Fluoride uptake by enamel and dentin from bonding agents and composite resins: a comparative study

Area of Science:

• Dental Materials Science
• Biomaterials Research
• Cariology

Background:

• Fluoride-releasing dental materials aim to enhance remineralization and prevent secondary caries.
• Understanding fluoride ion diffusion and uptake in tooth structures is crucial for material efficacy.
• Previous research has explored fluoride release from various restorative agents, but comparative uptake in enamel and dentin requires further investigation.

Purpose of the Study:

• To compare in vitro fluoride uptake by enamel and dentin.
• To evaluate fluoride uptake from different combinations of fluoridated and non-fluoridated bonding agents and composite resins.
• To determine the optimal combination for maximizing fluoride ion incorporation into tooth structure.

Main Methods:

• Sixty extracted premolars were divided into three experimental groups (n=20 each).
• Teeth were restored with either fluoridated or non-fluoridated bonding agents and composite resins in specific combinations.
• Fluoride content was quantified using specific ion-electrode analysis of successive acid etch biopsies after three months of immersion in de-ionised water.

Main Results:

• Significant in vitro fluoride uptake was observed in all tested groups.
• Dentin demonstrated significantly higher fluoride uptake compared to enamel across all groups (P<0.001).
• The combination of a fluoridated bonding agent with a fluoridated composite resin (Group III) resulted in the greatest fluoride uptake in both enamel and dentin.

Conclusions:

• The combination of fluoridated bonding agents and fluoridated composite resins is highly effective in increasing fluoride uptake in dental hard tissues.
• Dentin exhibits a greater capacity for fluoride ion absorption compared to enamel from restorative materials.
• Optimizing the fluoride content of both bonding agents and composite resins maximizes therapeutic benefits against demineralization.