Nanoleakage and microshear bond strength in deproteinized human dentin

Area of Science:

• Biomaterials Science
• Dental Materials
• Adhesive Dentistry

Background:

• Dentin bonding systems (DBS) are crucial for dental restorations.
• Dentin surface treatment influences the bond strength and durability of DBS.
• Sodium hypochlorite (NaOCl) is used for dentin deproteinization, potentially affecting interfacial integrity.

Purpose of the Study:

• To evaluate the effect of dentin deproteinization with NaOCl on microshear bond strength (microSBS) and nanoleakage.
• To compare the performance of three different dentin bonding systems (SBMP, PB, SE) after NaOCl treatment.

Main Methods:

• Occlusal dentin surfaces were treated with phosphoric acid or phosphoric acid followed by NaOCl.
• Three DBS (Scotchbond Multipurpose, Prime & Bond NT, Clearfil SE Bond) were applied.
• Microshear bond strength was tested after 1 week of water storage.
• Nanoleakage was assessed using scanning electron microscopy (SEM).

Main Results:

• NaOCl treatment increased microSBS for Prime & Bond NT but reduced it for Clearfil SE Bond.
• Scotchbond Multipurpose showed no significant change in microSBS with NaOCl treatment.
• Nanoleakage patterns varied among DBS; Clearfil SE Bond showed no nanoleakage, while Scotchbond Multipurpose exhibited nanoleakage regardless of treatment.

Conclusions:

• The influence of dentin deproteinization with NaOCl on DBS performance is formulation-dependent.
• NaOCl treatment can enhance or compromise bond strength and nanoleakage depending on the specific DBS used.
• Careful selection of DBS is necessary when considering dentin deproteinization protocols.