Phosphonic Acid Dental Polymers for Adhesion Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dental materials face challenges in achieving long-lasting adhesion to tooth enamel and dentin while maintaining storage stability, with existing acidic monomers offering limited adhesion and stability.
Innovation Solution
The use of radically polymerizable oligomers or polymers with strongly acidic phosphonic acid groups, combined with acid group-containing monomers and non-acidic monomers, enhances adhesion through surface etching and ionic binding, improving mechanical and adhesive properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If acidic monomers are used to improve adhesion to tooth structure, then adhesion strength is improved, but storage stability deteriorates
Solution Approach 1:
The patent changes the chemical parameter of acidity by using phosphonic acid groups (pKa1 ≈ 2.0) instead of conventional carboxylic acid groups (pKa ≈ 4.5). This parameter change enables stronger adhesion to tooth structure while the specific molecular structure of the phosphonic acid-containing polymers maintains storage stability, resolving the contradiction between adhesion strength and storage stability.
Solution Approach 2:
The patent creates composite dental materials that combine phosphonic acid-containing polymers with conventional dental monomers and fillers. This composite approach allows the phosphonic acid groups to provide superior adhesion to tooth structure while the overall composite formulation maintains storage stability and compatibility with existing dental material systems.
2Strength
If strongly acidic groups are used to etch tooth surface, then adhesion is improved, but material compatibility deteriorates
Solution Approach 1:
The patent modifies the acidity parameter by introducing phosphonic acid groups with pKa1 ≈ 2.0, which are strongly acidic yet compatible with conventional dental materials. These groups provide effective surface etching and adhesion while maintaining compatibility with radical polymerization processes and conventional dental monomers, thus resolving the contradiction between adhesion strength and material compatibility.
Solution Approach 2:
The phosphonic acid-containing polymers act as intermediary substances between the tooth structure and the conventional dental composite materials. They provide a bridge that enables strong bonding to tooth structure through phosphonic acid groups while remaining compatible with the radical polymerization system and other dental materials, thus mediating between adhesion requirements and material compatibility.
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
This approach results in significantly higher adhesion to tooth structures and storage stability, ensuring durable bonding and compatibility with conventional dental monomers.
Implementation Method 1
The strongly acidic groups can etch the surface of the hard tooth substance and thereby roughen it, which leads to a mechanically improved adhesion to the hard tooth substance
Implementation Method 2
In addition, the acid groups can ionically bind Ca2+
Implementation Method 3
The acidic polymers used according to the invention are radically polymerizable, i.e. they contain at least one radically polymerizable group. The polymerizable groups of the acidic polymers cause the polymers to be covalently bound into the polymer network during free-radical polymerization
Data Source
AI summary
Radically polymerizable dental material containing at least one radically polymerizable oligomer or polymer with strongly acidic groups, having a number-average molar mass of 1000 to 200000 g/mol.