Porous Elastomer Implant Surface Reduces Fibrous Capsule Formation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Implantable medical devices often induce a foreign body response leading to fibrous capsule formation and capsular contracture, which can cause aesthetic and painful issues, and current textured surface approaches do not fully prevent these complications.

Innovation Solution

A biocompatible implantable device featuring a porous material with an elastomer matrix and interconnected pores, providing high porosity and elastic elongation to promote tissue growth and reduce fibrous capsule formation, while maintaining mechanical strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a smooth surface is used on implantable medical devices, then manufacturing is simple, but fibrous capsule formation and capsular contracture occur

Engineering Contradiction:
Improvesurface fabrication simplicityVSAvoidfibrous capsule formation
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The patent applies porous materials with controlled pore sizes (5-50 micrometers) and high porosity (80-90%) to the implantable device surface. This porous structure promotes cellular ingrowth and tissue integration, effectively preventing fibrous capsule formation and capsular contracture while maintaining manufacturing feasibility through techniques like phase separation and foam replication

Inventive Principle:
Principle #31Porous materials

Solution Approach 2:

The patent uses composite materials combining elastomer matrices with porous structures and various additives (plasticizers, crosslinking agents, bioactive molecules). These composite materials provide both the mechanical properties needed for implantability and the biological functionality to prevent capsular contracture, resolving the contradiction between simple manufacturing and harmful fibrous capsule formation

Inventive Principle:
Principle #40Composite materials

2Object-affected harmful factors

If the surface is textured with hills and valleys, then capsular formation is reduced, but capsular contracture can still occur and manufacturing complexity increases

Engineering Contradiction:
Improvecapsular formation reductionVSAvoidsurface architecture complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent transitions from simple hill-and-valley texturing to a sophisticated porous structure with interconnected pores of controlled size (5-50 micrometers). This porous architecture more effectively prevents both capsular formation and contracture by promoting cellular ingrowth throughout the surface, while the manufacturing processes (phase separation, foam replication) keep complexity manageable

Inventive Principle:
Principle #31Porous materials

Solution Approach 2:

The patent applies different pore sizes, distributions, and densities in different regions of the implant surface to optimize local biological responses. This local quality approach enhances prevention of capsular contracture in critical areas while maintaining overall structural integrity and manageable manufacturing complexity

Inventive Principle:
Principle #3Local quality

3Object-affected harmful factors

If porosity is increased to promote cellular ingrowth, then fibrous capsule formation is reduced, but mechanical strength may be compromised

Engineering Contradiction:
Improvefibrous capsule preventionVSAvoidmaterial mechanical strength
Core Design Contradiction:
Object-affected harmful factorsVSStrength

Solution Approach 1:

The patent employs composite elastomer materials with crosslinked networks and reinforcement phases that maintain high mechanical strength even at 80-90% porosity. The composite structure includes elastomer matrices with controlled crosslinking densities and potential reinforcement from nanomaterials or fiber networks, allowing high porosity for cellular ingrowth while preserving the mechanical strength needed for implantable devices

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent optimizes multiple parameters simultaneously: pore size (5-50 micrometers), porosity (80-90%), elastomer composition, crosslinking density, and pore wall thickness. By carefully controlling these parameters, the material achieves both high cellular ingrowth capability and sufficient mechanical strength for implantable applications, resolving the contradiction between fibrous capsule prevention and mechanical strength

Inventive Principle:
Principle #35Parameter changes

4Adaptability or versatility

If elastic elongation is increased to at least 80%, then tissue integration is improved, but material structural stability may be reduced

Engineering Contradiction:
Improvetissue integration capabilityVSAvoidmaterial structural stability
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The patent uses composite elastomer structures with crosslinked networks that provide both high elastic elongation (≥80%) and structural stability. The composite architecture includes flexible polymer chains for elasticity combined with crosslinking points and potential rigid reinforcement phases that maintain structural integrity during large deformations, enabling both superior tissue integration and material stability

Inventive Principle:
Principle #40Composite materials

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 porous material effectively reduces or prevents fibrous capsule formation and capsular contracture, enhancing the integration of implantable devices and minimizing scarring, while maintaining mechanical integrity and durability.

Implementation Method 1

coating the elastomer base with porogens to form an elastomer coated porogen mixture; treating the elastomer coated porogen mixture to form a porogen scaffold comprising fused porogens

Methodology Applied
Scientific EffectPhase separation:

Implementation Method 2

The porous material has a porosity of 80-90% and exhibits an elastic elongation of at least 80%

Methodology Applied
Scientific EffectPorosity: Porosity

Implementation Method 3

the material exhibits an elastic elongation of at least 80%

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 4

The porous materials promote cellular ingrowth in and around an implantable medical device and reduce or prevent a foreign body response

Methodology Applied
Scientific EffectCellular ingrowth:

Data Source

PatentEP2571543B1Porous materials, methods of making and uses
Publication Date: 2018.12.05 ALLERGAN INC
  • EP2571543B1 patent drawingFigure 1A~1B
  • EP2571543B1 patent drawingFigure 2A~2D
  • EP2571543B1 patent drawingFigure 3A~3D

AI summary

The present specification discloses porous materials, methods of forming such porous materials, biocompatible implantable devices comprising such porous materials, and methods of making such biocompatible implantable devices.