Examination of Calcium Silicate Cements with Low-Viscosity Methyl Cellulose or Hydroxypropyl Cellulose Additive.

Toshiaki Baba,Yasuhisa Tsujimoto

doi:10.1155/2016/4583854

Abstract

The purpose of this study was to improve the operability of calcium silicate cements (CSCs) such as mineral trioxide aggregate (MTA) cement. The flow, working time, and setting time of CSCs with different compositions containing low-viscosity methyl cellulose (MC) or hydroxypropyl cellulose (HPC) additive were examined according to ISO 6876-2012; calcium ion release analysis was also conducted. MTA and low-heat Portland cement (LPC) including 20% fine particle zirconium oxide (ZO group), LPC including zirconium oxide and 2 wt% low-viscosity MC (MC group), and HPC (HPC group) were tested. MC and HPC groups exhibited significantly higher flow values and setting times than other groups (p < 0.05). Additionally, flow values of these groups were higher than the ISO 6876-2012 reference values; furthermore, working times were over 10 min. Calcium ion release was retarded with ZO, MC, and HPC groups compared with MTA. The concentration of calcium ions was decreased by the addition of the MC or HPC group compared with the ZO group. When low-viscosity MC or HPC was added, the composition of CSCs changed, thus fulfilling the requirements for use as root canal sealer. Calcium ion release by CSCs was affected by changing the CSC composition via the addition of MC or HPC.

Highlights

Root canal fillings can seal the content of the root canal system, thereby preventing the egress of microorganisms or byproducts into periradicular tissues
Both the methyl cellulose (MC) and hydroxypropyl cellulose (HPC) groups exhibited a significantly higher flow value compared with the Mineral trioxide aggregate (MTA) and zirconium oxide (ZO) groups (p < 0.05), with flow values above 17 mm, which is the reference value according to ISO 6876-2012 (Table 3)
There was no significant difference between the MC and HPC groups

Summary

Introduction

Root canal fillings can seal the content of the root canal system, thereby preventing the egress of microorganisms or byproducts into periradicular tissues. An ideal root canal filling material should be biocompatible, antibacterial, nontoxic, and radiopaque and should not be resorbable or soluble in an oral environment [1]. The material should be costeffective, easy to handle, and closely adaptable to the cavity walls. Mineral trioxide aggregate (MTA), which is a calcium silicate cement (CSC) used in dentistry, was first developed by Torabinejad et al [2]. MTA is used primarily for root canal filling, perforation repair, and retrofilling because MTA has unique biocompatibility [3], antibacterial properties [4], and sealability [5] and promotes hard tissue formation [6]. It is difficult to use because of its granular consistency, slow setting time, and initial looseness [7]

Objectives

Methods

Conclusion