Evaluation of Bond Strength Between Premixed and Powder-Liquid Mineral Trioxide Aggregate and Various Glass Ionomer Cements: An In Vitro Study

Summary

Here, we present an in vitro study evaluating the short-term bond strength between two formulations of mineral trioxide aggregate (powder-liquid and premixed) and two types of glass ionomer cements (conventional and resin-modified).

Abstract

This study aims to comparatively evaluate the bond strengths of premixed and powder-liquid forms of mineral trioxide aggregate (MTA) to conventional glass ionomer cement (CGIC) and resin-modified glass ionomer cement (RMGIC).

Sixty test specimens were prepared and divided into four groups (n = 15) based on the combinations of MTA type and glass ionomer cement used. Following MTA placement and a standardized 15 min setting period, the glass ionomer materials were applied according to the manufacturers' instructions. Shear bond strength testing was performed using a universal testing machine, and failure modes were analyzed under a stereomicroscope.

The powder-liquid MTA combined with RMGIC exhibited the highest bond strength (p < 0.001). RMGIC showed significantly higher bond strength than CGIC for both MTA forms. A statistically significant difference in failure mode distribution was observed in the premixed MTA group (p = 0.020).

The findings demonstrate that both the physical form of MTA and the chemical composition of the ionomer cement significantly affect bond strength. Moreover, the distribution of failure modes differed across groups: cohesive failures predominated in the premixed MTA-RMGIC group, whereas mixed and adhesive failures were more common with CGIC. These results suggest that the powder-liquid MTA combined with RMGIC provides the most reliable adhesion and may be preferable in clinical scenarios requiring durable bonding.

Introduction

Vital pulp therapy (VPT) is a therapeutic intervention aimed at preserving the structural integrity of compromised pulp tissue, typically due to factors such as carious lesions or traumatic injuries. VPT has become a cornerstone of contemporary endodontics due to its ability to preserve healthy pulp tissue by supporting the body's intrinsic healing and repair mechanisms. These therapeutic interventions are predicated on the inherent cellular repair mechanisms of the pulp^1,2. Consequently, the utilization of dental materials in this setting is predicated on the promotion of hard tissue formation by residual....

Protocol

NOTE: This in vitro study did not require ethical approval as no human or animal subjects were involved. The study was conducted in accordance with the principles of the Declaration of Helsinki.

1. Sample preparation

NOTE: Sample size calculation was based on an effect size of 0.40, α = 0.05, and power = 0.80, resulting in a minimum of 10 samples per group. To enhance statistical reliability, 15 samples per group were used.

1. Use a total of 60 standardized metal rings, each with a cylindrical cavity of 4 mm in diameter and 3 mm in depth, to contain the MTA materials (see <....

Results

The distribution of the force values measured at the moment of separation of the glass ionomer cements from the MTA surface is presented in Table 1. The highest mean force was recorded in the group combining resin-modified glass ionomer cement with powder-liquid MTA, whereas the lowest mean force was observed in the group combining conventional glass ionomer cement with premixed MTA. When evaluated separately, the bond strength values for powder-liquid MTA were higher than those for premixed MTA in both .......

Discussion

The adhesion of MTA to overlying glass ionomer cement is influenced by several factors. Metallic oxides present on the MTA surface have the capacity to form strong chemical bonds with the glass ionomer matrix. Additionally, the presence of surface porosities enhances micromechanical retention by increasing the available surface area⁴. In the present study, the premixed MTA evaluated contains a formulation comprising tricalcium silicate, dicalcium silicate, tricalcium aluminate, calcium oxide, zirc.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Bio MTA +	Cerkamed, Poland	1703251	for obturation
BIO-C Repair	Angelus, Brazil	77418	for obturation
Glass Liner	WP Dental, Germany	241328	for sealing
Metal block	Moya Yap? Market,Sanliurfa,Turkey	ST00103	for sample preparation
Restore+	D-Tech, India	RC030424	for sealing
SPSS v29	IBM SPSS Corp, Armonk, New York, USA	https://www.ibm.com/products/spss-statistics	Statistical analysis
Stereomicroscope	Leica MZ 7.5, Leica Microsystems, Germany	10450159	for identify failure type
Universal Testing Machine	Shimadzu, AGS-X, Japan	C224-E057C	for shear bond strength measurement
VALO Cordless LED curing light	Ultradent, USA	5941	for light curing