Calcium phosphate precipitation in experimental gaps between fluoride-containing fast-setting calcium silicate cement...

Area of Science:

• Biomaterials Science
• Dental Materials Research
• Nanotechnology in Dentistry

Background:

• Dental restorations require durable cement interfaces to prevent microleakage.
• Traditional cements may exhibit limited gap-sealing capabilities, impacting long-term restoration success.
• Novel fast-setting calcium silicate cement (novel-CSC) with fluoride has been developed for tooth crown applications.

Purpose of the Study:

• To evaluate the efficacy of a novel fluoride-containing calcium silicate cement (novel-CSC) in closing experimental gaps at the dentin-cement interface.
• To compare the gap-closing ability of novel-CSC with established dental materials like Vitrebond and GC Fuji II LC.
• To assess the morphology, chemical composition, and long-term integrity of precipitates formed by novel-CSC.

Main Methods:

• Creation of experimental gaps (50 and 300 μm) between dentin and tested cements.
• Immersion of specimens in phosphate-buffered saline for up to 96 hours to measure gap closure.
• Analysis using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX) for precipitate characterization.
• High-resolution micro-computed tomography (μCT) to assess precipitate integrity and continuity over 180 days.

Main Results:

• Novel-CSC completely closed experimental gaps within 96 hours, irrespective of initial gap width.
• SEM/EDX analysis confirmed precipitates were primarily calcium and phosphorus-based, forming globular structures.
• μCT revealed continuous calcium phosphate precipitation, including apatite, in novel-CSC samples.
• Resin-modified glass ionomers showed no precipitate formation in the experimental gaps after 180 days.

Conclusions:

• Novel-CSC demonstrates superior performance in closing dentin-cement gaps through continuous calcium phosphate precipitation.
• The formed precipitates, rich in calcium and phosphorus, contribute to the long-term integrity and sealing of the interface.
• Novel-CSC shows significant potential as an advanced dental cement for restorative applications, offering enhanced sealing properties compared to conventional materials.