Transplantation of Mature Adipocyte-Derived Dedifferentiated Fat Cells Facilitates Periodontal Tissue Regeneration of Class II Furcation Defects in Miniature Pigs.

Adipose tissue is composed mostly of adipocytes that are in contact with capillaries. By using a ceiling culture method based on buoyancy, lipid-free fibroblast-like cells, also known as dedifferentiated fat (DFAT) cells, can be separated from mature adipocytes with a large single lipid droplet. DFAT cells can re-establish their active proliferation ability and transdifferentiate into various cell types under appropriate culture conditions.

Compromised Epithelial Cell Attachment after Polishing Titanium Surface and Its Restoration by UV Treatment.

Titanium-based implant abutments and tissue bars are polished during the finalization. We hypothesized that polishing degrades the bioactivity of titanium, and, if this is the case, photofunctionalization-grade UV treatment can alleviate the adverse effect. Three groups of titanium disks were prepared; machined surface, polished surface and polished surface followed by UV treatment (polished/UV surface).

Ultraviolet treatment restores bioactivity of titanium mesh plate degraded by contact with medical gloves.

Titanium mesh plate (Ti mesh) used for bone augmentation inadvertently comes into contact with medical gloves during trimming and bending. We tested the hypotheses that glove contact degrades the biological capability of Ti mesh and that ultraviolet treatment (UV) can restore this capability. Three groups of Ti mesh specimens were prepared: as-received (AR), after glove contact (GC), and after glove contact followed by UV treatment.

Mouthguards and their use in sports: Report of the 1st International Sports Dentistry Workshop, 2016.

There appears to be much confusion or misinformation worldwide regarding mouthguards and their use in sports. In an effort to clarify where the international dental community stands on mouthguards and mouthguard research, the workshop looked at some important questions. The goal was to one day formulate consensus statements related to these questions, which will be based on current scientific evidence-based research, to motivate the international community of the importance of dentally fitted laminated mouthguards and the wearing of them by athletes of all sports.

Novel antioxidant capability of titanium induced by UV light treatment.

The intracellular production of reactive oxygen species (ROS) is a representative form of cellular oxidative stress and plays an important role in triggering adverse cellular events, such as the inflammatory reaction and delayed or compromised differentiation. Osteoblastic reaction to titanium with particular focus on ROS production remains unknown. Ultraviolet (UV) light treatment improves the physicochemical properties of titanium, specifically the induction of super hydrophilicity and removal of hydrocarbon, and eventually enhances its osteoconductivity.

Effect of UV Photofunctionalization on Osseointegration in Aged Rats.

Objectives: This study evaluated the effect of photofunctionalization on osseointegration under the biologically adverse conditions of aging.

Materials: First of all, bone marrow-derived osteoblastic cells from young (8 weeks old) and aged (15 months old) rats were biologically characterized. Then, the osteoblasts from aged rats were seeded on titanium discs with and without photofunctionalization, and assessed for initial cell attachment and osteoblastic functions.

Use of Rat Mature Adipocyte-Derived Dedifferentiated Fat Cells as a Cell Source for Periodontal Tissue Regeneration.

Lipid-free fibroblast-like cells, known as dedifferentiated fat (DFAT) cells, can be generated from mature adipocytes with a large single lipid droplet. DFAT cells can re-establish their active proliferation ability and can transdifferentiate into various cell types under appropriate culture conditions. The first objective of this study was to compare the multilineage differentiation potential of DFAT cells with that of adipose-derived stem cells (ASCs) on mesenchymal stem cells.

Bone Generation Profiling Around Photofunctionalized Titanium Mesh.

Purpose: The aim of this study was to evaluate whether photofunctionalization of titanium mesh enhances its osteoconductive capability.

Materials And Methods: The titanium mesh (0.2 mm thickness) used in this study was made of commercially pure grade-2 titanium and had hexagonal apertures (2 mm width).

Enhancing osteoblast-affinity of titanium scaffolds for bone engineering by use of ultraviolet light treatment.

Ultraviolet (UV) treatment immediately prior to use is attracting attention as an effective surface conditioning method for titanium to improve osteoblast-affinity. The affinity of titanium to osteoblasts in two-dimensional plate culture has been well studied, but that in three-dimensional cultures remains unclear. Here, we examined the effect of UV treatment on titanium scaffolds, comprising micro-thin titanium fibers, used in bone engineering.

Osteogenic cell sheets reinforced with photofunctionalized micro-thin titanium.

Cell sheet technology has been used to deliver cells in single-sheet form with an intact extracellular matrix for soft tissue repair and regeneration. Here, we hypothesized that titanium-reinforced cell sheets could be constructed for bone tissue engineering and regeneration. Fifty-µm-thick titanium plates containing apertures were prepared and roughened by acid etching, some of which were photofunctionalized with 12 min of UV light treatment.

Periodontal tissue regeneration by transplantation of rat adipose-derived stromal cells in combination with PLGA-based solid scaffolds.

Regeneration of damaged periodontium is challenging due to its multi-tissue composition. Mesenchymalstem cell-based approaches using adipose-derived stromal cells (ASCs) may contribute to periodontal reconstruction, particularly when combined with the use of scaffolds to maintain a space for new tissue growth. The aim of this study was to assess the regenerative potential of ASCs derived from inbred or outbred rats in combination with novel solid scaffolds composed of PLGA (Poly D,L-lactic-co-glycolic acid) (PLGA-scaffolds).

N-acetyl cysteine as an osteogenesis-enhancing molecule for bone regeneration.

Bone regeneration often requires cues from osteogenesis-inducing factors for successful outcome. N-acetyl cysteine (NAC), an anti-oxidant small molecule, possibly modulates osteoblastic differentiation. This study investigated the potential of NAC as an osteogenesis-enhancing molecule in vitro and in vivo.

Bone integration capability of nanopolymorphic crystalline hydroxyapatite coated on titanium implants.

The mechanism by which hydroxyapatite (HA)-coated titanium promotes bone-implant integration is largely unknown. Furthermore, refining the fabrication of nano-structured HA to the level applicable to the mass production process for titanium implants is challenging. This study reports successful creation of nanopolymorphic crystalline HA on microroughened titanium surfaces using a combination of flame spray and low-temperature calcination and tests its biological capability to enhance bone-implant integration.

Bone integration capability of alkali- and heat-treated nanobimorphic Ti-15Mo-5Zr-3Al.

The role of nanofeatured titanium surfaces in a number of aspects of in vivo bone-implant integration, and, in particular, their potential advantages over microfeatured titanium surfaces, as well as their specific contribution to osteoconductivity, is largely unknown. This study reports the creation of a unique nanobimorphic titanium surface comprised of nanotrabecular and nanotuft-like structures and determines how the addition of this nanofeature to a microroughened surface affects bone-implant integration. Machined surfaces without microroughness, sandblasted microroughened surfaces, and micro-nano hybrid surfaces created by sandblasting and alkali and heat treatment of Ti-15Mo-5Zr-3Al alloy were subjected to biomechanical, interfacial and histological analyses in a rat model.

TiO2 micro-nano-hybrid surface to alleviate biological aging of UV-photofunctionalized titanium.

Bioactivity and osteoconductivity of titanium degrade over time after surface processing. This time-dependent degradation is substantial and defined as the biological aging of titanium. UV treatment has shown to reactivate the aged surfaces, a process known as photofunctionalization.

Enhanced bone-integration capability of alkali- and heat-treated nanopolymorphic titanium in micro-to-nanoscale hierarchy.

This study introduces nanopolymorphic features of alkali- and heat-treated titanium surfaces, comprising of tuft-like, plate-like, and nodular structures that are smaller than 100 nm and determines whether and how the addition of these nanofeatures to a microroughened titanium surface affects bone-implant integration. A comprehensive assessment of biomechanical, interfacial, and histological analyses in a rat model was performed for machined surfaces without microroughness, sandblasted-microroughened surfaces, and micro-nano hybrid surfaces created by sandblasting and alkali and heat treatment. The microroughened surface accelerated the establishment of implant biomechanical fixation at the early healing stage compared with the non-microroughened surface but did not increase the implant fixation at the late healing stage.

Effects of UV photofunctionalization on the nanotopography enhanced initial bioactivity of titanium.

This study addresses the control of the biological capabilities of titanium through specific nanosurface features and its potential modulation by UV photofunctionalization. Rat bone marrow derived osteoblasts were cultured on titanium disks with micropits alone, micropits with 100 nm nodules, micropits with 300 nm nodules, or micropits with 500 nm nodules, with or without UV treatment. After a 24 h incubation protein adsorption, as well as the attachment, retention, and spread of osteoblasts were examined in correlation with the topographical parameters of the titanium substrates.

Synergistic effects of UV photofunctionalization and micro-nano hybrid topography on the biological properties of titanium.

Titanium surfaces with micro-nano hybrid topography (nanoscale nodules in microscale pits) have been recently demonstrated to show higher biological capability than those with microtopography alone. On the other hand, UV treatment of titanium surfaces, which is called UV photofunctionalization, has recently been introduced to substantially increase the biological capability and osteoconductivity of titanium surfaces. However, synergistic effects of these two advanced surface modification technologies and regulatory factors to potentially modulate the mutual effects have never been addressed.

Selective cell affinity of biomimetic micro-nano-hybrid structured TiO2 overcomes the biological dilemma of osteoblasts.

Objective: There is a great demand for dental implant surfaces to accelerate the process of peri-implant bone generation to reduce its healing time and enable early loading. To this end, an inverse correlation between the proliferation and functional maturation (differentiation) in osteoblasts presents a challenge for the rapid generation of greater amounts of bone. For instance, osteoblasts exhibit faster differentiation but slower proliferation on micro-roughened titanium surfaces.

Cellular behavior on TiO2 nanonodular structures in a micro-to-nanoscale hierarchy model.

Biological tissues involve hierarchical organizations of structures and components. We created a micropit-and-nanonodule hybrid topography of TiO(2) by applying a recently reported nanonodular self-assembly technique on acid-etch-created micropit titanium surfaces. The size of the nanonodules was controllable by changing the assembly time.

Ultraviolet light-mediated photofunctionalization of titanium to promote human mesenchymal stem cell migration, attachment, proliferation and differentiation.

Improving the osteoconductive potential of titanium implants has been of continuing interest in the fields of dentistry and orthopedic surgery. This study determined the bioactivity of ultraviolet (UV) light-treated titanium. Human mesenchymal stem cells (MSCs) were cultured on acid-etched microtopographical titanium surfaces with and without 48h pretreatment with UVA (peak wavelength of 360n m) or UVC (peak wavelength of 250 nm).

N-acetyl cysteine (NAC)-mediated detoxification and functionalization of poly(methyl methacrylate) bone cement.

Currently used poly(methyl methacrylate) (PMMA)-based bone cement lacks osteoconductivity and induces osteolysis and implant loosening due to its cellular and tissue-toxicity. A high percentage of revision surgery following the use of bone cement has become a significant universal problem. This study determined whether incorporation of the amino acid derivative N-acetyl cysteine (NAC) in bone cement reduces its cytotoxicity and adds osteoconductivity to the material.

N-acetyl cysteine prevents polymethyl methacrylate bone cement extract-induced cell death and functional suppression of rat primary osteoblasts.

This study examines the cytotoxicity of bone cement extract to osteoblasts and the potential detoxification and restoration of osteoblastic function by an antioxidant amino acid, N-acetyl cysteine (NAC). The osteoblastic cells derived from rat femurs were cultured with extract from polymethyl methacrylate (PMMA)-based bone cement. The calcein and ethidium homodimer staining of the cells after 24-h incubation showed that 23.

Microtopography of titanium suppresses osteoblastic differentiation but enhances chondroblastic differentiation of rat femoral periosteum-derived cells.

Despite the clinical fact that endosseous titanium implants directly contacts periosteum, the behavior and response of the periosteum-derived cells to surface topography of titanium have rarely been studied. This study examines the effect of titanium surface microtopography on osteoblastic and possibly-modulated chondroblastic phenotypes of femoral periosteum-derived cells. Rat femoral periosteum-derived cells were cultured on either relatively smooth, machined titanium surface or acid-etched, micro-roughened titanium surface.

Effect of supramicron roughness characteristics produced by 1- and 2-step acid etching on the osseointegration capability of titanium.

Purpose: The purpose of this study was to compare the osteoblastic and osteogenic responses to titanium surfaces roughened by 1-step and 2-step acid etching.

Materials And Methods: Titanium surfaces created by 1-step (AE1) and 2-step (AE2) acid-etching processes were analyzed using scanning electron microscopy (SEM), atomic force microscopy (AFM), and an optical interferometry (OI). Rat bone marrow-derived osteoblastic cells were cultured on these 2 surfaces.