Analysis of Biological Tissues and Structures: consittutive formulation and numerical modelling

Session Outline

The aim of the session is to offer reference examples pertaining to the investigation of biological tissue and structures by means of an integrated experimental and numerical approach. Constitutive formulations and parameters identification are provided for material and geometric non linear problems, reporting on computational biomechanics approach developed.

 

Lecture 1: Mechanics of urethral tissues and structures

 

The lecture refers to a general project on the mechanics in urology, with specific reference to bladder, urethra and overall functional response of the lower urinary system. In particular, the mechanics of urethral duct is treated, in consideration of the adoption of artificial sphincteric devices to overcome incontinence problems. Experimental activity is performed on urethral tissues and structural test are carried out on the overall urethral duct, to provide constitutive parameters definition within the formulated material model. The numerical analysis of urethral duct leads to a valid set of results pertaining to the definition of the mechanics of urethral lumen occlusion under the action of prosthetic device, stressing the integration with surgical practice.

Histological section of urethral duct (a), solid model (b), numerical model (c). Urethral lumen occlusion: subsequent steps during the action of a pressure action induced by sphincteric device (d).
Histological section of urethral duct (a), solid model (b), numerical model (c). Urethral lumen occlusion: subsequent steps during the action of a pressure action induced by sphincteric device (d).

Lecture 2: Dental implant biomechanics

 

The lecture pertains to the analysis of the biomechanical behaviour of prosthetic devices with specific regard to dental implants, considering the interaction phenomena occurring with trabecular and cortical bone in the upper and lower jaw, considering the different prosthetic configurations and in direct relation with clinical practice.

 

Notes on bone constitutive formulation are reported. The solid model of the anatomical region and of the specific implants and overall dental framework are described, together with specific numerical models. The biomechanical analysis mimics the specific surgical practice.

 

Overall view of implant and abutment inserted in the lower jaw region (a). Finite element analysis of implant-abutment interaction (b,c). Finite element analysis of press fit condition (d) and misfit condition of a two-implant frame (e)
Overall view of implant and abutment inserted in the lower jaw region (a). Finite element analysis of implant-abutment interaction (b,c). Finite element analysis of press fit condition (d) and misfit condition of a two-implant frame (e)

Lecture 3: Constitutive formulation and numerical modelling for investigation of foot mechanics

 

The lecture pertains to the analysis of biomechanical behaviour of foot tissue and structure, with regard to bone, cartilages, ligaments, tendons, adipose tissue and skin. In particular, the adipose tissue are treated, pointing out the formulations developed and the structural analysis performed with specific regard to rear foot. Notes are also reported to offer a general overview of the investigation performed on foot mechanics, considering the different components and evaluating the effects of damage phenomena occurring because of ageing, pathologies and traumas.

 

Finite element model of the foot, pointing out adipose tissue region (a). Finite element analysis of ankle joint (b) in plantarflexion and dorsiflexion conditions. Response of cartilage in damaged condition because of arthritic degradation (c).
Finite element model of the foot, pointing out adipose tissue region (a). Finite element analysis of ankle joint (b) in plantarflexion and dorsiflexion conditions. Response of cartilage in damaged condition because of arthritic degradation (c).