A novel pedicle screw design to maximize screw-bone interface strength using finite element analysis and design of experiment techniques.

Study Design: Basic study.

Purpose: This study aimed to utilize finite element (FE) analysis and design of experiment (DoE) techniques to propose and optimize a novel pedicle screw design and compare its pull-out force with that of a control device.

Overview Of Literature: Pedicle screw-based fixation is the gold-standard treatment for spine diseases, particularly in fusion procedures.

Drug eluting bioactive glass ceramics for fusion in spondylodiscitis: a pilot study.

Retrospective observational study. To determine the efficacy and safety of bioactive glass ceramics mixed with autograft in the treatment of spondylodiscitis. Thirty-four patients with spondylodiscitis underwent surgery using autologous bone graft augmented by antibiotic loaded bioactive glass ceramic granules.

3D-bulk to nanoforms of modified hydroxyapatite: Characterization and osteogenic potency in an in vitro 3D bone model system.

Synthetic bioceramics are replacing conventional methods of treating bone defects with autografts owing to the high demand of bone substitutes, with their Surface topography and size contributing to favor cytocompatibility in tissue regeneration. This experimental study deals with the comparative evaluation of the physical characterizations of four different in-house synthesized bioceramics from 3D-bulk to nanoforms of hydroxyapatite (HA), Biphasic calcium phosphate (BCP), Strontium doped hydroxyapatite (SrHA) and Silica coated hydroxyapatite (HASi) and also simultaneously evaluates adhesion, proliferation and osteogenic differentiation of rabbit adipose derived mesenchymal stem cells (RADMSCs) on these biomimetic ceramic niches. The osteogenic induced cells grown on 3D scaffolds for a period of 7, 14, 21, and 28 days were analyzed for their viability (MTT, LDH, live-dead assays), morphology (SEM), proliferation (Cytox-Red) and osteogenic differentiation (ALP, osteocalcin expression).

Hydroxyapatite carriers as drug eluting agents-An analysis.

Introduction: Hydroxyapatite based drug carriers offer a customized alternative to the delivery of pharmacologic agents in the osseous skeleton. They have an added advantage of being biocompatible and osteoconductive. This in vitro study aims to quantify the drug eluting properties of HA granules by spectrophotometry.

Inducing apatite pre-layer on titanium surface through hydrothermal processing for osseointegration.

Commercially available titanium (Ti) having high mechanical strength and a low area of cross-section can be adequately exploited for minimally invasive dental implantation. Current directions in clinical dental implant therapy focus on endosseous dental implant surfaces with nanoscale topographies using easy and economical processing approaches. The present study describes the generation of a novel nanolayer nucleating agent on the surface of Ti implant for early endosseous after implantation.

Ceramic Bone Graft Substitutes do not reduce donor-site morbidity in ACL reconstruction surgeries: a pilot study.

Introduction: Anterior knee pain is a major problem following Bone-patellar-tendon-bone graft (BPTB) use in anterior cruciate ligament (ACL) reconstruction. We hypothesized that filling the donor defect sites with bone-graft substitute would reduce the anterior knee symptoms in ACL reconstruction surgeries.

Material And Methods: Patients operated for ACL-deficient knee between March 2012 and August 2013 using BPTB graft were divided into two treatment groups.

Preparation of hydroxyapatite porous scaffold from a 'coral-like' synthetic inorganic precursor for use as a bone substitute and a drug delivery vehicle.

A novel surfactant free hydrothermal method was developed for the preparation of large hydroxyapatite scaffolds. Synthetic calcium carbonate (calcite) was used as the starting material which when mixed with an inorganic setting solution containing phosphoric acid and sodium hydroxide forms the porous precursor body with pore size 20-700 μm. The porous precursor body was then hydrothermally converted to hydroxyapatite scaffolds when treated in basic phosphate solution of pH 10.

Bioactive nano-fibrous scaffold for vascularized craniofacial bone regeneration.

There has been a growing demand for bone grafts for correction of bone defects in complicated fractures or tumours in the craniofacial region. Soft flexible membrane like material that could be inserted into defect by less invasive approaches; promote osteoconductivity and act as a barrier to soft tissue in growth while promoting bone formation is an attractive option for this region. Electrospinning has recently emerged as one of the most promising techniques for fabrication of extracellular matrix such as nano-fibrous scaffolds that can serve as a template for bone formation.

Occurrence of vancomycin-resistant Staphylococcus aureus in the oral cavity of patients with dental caries.

Oral streptococci are the major group of microbes isolated from oral microflora. They represent frequent pathogens of infective endocarditis (IE), and it is assumed that in most of the cases oral streptococci are acquired via mucosa layer of oral cavity. Staphylococcus aureus is also frequently isolated from IE as it accounts for 20%-30% of all cases.

Effect of surface-modified superparamagnetic iron oxide nanoparticles (SPIONS) on mast cell infiltration: An acute in vivo study.

Extensive use of superparamagnetic iron oxide nanoparticles (SPIONS) in theranostics prompted us to investigate the acute changes in cell morphology and function following intravenous administration of surface-modified SPIONS in a rat model. Dextran-coated (DEX) and polyethylene glycol-coated (PEG) SPIONS were synthesized and characterized, and cytocompatibility was evaluated in vitro. Haematological, histopathological, ultrastructural and oxidative stress analyses were carried out 24h post intravenous administration in vivo.

Development, characterization and comparison of two strontium doped nano hydroxyapatite molecules for enamel repair/regeneration.

Objectives: Enamel damage resulting or arising from/associated with orthodontic treatment such as white spot lesions and surface deterioration after debonding brackets along with incipient carious lesions are considered problems not amenable for routine restorations due to its invasive nature. The present study was aimed at synthesizing and characterizing nHAp and 25 and 50 mol% strontium nHAp as a surface application modality for dental enamel remineralization/repair.

Methods: 25 and 50 mol% Sr nHAp was synthesized and characterized in comparison with custom made pure nHAp initially with the help of transmission and scanning electron microscopy as well as toxicological assessment.

Combined Treatment Effects Using Bioactive-Coated Implants and Ceramic Granulate in a Rabbit Femoral Condyle Model.

Background: Resolution of peri-implant defects resulting from implant placement in the freshly extracted site demands for a bone graft substitute that stimulates bone regeneration and hence facilitates implant integration. In view of this, the addition of silica to hydroxyapatite (HASi) could enhance the bioactive behavior of ceramic materials and implant surfaces coated with bioactive ceramics might benefit the interaction between bone and implant.

Purpose: To evaluate the bone response to implants coated with hydroxyapatite-silica (HASi) or hydroxyapatite (HA) and either or not combined with HASi and HA ceramic bone substitute particles, respectively, on bone-to-implant contact (BIC) and bone formation using a rabbit femoral condyle implant model with a gap design.

Development of an injectable bioactive bone filler cement with hydrogen orthophosphate incorporated calcium sulfate.

Calcium sulfate cement (CSC) has emerged as a potential bone filler material mainly because of the possibility of incorporating therapeutic agents. Delivery of the cement through a needle or cannula will make it more useful in clinical applications. However, it was not possible to make CSC injectable because of the inherent lack of viscosity.

Triphasic ceramic scaffold in paediatric and adolescent bone defects.

We evaluated novel triphasic hydroxyapatite tricalcium phosphate calcium silicate scaffold (HASi) in the management of paediatric bone defects. Their main advantage is considered to be adequate strength and stimulation of bone formation without resorting to autograft. A total of 42 children younger than 16 years of age were recruited over a period of 1 year and were treated with this synthetic bone substitute as a stand-alone graft for pelvic, femur, calcaneal and ulnar osteotomies, cystic bone lesions, subtalar arthrodesis and segmental bone defects.

Pulsed laser deposition of hydroxyapatite on nanostructured titanium towards drug eluting implants.

Titania nanotubes grown on titanium substrates by electrochemical anodization in glycerol-ammonium fluoride-water system were used to develop efficient drug carrying implants upon coating hydroxyapatite (HA) ceramic. The nanostructured surfaces achieved by anodization were caped with HA crystallites by pulsed laser deposition. The implant substrates were studied for their drug carrying capacity using gentamicin as a model.

Pulsed laser deposition and in vitro characteristics of triphasic - HASi composition on titanium.

Pulsed laser deposition was used to deposit bioactive triphasic glass-ceramic composition (HASi) over titanium substrate using dense HASi target. Bioactive glass compositions are considered the most useful synthetic materials for immediate bone attachment because of its bioresorption, osteoconduction and osteointegration characteristics under in vivo conditions. The disadvantage of its brittleness associated with bioactive glass-ceramics has prompted its coating over metallic implants for the combination of duo mechanical and bioactive properties.

Novel nanoporous bioceramic spheres for drug delivery application: a preliminary in vitro investigation.

Background: Bioceramics and their composites have found myriad applications in medicine as superlative osteoalloplasts. Their potential to function as a biocompatible resorbable drug delivery system is being explored. The present study is a preliminary investigation into the efficacy of these indigenously developed nanoporous materials as vehicles for therapeutic agents.

Adipogenesis on biphasic calcium phosphate using rat adipose-derived mesenchymal stem cells: in vitro and in vivo.

Developing adipose tissue-engineered construct to mend soft tissue defects arising from traumatic injury, tumor resections, and maxillofacial abnormalities is of prime importance in plastic and reconstructive surgical procedures. It is apparent that the clinical outcome of classic techniques like adipose tissue transplantation is unpredictable, with graft resorption, lack of vascularization, and impaired functionality. In this prospective, the concept of tissue engineering was adopted to fabricate a combination product with biphasic calcium phosphate (BCP) and rat adipose-derived mesenchymal stem cells (ASCs) toward the development of an adipose tissue construct.

Preparation and analysis of chemically gradient functional bioceramic coating formed by pulsed laser deposition.

Bioactive ceramic coatings based on calcium phosphates yield better functionality in the human body for a variety of metallic implant devices including orthopaedic and dental prostheses. In the present study chemically and hence functionally gradient bioceramic coating was obtained by pulsed laser deposition method. Calcium phosphate bioactive ceramic coatings based on hydroxyapatite (HA) and tricalcium phosphate (TCP) were deposited over titanium substrate to produce gradation in physico-chemical characteristics and in vitro dissolution behaviour.

Laser surface modification of titanium substrate for pulsed laser deposition of highly adherent hydroxyapatite.

Biomedical implant devices made out of titanium and its alloys are benefited by a modified surface or a bioactive coating to enhance bone bonding ability and to function effectively in vivo for the intended period of time. In this respect hydroxyapatite coating developed through pulsed laser deposition is a promising approach. Since the success of the bioactive ceramic coated implant depends mainly on the substrate-coating strength; an attempt has been made to produce micro patterned surface structure on titanium substrate for adherent hydroxyapatite coating.

Pulsed laser deposition of hydroxyapatite on titanium substrate with titania interlayer.

Pulsed laser deposition (PLD) has been used to deposit hydroxyapatite (HA) ceramic over titanium substrate with an interlayer of titania. PLD has been identified as a potential candidate for bioceramic coatings over metallic substrates to be used as orthopedic and dental implants because of better process control and preservation of phase identity of the coating component. However, direct deposition of hydroxyapatite on titanium at elevated temperature results in the formation of natural oxide layer along with some perovskites like calcium titanate at the interface.

Nano iron oxide-hydroxyapatite composite ceramics with enhanced radiopacity.

Hydroxyapatite has been widely used for a variety of bone filling and augmentation applications. But the poorly resolved X-ray image of certain hydroxyapatite (HA) based implants such as porous blocks and self setting HA cements is a radiological problem to surgeons for monitoring of the implant and early diagnosis complications. In the present work the practical difficulty related to the reduced X-ray opacity was overcome by exploiting the contrast enhancement property of iron oxide nano particles.

Treatment of goat femur segmental defects with silica-coated hydroxyapatite--one-year follow-up.

Segmental bone defects caused by tumor resections, trauma, and skeletal abnormalities such as osteomyelitis remain a major problem in orthopedics because of the lack of predictability in attaining functional bone after the treatment. The objective of this study was to propose an indigenous porous biodegradable triphasic ceramic (calcium silicate, tricalcium phosphate, and hydroxyapatite [HA])-coated HA (core) (HASi) for the repair of such segmental defects. With respect to the synthesis of HASi, HA blocks were prepared by wet precipitation, dipped in silica sol (sol gel method), sintered at 1200 degrees C, polished in the form of hollow cylinder (2 cm long with an outer and inner diameter of 2 cm and 7 mm, respectively), and implanted into a 2-cm segmental defect created in the goat femur diaphysis.

Surface-phosphorylated copolymer promotes direct bone bonding.

The bone bonding potential of surface-phosphorylated poly (2-hydroxyethyl methacrylate-co-methyl methacrylate) [poly (HEMA-co-MMA)] has been investigated and compared with commercially available poly (methyl methacrylate) bone cement (CMW1 radiopaque, Depuy; Johnson & Johnson, Blackpool, Lancashire, England, United Kingdom) as control. Poly (HEMA-co-MMA) is synthesized by free radical-initiated copolymerization and surface functionalized by phosphorylation. The X-ray photoelectron spectroscopy confirms the presence of surface-bound phosphate groups on poly (HEMA-co-MMA).