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A Simple Pit Assay Protocol to Visualize and Quantify Osteoclastic Resorption In Vitro
Published on: June 16, 2022
Mineral trioxide aggregate inhibits osteoclastic bone resorption.
D Hashiguchi1, H Fukushima, H Yasuda
1Division of Molecular Signaling and Biochemistry, Department of Biosciences, Center for Oral Biological Research, Kyushu Dental College, Fukuoka, Japan.
Journal of Dental Research
|May 3, 2011
Summary
Mineral trioxide aggregate (MTA) inhibits osteoclastic bone resorption and osteoclast formation. MTA also stimulates osteoblast differentiation, making it a useful retrofilling material in endodontics.
Area of Science:
- Biomaterials Science
- Endodontics
- Bone Biology
Background:
- Mineral trioxide aggregate (MTA) is a widely used endodontic repair material.
- While MTA's effect on osteoblast differentiation is known, its impact on osteoclastic bone resorption is less understood.
Purpose of the Study:
- To investigate the effect of MTA solution on osteoclastic bone-resorbing activity.
- To explore the mechanisms by which MTA influences osteoclast function.
Main Methods:
- Osteoclasts were formed in co-cultures of primary osteoblasts and bone marrow cells.
- MTA solution was applied, and effects on pit formation, osteoclast number, actin ring formation, c-Src activity, and gene expression (cathepsin K, mmp-9, Bim) were analyzed.
Main Results:
- MTA solution reduced osteoclastic pit formation in a dose-dependent manner.
- A 20% MTA solution inhibited bone resorption by affecting osteoclast activity, not number, and disrupted actin ring formation via c-Src signaling.
- A 50% MTA solution induced osteoclast apoptosis by increasing Bim expression.
Conclusions:
- MTA inhibits osteoclastic bone resorption through multiple mechanisms, including reducing resorbing activity and inducing apoptosis.
- MTA's dual action of stimulating osteoblast differentiation and inhibiting bone resorption supports its clinical use as a retrofilling material.
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