Strategic treatment planning for anterior open bite: A comprehensive approach.

Anterior open bite (AOB), characterized by the lack of vertical overlap between upper and lower anterior teeth, poses a considerable challenge in orthodontics. The condition depends on many factors that combine to render it difficult to achieve post treatment stability. AOB is commonly classified as dental, skeletal, or functional on the basis of the clinical presentation and causative factors. Traditionally, skeletal AOB necessitates surgical intervention, whereas nonsurgical approaches such as extrusion arches and the Multiloop Edgewise Archwire Technique (MEAW) can be employed in more straightforward cases. Functional appliances are reserved for situations in which a patient's growth potential offers the possibility of effectively addressing AOB. This review presents a strategic treatment approach for addressing AOB, taking into account the classification and severity of the condition. The proposed SHE framework describes the use of mini-screws (S) for anchorage and vertical control, encouragement to correct habits (H), and the utilization of extractions and elastics (E). By incorporating extra-radicular mini-screws, AOB closure is achieved through anterior retraction in extraction cases or whole arch distalization of dentition with elastics in non-extraction cases. This framework emphasizes habit correction through a regimen of oral myofunctional therapy (OMT) and habit-correcting appliances to enhance posttreatment stability. This review suggests that nonsurgical correction is viable in the majority of cases, whereas surgical intervention should be reserved for severe cases of skeletal vertical overgrowth or horizontal discrepancies.

Changes in smile parameters after surgical-orthodontic treatment for skeletal Class III malocclusion.

Background/purpose: Many patients pursue attractive smiles, and surgical-orthodontic treatment is a common method. We aimed to analyze the changes in smile parameters after surgical-orthodontic treatment in patients with skeletal Class III pattern and identify factors influencing postoperative outcomes. Materials and methods: This retrospective study comprised 34 patients with skeletal Class III malocclusion and pure mandible prognathism who received surgical-orthodontic treatment. Hard and soft tissue parameters were assessed through lateral cephalometry, and smile esthetics were evaluated through extraoral photography. Postoperative changes in smile parameters and between-parameter correlations were analyzed. Random forest and decision tree deep learning models were used to identify factors influencing postoperative changes. Results: Substantial postoperative changes were observed in the buccal corridor, upper lip height, and smile index. Significant between-sex differences were noted in the upper midline and right chelion. Strong, positive correlations were found between upper lip height and upper lip ratio and between lower lip height and lower lip ratio. By contrast, strong negative correlations were observed between lower teeth exposure and smile index and between interlabial gap and smile index. The highest degrees of postoperative changes were noted in asymmetry-associated smile parameters: lower lip area, interlabial gap, smile index, buccal corridor, and arc ratio. Conclusion: Considerable changes were noted in skeletal, dental, and soft tissue parameters after surgical-orthodontic treatment. However, the changes in smile esthetics were less prominent from the frontal view. As for chin asymmetry, the most to least prominent changes were in the lower lip area, interlabial gap, smile index, buccal corridor, and arc ratio, respectively.

Organic light-emitting diode therapy promotes longevity through the upregulation of SIRT1 in senescence-accelerated mouse prone 8 mice.

Phototherapy has been extensively used to prevent and treat signs of aging and stimulate wound healing, and phototherapy through light-emitting diodes (LEDs). In contrast to LED, organic LED (OLED) devices are composed of organic semiconductors that possess novel characteristics. We investigated the regenerative potential of OLED for restoring cellular potential from senescence and thus delaying animal aging. Bone marrow-derived stem cells (BMSCs) and adipose-derived stem cells (ADSCs) were isolated from the control and OLED- treated groups to evaluate their proliferation, migration, and differentiation potentials. Cellular senescence was evaluated using a senescence-associated ß-galactosidase (SA-ß-gal) activity assay and gene expression biomarker assessment. OLED treatment significantly increased the cell proliferation, colony formation, and migration abilities of stem cells. SA-ß-gal activity was significantly decreased in both ADSCs and BMSCs in the OLED-treated group. Gene expression biomarkers from treated mice indicated a significant upregulation of IGF-1 (insulin growthfactor-1). The upregulation of the SIRT1 gene inhibited the p16 and p19 genes then to downregulate the p53 expressions for regeneration of stem cells in the OLED-treated group. Our findings indicated that the survival rates of 10-month aging senescence-accelerated mouse prone 8 mice were prolonged and that their gross appearance improved markedly after OLED treatment. Histological analysis of skin and brain tissue also indicated significantly greater collagen fibers density, which prevents ocular abnormalities and ß-amyloid accumulation. Lordokyphosis and bone characteristics were observed to resemble those of younger mice after OLED treatment. In conclusion, OLED therapy reduced the signs of aging and enhanced stem-cell senescence recovery and then could be used for tissue regeneration.

Anti-Colorectal Cancer Effects of Fucoidan Complex-Based Functional Beverage Through Retarding Proliferation, Cell Cycle and Epithelial-Mesenchymal Transition Signaling Pathways.

BACKGROUND: Fucus vesiculosus-derived fucoidan, a multifunctional bioactive polysaccharide sourced from marine organisms, exhibits a wide range of therapeutic properties, including its anti-tumor effects. While previous research has reported on its anti-cancer potential, limited studies have explored its synergistic capabilities when combined with other natural bioactive ingredients. In this current study, we present the development of an integrative functional beverage, denoted as VMW-FC, which is composed of a fucoidan complex (FC) along with a blend of various herbal components, including vegetables (V), mulberries and fruits (M), and spelt wheat (W). OBJECTIVE: Colorectal cancer (CRC) remains a significant cause of mortality, particularly in metastatic cases. Therefore, the urgent need for novel alternative medicines that comprehensively inhibit CRC persists. In this investigation, we assess the impact of VMW-FC on CRC cell proliferation, cell cycle dynamics, metastasis, in vivo tumorigenesis, and potential side effects. METHODS: Cell growth was assessed using MTT and colony formation assays, while metastatic potential was evaluated through wound healing and transwell migration assays. The underlying signaling mechanisms were elucidated through qPCR and western blot analysis. In vivo tumor formation and potential side effects were evaluated using a subcutaneous tumor-bearing NOD/SCID mouse model. RESULTS: Our findings demonstrate that VMW-FC significantly impedes CRC proliferation and migration in a dose- and time-dependent manner. Furthermore, it induces sub-G1 cell cycle arrest and an increase in apoptotic cell populations, as confirmed through flow-cytometric analysis. Notably, VMW-FC also suppresses xenograft tumor growth in NOD/SCID mice without causing renal or hepatic toxicity. CONCLUSION: The integrative herbal concoction VMW-FC presents a promising approach for inhibiting CRC by slowing proliferation and migration, inducing cell cycle arrest and apoptosis, and suppressing markers associated with proliferation (Ki-67, PCNA, and CDKs) and epithelial-mesenchymal transition (EMT) (Vimentin, N-cadherin, and ß-catenin).

Physicochemical Characterization, Biocompatibility, and Antibacterial Properties of CMC/PVA/Calendula officinalis Films for Biomedical Applications.

This study reports a carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA) composite film that incorporates Calendula officinalis (CO) extract for biomedical applications. The morphological, physical, mechanical, hydrophilic, biological, and antibacterial properties of CMC/PVA composite films with various CO concentrations (0.1%, 1%, 2.5%, 4%, and 5%) are fully investigated using different experiments. The surface morphology and structure of the composite films are significantly affected by higher CO concentrations. X-ray diffraction (XRD) and Fourier transform infrared spectrometry (FTIR) analyses confirm the structural interactions among CMC, PVA, and CO. After CO is incorporated, the tensile strength and elongation upon the breaking of the films decrease significantly. The addition of CO significantly reduces the ultimate tensile strength of the composite films from 42.8 to 13.2 MPa. Furthermore, by increasing the concentration of CO to 0.75%, the contact angle is decreased from 15.8° to 10.9°. The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay reveals that the CMC/PVA/CO-2.5% and CMC/PVA/CO-4% composite films are non-cytotoxic to human skin fibroblast cells, which is favorable for cell proliferation. Remarkably, 2.5% and 4% CO incorporation significantly improve the inhibition ability of the CMC/PVA composite films against Staphylococcus aureus and Escherichia coli. In summary, CMC/PVA composite films containing 2.5% CO exhibit the functional properties for wound healing and biomedical engineering applications.

Hard Anodization Film on Carbon Steel Surface by Thermal Spray and Anodization Methods.

In this paper, we used two mass-produced industrial technologies, namely, thermal spraying and anodization methods, to enhance the surface characteristics of AISI 1045 medium carbon steel for use in special environments or products. The anodic film can effectively improve the surface properties of carbon steel. A sequence of treatments of the carbon steel substrate surface that consist of sandblasting, spraying the aluminum film, annealing, hot rolling, cleaning, grinding, and polishing can increase the quality of the anodized film. This paper proposes an anodization process for the surface of carbon steel to increase the corrosion resistance, hardness, color diversification, and electrical resistance. The resulting surface improves the hardness (from 170 HV to 524 HV), surface roughness (from 1.26 to 0.15 µm), coloring (from metal color to various colors), and corrosion resistance (from rusty to corrosion resistant). The electrochemical corrosion studies showed that the AISI 1045 steel surface with a hard anodized film had a lower corrosion current density of 10-5.9 A/cm2 and a higher impedance of 9000 ohm than those of naked AISI 1045 steel (10-4.2 A/cm2 and 150 ohm) in HCl gas.

Amelioration of Nicotine-Induced Osteoarthritis by Platelet-Derived Biomaterials Through Modulating IGF-1/AKT/IRS-1 Signaling Axis.

Besides inhalation, a few studies have indicated that the uptake of nicotine through air or clothing may be a significant pathway of its exposure among passive smokers. Nicotine is well known to exert various physiological impacts, including stimulating sympathetic nervous system, causing vascular disturbances, and inducing cell death. Therefore, we aimed to establish whether exposure of nicotine could induce articular cartilage degeneration in a mouse model of osteoarthritis (OA). We specifically assessed dose-dependent effect of nicotine in vitro to mimic its accumulation. Further, during the in vivo studies, mice subcutaneously administered with nicotine was examined for OA-associated pathologic changes. We found that nicotine significantly suppressed chondrocytes and chondrogenic markers (Sox, Col II, and aggrecan). Nicotine-treated mice also showed altered knee joint ultrastructure with reduced Col II and proteoglycans. After corroborating nicotine-induced OA characteristics, we treated this pathologic condition through employing platelet-derived biomaterial (PDB)-based regenerative therapy. The PDB significantly suppressed OA-like pathophysiological characteristics by 4 weeks. The mechanistic insight underlying this therapy demonstrated that PDB significantly restored levels of insulin-like growth factor 1 (IGF-1) signaling pathway proteins, especially pIGF-1 R, pAKT, and IRS-1, regulating extracellular matrix synthesis by chondrocytes. Taken together, the PDB exerts regenerative and reparative activities in nicotine-mediated initiation and progression of OA, through modulating IGF-1/AKT/IRS-1 signaling axis.

Photoelastic analysis of stress distributions in the root-bone interface when applying various orthodontic methods to subside lower anterior crowding.

Dental crowding is a prevalent problem in modern society. Various factors, including different bracket systems and geometry of wire, influence the outcome using superelastic wire in the alignment stage of treatment. Currently, the use of light round wire instead of large-sized rectangular wire is emphasized to avoid powerful torsional stiffness. However, these guidelines lack scientific evidence for support. They have been written predominantly based on clinical experience. Therefore, the purpose of this study was to evaluate how factors such as bracket systems and wire geometry affect the stress distribution at the root-bone interface. Models using a photoelastic material (PL-3) to simulate bone tissue were fabricated. The simulated teeth were arranged as in lower anterior crowding. Then, the crowded teeth were subjected to orthodontic treatment with various types of bracket, ligating approaches using ligature wires of different sizes, shapes, and materials. Photoelastic images of the bone area of the models were obtained and compared. The results showed that wire size plays a more significant role than the material or cross-sectional shape of the wire in affecting the stress distribution at the simulated root-bone interface. The teeth ligated with a larger cross-sectional diameter of wire showed the application of excessive torque, which may cause root resorption and slow down tooth movement. These results not only demonstrate the scientific evidence backing clinical experience but also can be a useful reference for further clinical application.

In Vitro Biocompatibility, Radiopacity, and Physical Property Tests of Nano-Fe3O4 Incorporated Poly-l-lactide Bone Screws.

The aim of this study was to fabricate biodegradable poly-l-lactic acid (PLLA) bone screws containing iron oxide (Fe3O4) nanoparticles, which are radiopaque and 3D-printable. The PLLA composites were fabricated by loading 20%, 30%, and 40% Fe3O4 nanoparticles into the PLLA. The physical properties, including elastic modulus, thermal properties, and biocompatibility of the composites were tested. The 20% nano-Fe3O4/PLLA composite was used as the material for fabricating the 3D-printed bone screws. The mechanical performance of the nano-Fe3O4/PLLA bone screws was evaluated by anti-bending and anti-torque strength tests. The tissue response and radiopacity of the nano-Fe3O4/PLLA bone screws were assessed by histologic and CT imaging studies using an animal model. The addition of nano-Fe3O4 increased the crystallization of the PLLA composites. Furthermore, the 20% nano-Fe3O4/PLLA composite exhibited the highest thermal stability compared to the other Fe3O4 proportions. The 3D-printed bone screws using the 20% nano-Fe3O4/PLLA composite provided excellent local tissue response. In addition, the radiopacity of the 20% nano-Fe3O4/PLLA screw was significantly better compared with the neat PLLA screw.

Innovative design of closing loops producing an optimal force system applicable in the 0.022-in bracket slot system.

INTRODUCTION: Most closing loops designed for producing higher moment-to-force (M/F) ratios require complex wire bending and are likely to cause hygiene problems and discomfort because of their complicated configurations. We aimed to develop a simple loop design that can produce optimal force and M/F ratio. METHODS: A loop design that can generate a high M/F ratio and the ideal force level was investigated by varying the portion and length of the cross-sectional reduction of a teardrop loop and the loop position. The forces and moments acting on closing loops were calculated using structural analysis based on the tangent stiffness method. RESULTS: An M/F ratio of 9.3 (high enough to achieve controlled movement of the anterior teeth) and an optimal force level of approximately 250 g of force can be generated by activation of a 10-mm-high teardrop loop whose cross-section of 0.019 × 0.025 or 0.021 × 0.025 in was reduced in thickness by 50% for a distance of 3 mm from the apex, located between a quarter and a third of the interbracket distance from the canine bracket. CONCLUSIONS: The simple loop design that we developed delivers an optimal force and an M/F ratio for the retraction of anterior teeth, and is applicable in a 0.022-in slot system.

Biomechanical aspects of segmented arch mechanics combined with power arm for controlled anterior tooth movement: A three-dimensional finite element study.

The porpose of this study was to determine the optimal length of power arms for achieving controlled anterior tooth movement in segmented arch mechanics combined with power arm. A three-dimensional finite element method was applied for the simulation of en masse anterior tooth retraction in segmented power arm mechanics. The type of tooth movement, namely, the location of center of rotation of the maxillary central incisor in association with power arm length, was calculated after the retraction force was applied. When a 0.017 × 0.022-in archwire was inserted into the 0.018-in slot bracket, bodily movement was obtained at 9.1 mm length of power arm, namely, at the level of 1.8 mm above the center of resistance. In case a 0.018 × 0.025-in full-size archwire was used, bodily movement of the tooth was produced at the power arm length of 7.0 mm, namely, at the level of 0.3 mm below the center of resistance. Segmented arch mechanics required shorter length of power arms for achieving any type of controlled anterior tooth movement as compared to sliding mechanics. Therefore, this space closing mechanics could be widely applied even for the patients whose gingivobuccal fold is shallow. The segmented arch mechanics combined with power arm could provide higher amount of moment-to-force ratio sufficient for controlled anterior tooth movement without generating friction, and vertical forces when applying retraction force parallel to the occlusal plane. It is, therefore, considered that the segmented power arm mechanics has a simple appliance design and allows more efficient and controllable tooth movement.

Effect of bracket slot and archwire dimensions on anterior tooth movement during space closure in sliding mechanics: a 3-dimensional finite element study.

INTRODUCTION: It has been found that controlled movement of the anterior teeth can be obtained by attaching a certain length of power arm onto an archwire in sliding mechanics. However, the impact of the archwire/bracket play on anterior tooth movement has not been clarified. The purpose of this study was to compare the effect of the power arm on anterior tooth movements with different dimensions of bracket slots and archwires. METHODS: A 3-dimensional finite element method was used to simulate en-masse anterior tooth retraction in sliding mechanics. Displacements of the maxillary central incisor and the archwire deformation were calculated when applying retraction forces from different lengths of power arms. RESULTS: When a 0.017 × 0.022-in archwire was engaged into the 0.018-in slot bracket, bodily movement of the incisor was obtained with 9.1-mm length of the power arm. When a 0.022-in slot system was coupled with a 0.019 × 0.025-in archwire, bodily movement was observed with a power arm length of 11.6 mm. CONCLUSIONS: Archwire/bracket play has a remarkable impact on anterior tooth movement. An effective torque application to the anterior teeth becomes clinically difficult in sliding mechanics combined with power arms when the archwire/bracket play is large.

Effect of play between bracket and archwire on anterior tooth movement in sliding mechanics: A three-dimensional finite element study.

OBJECTIVES: The aim of this study was to clarify the effect of the play between the bracket and the archwire on anterior tooth movement subjected to the retraction force from various lengths of power arms in sliding mechanics. MATERIALS AND METHODS: A three-dimensional finite element method was used to simulate en masse anterior tooth retraction in sliding mechanics. The displacements of the maxillary incisor and the archwire deformation were calculated when the retraction force was applied. RESULTS: When a play did not exist, bodily movement was obtained at 5.0 mm length of power arm. In case a play existed, bodily movement was observed at the power arm length of 11.0 mm. CONCLUSIONS: In the actual clinical situation, a bracket/archwire play and the torsion of the archwire within the bracket slot should be taken into consideration to prescribe an optimal power arm length and to achieve effective anterior tooth movement.

Effects of cryopreservation of intact teeth on the isolated dental pulp stem cells.

INTRODUCTION: Human dental pulp stem cells (DPSCs) have been reported to be useful material for future regenerative medicine. Clinically, cryopreservation of intact teeth can successfully preserve the periodontal ligament for future autotransplantation; however, the effects of cryopreservation procedure on the properties of DPSCs are still unclear. The aim of this study was to test whether DPSCs isolated from cryopreserved teeth can express stem cell-specific markers. METHODS: In this study, a novel programmable freezer coupled to a magnetic field was used to perform the cryopreservation experiments. The tested DPSCs were isolated from magnetically cryopreserved and non-cryopreserved fresh teeth with an enzyme digestion procedure. The success rate of isolation, growth curves, morphology, stem cell-specific markers, and the differentiation capacity of the isolated cells were evaluated and compared. RESULTS: The isolation rate of dental pulp cells from magnetically cryopreserved teeth was 73%. After culture for 5 generations, there was no significant difference in cell viability between cells isolated from magnetically cryopreserved teeth and those isolated from fresh teeth. There were also no visible differences between the 2 groups of dental pulp cells in morphology, expression of stem cell markers, or osteogenic and adipogenic differentiations. CONCLUSIONS: The results suggest that cryopreserved whole teeth can be used for autotransplantation and provide a viable source of DPSCs.