Combined surgical-orthodontic and prosthetic treatment of a partially edentulous patient with skeletal Class III malocclusion

学術論文(Ariticle)journal articl

<ORIGINAL ARTICLE>Localization of anti-monocyte/macrophage antibody-positive cells in periodontal tissue of rat maxillary molars after orthodontic tooth movement

To examine the localization of monoclonal anti-monocyte/macrophage (ED1) and macrophage (ED2) antibody-positive cells in periodontium, rat maxillary molar teeth were moved by insertion of band materials. The orthodontic tooth movement was elicited for 5 days, and paraffin-embedded maxillary teeth were stained by fluorescent immunocytochemistry and observed using a confocal laser scanning microscope. The localization of ED1-positive mononuclear cells in the experimental teeth was little different from that in the controls. While ED2-positive mononuclear cells were located throughout the periodontium on the distalside of controls, the number of positive cells decreased on the pressure side of the treated teeth. The present study suggested that most of the immunoreactive mononuclear cells on the distal side of controls are macrophages, while the positive cells on the pressure side of the experimental teeth are osteoclast precursors and a small number of macrophages

Bending and torsional properties of commercial nickel-titanium orthodontic wires

The aim of this study was to investigate the force delivery for a variety of types and sizes of commercially available nickel-titanium wires. The relationship of the magnitude of the force and the tooth displacement in a severe crowding case is discussed. Nine brands of nickel-titanium orthodontic wires in a variety of sizes were examined with a three-point bending test and a torsion test at 37℃. Most wires exhibited superelastic behavior for the three-point bending and torsion tests at 37℃. In the three-point bending test, the variation of the average load at 1.5mm deflection during unloading ranged from 0kgf for Copper Ni-Ti 40℃ with a 0.016×0.022 inch cross-section to 0.46kgf for ORTHO LINE with a 0.021×0.025 inch cross-section. The average torsion load at a rotation of 30°on deactivation varied from 0kgf-cm for Copper Ni-Ti 40℃ to 0.023kgf-cm for ORTHO LINE. The predicted torsional angles for the maxillary arch in the severe crowding case were smaller than expected and only three positions exceeded 20°. Considering the play between bracket slots and archwire, nickel-titanium orthodontic wires of the superelastic type may not exhibit superelastic properties for torsion in most clinical situations

咀嚼運動における平均経路予測モデルの開発

The purpose of this study was to develop a new statistical model to predict mandibular kinematics, especially for chewing cycles. Two subjects without indicators or symptoms of temporomandibular disorders and with normal occlusion and anterior crossbite were selected. The chewing movement of the mouth was recorded by an opto-electric system (TRIMET system). Each curve was modeled as spline function with random coefficients. To determine the optimal number of knots, two criteria were used : DIC (deviance information criteria) and pD (effective number of parameters). The aim was to estimate a typical population curve. Self-modeling regression (SEMOR) was extended to three dimensions to model groups of three-dimensional curves. Each curve was modeled as a spline function using 25 knots, and a population average curve was created using SEMOR. The chewing cycles were modeled using a combination of spline function with random coefficients and SEMOR. These models provide a new tool for the analysis of mandibular kinematics to understand commonalities and difference among subjects

仮想歯列モデルを用いた歯と歯列弓形態の評価

The aim of this study was to clarify the three-dimensional (3D) morphological characteristics of dentition using a virtual model of dental arches. Full-mouth dental cast sets were prepared from 217 volunteers (121 male and 96 female). Dental casts were scanned by optTOP-HE scanner. The 3D models were measured and analyzed with Rapidform 2004 software. For the measurements of four morphological parameters(maxillary and mandibular arch lengths, width and first molar width), linear regressions were performed using each variable as the predictor and each other variable as the outcome. In all parameters, the male group showed higher values than the female groups. In the case of the combined and male groups, correlation coefficients of all items were statistically significant (P<0.01). The approach used in this study provides a reliable reference point definition and may provide basic information for dentistry

Development of a safe and quick method for removal of intermaxillary fixation with superelastic Ni-Ti wire

To improve emergency intermaxillary fixation release, a novel method of intermaxillary fixation, in which super-elastic nickel-titan (Ni-Ti) alloy wires were applied at 2 places (Method A) was developed. Method A was compared to the previous method (Method B : fixing the jaw at 3 places with stainless steel wires), in terms of the time required to remove the wires and the number of pieces of cut wire left in the oral cavity and pharynx. The average time for removing the wires was 14.5 ± 9.9 (mean ± SD) seconds for Method A, and 79.1 ± 53.1 seconds for Method B. The average time was significantly shorter in Method A than in Method B (p < 0.01). The number of pieces of cut wire left was zero with Method A. These findings suggest that the novel method (Method A) provides quick and safe wire removal and improves the safety and quality of dentistry in emergency cases

Azilsartan inhibits inflammation-triggered bone resorption and osteoclastogenesis in vivo via suppression of TNF-α expression in macrophages

IntroductionHypertension is a major risk factor for cardiovascular disease (CVD) and is associated with increased bone loss due to excessive activity of the local renin-angiotensin system (RAS). Angiotensinogen/Angiotensin (ANG) II/Angiotensin II type 1 receptor (AT1R) axis is considered as the core axis regulating RAS activity. Azilsartan is an FDA-approved selective AT1R antagonist that is used to treat hypertension. This study aimed to determine whether azilsartan affects formation of osteoclast, resorption of bone, and the expression of cytokines linked with osteoclastogenesis during lipopolysaccharide (LPS)-triggered inflammation in vivo.MethodsIn vivo, following a 5-day supracalvarial injection of LPS or tumor necrosis factor-alpha (TNF-α) with or without azilsartan, the proportion of bone resorption and the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells, which are identified as osteoclasts on mice calvariae were counted. The mRNA expression levels of TRAP, cathepsin K, receptor activator of NF-κB ligand (RANKL), and TNF-α were also evaluated. In vitro, the effect of azilsartan (0, 0.01, 0.1, 1, and 10 μM) on RANKL and TNF-α-triggered osteoclastogenesis were investigated. Also, whether azilsartan restrains LPS-triggered TNF-α mRNA and protein expression in macrophages and RANKL expression in osteoblasts were assessed. Furthermore, western blotting for analysis of mitogen-activated protein kinases (MAPKs) signaling was conducted.ResultsAzilsartan-treated calvariae exhibited significantly lower bone resorption and osteoclastogenesis than those treated with LPS alone. In vivo, LPS with azilsartan administration resulted in lower levels of receptor activator of RANKL and TNF-α mRNA expression than LPS administration alone. Nevertheless, azilsartan did not show inhibitory effect on RANKL- and TNF-α-triggered osteoclastogenesis in vitro. Compared to macrophages treated with LPS, TNF-α mRNA and protein levels were lower in macrophages treated by LPS with azilsartan. In contrast, RANKL mRNA and protein expression levels in osteoblasts were the same in cells co-treated with azilsartan and LPS and those exposed to LPS only. Furthermore, azilsartan suppressed LPS-triggered MAPKs signaling pathway in macrophages. After 5-day supracalvarial injection, there is no difference between TNF-α injection group and TNF-α with azilsartan injection group.ConclusionThese findings imply that azilsartan prevents LPS-triggered TNF-α production in macrophages, which in turn prevents LPS-Triggered osteoclast formation and bone resorption in vivo