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The Concept of Biocompatibility
Published in Antonietta Morena Gatti, Stefano Montanari, Advances in Nanopathology From Vaccines to Food, 2021
Antonietta Morena Gatti, Stefano Montanari
The bulk material may have passed all tests and be declared biocompatible, but that is not the case with its debris. As a matter of fact, they are generally attacked by macrophages and moved to other parts of the body. Generally speaking, and with some exceptions, biological materials (bone, cells, etc.) can reconstruct themselves, but synthetic materials are always unable to do so. What they do is degrade, or due to the surface interaction with body fluids, they can change some of their properties as happens, for example, in the case of corrosion, an oxidation process which occurs also inside the body at 37°C in an aqueous environment full of chemicals and crossed by weak electric currents. As a rule, degradation and oxidation products are not compatible, and a relatively frequent example of that incompatibility is represented by the release of iron hydroxide, a quite common event when iron-based matter is for any reason inserted into the body. Besides having grown incompatible, the prosthesis becomes so more and more useless. In some circumstances, a prosthesis may remain relatively biocompatible but stops functioning as it should. This is the case, for example, of the formation of bacterial biofilms or a so-called pannus on heart valve prostheses, that is, an ingrowth of tissue.
Twenty-Year Follow-Up Study on Patient-Fitted Temporomandibular Joint Prosthesis: The Techmedia/TMJ Concepts Device
Published in Niall MH McLeod, Peter A Brennan, 50 Landmark Papers every Oral & Maxillofacial Surgeon Should Know, 2020
The median number of previous surgeries was 3 (IQR 4, range 0–27). Postoperative pain and limitation in mouth opening were correlated to number of previous surgeries. None of the 56 study patients exhibited prosthesis failure.
The cardiac system: Physiology and principles of care
Published in Judy Bothamley, Maureen Boyle, Medical Conditions Affecting Pregnancy and Childbirth, 2020
Women with a history of heart disease should receive preconception advice before each pregnancy. Most congenital heart conditions, even following successful repairs in childhood, need full evaluation between pregnancies, even if the previous pregnancy was uneventful. A successful repair of a condition in childhood does not mean it will continue to perform well into and through adult life, and the physiological changes in pregnancy may compromise a woman’s cardiovascular system whether she has had a previous repair of a congenital defect or has a benign condition. It is undoubtedly true that each year women die following heart disease complicating pregnancy, but the amount of stress a pregnancy puts on an abnormal heart condition is largely unknown, although there is evidence in certain specific conditions (Warnes, 2006a). In addition, many conditions are progressive, and prostheses can wear out. A full assessment of her condition, possible surgery pre-pregnancy (and use of biological valves rather than mechanical valves in order to avoid coagulation issues) (Warnes, 2006b) may improve pregnancy success rate. Surgical correction of the anomaly, if done before pregnancy, can give a better outcome. Predictors of adverse outcomes include poor maternal functional status, myocardial dysfunctions, significant aortic or mitral valve stenosis and a history of arrhythmias or cardiac events.
Psychosocial factors among patients undergoing orbital exenteration
Published in Clinical and Experimental Optometry, 2023
Neelima Balakrishnan, Sahil Agrawal, Rachna Bhargava, Veena Jain, Neelam Pushker, Rachna Meel, Mandeep S. Bajaj
Rehabilitation following exenteration includes fitting the patient with an ocular prosthesis, which has psychological consequences of its own. Significant distress was noted in a considerable proportion of patients rehabilitated with ocular prosthesis.34 Dissatisfaction with the prosthesis may also impact its use. In one study, it has been found that only 11.8% of patients who underwent sub-total exenteration with an ocular prosthesis did not wear an eye patch. This meant that despite attempts to rehabilitate the patient with prosthesis, the patients still chose to hide the prosthesis due to their dissatisfaction with its appearance.35 This may limit the willingness of a patient to follow-up as well as the compliance to further treatment. The psychosocial impact and satisfaction with the prosthesis in spectacle prosthesis wearers for more than 3 months duration after exenteration was also studied (group II). The duration of use of prosthesis ranged in the patients from 3 to 6 months and the mean duration was 4.25 months. The severity of depression was moderately severe in 70% patients and anxiety was mild in 50% and moderate in 40% patients.
Advances in additive manufacturing processes and their use for the fabrication of lower limb prosthetic devices
Published in Expert Review of Medical Devices, 2023
Shaurya Bhatt, Deepak Joshi, Pawan Kumar Rakesh, Anoop Kant Godiyal
Prosthetic devices are used to physically support a person with a disability, caused due to loss of a limb or a certain portion of limb or a body part due to disease or trauma. Prosthetic devices can replace the missing part in the body of a person and help to regain the working capabilities of the lost part. Prostheses can be of many types, such a foot prosthesis, hand prostheses, and many more. The part of the limb that is left after loss is known as residual limb. A prosthesis socket acts as inter-connection between the prosthesis and residual limb, and helps to transfer load and motion from the residual limb to the prosthesis. The naming of prostheses is carried out based on joint and limb involved. Four common nomenclatures of prostheses are Above Elbow (AE), Below Elbow (BE), Above Knee (AK), and Below Knee (BK). Prostheses can also be named based on the bone involved, like transradial prosthesis, transhumeral prosthesis, transfemoral prosthesis, and transtibial prosthesis, as were used in various studies [1–4]. It is estimated that 25.5 million people in the world need prosthetic/orthotic devices [5]. In India, 2.21% of total population is disabled, in which 20% has disability related to movement [6].
Custom ocular prosthesis-related concerns: patient feedback survey-based report vis-à-vis objective clinical grading scales
Published in Orbit, 2021
Tarjani Vivek Dave, Arpita Nayak, Mansha Palo, Yashwanth Goud, Dharani Tripuraneni, Sachin Gupta
However, the second most common concern was indeed watering, crusting and discharge. This does remain a significant concern in most patients using and ocular prosthesis and highlights the need for research into newer, local milieu friendly materials for the fabrication of ocular prosthesis or strategies for surface coating of the prosthesis with hydrophilic materials25 or sustained release of steroid in the socket tissues to control the inflammation. The additional concerns with prosthesis wear in the patients in the age group of 20–40 years were for colour match of the prosthesis, comfort with prosthesis wear and retention of the prosthesis. This resonates with the fact older participants are less concerned about appearance as studied by Pine et al.4 and also emphasises the fact that younger participants may be more attentive to detail.