Effect of Aging on Tensile and Chemical Properties of Polylactic Acid and Polylactic Acid-Like Polymer Materials for Additive Manufacturing.

Additive manufacturing, with its fast development and application of polymeric materials, led to the wide utilization of polylactic acid (PLA) materials. As a biodegradable and biocompatible aliphatic polyester, produced from renewable sources, PLA is widely used in different sectors, from industry to medicine and science. The aim of this research is to determine the differences between two forms of the PLA material, i.

Influence of Aging on the Flexural Strength of PLA and PLA-X 3D-Printed Materials.

The three-point bending test is a valuable method for evaluating the mechanical properties of 3D-printed biomaterials, which can be used in various applications. The use of 3D printing in specimen preparation enables precise control over material composition and microstructure, facilitating the investigation of different printing parameters and advanced materials. The traditional approach to analyzing the mechanical properties of a material using a three-point bending test has the disadvantage that it provides only global information about the material's behavior.

A Comprehensive Mechanical Examination of ABS and ABS-like Polymers Additively Manufactured by Material Extrusion and Vat Photopolymerization Processes.

Additive manufacturing technologies have developed rapidly in recent decades, pushing the limits of known manufacturing processes. The need to study the properties of the different materials used for these processes comprehensively and in detail has become a primary goal in order to get the best out of the manufacturing itself. The widely used thermoplastic polymer material acrylonitrile butadiene styrene (ABS) was selected in the form of both filaments and ABS-like resins to investigate and compare the mechanical properties through a series of different tests.

The effect of time on mechanical properties of biocompatible photopolymer resins used for fabrication of clear dental aligners.

Clear dental aligners are used for treating orthodontic anomalies (misaligned teeth, inappropriate contact between upper and lower teeth etc.), minor irregularities and bruxism. Using additive manufacturing technologies clear dental aligners are made of biocompatible photopolymer, using a vat photopolymerization technology.

Morphogenetic Variability as Potential Biomarker of Neurogenic Lesion Degree in Children with Spina Bifida.

Aims: In this study we analyzed the degree of genetic homozygosity among spina bifida patients with different degrees of neurogenic lesion ( = 82), as well as their clinical and neurological characteristics, compared to healthy control individuals ( = 100).

Methods: According to clinical and electromyographic findings, we separately assessed the type of neurogenic lesion (paresis or paralysis). Regarding the degree of neurogenic lesion, patients were classified into three groups: mild, moderate and severe.

Reliability, Consistency and Temporal Stability of Alberta Infant Motor Scale in Serbian Infants.

Our study aimed to analyze the reliability, consistency, and temporal stability of the Alberta Infant Motor Scale (AIMS) in Serbian infants. Additionally, we aimed to present a percentile distribution of AIMS in the tested population. The prospective study included 60 infants that were divided into three age groups: 0-3 months, 4-7 months, and 8-14 months.

Case-series study of hepatic echinococcal cysts in Serbia: viability of scolices, seropositivity and epidemiological characteristics.

Cystic echinococcosis (CE) is an endemic helminthic disease caused by infection with Echinococcus granulosus metacestodes. Although CE is endemic in the Balkan region, the exact epidemiology remains unknown. We conducted a case-series study with the aim of evaluating the correlation between seropositivity, socio-epidemiological data, pre-operative treatment with albendazole and viability of protoscolices in human hepatic hydatid cysts.

Results of open tibial fracture treatment using external fixation.

Introduction: Open lower leg fractures are the most common open fractures of the locomotor system and their treatment is associated with a number of complications.

Objective: The aim of the paper was to present the results of the treatment of 68 patients with open lower leg fractures, as well as the complications that accompany the treatment of these fractures.

Methods: In the analyzed group, there were 45 (66.

Treatment of open tibial fracture with bone defect caused by high velocity missiles: a case report.

Introduction: Tibia fracture caused by high velocity missiles is mostly comminuted and followed by bone defect which makes their healing process extremely difficult and prone to numerous complications.

Case Outline: A 34-year-old male was wounded at close range by a semi-automatic gun missile. He was wounded in the distal area of the left tibia and suffered a massive defect of the bone and soft tissue.

Comparative analysis of autodermal graft and polypropylene mesh use in large incisional hernia defects reconstruction.

Background: Large defects of the abdominal wall caused by incisional hernia still represent a challenging problem in plastic, reconstructive, and abdominal surgery. For their successful tension-free repair a proper selection of reconstructive material is essential. In the last decades, the use of synthetic meshes was dominant while biological autodermal grafts were rarely used.

Evaluation of inflammatory markers after orthopedic surgical intervention in children.

Objective: The study aim was to evaluate inflammation markers values (C-reactive protein (CRP), Erythrocite sedimentation (ES), White blood cells count (WBC)) in surgically treated pediatric patients with diagnosed developmental displasia of the hip or Perthes disease before and after operation.

Methods: We have evaluated 43 children (20 patients were with diagnosed unilateral developmental displasia of the hip while 23 had Perthes disease). Blood samples were drown at the admission and 5 days after admission, and further inflammatory parameters were analyzed: ES (mm/hour), CRP (mg/L) and WBC (x1000/mm3) count.

[Open segmental fractures of the tibia treated by external fixation].

Introduction: Open segmental fractures of the tibia are rare but severe injuries. In these fractures the wide zone of injury (damage of all structures of the lower leg) creates very unsuitable biological conditions for healing of the fracture.

Objective: The aim of our work was to present the results of treatment of patients with segmental open fractures of the tibia treated by external fixation.

[Surgical treatment of tibial nonunion after wounding by high velocity missile and external fixators: a case report].

Introduction: The missiles of modern firearms can cause severe fractures of the extremity. High velocity missile fractures of the tibia are characterized by massive tissue destruction and primary contamination with polymorphic bacteria. Treatment of these fractures is often complicated by delayed healing, poor position healing, nonhealing and bone tissue infection.

Correlation of ABO and Rh blood groups with transfusion administration and fever onset after hip surgery in children.

Objective: Aim of our study was to evaluate distribution of ABO and Rh blood type groups in children after hip surgery regarding transfusion administration and fever presence.

Methods: Four types of ABO blood groups (A; B; AB; O) and 2 types of Rh blood groups (Rh+; Rh-) were evaluated in group with administered transfusion (tr+) and without given transfusion (tr-); and in group with fever (fev+) and without fever (fev-), in 146 children after hip surgery. Tr+ and fev+ groups were divided into 3 groups (0-24h; 25-48h; 49-72h): for tr+ group (Group 1, Group 2, Group 3), and for fev+ group (Group A, Group B, Group C).

Distribution of affected muscles and degree of neurogenic lesion in patients with spina bifida.

Introduction: Patients with spina bifida in the lumbosacral region usually have various degrees of motor and sensory dysfunctions of the lower extremities and anal sphincter. The aim of our study was to evaluate the distribution and differences in frequencies of affected muscles, number of affected muscles and degree of neurogenic lesion between patients with spina bifida occulta (SBO) and spina bifida aperta (SBA).

Material And Methods: In 100 patients with SB, 6 muscles in the lower limbs were separately analysed.

[External fixation in the treatment of shooting proximal humeral fracture with bone defect: a case report].

Introduction: Shooting injuries of shoulder with destruction of proximal humerus are rare and severe orthopaedic injuries.

Case Outline: A 74-year-old patient was wounded at close range by a shotgun. He was wounded in the left shoulder and suffered a massive defect of the proximal humerus and soft tissue.

Treatment of subtrochanteric femoral fractures using Selfdynamisable internal fixator.

Background: Surgical treatment is the preferred method for treating subtrochanteric femoral fractures and the variety of extramedullary and intramedullary implants continues to evolve. The purpose of our study was to retrospectively evaluate the clinical and radiological results of subtrochanteric fractures that are treated with the Selfdynamisable internal fixator.

Methods: From January 2000 to January 2004, we treated 49 consecutive patients who had subtrochanteric fractures.

Physical therapy of non-neurogenic voiding dysfunction in children with occult spinal dysraphism.

Background: In children with occult spinal dysraphism one of the symptoms is disbalance in bladder emptying and filling. Goal of our study was to estimate the correlation of medicamentous treatment alone and combined medicamentous and physical treatment in patients that are diagnosed with occult spinal dysraphism with non-neurogenic bladder dysphunction.

Methods: We evaluated 69 patients aged from 4 to 12 years treated at the University children's Hospital in Belgrade during 2005-2008 years period.

[Penetrating injury of the lungs and multiple injuries of lower extremities caused by aircraft bombs splinters].

Introduction: Injuries caused by aircraft bombs cause severe damages to the human body. They are characterized by massive destruction of injured tissues and organs, primary contamination by polymorph bacterial flora and modified reactivity of the body. Upon being wounded by aircraft bombs projectiles a victim simultaneously sustains severe damages of many organs and organ systems due to the fact that a large number of projectiles at the same time injure the chest, stomach, head and extremities.

Treatment of open tibial shaft fracture with soft tissue and bone defect caused by aircraft bomb--case report.

Introduction: Aircraft bombs can cause severe orthopaedic injuries. Tibia shaft fractures caused by aircraft bombs are mostly comminuted and followed by bone defects, which makes the healing process extremely difficult and prone to numerous complications. The goal of this paper is to present the method of treatment and the end results of treatment of a serious open tibial fracture with soft and bone tissue defects resulting from aircraft bomb shrapnel wounds.

[Treatment of multiple fractures in a patient wounded by aircraft bombing].

Introduction: Aircraft cluster bombs can cause severe fractures characterized by extensive destruction of affected tissues and organs.

Case Outline: We present the methods and results of treatment of multiple fractures (left supracondilar humeral fracture, comminuted fracture of the distal right tibia, fracture of right trochanter major without dislocation and fracture of the right second metacarpal bone) in a 24-year old soldier after multiple wounding by a cluster bomb. After short pre-operative preparation a surgical debridement of all wounds was done in general anaesthesia and the fractures of the humerus and tibia were stabilized with the Mitkovic-type external fixator after adequate reposition.

Congenital muscular torticollis in children: distribution, treatment duration and out come.

Aim: The aim of the study was to evaluate the proportion of left and right congenital muscular torticollis (CMT) in both genders and age groups of the patients as well as to evaluate the duration of physical therapy and treatment outcome in observed population.

Methods: In our study, 980 children with CMT without hematoma were treated at University children's Hospital of Belgrade (Serbia). They were divided into 2 groups: group with left torticollis and group with right torticollis.

[Fasciocutaneous perforators of the lower leg--anatomic study and clinical significance].

Background/aim: Soft tissue defects of the lower leg, especially in its distal third, still remain a challenging problem in reconstructive surgery. The aim of this study was to examine septocutaneous system of lower leg vascularization, quantitatively and qualitatively, which is the basis of fasciocutaneous and neurocutaneous flaps.

Methods: Septocutaneous systems a.

[Morphometrical analysis of bone marrow metamyelocyte in pernicious anemia].

Introduction: In pernicious anemia besides the presence of megaloblasts in the bone marrow, changes in myeloid series were seen; being the most evident among the metamyelocyte. The aim of this study was to perform the quantification of metamyelocyte of the bone marrow in pernicious anemia.

Material And Methods: Between 2000-2006 in the Clinic of Hematology-Nis, 68 patients with pernicious anemia were examined and 30 with dyspeptic syndrome (control group).