In vitro evaluation of dentinal hydraulic conductance and tubule sealing by a novel calcium-phosphate desensitizer.

Abstract

In the current trend of materials used for dentin hypersensitivity treatment, calcium-phosphate-containing desensitizers are expected to have advantages in oral environment. A newly formulated desensitizer containing tetracalcium phosphate and dicalcium phosphate anhydrous (CPD-100) was evaluated in comparison to oxalate containing desensitizer (SS) regarding permeability reduction (PR%) by measuring hydraulic conductance on the etched dentin discs in vitro. CPD-100 exhibited mean PR% of 91%, which significantly increased to 98% after immersion in artificial saliva (AS) for 4 weeks (p < 0.001), while SS showed a significant decrease from 99% to 93% (p < 0.01). SEM observation showed newly formed crystallites on CPD-100 treated dentin, which did not exist in SS treated dentin after AS immersion, suggesting that calcium oxalate inhibited formation of new calcium-phosphate minerals. Five-minute acid challenge did not significantly affect PR% of dentin treated by any of the desensitizers. The energy dispersive X-ray spectroscopy (EDS) analysis indicated that the formed layer of CPD-100 were minerals with similar Ca/P ratio to hydroxyapatite. In conclusion, the newly developed calcium-phosphate desensitizer has the potential to exhibit long-term stability in the oral environment, owing to its chemical properties that promote the crystal growth in salivary fluid.

• Authors: Ornnicha Thanatvarakorn, Syozi Nakashima, Alireza Sadr, Taweesak Prasansuttiporn, Masaomi Ikeda, Junji Tagami
• Journal: Journal of biomedical materials research. Part B, Applied biomaterials (J Biomed Mater Res B Appl Biomater) Vol. 101 Issue 2 Pg. 303-9 (Feb 2013) ISSN: 1552-4981 [Electronic] United States
• PMID: 23166091 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2012 Wiley Periodicals, Inc.

Chemical References

• Calcium Phosphates
• Dentin Desensitizing Agents

Topics

• Calcium Phosphates (chemistry, pharmacology)
• Crystallization
• Dentin (drug effects, pathology, physiopathology)
• Dentin Desensitizing Agents (chemistry, pharmacology)
• Dentin Permeability (drug effects, physiology)
• Dentin Sensitivity (drug therapy, pathology, physiopathology)
• Humans
• Hydrodynamics
• In Vitro Techniques
• Materials Testing
• Microscopy, Electron, Scanning
• Spectrometry, X-Ray Emission