Messi Biology states that the application of magnesium oxide (MgO) in dental filling materials has gradually attracted the attention of researchers and clinicians, especially in filling dental caries, repairing dentin defects, and root canal therapy. Magnesium oxide materials possess many excellent properties, including good biocompatibility, antibacterial capabilities, lower toxicity, and protective effects on teeth, making them considered one of the ideal dental filling materials. The following is a detailed introduction to the specific applications of magnesium oxide in dental filling materials:
1. Biocompatibility
Magnesium oxide is a non-toxic, non-irritating material with excellent biocompatibility. It is compatible with human tissues, particularly tooth and gingival (gum) tissues, without causing allergies or inflammatory reactions. This makes magnesium oxide a safe and reliable choice in dental restoration, especially for filling materials that remain in long-term contact with the oral cavity.
2. Antibacterial Properties
Magnesium oxide possesses natural antibacterial properties. This is because magnesium oxide can hydrolyze in water, releasing hydroxide ions (OH-), which inhibit bacterial growth. In the treatment of caries, using magnesium oxide filling materials can effectively reduce the occurrence of bacterial infection and inflammation, preventing the root canal or repaired area from being reinfected. This is particularly crucial for filling materials in root canal therapy, as it can reduce postoperative complications.
3. Promoting Tooth Remineralization
Magnesium oxide can react with calcium and phosphorus compounds in the oral cavity to promote tooth remineralization. Magnesium oxide can release calcium ions* and hydroxide ions; these ions help strengthen the structure and hardness of teeth, assisting the tooth in recovering parts of its mineralized layer. Therefore, magnesium oxide acts not only as a filling material but also aids in tooth repair and regeneration.
(Translator’s Note: While the source text mentions releasing calcium ions, pure MgO typically releases magnesium ions. This may refer to a composite reaction or specific material formulation).
4. Protective Effect on Teeth
The hardness and density of magnesium oxide materials allow them to effectively protect dentin during dental restoration. It provides relatively stable protection, preventing the filled area from being affected by external forces or wear. Magnesium oxide materials also have low expansibility, allowing them to better adapt to the shape of the tooth and avoid the creation of secondary caries or cracks.
5. As Root Canal Filling Material
The application of magnesium oxide in root canal therapy also demonstrates unique advantages. Traditional root canal filling materials (such as root canal pastes, zinc chloride, etc.) may possess certain toxicity and irritation, whereas the use of magnesium oxide as a root canal filling material can effectively avoid these issues. Furthermore, the use of magnesium oxide in the root canal can form a robust sealing layer, preventing bacteria from re-entering the canal and reducing the risk of infection.
6. Adjustability and Adaptability
A significant advantage of magnesium oxide in dental filling materials is its excellent adjustability. By altering the size and proportion of magnesium oxide particles, its mechanical properties, hardness, antibacterial capabilities, and bonding strength with teeth can be adjusted. Therefore, in practical applications, magnesium oxide can be optimized according to specific clinical needs to meet different dental restoration requirements.
7. Application in Aesthetic Restoration
The transparency and good color of magnesium oxide materials give them certain advantages in dental aesthetic restoration. Especially in anterior tooth restoration, magnesium oxide can provide a relatively natural appearance, avoiding the color discrepancies or unsightly finishes often caused by certain metal or resin materials.
8. Long-term Stability
Magnesium oxide exhibits good stability when used in the oral cavity over long periods. It has strong resistance to acid-base changes, temperature fluctuations, and mechanical pressure within the oral environment, meaning it does not easily degrade or sustain damage during long-term use.
9. Low Sensitivity and Low Toxicity
Compared to certain traditional filling materials containing heavy metals or other harmful components, magnesium oxide filling materials have low sensitivity and low toxicity. This means the probability of patients experiencing discomfort after using magnesium oxide fillers is lower, also reducing potential harm to the human body.
10. Degradability and Eco-friendliness
Magnesium oxide is an environmentally friendly material with good degradability. During long-term use, magnesium oxide will gradually decompose and react with ions in the surrounding environment, ultimately forming harmless products. This makes magnesium oxide a green alternative solution in dental applications, contributing to the reduction of environmental pollution.