Assessment of Occlusal Load Strength of Glass Ionomer Cement and Composite in Class V Cavities: An In-Vitro Study.

BACKGROUND:  Glass ionomer cement (GIC) is widely used in dentistry due to its chemical adhesion to dental tissues, biocompatibility, and anti-cariogenic potential but they have relatively weak mechanical properties. Resin composites have been widely regarded as the first choice for direct restorations but their polymerization shrinkage has remained a major problem. It has the potential to cause tooth debonding. The composite interface leads to postoperative sensitivity, secondary caries, enamel cracks, and microleakage. A restorative material's capacity to withstand occlusal stresses and support the remaining tooth structure depends on this property. Although class V restorations are predominantly done with GIC, this study was done to compare the strength of composite with the same. The GIC restore glass which is commonly used was tested against restofill composite. The main objective of conducting the study was to compare the compressive strength of the composite vs GIC in cervical cavities. So the aim of the study is to assess the occlusal load strength of GIC and composite in class V cavities using the universal testing machine.

MATERIALS AND METHODS:  This study was employed as an in vitro study involving 20 natural central incisor teeth without any carious lesions. Class V cavity preparation was done and the selected teeth were divided into two groups of ten each. The cavities were filled with D Tech Restore GIC and composite restorations (restofill), respectively, polished, and then subjected to testing. An eccentric load was applied to the tooth structure using an Instron (Instron E3000 Electropuls, Instron, Norwood, United States) - Universal testing machine with a cross-head speed of 1mm per minute, and the stresses were further analyzed in the presence of an occlusal loading test using a stainless steel jig of 1mm diameter which led to the sectioning of the tooth buccolingually under the applied load.

RESULTS:  An independent t-test was used to assess the results, and it was concluded that the results were statistically significant (p<0.05) at p=0.034.

CONCLUSION:  Conclusively, the results suggested that the occlusal load strength of the composite is greater when compared to GIC.