Improvement of osteogenic differentiation potential of placenta-derived mesenchymal stem cells by metformin via AMPK pathway activation.

Background: Placenta-derived human mesenchymal stem cells (PL-MSCs) have gained a lot of attention in the field of regenerative medicine due to their availability and bone-forming capacity. However, the osteogenic differentiation capacity of these cells remains inconsistent and could be improved to achieve greater efficiency. Although metformin, a widely used oral hypoglycemic agent, has been shown to increase bone formation in various cell types, its effect on osteogenic differentiation of PL-MSCs has not yet been investigated.

Comparison between local-made and imported porous polyethylene orbital implant: a randomized controlled equivalence trial and multicenter study.

Aim: To compare the exposure rate, infection rate, percentage of enhancement, and success rate between Medpor and the three-dimensional printed polyethylene (3DP-PE) orbital implant in a preliminary report.

Methods: This prospective, randomized, equivalence, controlled trial was conducted at two institutes. The equivalent margin was ±10%.

Process Development for Fabricating 3D-Printed Polycaprolactone-Infiltrated Hydroxyapatite Bone Graft Granules: Effects of Infiltrated Solution Concentration and Agitating Liquid.

Bone grafts are commonly used in orthopedic and dental surgeries to facilitate bone repair and regeneration. A new type of bone graft, polycaprolactone-infiltrated three dimensionally printed hydroxyapatite (3DP HA/PCL), was previously developed by infiltrating polycaprolactone (PCL) into preformed three-dimensional-printed hydroxyapatite (3DP HA) that was fabricated using binder jetting technology combined with a low-temperature phase transformation process. However, when producing small granules, which are often used for bone grafting, issues of granule agglomeration emerged, complicating the application of this method.

Efficacy and Safety of Antibiotic Impregnated Microporous Nanohydroxyapatite Beads for Chronic Osteomyelitis Treatment: A Multicenter, Open-Label, Prospective Cohort Study.

Chronic osteomyelitis is still a serious health problem that causes disabling conditions and has an impact on the quality of life. The objective of this study was to determine the clinical efficacy and safety of localized antibiotics delivery via impregnated microporous nanohydroxyapatite (nHA-ATB) beads for chronic osteomyelitis treatment. A total of 62 patients were enrolled in this study.

Polycaprolactone versus collagen membrane and 1-year clinical outcomes: A randomized controlled trial.

Background: Polycaprolactone (PCL) is a synthetic aliphatic polyester widely used in biomedical applications with biodegradability in the body and promotes cell proliferation and differentiation. A newly developed bilayered PCL membrane was developed for possibly being used as a membrane in guided bone regeneration (GBR).

Purpose: To compare the clinical efficacy between a newly developed bilayered PCL membrane with a Cytoplast™ RTM collagen membrane for GBR with simultaneous implant placement.

Osteogenic differentiation and proliferation potentials of human bone marrow and umbilical cord-derived mesenchymal stem cells on the 3D-printed hydroxyapatite scaffolds.

Mesenchymal stem cells (MSCs) are a promising candidate for bone repair. However, the maintenance of MSCs injected into the bone injury site remains inefficient. A potential approach is to develop a bone-liked platform that incorporates MSCs into a biocompatible 3D scaffold to facilitate bone grafting into the desired location.

Cefazolin Loaded Oxidized Regenerated Cellulose/Polycaprolactone Bilayered Composite for Use as Potential Antibacterial Dural Substitute.

Oxidized regenerated cellulose/polycaprolactone bilayered composite (ORC/PCL bilayered composite) was investigated for use as an antibacterial dural substitute. Cefazolin at the concentrations of 25, 50, 75 and 100 mg/mL was loaded in the ORC/PCL bilayered composite. Microstructure, density, thickness, tensile properties, cefazolin loading content, cefazolin releasing profile and antibacterial activity against were measured.

Customized 3D printed nanohydroxyapatite bone block grafts for implant sites: A case series.

Patients: A case series of 12 patients (mean age, 53.5 years) with horizontal ridge deficiencies had augmentations with customized 3D printed nanohydroxyapatite (3DHA) block grafts prior to implant placement. 3DHA graft materials were fabricated to fit the individual patient defects using DICOMs from CBCT images obtained from each patient.

Clinical evaluation of 3D printed nano-porous hydroxyapatite bone graft for alveolar ridge preservation: A randomized controlled trial.

Background/purpose: Ridge resorption after tooth extraction may result in inadequate bone volume and unfavorable ridge architecture for ideal implant placement. The use of bone substitutes has been advocated to fill extraction sites and to enhance primary implant stability. This study was made to evaluate the clinical efficacy of novel 3D printed nano-porous hydroxyapatite (3DP HA, test group) in comparison to nano-crystalline bone graft (NanoBone®, control group) in alveolar ridge preservation prior to implant placement.

In vitro resorbability and granular characteristics of 3D-printed hydroxyapatite granules versus allograft, xenograft, and alloplast for alveolar cleft surgery applications.

Three-dimensionally printed hydroxyapatite (3DP HA) was investigated in regards to its functional properties supporting bone regeneration and tooth movement in alveolar cleft applications. Commercially available bovine xenograft (BXG), biphasic calcium phosphate alloplast (BCP), and two types of freeze-dried bone allograft granules (FDBA and FDBA-CMC) were employed as control samples. Degradability was studied by submerging the samples in pH 7.

Effectiveness of bilayer porous polyethylene membrane for alveolar ridge preservation: A randomized controlled trial.

Background: Porous polyethylene has been successfully used in several medical applications with good outcomes. Based on this, a new bilayer porous polyethylene membrane (B-PPM) was developed for possibly being used as a membrane in alveolar ridge preservation.

Purpose: To evaluate the clinical efficacy of a new B-PPM in comparison to high-density polytetrafluoroethylene membrane (d-PTFE) in alveolar ridge preservation.

evaluation of bilayer ORC/PCL composites in a rabbit model for using as a dural substitute.

Objective: After a neurosurgical procedure, dural closure is commonly needed to prevent cerebrospinal fluids (CSF) leakage and to reduce the risk of complications, including infections and chronic inflammatory reactions. Although several dural substitutes have been developed, their manufacturing processes are complicated and costly and that many of them have been implicated in causing postoperative complications. This study aimed to assess the effectiveness and safety of new bilayer ORC/PCL composites in a rabbit model.

Clinical and histological evaluations of alveolar ridge augmentation using a novel bi-layered porous polyethylene barrier membrane.

Guided bone regeneration (GBR) is an effective alveolar ridge reconstruction technique used before or at implant placement. The combination of various barrier membranes and bone substitutes has been employed. This study aimed to perform a preliminarily evaluation of the safety and performance of a new nonabsorbable bi-layered porous polyethylene (PPE) membrane, in combination with a freeze-dried cortical bone allograft in posterior mandibular ridge augmentation.

Performance evaluation of bilayer oxidized regenerated cellulose/poly ε-caprolactone knitted fabric-reinforced composites for dural substitution.

Ideally, alloplastic dural substitute should have functional properties resembling human dura mater and retain a watertight closure to prevent cerebrospinal leakage. Therefore, functional properties for successful dural closure application of newly developed bilayer oxidized regenerated cellulose knitted fabric/poly ε-caprolactone knitted fabric-reinforced composites were studied and compared with human cadaveric dura mater and three commercial dural substitutes including two collagen matrices and one synthetic poly-L-lactide patch. It was found that oxidized regenerated cellulose knitted fabric/poly ε-caprolactone knitted fabric-reinforced composites uniquely contained a bilayer structure consisting of micropores distributed within the relatively dense microstructure.

Evaluation of tissue ingrowth and reaction of a porous polyethylene block as an onlay bone graft in rabbit posterior mandible.

Purpose: A new form of porous polyethylene, characterized by higher porosity and pore interconnectivity, was developed for use as a tissue-integrated implant. This study evaluated the effectiveness of porous polyethylene blocks used as an onlay bone graft in rabbit mandible in terms of tissue reaction, bone ingrowth, fibrovascularization, and graft-bone interfacial integrity.

Methods: Twelve New Zealand white rabbits were randomized into 3 treatment groups according to the study period (4, 12, or 24 weeks).

Enhancement of mechanical properties of 3D printed hydroxyapatite by combined low and high molecular weight polycaprolactone sequential infiltration.

A new infiltration technique using a combination of low and high molecular weight polycaprolactone (PCL) in sequence was developed as a mean to improve the mechanical properties of three dimensional printed hydroxyapatite (HA). It was observed that using either high (M ~80,000) or low (M ~10,000) molecular weight infiltration could only increase the flexural modulus compared to non-infiltrated HA, but did not affect strength, strain at break and energy at break. In contrast, a combination of low and high molecular infiltration in sequence increased the flexural modulus, strength and energy at break compared to those of non-infiltrated HA or infiltrated by high or low molecular weight PCL alone.

Bilayer oxidized regenerated cellulose/poly ε-caprolactone knitted fabric-reinforced composite for use as an artificial dural substitute.

A novel bilayer knitted fabric-reinforced composite for potentially being used as a dural substitute was developed by solution infiltration of oxidized regenerated cellulose knitted fabric (ORC) with poly ε-caprolactone (PCL) solution at various concentrations ranging 10-40 g/100 mL. It was found that the density of all formulations did not differ significantly and was lower than that of the human dura. Microstructure of the samples typically comprised a bilayer structure having a nonporous PCL layer on one side and the ORC/PCL composite layer on another side.

Influence of process parameters on the content of biomimetic calcium phosphate coating on titanium: a Taguchi analysis.

In this study, a statistical design of experimental methodology based on Taguchi orthogonal design has been used to study the effect of various processing parameters on the amount of calcium phosphate coating produced by such technique. Seven control factors with three levels each including sodium hydroxide concentration, pretreatment temperature, pretreatment time, cleaning method, coating time, coating temperature and surface area to solution volume ratio were studied. X-ray diffraction revealed that all the coatings consisted of the mixture of octacalcium phosphate (OCP) and hydroxyapatite (HA) and the presence of each phase depended on the process conditions used.

Preparation and characterization of nanosized silver phosphate loaded hydroxyapatite by single step co-conversion process.

The preparation and characterization of silver phosphate nanoparticles loaded hydroxyapatite aiming to enhance the bactericidal performance by a single step co-conversion technique using low temperature phosphorization in the presence of various silver nitrate concentration (AgNO, ranging 0.001-0.1M) was performed.

Fit-and-fill analysis of trochanteric gamma nail for the Thai proximal femur: a virtual simulation study.

The present study present a three-dimensional virtual simulation method to evaluate the fit-and-fill effect of the insertion of a trochanteric gamma nail (TGN) in 98 Thai dadaveric proximal femora. The circular best fit of the 2-dimensional cross-section of the femoral canal and the nail at 4 levels [d100, d120, d140 and d160] which were located at 100, 120, 140 and 160 mm distal to the tip of the greater trochanter were calculated. The evaluation of each level included, 1) the diameters of the medullary canal, 2) the percentage of area filled by the nail in the unreamed medullary canal, 3) the minimal reamer diameter that required enlargement of the canal to accommodate TGN insertion, 4) the minimal inner cortical reaming thickness that needed to be removed, 5) the percentage of cortical bone area that needed to be removed prior to nail insertion and 6) the deviation of the nail center from the center of the medullary canal.