Diffusion of Ca(OH)2 associated with different vehicles: chromatographic study (high-performance liquid...

Area of Science:

• Endodontics
• Materials Science
• Biomaterials

Background:

• Root canal sealers are crucial for endodontic treatment success.
• Understanding the potential for sealer components to leach out is important for assessing biocompatibility and long-term outcomes.
• Dentin's role as a barrier to the diffusion of sealer components requires further investigation.

Purpose of the Study:

• To evaluate the diffusion of various components from root canal filling pastes through human dentine.
• To identify substances, beyond calcium (Ca2+) and hydroxyl (OH-) ions, that can permeate dentine.
• To compare the diffusion characteristics of different sealer formulations.

Main Methods:

• High-performance liquid chromatography (HPLC) was used to analyze liquid samples.
• 25 human premolar teeth were used, with canals filled with Ca(OH)2-based pastes and different vehicles.
• Samples were immersed in ultra-pure deionized water for 1678 hours to assess diffusion.

Main Results:

• Multiple substances (at least 15 in one group) other than Ca2+ and OH- were detected in the aqueous medium.
• Diffusion was observed even when the tooth acted as a barrier, although at lower levels than without a barrier.
• Group 4 (glycerin and tricresol formol) showed the highest number of detected diffused substances.

Conclusions:

• Dentine is permeable to various components of root canal filling pastes, not solely Ca2+ and OH- ions.
• The composition of the vehicle significantly influences the diffusion of sealer components through dentine.
• Further research is needed to understand the clinical implications of these diffused substances.