Cellular Intraoral Appliance Stiffness for Nonlinear Tooth Forces

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional intraoral appliances with homogeneous materials lack the ability to generate sufficient force and control over tooth repositioning, often resulting in inadequate mechanical properties and discomfort for patients, as they typically provide linear force profiles with limited strain windows.

Innovation Solution

The development of intraoral appliances with adaptive cellular materials and structures that utilize interconnected unit cells with varying elongation characteristics, allowing for customized mechanical properties and non-linear force/strain profiles, enabling more effective tooth repositioning with reduced patient discomfort.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If conventional homogeneous materials are used in intraoral appliances, then the appliance structure is simple and easy to manufacture, but the mechanical properties are insufficient and cannot provide sufficient force control for tooth repositioning

Engineering Contradiction:
Improveforce generation capabilityVSAvoidappliance structure
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent applies local quality by creating regions with different cellular densities within the appliance. High-density cellular regions provide greater force where needed for tooth movement, while low-density regions provide flexibility and comfort. This spatial variation in material properties allows the appliance to generate sufficient force control without requiring a completely complex overall structure.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent uses composite materials by combining solid polymeric material with cellular structures of varying densities. This creates a composite structure that integrates both rigid force-generating regions and flexible comfort regions, enabling the appliance to simultaneously provide sufficient force for tooth repositioning and maintain structural simplicity.

Inventive Principle:
Principle #40Composite materials

2Duration of action of moving object

If conventional linear force profile materials are used, then the material provides consistent force, but the strain window is limited and elongation rate is insufficient

Engineering Contradiction:
Improvestrain windowVSAvoidpatient comfort
Core Design Contradiction:
Duration of action of moving objectVSEase of operation

Solution Approach 1:

The patent applies local quality by creating regions with different cellular densities within the appliance. High-density cellular regions provide greater force where needed for tooth movement, while low-density regions provide flexibility and comfort. This spatial variation in material properties allows the appliance to generate sufficient force control without requiring a completely complex overall structure.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent changes material parameters by varying the cellular density throughout the appliance structure. This creates a gradient of mechanical properties where stiffer regions provide force and more compliant regions extend the strain window and improve comfort. The parameter changes enable the appliance to maintain force generation over a larger strain range.

Inventive Principle:
Principle #35Parameter changes

3Manufacturing precision

If cellular materials with small unit cells are used to achieve controlled mechanical properties, then the mechanical control is enhanced, but the fabrication difficulty and cost increase

Engineering Contradiction:
Improvemechanical property controlVSAvoidfabrication process
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent applies segmentation by dividing the appliance into regions with different cellular densities rather than using uniformly small unit cells throughout. This allows mechanical property control to be achieved through regional variation in cell size and density, which is more easily manufactured than uniformly fine cellular structures while still providing the desired mechanical control.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent changes material parameters by varying the cellular density throughout the appliance structure. This creates a gradient of mechanical properties where stiffer regions provide force and more compliant regions extend the strain window and improve comfort. The parameter changes enable the appliance to maintain force generation over a larger strain range.

Inventive Principle:
Principle #35Parameter changes

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

These appliances provide enhanced mechanical properties, such as higher Young's modulus and elongation rates, allowing for more precise control over force application, increased customization, longer appliance lifetimes, and reduced discomfort for patients.

Implementation Method 1

cellular materials have received increased attention for their enhanced and controllable mechanical properties

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3687439B1Cellular architecture for controlled focal stiffness across intraoral appliances
Publication Date: 2024.05.15 ALIGN TECHNOLOGY INC
  • EP3687439B1 patent drawingFigure 1
  • EP3687439B1 patent drawingFigure 2(A)~2(C)
  • EP3687439B1 patent drawingFigure 3(A)~3(C)

AI summary

Described herein are intraoral appliances with adaptive cellular materials and structures to provide enhanced mechanical properties and orthodontic functionality, and related methods. The described appliances may have higher Young's modulus and elongation rate than appliances made from conventional materials. Further, the described appliances may have desirable non-linear force/strain profiles. Additionally, the control provided by using cellular structures allow for increased customization for individual patients. Thus, the described appliances may be more effective, have longer appliance lifetimes and/or provide less discomfort to patients.