When pulp tissue exposure occurs, it is fundamental to protect and seal the pulpal tissue from noxious agents to prevent irreversible pulpitis or necrosis. Dental trauma, deep caries or iatrogenic proceedings are considered the main reasons for pulp exposure. When the pulpal tissue is involved, in absence of bleeding and signs of inflammation, direct pulp capping is commonly recommended.
This clinical procedure mainly consists in the application of a biocompatible material at the level of the exposed pulp to seal the communication between the pulp chamber and the dentinal substrate. The thin barrier of biomaterial has a twofold intent: to protects the pulp complex and, consequently, to preserve the tooth vitality through a natural mechanism of potential tissue repair, that leads to the formation of reparative dentin. In literature, it has been widely documented that dental pulp could form a hard tissue barrier (dentin bridge) after direct capping of pulp thanks to the induction of differentiation of odontoblast-like cells from dental pulp that produce tertiary dentin in the exposed area.
In order to obtain a successful outcome after pulp capping, the characteristics of the material employed, such as the biocompatibility, the antibacterial properties, the sealing capability and the ability to induce tissue healing, are of absolute importance.
A recent review published by Anabela B. Paula et al. compared the effectiveness of different direct pulp biomaterials. Mineral trioxide aggregate (MTA) cement, calcium hydroxide cement, tricalcium silicate cement, and adhesive systems were considered and evaluated in terms of success rate, inflammatory response, and dentin bridge formation. The authors identified 819 studies but only 46 articles were included in the systematic review. The results of the study showed a better clinical performance of MTA cement compared to calcium hydroxide cement. However, no differences were detected when MTA was compared to tricalcium silicate.
MTA proved to be a good bioactive, biocompatible and anti-bacterial material, with the ability to maintain the seal over time. However, the long setting time, the poor handling, the high cost, and the potential to decolorate the tooth are some of the clinical disadvantages compared to other materials.
The work of Anabela B. Paula concluded that even if tricalcium silicate performed better in terms of inflammatory response and quality of dentin bridge, MTA showed the higher success rate. The employment of dental adhesives as pulp barriers were discouraged because of the reduced number of clinical successful results over time.
For additional informations:
Direct Pulp Capping: What is the Most Effective Therapy?—Systematic Review and Meta-Analysis
Editorials 06 March 2019