A Comparative Evaluation of Sealing Ability and Diametral Tensile Strength of two Pulp Capping Materials “ Sodium Hexa Meta Phosphate SHMP and Mineral Trioxide Aggregate MTA”: An in Vitro Study

Abstract

Background: Indirect pulp capping is a preventative procedure that keeps the pulp alive by sealing the remaining damaged dentin with a bioactive substance. Mineral trioxide aggregate (MTA) is frequently utilised, however, its limitations have prompted the development of alternative materials such as sodium hexametaphosphate (SHMP). Aim of the study: To investigate and compare the sealing ability and diametral tensile strength (DTS) of SHMP and MTA as indirect pulp capping materials. Materials and Methods: Sealing ability was evaluated using methylene blue dye penetration and stereomicroscope in 24 extracted human permanent premolars (n=12/group). DTS was assessed using 20 disc-shaped specimens (n=10/group) with a universal testing machine. Statistical analysis was carried out with the Mann-Whitney U test (p < 0.05). Results: SHMP demonstrated significantly better sealing ability than MTA, with lower dye penetration scores (0.83 ± 1.11 vs. 2.75 ± 0.87; p = 0.0003). SHMP also showed significantly higher DTS than MTA (1.171 ± 0.217 MPa vs. 0.736 ± 0.309 MPa; p = 0.0109). Conclusion: Given the constraints of this in vitro investigation, SHMP exhibited enhanced sealing capability and diametral tensile strength relative to MTA, indicating its potential as an advantageous pulp capping substance.