Zinc Phosphate Oral Care Compositions for Stannous Ion Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional oral care compositions face challenges in achieving antibacterial efficacy while maintaining palatability and avoiding the drawbacks of high zinc concentrations, astringency, and instability of stannous ions, such as stannous fluoride, which are commonly used for their antimicrobial properties.
Innovation Solution
Incorporating specific amounts of zinc phosphate and stannous pyrophosphate, along with stannous fluoride, to enhance the delivery and stability of stannous ions in oral care compositions, thereby improving antimicrobial efficacy and reducing unpleasant tastes and staining.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high concentrations of zinc (e.g., 2% or more) are used to achieve antibacterial efficacy, then antimicrobial effectiveness is improved, but astringent taste and user acceptability worsen
Solution Approach 1:
The patent changes the chemical form of zinc from conventional soluble zinc salts to zinc phosphate (insoluble in water), and uses acidulation during brushing to convert it to soluble forms in situ. This parameter change allows achieving antimicrobial effectiveness while avoiding the astringent taste associated with high concentrations of conventional zinc salts.
Solution Approach 2:
The patent introduces acidulants (e.g., citric acid, ascorbic acid) as intermediaries that convert insoluble zinc phosphate to soluble zinc forms during the brushing process. This intermediary mechanism enables controlled release of zinc ions at the application site, providing antimicrobial action without the need for high concentrations of pre-dissolved zinc that cause astringency.
2Reliability
If stannous salts (e.g., stannous fluoride) are used for plaque prevention, then antimicrobial effectiveness is improved, but stability, staining, and astringency worsen
Solution Approach 1:
The patent uses stannous phosphate as an insoluble reservoir that releases stannous ions gradually during brushing. This approach replaces the need for stable pre-dissolved stannous salts with a stable insoluble form that provides controlled, short-term release of active ions during the brief brushing period, avoiding stability issues while maintaining effectiveness.
Solution Approach 2:
The patent employs acidulants as intermediaries to convert insoluble stannous phosphate to soluble stannous forms during brushing. This intermediary conversion mechanism enables stable storage of stannous ions in an insoluble form while providing effective release at the application site, resolving the stability-effectiveness contradiction.
3Reliability
If stannous salts are used for gingivitis reduction, then therapeutic benefit is improved, but precipitation and loss of therapeutic properties worsen
Solution Approach 1:
The patent uses stannous phosphate as a stable insoluble reservoir that releases stannous ions during the short duration of brushing. This approach eliminates precipitation problems associated with storing stannous ions in aqueous solution, as the ions are released in controlled amounts during use rather than being pre-dissolved and prone to precipitation over time.
Solution Approach 2:
The patent changes the solubility parameter of stannous ions by using insoluble stannous phosphate that converts to soluble forms in the acidic oral environment during brushing. This parameter change ensures stability during storage while providing effective release during use, preventing precipitation and loss of therapeutic properties.
4Stability of the object's composition
If low water oral care compositions are used to improve stannous ion stability, then stability is improved, but rheological properties and ease of formulation worsen
Solution Approach 1:
The patent uses insoluble stannous phosphate as a stable reservoir that requires no special low-water formulation techniques. The insoluble nature of stannous phosphate provides inherent stability without compromising the aqueous-based formulation, eliminating the need for complex low-water or dual-phase systems while maintaining ease of manufacture.
5Stability of the object's composition
If dual phase systems are used to improve stannous ion stability, then stability is improved, but manufacturing cost and complexity worsen
Solution Approach 1:
The patent uses a single-phase aqueous formulation containing insoluble stannous phosphate particles. This simple single-phase system eliminates the complexity of dual-phase systems while providing equivalent stability benefits, as the insoluble stannous phosphate naturally resists precipitation and degradation in the aqueous environment without requiring phase separation or special packaging.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The combination of zinc phosphate and stannous pyrophosphate enhances the delivery of stannous ions, providing effective antibacterial action against plaque and gingivitis while maintaining a pleasant taste and stability, thus improving oral health outcomes.
Implementation Method 1
Incorporating specific amounts of zinc phosphate and stannous pyrophosphate, along with stannous fluoride, to enhance the delivery and stability of stannous ions in oral care compositions
Implementation Method 2
enhance the delivery and stability of stannous ions in oral care compositions, thereby improving antimicrobial efficacy and reducing unpleasant tastes and staining
Implementation Method 3
providing effective antibacterial action against plaque and gingivitis while maintaining a pleasant taste and stability
Data Source
AI summary
This invention relates to oral care compositions comprising zinc phosphate, a first source of stannous (e.g., stannous fluoride); and a second source of stannous, wherein the second source of stannous comprises stannous pyrophosphate, as well as to methods of using and of making these compositions.