Reduced skin lipid content in obese Japanese women mediated by decreased expression of rate-limiting lipogenic enzymes.

Skin barrier function is often deficient in obese individuals, but the underlying molecular mechanisms remain unclear. This study investigated how skin structure and lipid metabolism, factors strongly associated with barrier function, differed among 50 Japanese women of greatly varying body mass index (BMI). Subjects receiving breast reconstruction surgery were chosen for analysis to obtain skin samples from the same site.

Development of a novel dental resin cement incorporating FGF-2-loaded polymer particles with the ability to promote tissue regeneration.

Objective: Aiming to achieve bioactive dental resins that promote healing of surrounding tissues, we developed novel poly(2-hydroxyethyl methacrylate/trimethylolpropane trimethacrylate) (polyHEMA/TMPT) particles. These particles have been reported to be useful as a non-biodegradable carrier for fibroblast growth factor-2 (FGF-2) in vitro. The aim of this study was to evaluate the ability of an adhesive resin incorporating FGF-2-loaded polymer particles to promote tissue regeneration in vitro and in vivo.

Immunohistochemical analysis of dentin matrix protein 1 (Dmp1) phosphorylation by Fam20C in bone: implications for the induction of biomineralization.

Dmp1 is an acidic phosphoprotein that is specifically expressed in osteocytes. During the secretory process, the full-length, precursor Dmp1 is cleaved into N- and C-terminal fragments. C-terminal Dmp1 is phosphorylated, becoming a highly negatively charged domain that may assist in bone mineralization by recruiting calcium ions and influencing subsequent mineral deposition.

Influence of Nonenzymatic Glycation in Dentinal Collagen on Dental Caries.

Advanced glycation end-products (AGEs) are generated via nonenzymatic glycation of dentinal collagen, resulting in accumulation of AGEs in dentin tissue. Since accumulated AGEs cause crosslinking between amino acid polypeptides in the collagen molecule and modify mechanical properties of dentinal collagen, the authors assumed that there would be a significant interaction between the generation of AGEs and progression of caries in dentin. To confirm such an interaction, spectroscopic imaging analyses (i.

Bonding effectiveness and multi-interfacial characterization of two direct buildup resin core systems bonded to post-space dentin.

Objectives: The aim of the present study was to evaluate the bonding effectiveness of two resin core buildup systems using conventional methods in the field of adhesive dentistry and a new non-destructive method.

Materials And Methods: Twenty-four single-rooted human teeth were built up with dual-cure one-step self-etch adhesive and composite systems (SY1: Clearfil DC bond and Clearfil DC core automix, SY2: Clearfil bond SE one and Clearfil DC core automix one). The prepared samples were sectioned into approximately 1 × 1-mm-thick beams and subjected to micro-tensile bond strength (μTBS) testing (n = 24).

Bonding effectiveness of self-adhesive and conventional-type adhesive resin cements to CAD/CAM resin blocks. Part 2: Effect of ultrasonic and acid cleaning.

The present study assessed the effect of ultrasonic and acid cleaning on resin cement bonding to CAD/CAM resin blocks. One of two resin cements, PANAVIA V5 (PV5) or PANAVIA SA CEMENT HANDMIX (PSA), were bonded to one of 24 CAD/CAM blocks (KATANA AVENCIA BLOCK). Each cement group was divided into four subgroups: no cleaning (Ctl), ultrasonic cleaning (Uc), acid cleaning (Ac) and Uc+Ac.

Bonding effectiveness of self-adhesive and conventional-type adhesive resin cements to CAD/CAM resin blocks. Part 1: Effects of sandblasting and silanization.

The present study assessed the effect of sandblasting and silanization on resin cement bond strengths to CAD/CAM resin blocks. Twenty four blocks (KATANA AVENCIA BLOCK) were divided into two resin cement groups (PANAVIA V5 [PV5] and PANAVIA SA CEMENT HANDMIX [PSA]), and further divided into four subgroups representing different surface treatment methods: no treatment (Ctl), silanization (Si), sandblasting (Sb), and Sb+Si. After resin application, microtensile bond strengths (μTBSs) were measured immediately, 1, 3 and 6 months after water storage.

Decrease in fluorescence lifetime by glycation of collagen and its application in determining advanced glycation end-products in human dentin.

Advanced Glycation End-products (AGEs) are produced by the Maillard reaction, which causes cross-linking of collagen and results in changes in the mechanical properties of collagen tissues. Several types of AGE fluoresce, and measurement of this fluorescence is effective for determining the presence of AGEs. Because fluorescence intensity by steady-state fluorometry is affected by sample surface condition and light source, we focused on fluorescence lifetime measurement (FLM).

Accumulation of advanced glycation end-products in human dentine.

Cross-linking of collagen by Advanced Glycation End-products (AGEs) occurs by non-enzymatic glycation (Maillard reaction). The purpose of this study was to examine whether AGEs are formed in human dentinal collagen, and to consider any possible influence of AGEs on dentinal physiology. Mechanical characteristics, fluorescence spectra and immunohistochemical analyses of demineralized dentine sections from young subjects were compared with those of aged ones.

Structural modifications of dentinal microcracks with human aging.

Several studies have reported the mechanism of crack propagation with aging. Although structural modifications of dentinal microcracks with aging have been evaluated by observing the cracked surface using scanning electron microscope (SEM), very few attempts have been made at sectional observation of the microcracks inside dentine using transmission electron microscopy (TEM). The objectives of this study were to: (1) examine the process of dentinal microcrack formation using TEM and (2) to morphologically evaluate the relation between dentinal microcrack propagation and human aging.

Mechanical and morphological evaluation of the bond-dentin interface in direct resin core build-up method.

Objectives: The purpose of this study was to evaluate the interfacial adhesion between resin and root canal dentin in the direct resin core build-up method in terms of microtensile bond strength (μTBS) and dentin micro morphology.

Methods: Single-rooted human teeth were decoronated at the cementoenamel junction and endodontically treated. Post spaces were prepared in the roots to a depth of 10mm.

Detection of dentinal microcracks using infrared thermography.

Introduction: It is difficult to make a definite diagnosis of a cracked tooth solely based on an inspection within the root canal, especially in case of microcracks. At present, there seems to be no established method to detect dentinal microcracks in roots; therefore, the current detection techniques need to be improved. Vibrothermography (VibroIR) helps to detect microcracks by the friction heat generated from ultrasonic vibration.

Ultra-structural observation of human enamel and dentin by ultra-high-voltage electron tomography and the focus ion beam technique.

Human enamel and dentin are hard and brittle mineralized tissues. It is difficult to prepare thin specimens (under 200 nm) of these tissues for transmission electron microscope observation without demineralizing them. We present a novel method of creating three-dimensional ultra-structural images of human enamel and dentin, using the focus ion beam (FIB) method and ultra-high-voltage electron microscope tomography.

Virtual reality simulation training for dental surgery.

In dentistry the exquisite hand skill is required for daily treatments, However, dental students have little chance to treat patients in the clinical training So, present study constructed a process simulation to train the hand skill for tooth extraction, especially impacted wisdom tooth that was an example of the difficult case by using virtual reality haptic device.

Dental haptic simulator to train hand skill of student - calibration method to realize visual haptic environment.

In prior work, we have developed dental training simulator to train hand skill of student (HHDTS). In the present study, we performed calibration between haptic device coordinate system and half-mirror coordinate system for our system to realize real clinical situation. As a result, the user can overlay the CG (turbine) onto the stylus of haptic device and intract to the CG (tooth) directly.

Relationship between the color of carious dentin with varying lesion activity, and bacterial detection.

Objectives: To investigate the relationship between the color of carious dentin with varying lesion activity, and bacterial detection in the lesions.

Methods: In 26 extracted human molars with coronal dentin caries and four extracted sound human molars, dentin was removed by a round bur every 150 microm from the dentin surface, in the direction of the pulp chamber. Before and after removal, images of nine-color samples and the dentin surface stained with a caries detector dye (1% acid red in propylene glycol) were taken simultaneously by a charge-coupled device (CCD), and dentinal tissue samples were taken with a new round bur.

Evaluating the objectivity of caries removal with a caries detector dye using color evaluation and PCR.

Objectives: This laboratory study evaluated the objectivity of caries removal with a caries detector dye by color and bacterial evaluations.

Methods: In 41 cases of dentin caries (32 extracted human molars), carious tissues were removed using a caries detector dye. Images of dentin surfaces with color-matching stickers were acquired using a CCD camera, and dentinal tissue samples were collected with new round burs.

Fatigue of tooth-colored restoratives in aqueous environment.

The purpose of this study was to investigate the interaction between mechanical and chemical fatigue in resin composites and dental ceramics, and the effects thereof on fatigue resistance of tooth-colored restoratives. To this end, the fatigue fracture resistance of restoratives under dry and aqueous conditions were analyzed by a dynamic fatigue crack propagation test using beam-shaped specimens with a precrack. Fatigue crack propagation characteristics were expressed by the correlation between fatigue crack growth rate (da/dN) and stress intensity factor range (deltaK).

Relationship between colors of carious dentin and laser fluorescence evaluations in caries diagnosis.

This in vitro study investigated the relationship between assessments of dentin caries using a laser fluorescence device (DIAGNOdent) and a caries detector dye during caries removal. The dentin of eight extracted carious molars was removed at 300-microm interval points from the dentin surface toward the pulp chamber. Before and after each removal, images of the carious surfaces were taken in association with color-matching stickers (for color correction) and the surfaces were evaluated by DIAGNOdent based on fluorescence emission from the tooth surface.

The accuracy of electrical method for microleakage evaluation by a three-dimensional analysis.

Objectives: This in vitro study aimed to investigate the accuracy of an electrical method for the evaluation of microleakage by a three-dimensional analysis of dye penetration.

Methods: Coronal cavities were prepared on buccal, palatal or lingual surfaces in extracted human molars. The cavities were then filled with resin composites and were subjected to 10,000 load cycles (425g).

Fatigue behavior of resin composites in aqueous environments.

Objectives: Interaction between mechanical and chemical fatigue of resin composites was investigated.

Methods: Fatigue fracture resistance of composites after (1) water immersion and under (2) dry and (3) aqueous conditions was analyzed using a fatigue crack propagation test. The characteristics of fatigue crack propagation were expressed as the correlation between the fatigue crack growth rate (da/dN) and stress intensity factor range (DeltaK) and by the fatigue crack growth threshold (DeltaKth).

Three-dimensional evaluation of gap formation of cervical restorations.

Objectives: In some studies gap formation has been evaluated in just one section of the restorative. This in vitro study aimed to design a quantitative three-dimensional method for evaluation of the contraction gap in restoratives.

Methods: Cervical cavities were prepared on buccal, palatal or lingual surfaces in human extracted molars and were then filled with resin composites.

Optimal positioning for a dental operating microscope during nonsurgical endodontics.

The most comfortable positioning for a dental operating microscope (DOM) during nonsurgical endodontics for operators was investigated. Operators were categorized into 3 groups according to height. We recorded the time taken to obtain magnified images, and the angles of binoculars, microscope body, and the mirror to floor surfaces.

Relationship between bacterial infection and evaluation using a laser fluorescence device, DIAGNOdent.

The aim of this in vitro study was to investigate the relationship between bacterial infections in carious dentin when detected by two different methods -- polymerase chain reaction (PCR), and a laser fluorescence device, DIAGNOdent. Dentin was removed every 300 micro m in the direction of the pulp chamber in 10 extracted molars with occlusal dentin caries and 3 extracted sound molars. Dentin surfaces were evaluated using DIAGNOdent, and dentinal tissue samples were removed by using a round bur before and after each removal.