A COMPARATIVE EVALUATION OF COMPRESSIVE STRENGTH OF POSTERIOR
RESTORATIVE MATERIALS: AN IN VITRO STUDY
Abstract
BACKGROUND AND OBJECTIVES: The ‘Basic filling materials’ Amalgam and
glass ionomer have been well accepted for posterior restorations, but
have multifarious drawbacks such as low flexural strength, surface wear,
porosity of glass ionomer cements, intrinsic grey unaesthetic appearance
of amalgam, its inability to bond tooth and concerns about mercury
content. Hence, newer materials were introduced in the market with
better biomechanical properties. The present study aimed to evaluate and
compare the compressive strength of Ceramic-Reinforced Glass Ionomer
cement, Zirconia-Reinforced Glass Ionomer cement, High Strength Glass
Ionomer Posterior restorative material, Alkasite restorative material,
and Amalgam when used as posterior restorative materials. METHODOLOGY:
Fifty cylindrical specimens measuring 6mm in height and 4mm in diameter
were fabricated using test materials. Class II cavity was prepared on
fifty intact permanent human molar teeth and randomly divided into five
groups based on the material to be filled with ten specimens each: Group
1- Ceramic-Reinforced Glass Ionomer cement, group 2- Zirconia-Reinforced
Glass Ionomer cement group 3- High Strength Glass Ionomer Posterior
restorative material group 4- Alkasite restorative material and group 5-
amalgam. All the specimens were thermocycled and stored in artificial
saliva for 24 hours. The specimens were subjected to compressive
strength testing using Universal Testing Machine (Zwick Roell, Z020,
Zwick, Ulm, Germany). Data were analyzed statistically using IMB SPSS
Statistics, Version 22 (Armonk, NY: IBM Corp). RESULTS: The present
study reveals a significantly high compressive strength of cylindrical
specimens of Group 4, followed by Group 5, Group 3, Group 1, and least
by Group 2. The highest maximum compressive load was supported by teeth
restored with the material of Group 4, Group 1, Group 5, Group 2, and
least by Group 3. CONCLUSION: Within the limitations of the study,
alkasite restorative material showed the highest compressive strength in
cylindrical and tooth specimens.