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Particle size changes in unsealed mineral trioxide aggregate powder
William N Ha1, Bill Kahler1, Laurence James Walsh1
1University of Queensland School of Dentistry, Brisbane, Queensland, Australia.
Journal of Endodontics
|February 26, 2014
Summary
Mineral trioxide aggregate (MTA) powder particle size increases significantly after packaging is opened, especially with ProRoot MTA. Resealable packaging like MTA Angelus minimizes these detrimental changes, preserving material integrity.
Area of Science:
- Dental Materials Science
- Biomaterials Engineering
- Particle Science
Background:
- Mineral trioxide aggregate (MTA) is a widely used dental material.
- Clinicians sometimes use MTA powder beyond manufacturer guidelines.
- Packaging type affects MTA powder stability after opening.
Purpose of the Study:
- To assess particle size changes in MTA powder after package opening.
- To compare the stability of ProRoot MTA and MTA Angelus packaging.
- To determine the impact of storage on MTA powder properties.
Main Methods:
- Laser diffraction and scanning electron microscopy were used.
- MTA powder was analyzed fresh and after 2 years of storage.
- Particle size distribution and surface area were compared between packaging types.
Main Results:
- ProRoot MTA showed a 6-fold increase in particle size and a 50-fold increase in surface area after 2 years.
- MTA Angelus exhibited only a 2-fold increase in particle size and surface area.
- Increased particle size is linked to moisture absorption.
Conclusions:
- MTA powder reacts with atmospheric moisture, increasing particle size.
- This particle size increase can negatively impact MTA properties and shelf life.
- Single-use packaging systems are recommended to maintain MTA integrity.
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