength and Microscopic Adhesion Observation of Dental Composite Restorative Material Manufactured From Sisal Nanofiber as Filler

Abstract

Background: Dental Composite consists of inorganic filler material that does not have chemical adhesion to organic materials. Tooth structure and adhesive materials contained many organic materials. Inorganic fillers could be substituted by organic material. This material was sisal fiber. These fibers were hard and used as mechanical amplifiers to the matrix resin. This study manufactured dental composite with sisal nanofibers as the filler. Objective: This study investigated the microscopic adhesion between dental composite made from sisal nanofibers to tooth structure which was tested by tensile strength. Materials and Methods: Sisal fiber was converted into nano-sized. It was mixed with BisGMA (Sigma Aldrich), UDMA (Sigma Aldrich), TEGDMA (Sigma Aldrich), Champhorquinone (Sigma Aldrich). Composite Z350 XT (3M ESPE) was utilized as control. We used ten cone-shape samples (4 x 4 x 2 mm). They were divided into 2 groups namely sisal nanofibers composite labeled as group A; Z350 XT as group B. Extracted premolar teeth were filled using samples with the total-etch adhesive (3M ESPE). The samples were investigated using a Scanning Electron Microscope (SEM) (JSM-6510LA) and their tensile strength was tested using a Universal Testing Machine (Vertical test ASL-S). The data were processed by Independent Sample T-Test analysis. Results: The mean of the tensile strength of group A was 4.39 MPa, and that of group B was 1.23 MPa. There was a significant difference (p = 0.004; p < 0.05). SEM observation showed that there was no gap between the tooth structure with composite group A. Conclusion: Group A had better adhesion to tooth structure than group B and adequate tensile strength.