In cardiology and research involving the interactions between restorative materials and dental hard tissues, it is important for small changes in tooth mineral content to be measurable. Currently, transverse microradiography (TMR) is the most accepted tool for the above purpose. Electron Probe Microanalysis (EPMA) can yield both qualitative identification of elements and quantitative compositional information. The purpose of this study was to compare the mineral distribution in well-defined artificial lesions, in dentin and enamel, by the use of both TMR and EPMA on the same sample. The good correlation between the two sets of data validates EPMA as a technique and helps in the interpretation of its results. The data from TMR analysis are expressed as vol% of mineral, while EPMA gives the levels of Ca and phosphate in wt%. The conversion between the two sets of data is complicated by the fact that local density is, as yet, unknown.

T here are increasing numbers of promising technologies aimed at enhancing tooth remineralization or preventing tooth decay, yet relatively few technologies are brought to market with substantiated claims of anti-caries performance, even when favorable clinical performance has been established. Clinical trials are often viewed as the biggest challenge encountered during the development of new agents; however, there are additional and substantial challenges encountered during product development and market introduction. The aim of this paper is to provide some insight into the various challenges that might be encountered during the development of new anti-caries technologies. Such challenges may exist in formulation development, performance relative to clinically proven technologies, statistical analysis of data, and regulatory requirements.

With more than 50 years of clinical success, fluoride serves as the gold standard agent for preventing tooth decay. In particular, the action of fluoride facilitates saliva-driven remineralization of demineralized enamel and alters solubility beneficially. Still, tooth decay remains problematic, and one way to address it may be through the development of new mineralizing agents. Laboratory and clinical studies have demonstrated that the combination of fluoride and functionalized β-tricalcium phosphate ( fTCP) produces stronger, more acid-resistant mineral relative to fluoride, native β-TCP, or fTCP alone. In contrast to other calcium-based approaches that seem to rely on high levels of calcium and phosphate to drive remineralization, fTCP is a low-dose system designed to fit within existing topical fluoride preparations. The functionalization of β-TCP with organic and/or inorganic molecules provides a barrier that prevents premature fluoride-calcium interactions and aids in mineralization when applied via common preparations and procedures. While additional clinical studies are warranted, supplementing with fTCP to enhance fluoride-based nucleation activity, with subsequent remineralization driven by dietary and salivary calcium and phosphate, appears to be a promising approach.

The purpose of this investigator-blinded, five-treatment, crossover human intraoral study was to evaluate the effects of two experimental dentifrice formulations containing either stannous fluoride (SnF₂) or sodium fluoride (NaF) packaged with sodium hexametaphosphate in a dual-phase delivery system on demineralization-remineralization using an in situ model system. The experimental dentifrice formulations’ ability to alter demineralization-remineralization was compared to a series of three controls: SnF₂-positive control, NaF-positive control and no-fluoride placebo-negative control. The single-section crown model, developed at the University of Iowa, was used to assess the fluoride efficacy of two experimental products versus the placebo containing no fluoride and positive controls. The results of the current in situ study suggest a clinical level of anticaries activity for the experimental SnF₂ and NaF dentifrice formulations that was as good as either of the positive controls, when evaluated using polarized light microscopy. This supports the conclusion that the use of the sodium hexametaphosphate ingredient does not interfere with the normal fluoride activity of these toothpastes. In addition, the experimental SnF₂ product was numerically better than both the NaF and placebo controls at preventing demineralization of sound root surfaces.

Summary Several laboratory studies have been conducted to confirm and compare the anticaries potential of the major fluoride toothpastes currently marketed in China. This paper reports on one series of tests that was conducted under the guidance of the China National Committee for Oral Health (NCOH). In this series of tests, one of the marketed toothpastes, which is formulated with sodium fluoride (NaF) in a silica abrasive that is highly compatible with the fluoride active ingredient, provided significantly greater efficacy than all of the other toothpastes tested. This product is Crest toothpaste. On the basis of a separate series of studies conducted independently by the NCOH, Crest toothpaste received the official endorsement of the China NCOH as a proven anticaries toothpaste. The studies reported here provide additional, quantitative verification of the efficacy of this formulation. Included in this assessment of anticaries efficacy were measurements of fluoride uptake into demineralised human enamel, changes in the surface microhardness of the enamel as a function of each product tested, post resistance of remineralised enamel that was subjected to a secondary acid challenge, and quantitative microradiographic analyses of remineralised specimens. Each parameter demonstrates Crest toothpaste provides a higher level of anticaries efficacy than other fluoride toothpastes marketed in China. The results of these tests are consistent with previous tests conducted by the NCOH. Comparatif d'efficacité contre les caries du dentifrice Crest et de quelques dentifrices commercialisés en Chine ‐ résultats d'un test de mise en cycle du pH in vitro Résumé Plusieurs études ont été menées en laboratoire afin de confirmer et de comparer le potentiel cariostatique des principaux dentifrices fluorés, actuellement vendus en Chine. Cet article relate l'une des séries de tests effectués sous le contrôle du Comité National Chinois pour la Santé Bucco‐Dentaire (NCOH). Dans ce groupe de tests, l'un des dentifrices commercialisés, à base de fluor de sodium (NaF) intégré dans un abrasif au silice hautement compatible avec le fluor actif, s'est révélé nettement plus efficace que tous les autres dentifrices testés. Il s'agit du dentifrice Crest. A partir d'une série particulière de tests assurés indèpendamment par le NCOH, le dentifrice Crest a étè officiellement reconnu par le NCOH comme étant un dentifrice capable de combattre les caries. Les études dont il est question dans cet article apportent des preuves quantitatives supplèmentaires sur l'efficacité de cette formule. Parallèlement à cette évaluation de l'action cariostatique, on a mesuré la dose de fluor absorbée par l'émail humain déminéralisé, les changements dans la microdureté de surface de l'émail pour chaque produit testé, la post résistance de l'émail reminéralisé en le soumettant à une attaque acide secondaire. On a également procédé à des analyses quantitatives par microradiographie des spécimens reminéralisés. Chaque paramètre prouve que le dentifrice Crest est beaucou...