Multilayer Orthodontic Aligner with Varying Bending Stiffness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing orthodontic aligner trays made from high modulus polymeric materials can cause discomfort due to repeated contact with oral tissues and may lose repositioning force over time, while softer rubbery elastomers are insufficient for effective tooth alignment in a reasonable time frame.
Innovation Solution
A system of orthodontic aligner trays with varying bending stiffness factors, formed from multilayered polymeric materials, is used sequentially to apply controlled forces for tooth repositioning, combining flexible and rigid materials to maintain comfort and achieve precise tooth movement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If high modulus polymeric materials are used in orthodontic aligner trays, then effective repositioning force is provided, but patient comfort deteriorates due to repeated contact with oral tissues
Solution Approach 1:
The aligner tray is segmented into multiple layers with different polymeric materials, each layer contributing different mechanical properties. The multilayer construction allows the composite structure to provide effective repositioning force while the softer outer layers maintain patient comfort during repeated contact with oral tissues.
Solution Approach 2:
The patent employs composite materials by combining multiple polymeric layers with different modulus values within a single aligner tray. This composite construction integrates the high modulus material's force delivery capability with the low modulus material's comfort characteristics, resolving the contradiction between effective tooth movement and patient comfort.
2Stability of the object's composition
If high modulus polymeric materials are used in orthodontic aligner trays, then stable force delivery is achieved, but stress retention behavior deteriorates over time
Solution Approach 1:
The aligner tray is segmented into multiple layers with different polymeric materials, each layer contributing different mechanical properties. The multilayer construction allows the composite structure to provide effective repositioning force while the softer outer layers maintain patient comfort during repeated contact with oral tissues.
Solution Approach 2:
The patent employs composite materials by combining multiple polymeric layers with different modulus values within a single aligner tray. This composite construction integrates the high modulus material's force delivery capability with the low modulus material's comfort characteristics, resolving the contradiction between effective tooth movement and patient comfort.
3Reliability
If rubbery elastomer materials are used in orthodontic aligner trays, then stress retention behavior is excellent, but tooth movement effectiveness deteriorates due to insufficient stiffness
Solution Approach 1:
The aligner tray is segmented into multiple layers with different polymeric materials, each layer contributing different mechanical properties. The multilayer construction allows the composite structure to provide effective repositioning force while the softer outer layers maintain patient comfort during repeated contact with oral tissues.
Solution Approach 2:
The patent employs composite materials by combining multiple polymeric layers with different modulus values within a single aligner tray. This composite construction integrates the high modulus material's force delivery capability with the low modulus material's comfort characteristics, resolving the contradiction between effective tooth movement and patient comfort.
4Ease of manufacture
If a single polymeric material is used in orthodontic aligner trays, then manufacturing is simplified, but performance adaptability deteriorates across different treatment stages
Solution Approach 1:
The aligner tray is segmented into multiple layers with different polymeric materials, each layer contributing different mechanical properties. The multilayer construction allows the composite structure to provide effective repositioning force while the softer outer layers maintain patient comfort during repeated contact with oral tissues.
Solution Approach 2:
The multilayer polymeric construction provides multi-functionality within a single aligner tray, combining force delivery, comfort, and stress retention functions in one device. This universal design eliminates the need for multiple different tray types while maintaining adaptability across treatment stages.
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 system effectively accelerates tooth movement in early stages while maintaining control and comfort, reducing refinement steps and ensuring predictable treatment outcomes by adjusting stiffness throughout the treatment process.
Implementation Method 1
The polymeric materials making up the shell are selected to exert force on one or more teeth to resiliently and incrementally reposition selected teeth
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A system for repositioning teeth a patient from an initial tooth arrangement to a final tooth arrangement includes a plurality of incremental position adjustment appliances, each having an arrangement of cavities shaped to receive and reposition teeth of the patient. The cavities in at least one appliance in the system have a different geometry than that of at least one other appliance in the system. At least some of the appliances in the system are successively worn by the patient to exert force on at least one tooth and move the teeth of the patient from a first arrangement to a successive arrangement different from the first arrangement. The system includes a first multilayer shell with a bending stiffness factor less than about 0.1 GPa*mm3 and an elastic modulus no greater than about 1.5 GPa; and a second shell with a bending stiffness factor greater than 0.1 GPa*mm3.