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Quenched or frozen-in structural disorder is ubiquitous in real experimental systems. Much of the progress is achieved in understanding the phase separation of such systems using the diffusion-driven coarsening in an Ising model with quenched disorder. But there is a paucity of research on the phase-separation kinetics in fluids with quenched disorder. In this paper, we present results from a detailed molecular dynamics simulation, showing the effects of randomly placed localized impurities on the phase separation kinetics of binary fluid mixtures. Two different models are offered for representing the impurities. We observe a dramatic slowing down in the pattern formation with increasing impurity concentration. This sluggish domain growth kinetics follows a power-law with a disorder-dependent exponent. The correlation function and structure factor show a non-Porod behavior, indicating the roughening of the domain interfaces. We have also studied the effect of quenched disorder on the aging dynamics by calculating the two-time order parameter auto correlation function and find that the Fisher and Huse scaling law holds good in the presence of quenched disorder.
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BACKGROUND: This study investigates the contamination level, spatial distribution, pollution sources, potential ecological risks, and human health risks associated with heavy metal(loid)s (i.e., arsenic (As), copper (Cu), iron (Fe), manganese (Mn), lead (Pb), and zinc (Zn)) in surface soils within the mining region of Matehuala, located in central Mexico. OBJECTIVES: The primary objectives are to estimate the contamination level of heavy metal(loid)s, identify pollution sources, assess potential ecological risks, and evaluate human health risks associated with heavy metal(loid) contamination. METHODS: Soil samples from the study area were analysed using various indices including Igeo, Cf, PLI, mCd, EF, and PERI to evaluate contamination levels. Source apportionment of heavy metal(loid)s was conducted using the APCS-MLR and PMF receptor models. Spatial distribution patterns were determined using the most efficient interpolation technique among five different approaches. The total carcinogenic risk index (TCR) and total non-carcinogenic index (THI) were used in this study to assess the potential carcinogenic and non-carcinogenic hazards posed by heavy metal(loid)s in surface soil to human health. RESULTS: The study reveals a high contamination level of heavy metal(loid)s in the surface soil, posing considerable ecological risks. As was identified as a priority metal for regulatory control measures. Mining and smelting activities were identified as the primary factors influencing heavy metal(loid) distributions. Based on spatial distribution mapping, concentrations were higher in the northern, western, and central regions of the study area. As and Fe were found to pose considerable and moderate ecological risks, respectively. Health risk evaluation indicated significant levels of carcinogenic risks for both adults and children, with higher risks for children. CONCLUSION: This study highlights the urgent need for monitoring heavy metal(loid) contamination in Matehuala's soils, particularly in regions experiencing strong economic growth, to mitigate potential human health and ecological risks associated with heavy metal(loid) pollution.
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Monitoramento Ambiental , Metais Pesados , Mineração , Poluentes do Solo , México , Poluentes do Solo/análise , Medição de Risco , Metais Pesados/análise , Humanos , Monitoramento Ambiental/métodosRESUMO
PURPOSE: This review aims to summarize the current knowledge concerning the clinical features, diagnostic work-up, and therapeutic approach of uveitic epiretinal membranes (ERM). METHODS: A thorough investigation of the literature was conducted using the PubMed database. Additionally, a complementary search was carried out on Google Scholar to ensure the inclusion of all relevant items in the collection. RESULTS: ERM is an abnormal layer at the vitreoretinal interface, resulting from myofibroblastic cell proliferation along the inner surface of the central retina, causing visual impairment. Known by various names, ERM has diverse causes, including idiopathic or secondary factors, with ophthalmic imaging techniques like OCT improving detection. In uveitis, ERM occurrence is common, and surgical intervention involves pars plana vitrectomy with ERM peeling, although debates persist on optimal approaches. CONCLUSIONS: Histopathological studies and OCT advancements improved ERM understanding, revealing a diverse group of diseases without a unified model. Consensus supports surgery for uveitic ERM in progressive cases, but variability requires careful consideration and effective inflammation management. OCT biomarkers, deep learning, and surgical advances may enhance outcomes, and medical interventions and robotics show promise for early ERM intervention.
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Membrana Epirretiniana , Tomografia de Coerência Óptica , Uveíte , Vitrectomia , Humanos , Membrana Epirretiniana/diagnóstico , Membrana Epirretiniana/cirurgia , Membrana Epirretiniana/etiologia , Uveíte/diagnóstico , Uveíte/complicações , Vitrectomia/métodos , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Gerenciamento ClínicoRESUMO
The development of sensing technologies and miniaturization allows for the development of smart systems with elevated sensing performance. Silicon-based hydrogen sensors have received a lot of attention due to its electrical conductivity and the mechanical endurance. With this motivation, we have proposed a two-terminal silicon-based device in a crossbar architecture as a hydrogen gas sensing platform. In this work, we have adopted a multi-layer modeling approach to analyze the performance of the proposed system. Technology computer-aided design models have been used to capture device performance. A gas sensor model based on hydrogen adsorption on the Palladium surface and a crossbar model has been adopted to understand the Palladium work function variation with gas pressure and the performance of the proposed crossbar system respectively. We have shown the impact of parameters like interconnect resistance and array size on the whole system's performance. Finally, a comprehensive analysis has been provided for the design rule of this architecture. A fabrication process to spur future experimental works has also been added. This work will provide computational insight into the performance of a crossbar hydrogen sensor system, optimized against some critical parameters.
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When an amorphous solid is deformed homogeneously, it exhibits heterogeneous plastic instabilities with a localized cooperative rearrangement of a cluster of particles in response. The heterogeneous behavior plays an important role in deciding the mechanical properties of amorphous solids. In this paper, we employ computer simulations to study the characteristics and the spatial correlations of these clusters characterized by their non-affine displacements in amorphous solids under simple shear deformation in the athermal quasistatic limit. The clusters with large displacements are found to be homogeneously distributed in space in the elastic regime, followed by a localization within a system-spanning shear band after yielding. The distributions of the displacement field exhibit a power-law nature in the elastic regime with an exponential cutoff post yielding. The non-affine displacements show strong spatial correlations, which become long-ranged with increasing strain. From our results, it is evident that the decay of the correlation functions is exponential in nature in the elastic regime. The yielding transition is marked by an abrupt change in the decay after which it is well described by a power-law with an exponential cutoff. These results demonstrate a scale-free character of non-affine correlations in the steady flow regime. These results are found to be robust and independent of the strain window over which the total non-affine displacement is calculated.
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Matrix metalloproteinase-9 (MMP9) and total amyloid-beta (Aß) are prospective biomarkers of ocular ageing and retinopathy. These were quantified by ELISA in the vitreous and blood from controls (n = 55) and in a subset of age-related macular degeneration (AMD) patients (n = 12) for insights and possible additional links between the ocular and systemic compartments. Vitreous MMP9 levels in control and AMD groups were 932.5 ± 240.9 pg/mL and 813.7 ± 157.6 pg/mL, whilst serum levels were 2228 ± 193 pg/mL and 2386.8 ± 449.4 pg/mL, respectively. Vitreous Aß in control and AMD groups were 1173.5 ± 117.1 pg/mL and 1275.6 ± 332.9 pg/mL, whilst plasma Aß were 574.3 ± 104.8 pg/mL and 542.2 ± 139.9 pg/mL, respectively. MMP9 and Aß showed variable levels across the lifecourse, indicating no correlation to each other or with age nor AMD status, though the smaller AMD cohort was a limiting factor. Aß and MMP9 levels in the vitreous and blood were unrelated to mean arterial pressure. Smoking, another modifiable risk, showed no association with vitreous Aß. However, smoking may be linked with vitreous (p = 0.004) and serum (p = 0.005) MMP9 levels in control and AMD groups, though this did not reach our elevated (p = 0.001) significance. A bioinformatics analysis revealed promising MMP9 and APP/Aß partners for further scrutiny, many of which are already linked with retinopathy.
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Degeneração Macular , Metaloproteinase 9 da Matriz , Humanos , Peptídeos beta-Amiloides , Biomarcadores , Ensaio de Imunoadsorção EnzimáticaRESUMO
This study aimed to rigorously investigate and integrate the underlying hypothesis that an enhancing effect of gibberellic acid (GA3, 3 µM) with increased growth actually leads to a modification of the physiological role of polyamines during salinity stress (NaCl, 100 mM) in fennel. These analyses concern both reserve tissues (cotyledons) and embryonic axes in growth. Physiological results indicate a restriction of germination, growth, mineral nutrition and damages to membranes of salt-treated seedlings. This was partially attenuated in seedlings treated with an interaction effect of GA3 and NaCl. Peroxidase and catalase activities showed a reduction or an augmentation according to the treatments and organs. The three main polyamines (PA): putrescine, spermidine and spermine were elevated in the salt-treated seedlings. Meanwhile, GA3 seed priming was extremely efficient in reducing PA levels in salt-stressed seedlings compared to the control. Response of PA genes to salinity was variable. Up-regulation was noted for SPMS1, ODC1, and ADC1 in hypocotyls and cotyledons (H + C) and down-regulation for SAMDC1 in the radicle. Interaction of salt/GA3 treatment showed different responses, only ODC1 in (H + C) and ADC1 in both radicle and (H + C) were overexpressed. Concerning other genes, no change in mRNA abundance was observed in both organs compared to the salt-treated seedlings. From these results, it could be inferred that the fennel seedlings were NaCl sensitive. This sensitivity was mitigated when GA3 applied for seed priming and applied in combination with NaCl, which resulted in a reduction of the PA content. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01140-4.
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[This corrects the article DOI: 10.1007/s12298-022-01140-4.].
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Plant protein kinases form redundant signaling pathways to perceive microbial pathogens and activate immunity. Bacterial pathogens repress cellular immune responses by secreting effectors, some of which bind and inhibit multiple host kinases. To understand how broadly bacterial effectors may bind protein kinases and the function of these kinase interactors, we first tested kinase-effector (K-E) interactions using the Pseudomonas syringae pv. tomato-tomato pathosystem. We tested interactions between five individual effectors (HopAI1, AvrPto, HopA1, HopM1, and HopAF1) and 279 tomato kinases in tomato cells. Over half of the tested kinases interacted with at least one effector, and 48% of these kinases interacted with more than three effectors, suggesting a role in the defense. Next, we characterized the role of select multi-effector-interacting kinases and revealed their roles in basal resistance, effector-triggered immunity (ETI), or programmed cell death (PCD). The immune function of several of these kinases was only detectable in the presence of effectors, suggesting that these kinases are critical when particular cell functions are perturbed or that their role is typically masked. To visualize the kinase networks underlying the cellular responses, we derived signal-specific networks. A comparison of the networks revealed a limited overlap between ETI and basal immunity networks. In addition, the basal immune network complexity increased when exposed to some of the effectors. The networks were used to successfully predict the role of a new set of kinases in basal immunity. Our work indicates the complexity of the larger kinase-based defense network and demonstrates how virulence- and avirulence-associated bacterial effectors alter sectors of the defense network.
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Proteínas Quinases/fisiologia , Solanum lycopersicum/imunologia , Fatores de Virulência/imunologia , Proteínas de Bactérias/metabolismo , Interações Hospedeiro-Patógeno , Solanum lycopersicum/genética , Doenças das Plantas/microbiologia , Imunidade Vegetal/fisiologia , Proteínas de Plantas/metabolismo , Proteínas Quinases/imunologia , Pseudomonas syringae/patogenicidade , Transdução de Sinais , VirulênciaRESUMO
We study the mechanical properties and pore structure in a three-dimensional molecular dynamics model of porous glass under athermal quasistatic shear. The vitreous samples are prepared by rapid thermal quenching from a high-temperature molten state. The pore structures form via solid-gas phase separation. The quiescent samples exhibit a wide range of pore topography, from inter-connected pore networks to randomly distributed compact pores depending on the material density. We find that the shear modulus strongly depends on the density and porosity. Under mechanical loading, the pore structure rearranges which is reflected in the pore size distribution function. Our results show that with increase in strain the distribution widens as the adjacent pores coalesce and form larger pores. We also propose a universal scaling law for the pore size distribution function which offers excellent data collapse for highly porous materials in the undeformed case. From the data scaling, we identify a critical density that can be attributed to the transition point from a porous-type to bulk-type material. The validity of the scaling law under finite deformation is also analyzed.
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Electromagnetic energy is the "backbone" of wireless communication systems, and its progressive use is considered to have a low but measurable impact on a wide range of biological systems. Even though a growing amount of data has reported electromagnetic energy absorption in humans along with subsequent biological effects, the consequences of electromagnetic energy absorption on plants have been insufficiently addressed. The higher surface to volume ratio along with the enormous water-ion concentrations makes the plant an ideal model to interact with non-ionizing electromagnetic radiation. In this study, controlled and periodic electromagnetic exposure of 1837.50 MHz, 2.75 W/m2 for 6 h a day on a popular rice variety (var. Satabdi) reduced the seed germination rate. The same dose of periodic electromagnetic exposure upregulated phytochrome B and phytochrome C gene transcripts in 12-day-old seedlings, whereas, in 32-day-old plants, the dose upregulated calmodulin and phytochrome C while the bZIP1 gene showed repression. However, the transcript abundance of bZIP1, phytochrome B, and phytochrome C genes was enhanced even in 12-day-old Satabdi seedlings following instantaneous short-duration (2 h 30 min) controlled electromagnetic exposure to 1837.50 MHz, 2.75 W/m2 . The reported responses in rice were observed below the international electromagnetic regulatory limits. Thus, rice plants perceived electromagnetic energy emitted by the wireless communication system as abiotic stress as per its response by upregulation or repression of known stress-sensing genes. Bioelectromagnetics. © 2020 Bioelectromagnetics Society.
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Campos Eletromagnéticos/efeitos adversos , Oryza/fisiologia , Oryza/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Oryza/genética , Oryza/metabolismo , Plântula/genética , Plântula/efeitos da radiaçãoRESUMO
Electromagnetic energy is utilized over multiple frequency bands to provide seamless wireless communication services. Plants can well perceive electromagnetic energy present in open environment due to reasonably high permittivity and electrical conductivity of constituent tissues. Moreover, higher surface-to-volume ratio of plant structure facilitates increased interaction with the incident electromagnetic waves. To date, a few well-designed studies have been conducted inside controlled electromagnetic reverberation chambers to investigate either short duration-low amplitude or long duration-periodic electromagnetic irradiation-induced molecular responses in plants. However, as far as is known, studies investigating molecular responses particularly at the mid-vegetative stage in plants following one-time (hours-long) electromagnetic irradiation have not been reported earlier. Hence, the present study aimed at investigating molecular responses in 40-day-old Swarnaprabha rice plants following one-time 1837.50 MHz, 2.75 mW/m2 electromagnetic irradiation of 2 h 30 min duration. Controlled electromagnetic irradiation inside a simple reverberation chamber was ensured to achieve pure electromagnetic environment at 1837.50 MHz with deterministic electromagnetic power density at selected position. Swarnaprabha rice plant was chosen for this investigation since the rice variety is widely cultivated and consumed in the Indian subcontinent. Subsequent alterations in some selected stress-sensitive gene expressions were assayed using real-time quantitative polymerase chain reaction technique-significant upregulation in calmodulin and phytochrome B gene expressions were noted. This investigation was purposefully focused on subsequent molecular responses immediately following electromagnetic irradiation so that the possible effects of secondary stimulations could be avoided. Observed molecular responses strongly suggested that plants perceive 1837.50 MHz, 2.75 mW/m2 electromagnetic irradiation similar to other injurious stimuli. © 2021 Bioelectromagnetics Society.
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Oryza , Radiação Eletromagnética , Expressão Gênica , Oryza/genéticaRESUMO
PURPOSE: To review the literature regarding intraocular gas tamponade after vitrectomy for rhegmatogenous retinal detachment. METHODS: The history and evolution of the use of gas is described. The theories explaining gas tamponade are discussed, and efficacy and safety studies in human and animal models are covered. RESULTS: A total of 61 articles relating to gas tamponade were cited in this review. CONCLUSION: Gas tamponade is a frequently used procedure in vitreoretinal surgery. An understanding of its mechanism of action is crucial for its safe use when determining which gas is to be used and at what concentration.
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Tamponamento Interno/métodos , Fluorocarbonos/administração & dosagem , Complicações Pós-Operatórias/prevenção & controle , Descolamento Retiniano/cirurgia , Animais , Humanos , Vitrectomia/métodosRESUMO
The objective of the study was to carry-out batch tests to examine the effectiveness of Haix-Fe-Zr and Haix-Zr resin beads in the removal of As(III), As(V) and F- from groundwater with a similar geochemistry to a site where a community-based drinking water plant has been installed in West Bengal, India. The groundwater was spiked separately with â¼200⯵g/L As(III) and As(V) and 5â¯mg/L F-. Haix-Zr resin beads were more effective than Haix-Fe-Zr resin beads in removing As(III) and As(V). Haix-Zr resin beads showed higher removal of As(V) compared to As(III). Haix-Zr resin beads removed As(V) below the WHO (10⯵g/L) drinking water standards at 8.79⯵g/L after 4â¯h of shaking, while As(III) was reduced to 7.72⯵g/L after 8â¯h of shaking. Haix-Fe-Zr resin beads were more effective in removing F- from the spiked groundwater compared to Haix-Zr resin beads. Concentrations of F- decreased from 6.27â¯mg/L to 1.26â¯mg/L, which is below the WHO drinking water standards (1.5â¯mg/L) for F-, after 15â¯min of shaking with Haix-Fe-Zr resin beads. After 20â¯min of shaking in groundwater treated with Haix-Zr resin beads, F- concentrations decreased from 6.27â¯mg/L to 1.43â¯mg/L. In the removal of As(III), As(V), and F- from the groundwater, Haix-Fe-Zr and Haix-Zr resin beads fit the parabolic diffusion equation (PDE) suggesting that adsorption of these contaminants was consistent with inter-particle diffusion.
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Arsênio/isolamento & purificação , Água Potável , Fluoretos/isolamento & purificação , Purificação da Água , Adsorção , Água Subterrânea , Índia , Poluentes Químicos da ÁguaRESUMO
PURPOSE: Describe the clinical features and outcomes of patients with peripheral retinal vasculitis (RV) and describe clinical characteristics of presumed tubercular RV in a nonendemic setting. METHODS: Retrospective cohort study of 110 consecutive patients with peripheral RV at a tertiary referral eye care center in the United Kingdom. Retinal vasculitis was defined as RV with vitritis associated with peripheral retinal ischemia. Patients who also had positive Quantiferon Gold in Tube test, positive tuberculin skin test, and/or other evidence of systemic tuberculosis such as biopsy were labeled with presumed tubercular RV. Treatment success was defined as resolution of inflammation, and successful tapering of oral corticosteroids to less than 10 mg/day or topical steroids to less than twice a day. RESULTS: Mean age of the study population was 42.69 ± 14.95 years. Patients were predominantly Asian (49.1%) and Male (67.0%). A total of 73.2% had bilateral involvement. Sixty-nine (62.72%) patients had presumed tubercular RV. A total of 52.8% patients received antitubercular therapy, 65.5% received oral corticosteroids, and 17.3% required steroid-sparing oral immunosuppressive agents. A total of 85.19% of patients with presumed tubercular RV achieved treatment success with concurrent antitubercular therapy as against 75.61% of patients with nontubercular RV. CONCLUSION: This is the largest study of the epidemiology, clinical features, and outcomes of both peripheral RV and presumed tubercular RV to date. Presumed tubercular RV commonly seems to affect young males of Asian descent and had vitreous hemorrhage as common clinical findings and also demonstrated a good treatment outcome with antitubercular therapy.
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Corticosteroides/uso terapêutico , Imunossupressores/uso terapêutico , Vasculite Retiniana , Esteroides/uso terapêutico , Tuberculose Ocular/complicações , Adulto , Antituberculosos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vasculite Retiniana/tratamento farmacológico , Vasculite Retiniana/epidemiologia , Vasculite Retiniana/etiologia , Vasculite Retiniana/patologia , Estudos Retrospectivos , Tuberculose Ocular/tratamento farmacológico , Reino Unido/epidemiologia , Acuidade Visual , Adulto JovemRESUMO
BACKGROUND: To evaluate the contribution made to the diagnostic work-up for patients with suspected ocular tuberculosis (TB) by QuantiFERON-TB Gold In-Tube (QFT) tests using latent class analysis model. METHODS: A single centre retrospective cohort study. A Bayesian latent class model was constructed on the basis of demographics, phenotypes and test results from patients attending a tertiary referral center in the UK. This estimated the probability of ocular TB for each patient in two versions, first with and then without QFT. The estimated probability of ocular TB was compared with treatment failure. RESULTS: From a database of 365 patients with clinical signs suggestive of ocular TB, 267 patients who had QFT and complete data were evaluated. Mean age was 45.0 ± 15.4 years with 141 (52.9%) male and 148 (50.5%) of Asian ethnicity. QFT was positive in 208 (70.1%) patients and ATT was instituted in 145 (49.5%) patients with 100 (34.1%) patients also having concurrent systemic corticosteroid therapy. The best estimate of a QFT level separating TB-positive and TB-negative patients was extremely low. This weak discrimination between TB and non-TB groups was reflected in poor positive and negative predictive values for treatment failure. CONCLUSIONS: The latent class model did not successfully predict treatment failure, despite taking all variables into account. The threshold between TB and non-TB in QFT values was implausibly low and removing QFT from the model made prediction slightly worse. A larger prospective study is required to establish the role of all tests, demographics and phenotypes in diagnosis.
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Interferon gama/sangue , Tuberculose Ocular/diagnóstico , Adulto , Teorema de Bayes , Técnicas de Diagnóstico Oftalmológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Teste TuberculínicoRESUMO
Phosphate and colloidal gas aphrons (CGAs) generated from saponin extracted from Sapindus mukorossi fruit, were evaluated for washing low levels of arsenic from an iron rich soil. Phosphate is one of the most commonly dispersed chemicals that increases arsenic mobility in soil due to their structural similarities, making it an important factor in arsenic removal process. Column washing experiments were performed with CGAs in down flow and up flow modes on soil of pH 5 and 6. Soapnut CGAs, when paired with phosphate removed up to 95 % arsenic while soapnut CGAs alone could only remove up to 70 % arsenic. The presence of phosphate improved efficiency of soapnut solution by up to 35 %. SEM image of washed soil revealed minor corrosion of soil surface while using phosphate with soapnut. Therefore, the addition of phosphates would have positive impact on soil washing using soapnut saponin.
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Arsênio/análise , Recuperação e Remediação Ambiental/métodos , Microbolhas , Fosfatos/química , Sapindus/química , Solo/química , Suspensões/química , Saponinas/química , Poluentes do Solo/análiseRESUMO
Intorduction: Patients usually undergo orthodontic treatment for achieving ideal interocclusal relationship between the dental tissue and bony tissue along with improving the speech, mastication, and facial esthetic appearance. Literature quotes paucity in the studies evaluating the effect of orthodontic treatment on the periodontal health of endodontically treated teeth. Hence, we planned the present study to assess the effect of orthodontic treatment on the periodontal health of endodonti-cally restored tooth. MATERIALS AND METHODS: The present study included assessment of 80 patients who underwent orthodontic treatment. All the patients were divided broadly into two study groups: groups I and II. Group I included patients with the absence of endodontically treated teeth, while group II included patients which maxillary central incisors were resorted endodontically. Examination of the periodontal health of the patients was done using the community periodontal index of treatment need (CPITN) around the selected teeth. All the values were recorded during the preorthodontic time, postorthodontic time, and after the first 6 months of starting of the orthodontic treatment. All the results were recorded separately and analyzed. RESULTS: In the groups I and II, 28 and 25 patients respectively, had score of 1, while 10 patients in group I and 12 patients in group II had score of 2. Nonsignificant results were obtained while comparing the CPITN score in between the two study groups when measured at the pre-, intra-, and postortho time. CONCLUSION: In patients undergoing orthodontic treatment, having endodontically resorted teeth, no difference exists in relation to the periodontal health. CLINICAL SIGNIFICANCE: Orthodontic treatment can be safely carried in patients with endodontically restored teeth.