Characterization of auxetic polyurethanes foam for biomedical implants

AbstractAging, accidents and diseases are the leading causes of disability in today’s world. Therefore, implants and prostheses for hard and soft tissues are becoming increasingly common to restore daily activity and improve the quality of life of patients. Although implants have been extensively developed and are in the clinical use, deformation mechanism, inflexibility and mismatch of the elastic and mechanical behavior of the implants with native tissues are challenges for tissue engineering. The objective of this study was to characterize auxetic polyurethane foam as an auxetic soft tissue implant based on mathematical modeling using a nonlinear elasticity theory. The compressibility effects on auxetic soft tissue implants due to equibiaxial loading were studied. Numerical results were computed using experimentally obtained data and compared with the non-auxetic behavior of a soft tissue.

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Bone Pain in Multiple Myeloma (BPMM)—A Protocol for a Prospective, Longitudinal, Observational Study

Cancers ◽

10.3390/cancers13071596 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1596

Author(s):

Marta Diaz-delCastillo ◽

Rebecca E. Andrews ◽

Aritri Mandal ◽

Thomas L. Andersen ◽

Andrew D. Chantry ◽

...

Keyword(s):

Quality Of Life ◽

Multiple Myeloma ◽

Observational Study ◽

Bone Turnover ◽

Bone Pain ◽

Subjective Experience ◽

Prospective Longitudinal ◽

Bone Turnover Biomarkers

Multiple myeloma (MM) is a bone marrow neoplasia that causes bone pain in 70% patients. While preclinical models of MM have suggested that both nerve sprouting and nerve injury may be causative for the pain, there is a lack of clinical data. Thus, the primary aims of this clinical study are: (1) to provide a deep characterization of the subjective experience of pain and quality of life in MM patients; (2) to investigate disturbances in the bone innervation of MM patients. Secondary aims include exploring correlations between pain and serum inflammatory and bone turnover biomarkers. In a prospective, observational study (clinicaltrials.gov: NCT04273425), patients with suspected MM requiring a diagnostic iliac crest biopsy at Sheffield Teaching Hospital (UK) are invited to participate. Consenting patients answer seven standardized questionnaires assessing pain, quality of life and catastrophizing. Bone turnover biomarkers and inflammatory cytokines are measured in fasting serum samples, and bone innervation is evaluated in diagnostic biopsies. MM patients are invited to a follow-up upon completion of first line treatment. This will be the first deep characterization of pain in MM patients and its correlation with disturbances in bone innervation. Understanding how bone turnover and inflammation correlate to pain in MM is crucial to identify novel analgesic targets for this condition.

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Health‐related quality of life in necrotising soft tissue infection survivors: perspective from an Australian tertiary referral centre

ANZ Journal of Surgery ◽

10.1111/ans.16540 ◽

2021 ◽

Author(s):

Patrick Lu ◽

Margaret Angliss ◽

Eldho Paul ◽

Frank Bruscino‐Raiola

Keyword(s):

Quality Of Life ◽

Soft Tissue ◽

Soft Tissue Infection ◽

Health Related Quality ◽

Referral Centre ◽

Tertiary Referral ◽

Tertiary Referral Centre ◽

Related Quality ◽

Health Related

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Central perforated VRAM flap and neurostimulated levator augmentation for functional and aesthetical reconstruction after abdominoperineal excision in cancer

Technology and Health Care ◽

10.3233/thc-213021 ◽

2021 ◽

pp. 1-11

Author(s):

Silvia Bernuth ◽

Michael Jakubietz ◽

Christoph Isbert ◽

Joachim Reibetanz ◽

Rainer Meffert ◽

...

Keyword(s):

Quality Of Life ◽

Soft Tissue ◽

Interdisciplinary Collaboration ◽

Life Quality ◽

Objective Evaluation ◽

Abdominoperineal Excision ◽

Soft Tissue Coverage ◽

Soft Tissue Reconstruction ◽

Sphincter Function

BACKGROUND: Preservation of quality of life regarding fecal continence after abdominoperineal excision (APE) in cancer is challenging. Simultaneous soft tissue coverage and restoration of continence mechanism can be provided through an interdisciplinary collaboration of colorectal and plastic reconstructive surgery. OBJECTIVE: Evaluation of surgical procedure and outcome combining soft tissue reconstruction using a central perforated vertical rectus abdominis myocutaneous flap (VRAM), implementing a perineostoma and restoring anorectal angle augmenting the levator ani by neurostimulated graciloplasty. METHODS: 14 Patients underwent APE due to cancer. In all patients coverage was achieved by pedicled VRAM and simultaneous pull-through descendostomy (perineostoma). 10 of those patients received a levator augmentation additionally. Postoperative complications, functional measures of continence as well as quality of life were obtained. RESULTS: Perineal minor complication rate was 43% without need of surgical intervention. All but one VRAM survived. Continence measures and disease specific life quality showed a good preservation of continence in most patients. CONCLUSION: The results present a complex therapy option accomplished by a collaboration of two highly specialized partners (visceral and plastic surgery) after total loss of the sphincter function and consecutive fecal insufficiency after APE.

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A NEW PARAMETER ESTIMATION METHOD FOR ONLINE SOFT TISSUE CHARACTERIZATION

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519416400194 ◽

2016 ◽

Vol 16 (08) ◽

pp. 1640019 ◽

Cited By ~ 6

Author(s):

JAEHYUN SHIN ◽

YONGMIN ZHONG ◽

JULIAN SMITH ◽

CHENGFAN GU

Keyword(s):

Soft Tissue ◽

Linear Regression ◽

Tissue Characterization ◽

Soft Tissues ◽

Unscented Kalman Filter ◽

Estimation Method ◽

Regression Method ◽

Linear Regression Method ◽

Non Linear

Dynamic soft tissue characterization is of importance to robotic-assisted minimally invasive surgery. The traditional linear regression method is unsuited to handle the non-linear Hunt–Crossley (HC) model and its linearization process involves a linearization error. This paper presents a new non-linear estimation method for dynamic characterization of mechanical properties of soft tissues. In order to deal with non-linear and dynamic conditions involved in soft tissue characterization, this method improves the non-linearity and dynamics of the HC model by treating parameter [Formula: see text] as independent variable. Based on this, an unscented Kalman filter is developed for online estimation of soft tissue parameters. Simulations and comparison analysis demonstrate that the proposed method is able to estimate mechanical parameters for both homogeneous tissues and heterogeneous and multi-layer tissues, and the achieved performance is much better than that of the linear regression method.

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Surgical-prosthetic treatment of large mandibular cysts

Vojnosanitetski pregled ◽

10.2298/vsp0303365d ◽

2003 ◽

Vol 60 (3) ◽

pp. 365-368

Author(s):

Ljubisa Dzambas ◽

Asen Dzolev

Keyword(s):

Quality Of Life ◽

Soft Tissue ◽

Bone Defect ◽

Tissue Regeneration ◽

Disease Patient ◽

Daily Activities ◽

Bone Tissue Regeneration ◽

Tissue Loss ◽

Mandibular Bone

This paper presents a combined surgical-prosthetic procedure of reconstructing mandibular bone defect in a 53 year old patient, following enucleation of a mandibular cyst (Cystectomy Partsch II). After a thorough diagnostic evaluation, a surgical procedure was planned with the particular attention to the nature of the disease, patient?s condition, size and extension of the cyst, tissue loss, and the possibilities of prosthetic management of a mandibular bone defect with partial postresection dental prosthesis. It is of great importance to point to the significance of teamwork of a maxillofacial surgeon and a specialist in prosthodontics. This kind of cooperation provided very effective and less risky soft tissue, as well as bone tissue regeneration (osteogenesis). The patient?s recovery was fast, and he could return to his daily activities and work without significant changes regarding quality of life after surgery and prosthetic treatment.

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Prosthodontic Rehabilitation of a Patient with Subtotal Maxillectomy using a Hollow Bulb Obturator

International Journal of Prosthodontics and Restorative Dentistry ◽

10.5005/jp-journals-10019-1042 ◽

2012 ◽

Vol 2 (1) ◽

pp. 24-28 ◽

Cited By ~ 1

Author(s):

Gita Rani ◽

Amarjeet Gambhir

Keyword(s):

Quality Of Life ◽

Case Report ◽

Clinical Case ◽

Soft Tissues ◽

Prosthetic Reconstruction ◽

Maxillary Defect ◽

Hollow Bulb Obturator

ABSTRACT Successful prosthetic reconstruction of hemimaxillectomy defects is a challenging procedure that requires multidisciplinary expertize to achieve acceptable function, speech and esthetics. Rehabilitation of an acquired maxillary defect improves the quality of life for the patient as close to normal as possible. Obturation of the defect depends on its volume and position of remaining hard and soft tissues, to be utilized for retention, stability and support for the prosthesis. The prosthesis should be simple to handle, easy to maintain, biocompatible, light in weight and convenient for future adjustments. This case report describes a clinical case of subtotal maxillectomy, which was successfully rehabilitated with a hollow bulb obturator. How to cite this article Rani G, Gambhir A. Prosthodontic Rehabilitation of a Patient with Subtotal Maxillectomy using a Hollow Bulb Obturator. Int J Prosthodont Restor Dent 2012; 2(1):24-28.

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Long-Term Outcomes of the Minimally Invasive Ponto Surgery vs. Linear Incision Technique With Soft Tissue Preservation for Installation of Percutaneous Bone Conduction Devices

Frontiers in Neurology ◽

10.3389/fneur.2021.632987 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ruben M. Strijbos ◽

Louise V. Straatman ◽

Tim G. A. Calon ◽

Martin L. Johansson ◽

Arthur J. G. de Bruijn ◽

...

Keyword(s):

Quality Of Life ◽

Soft Tissue ◽

Bone Conduction ◽

Tissue Preservation ◽

Implant Stability ◽

Implant Stability Quotient ◽

Incision Technique

Objective: Comparing the surgical outcomes of the Minimally Invasive Ponto Surgery (MIPS) technique with the linear incision technique with soft tissue preservation (LITT-P) for bone conduction devices after a follow-up of 22 months.Methods: In this multicenter randomized controlled trial, there was the inclusion of 64 adult patients eligible for unilateral surgery. There was 1:1 randomization to the MIPS (test) or the LITT-P (control) group. The primary outcome was an (adverse) soft tissue reaction. Secondary outcomes were pain, loss of sensibility, soft tissue height/overgrowth, skin sagging, implant loss, Implant Stability Quotient measurements, cosmetic scores, and quality of life questionnaires.Results: Sixty-three subjects were analyzed in the intention-to-treat population. No differences were found in the presence of (adverse) soft tissue reactions during complete follow-up. Also, there were no differences in pain, wound dehiscence, skin level, soft tissue overgrowth, and overall quality of life. Loss of sensibility (until 3-month post-surgery), cosmetic scores, and skin sagging outcomes were better in the MIPS group. The Implant Stability Quotient was higher after the LITT-P for different abutment lengths at various points of follow-up. Implant extrusion was nonsignificantly higher after the MIPS (15.2%) compared with LITT-P (3.3%).Conclusion: The long-term results show favorable outcomes for both techniques. The MIPS is a promising technique with some benefits over the LITT-P. Concerns regarding nonsignificantly higher implant loss may be overcome with future developments and research.Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT02438618.

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Orthopedic treatment in cancer patients with maxillofacial pathology

South Russian Journal of Cancer ◽

10.37748/2686-9039-2021-2-2-3 ◽

2021 ◽

Vol 2 (2) ◽

pp. 22-33

Author(s):

I. V. Pustovaya ◽

M. A. Engibaryan ◽

P. V. Svetitskiy ◽

I. V. Aedinova ◽

V. L. Volkova ◽

...

Keyword(s):

Quality Of Life ◽

Soft Tissues ◽

Malignant Tumors ◽

Social Adaptation ◽

Research Centre ◽

Orthopedic Treatment ◽

National Medical ◽

Upper Jaw ◽

The Aesthetic

Relevance. Staged orthopedic treatment was used to improve the quality of life of patients who underwent radical maxillofacial surgeries for cancer.Patients and methods. 197 patients receiving treatment for maxillofacial cancer were observed at the Department of head and neck tumors, National Medical Research Centre for Oncology of the Ministry of Health of Russia, in 1998- 2018. All patients underwent radical surgical treatment resulting in postoperative defects of the upper jaw, soft tissues of the zygomatic- buccal-orbital region, nose, or auricle.Results. Removable obturator prostheses with various supporting and retaining elements were made for 159 (80.7 %) patients. Individual facial prostheses were made for 38 (19.3 %) patients: 17 (44.7 %) – external orbital prostheses, 14 (36.8 %) – external nasal prostheses, 6 (15.8 %) – external zygomatic- buccal-orbital prostheses, 1 (2.7 %) – external auricle prosthesis. Combined prostheses were made for 4 patients– removable upper jaw obturator and nose prosthe[1]sis; removable upper jaw obturator and eye prosthesis. Combined prostheses were fixed to each other using magnets. The results of maxillofacial prosthetics were evaluated according to the aesthetic requirements of the patients and their quality of life. Maxillofacial prostheses allowed a complete restoration of chewing, swallowing, and speaking, restored facial deformation, and improved the appearance of patients.Conclusions. Timely and comprehensive orthopedic treatment of patients with postoperative maxillofacial defects after radical surgeries for malignant tumors takes the main place in the complex of rehabilitation measures. Early elimination of extensive defects is aimed at maximum restoration of oral dysfunctions and appearance preservation. The apparent advantages of maxillofacial prostheses involve improvement of social adaptation and the quality of life of patients, which promotes complete rehabilitation and a return to socially useful activities.

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