EDTA assisted synthesis of HA nanoparticles and Cobalt-HA nanocomposites

Nano biomaterials such as polymers, ceramics and metals are widely used in bone for regenerative therapies, bone grafts and tissue engineering as well as for temporary or permanent implants to stabilize fractures and replace joints. Bioceramics are specifically developed to replace parts of living system due to its biocompatibility. Hydroxyapatite (HA)Ca10(PO4)6(OH)2 used as a bone substitute material with stoichiometric composition i.e.,Ca/P(ratio) 1.67, which is similar to the mineral phase of the human bone. In this present work, (EDTA) ethylene diamine tetra acetic acid assisted as a capping agent for the synthesis of nano hydroxyapatite and cobalt substituted hydroxyapatite nanocomposites by sol gel method. The synthesized nano-HA powder and Co-HA nanocomposites are further characterized by using FTIR, XRD, SEM, EDAX and anti-bacterial activity. XRD analysis of HA Nanoparticles and Co-HA Nanocomposites, shows the strongest 2θ values at 32.1°,25.91°and at 32.1°, 10.1°, 16.6° respectively. SEM morphology predicts an elongated spherical morphology for HA Nanoparticles and Co-HA Nanocomposites. The elemental composition was confirmed with EDAX analysis and the FTIR spectrum indicates the functional groups of the synthesized compounds. The antibacterial activity was analyzed for both the gram-positive and the gram-negative bacteria’s.

Accidental Magnetic Resonance Imaging Activation of Carbon Dioxide Tissue Expanders

Implant-based reconstruction is the most common form of breast reconstruction following mastectomy. It is most often performed in 2 stages using saline-based tissue expanders, which are then exchanged for permanent implants. Serial expansions are performed by accessing a port in the office, an inconvenient and sometimes painful process. A carbon dioxide tissue expander is a device that provides a needle-free, patient-controlled expansion utilizing a remote-controlled CO2 canister. While a patient-controlled expansion offers convenience, given that the CO2 reservoir holds approximately 1500 mL of gas, the potential for malfunction resulting in an uncontrolled expansion in unique to this device. The authors present a case report of a patient with bilateral pre-pectoral tissue expanders who underwent magnetic resonance imaging, resulting in uncontrolled expansion. Level of Evidence: 5

Results at 3-year follow-up of totally extraperitoneal (TEP) hernia surgery with long-term resorbable mesh

Introduction Synthetic non-resorbable mesh is almost standard in hernia surgery. However, several studies have showed negative effects of permanent implants such as chronic inflammation and complications involving different organs bordering the mesh. Such complications can raise the risk of chronic post-operative pain (CPP). Recently promising results regarding CPP have been published in patients with Lateral Inguinal Hernia (LIH) using a slowly resorbable mesh in Lichtenstein technique. For this reason the aim of the present study was to find the effect of a slowly resorbable implant on the long-term rate of hernia recurrence and chronic post-operative pain in patients with LIH repaired with TEP procedure. Methods Prospective pilot study of TEP repair using TIGR® Matrix Surgical Mesh in 35 primary LIH. At 3-year follow-up the Visual Analogue Scale (VAS) and the Inguinal Pain Questionnaire were employed to assess pain. Recurrence was determined by ultrasound and clinical examination. Results All patients completed the pain questionnaires but one patient did not attend the planned clinical examination for the 3-year follow-up. No patients had CPP, as defined in the World Guidelines for Groin Hernia Management. Almost all patients had lower VAS score in any activity 3 years following surgery in comparison to the preoperative period. Three patients (8.8%) suffered symptomatic recurrence during the 3-year follow-up. Conclusion TEP repair in patients with LIH using a synthetic long-term resorbable mesh was found to be encouraging respecting chronic post-operative pain at 3-year follow-up but at the cost of an increased risk of recurrence.

RTHP-32. FIRST EXPERIENCE WITH GAMMATILE PERMANENT IMPLANTS FOR RECURRENT BRAIN TUMORS

GammatileTM permanent brachytherapy implants have been FDA cleared for patients with recurrent brain tumors. We report our experience with the first 6 patients with recurrent high grade primary brain tumors treated with re-resection and implantation. Each tile contains 4 encapsulated radioactive Cs-131 seeds embedded in collagen. To determine the number of tiles needed, the potential tumor cavity surface area was estimated using the preoperative MRI images. The anticipated cavity surface area was calculated, the surface area of anticipated surgical approach was subtracted. This area was divided by 40mm2 (tile area) and this number of tiles were ordered. At the time of surgery, after maximal safe tumor resection, tiles were placed into the resection cavity and the surgical cavity closed as usual. On post-implant day 1, CT and MRI scans were performed. The cavity was contoured, then expanded by 5mm to create HRCTV. T1 MRI enhanced lesions were contoured as residual GTV (GTVr). A dose of 60Gy over the course of treatment was prescribed to HRCTV. In each of these 6 cases, over 95% of the HRCTV was covered by the 60Gy isodose surface, and GTVr D90 ranged from 22.9Gy to 113.8Gy. The additional time required for the tile placement in all cases was less than 10 minutes. Post-operatively exposure rates at 1m were less than 6 mR/hr (ranging from 1.3 to 3.2mR/h). Permanent GammaTile for recurrent brain tumors is a viable option for selected previously irradiated patients who are operative candidates. Benefits include irradiation of the tumor bed starting immediately after resection with no need to wait for wound healing, and no need to subsequently surgically remove the tile. We were able to accurately predict the number of tiles needed, although in one case collagen spacers were utilized. Due to low exposure rates, radiation protection issues are very manageable.

Orbital Floor Reconstruction: A Comparison of Outcomes between Absorbable and Permanent Implant Systems

There are distinct advantages and disadvantages between bioresorbable and permanent implants in orbital floor reconstruction. Our aim was to compare the outcomes and complications of resorbable implants and permanent implants in orbital floor fracture repair. A retrospective chart review was performed on all patients who underwent orbital floor fracture repair at a rural, tertiary care center from 2011 through 2016. Main outcome measures included improvement in diplopia, ocular motility, enophthalmos, hypoglobus, and infraorbital nerve sensation. A total of 87 patients underwent orbital floor reconstruction. After exclusion criteria were applied, 22 patients were included in the absorbable implant cohort, and 20 patients in the nonabsorbable implant cohort. All absorbable implants were composed of poly L-lactide/poly glycolide/poly D-lactide (PLL/PG/PDL), and nonabsorbable implants included both titanium/porous polyethylene (Ti/PPE) composite and titanium (Ti) mesh. Mean fracture surface area was 2.1 cm2 (standard deviation [SD]:± 0.9 cm2, range: 0.4–3.6 cm2) for the absorbable implant group and 2.3 cm2 (SD: ± 1.1 cm2, range: 0.6–4.4 cm2) for the nonabsorbable implant group ( p = 0.58). There were no significant differences in diplopia, ocular motility, enophthalmos, hypoglobus, and infraorbital nerve sensation between absorbable and nonabsorbable implant groups. The mean follow-up time for absorbable and nonabsorbable implant groups was 622 (SD ± 313) and 578 (SD ± 151) days respectively ( p = 0.57). For moderate-size orbital floor fracture repairs, there is no difference in outcomes between absorbable implants consisting of PLL/PG/PDL and nonabsorbable implants consisting of Ti mesh or Ti/PPE combination.

Aspects of an automatic system of implants of radioac-tive seeds and anatomic object simulator for tests in prostate brachytherapy.

This work presents the development of an automatic radioactive seed implantation system (PSIS). PSIS may assist the testing permanent implants procedure in the prostate. These tests will be important in measurements of absorbed doses in the pelvic structures, involving the organs and tissues at risk to improve planning, seed positioning and dosimetry. The automated Prostate Seed Implant System (PSIS) has been designed to meet operational needs, which offers the freedom when positioning the brachytherapy needle inside the treatment area ensuring repeatability and fidelity to the planned treatment. Both the ultrasound probe and the seed implant needle are driven by stepper motors, ATMEGA microcontroller, bearings, aluminum shafts and a GUI (Graphical User Interface). Movement of both the probe and the needle holder was performed by fixed spindle on a threaded rod going through a stepper motors by a coupling. These engines were chosen due to the necessity of movements precision that these types of motors provide. The project was developed and the PSIS prototype was assembled. The prototype presented acceptable operating characteristics for prostate implants. The advantage of this system is that the automation of the application provides an accurate positioning and movement of both probe and seed application. In addition to this study, seeds implantation tests will be performed, and such tests will be essential in protocol validation processes.

Additive Manufacturing for Guided Bone Regeneration: A Perspective for Alveolar Ridge Augmentation

Three-dimensional (3D) printing has become an important tool in the field of tissue engineering and its further development will lead to completely new clinical possibilities. The ability to create tissue scaffolds with controllable characteristics, such as internal architecture, porosity, and interconnectivity make it highly desirable in comparison to conventional techniques, which lack a defined structure and repeatability between scaffolds. Furthermore, 3D printing allows for the production of scaffolds with patient-specific dimensions using computer-aided design. The availability of commercially available 3D printed permanent implants is on the rise; however, there are yet to be any commercially available biodegradable/bioresorbable devices. This review will compare the main 3D printing techniques of: stereolithography; selective laser sintering; powder bed inkjet printing and extrusion printing; for the fabrication of biodegradable/bioresorbable bone tissue scaffolds; and, discuss their potential for dental applications, specifically augmentation of the alveolar ridge.