Fluoride penetration into the hybrid layer from a dentin adhesive

Area of Science:

• Dental Materials Science
• Adhesive Dentistry
• Caries Prevention

Background:

• Microleakage remains a challenge in dental restorations, potentially leading to secondary caries.
• Fluoride-releasing dental adhesives offer a potential strategy to enhance caries resistance.
• Evaluating novel fluoride-containing dentin adhesives is crucial for improving restorative material performance.

Purpose of the Study:

• To assess the in vitro microleakage of a new fluoride-containing dentin adhesive.
• To determine fluoride release from the experimental adhesive.
• To investigate fluoride penetration into dentin following adhesive application.

Main Methods:

• Class V preparations in human molars were restored with either a new fluoride-containing adhesive (FB) or Scotchbond Multipurpose (SBMP).
• Restored teeth were aged, stained with silver nitrate, sectioned, and evaluated for microleakage.
• Scanning electron microprobe analysis (WDS/EDS) and ion-specific electrode measurements assessed fluoride presence, release, and penetration.

Main Results:

• Microleakage at enamel and dentin margins was similar between the FB and SBMP groups.
• Fluoride was detected within the hybrid layer of FB specimens, limited to areas with leakage.
• Fluoride release from the FB adhesive occurred at a decreasing rate over 112 days.

Conclusions:

• The new fluoride-containing dentin adhesive demonstrated comparable microleakage to a conventional adhesive.
• Evidence of fluoride release and limited penetration into the hybrid layer was established.
• The findings support the potential of this adhesive for localized fluoride delivery in restorations.