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Introduction: Early diagnosis combined with conservative adhesive treatment of occlusal caries may preserve the integrity of the remaining tooth and increase its longevity. Aim: To compare microleakage and Shear Bond Strength (SBS) of Dyad flow and Tetric flow in primary molars. Materials and Methods: Microleakage test: Eighteen samples were utilised separately for SBS and Microleakage. Standard Class I tooth cavity were prepared on occlusal surface of all teeth. The samples of Group 1 group were restored with Dyad flow restorative material; Samples of Group 2 were restored with Tetric flow and subjected to thermocycling in customized thermocycling device. Further, the samples were soaked in freshly prepared 2% Rhodamine B dye solution for 24 hours. The samples were then sectioned in bucco-lingual direction with hard tissue microtome under constant water flow and were observed under confocal microscope at 4× magnification and evaluated for die penetration. Eight out of nine samples were graded III, where as the other sample was graded as II based on ISO microleakage scoring system. Shear Bond Strength Test: A 2 mm high cylindrical polyethylene tube with an internal diameter of approximately 2 mm was placed on the dentin surface of each specimen. No etching or bonding was done for samples of Group 1 (Dyad flow), Optibond bonding agent was applied to the prepared buccal surface of the specimens in group 2 (Tetric Flow) and cured for 20 seconds. Flowable resin composite was injected into the tube and polymerized for 40 seconds using an LED curing unit. All specimens were subjected to thermocycling from 5°C and 55°C for 500 cycles. SBS testing was done following thermocycling. Specimens were secured in the holder of a universal testing machine and sheared with a knife-edge blade at a crosshead speed of 1.0 mm/minute. Independent t-test was performed for statistical significance. Results: Microleakage Test: There was no significant difference in microleakage between Dyad Flow and Tetric flow (p

Any disturbance in the primary tooth can lead to an altered eruption pattern of the corresponding permanent tooth. This article presents a case of a carious permanent second premolar with an immature root that erupted prematurely following extraction of the infected primary second molar. The carious premolar was treated with a stepwise excavation, and a primary stainless steel crown was adapted to prevent microleakage and restoration failure. A follow-up evaluation at 4 years showed remarkable healing and complete root formation. To the authors' knowledge, this is the first case report in the literature that describes successful conservative management of a rootless premolar treated by pulp capping and restored with a primary stainless steel crown.

We use resonant and non-resonant X-ray diffraction measurements in combination with first-principles electronic structure calculations and Monte Carlo simulations to study the relationship between crystal structure and multiferroic orders in the orthorhombic perovskite manganites, o-$R$MnO$_3$ ($R$ is a rare-earth cation or Y). In particular, we focus on how the internal lattice parameters (Mn-O bond lengths and Mn-O-Mn bond angles) evolve under chemical pressure and epitaxial strain, and the effect of these structural variations on the microscopic exchange interactions and long-range magnetic order. We show that chemical pressure and epitaxial strain are accommodated differently by the crystal lattice of o-$R$MnO$_3$, which is key for understanding the difference in magnetic properties between bulk samples and strained films. Finally, we discuss the effects of these differences in the magnetism on the electric polarization in o-$R$MnO$_3$., Comment: 16 pages, 10 figures

X-ray magnetic circular dichroism (XMCD) and x-ray magnetic linear dichroism (XMLD) have been used to investigate the Fe magnetic response during the spin-reorientation transition (SRT) in $\mathrm{TmFe}{\mathrm{O}}_{3}$. Comparing the Fe XMLD results with neutron-diffraction and magnetization measurements on the same sample indicates that the SRT has an enhanced temperature range in the near surface region of approximately 82 to 120 K compared to approximately 82 to 92 K in bulk. This view is supported by complementary resonant soft x-ray-diffraction experiments at the Tm ${M}_{5}$ edge. These measurements find an induced magnetic moment on the Tm sites, which is well described by a dipolar mean-field model originating from the Fe moments. Even though such a model can describe the $4f$ response in the experiments, it is insufficient to describe the SRT even when considering a change in the $4f$ anisotropy. Moreover, the results of the Fe XMCD show a different temperature evolution through the SRT, the interpretation of which is hampered by additional spectral shape changes of the XCMD signal.

Using resonant soft x-ray techniques we follow the magnetic behavior of a strained epitaxial film of $\mathrm{CoC}{\mathrm{r}}_{2}{\mathrm{O}}_{4}$, a type-II multiferroic. The film is [110] oriented, such that both the ferroelectric and ferromagnetic moments can coexist in-plane. X-ray magnetic circular dichroism (XMCD) is used in scattering and in transmission modes to probe the magnetization of Co and Cr separately. The transmission measurements utilized x-ray excited optical luminescence from the substrate. Resonant soft x-ray diffraction (RXD) was used to study the magnetic order of the low temperature phase. The XMCD signals of Co and Cr appear at the same ordering temperature ${T}_{C}\ensuremath{\approx}90\phantom{\rule{4pt}{0ex}}\mathrm{K}$, and are always opposite in sign. The coercive field of the Co and of Cr moments is the same, and is approximately two orders of magnitude higher than in bulk. Through sum rules analysis an enlarged $\mathrm{C}{\mathrm{o}}^{2+}$ orbital moment (${m}_{L}$) is found, which can explain this hardening. The RXD signal of the (q q 0) reflection appears below ${T}_{S}$, the same ordering temperature as the conical magnetic structure in bulk, indicating that this phase remains multiferroic under strain. To describe the azimuthal dependence of this reflection, a slight modification is required to the spin model proposed by the conventional Lyons-Kaplan-Dwight-Menyuk theory for magnetic spinels.

Chiral multiferroic langasites have attracted attention due to their doubly chiral magnetic ground state within an enantiomorphic crystal. We report on a detailed resonant soft x-ray diffraction study of the multiferroic ${\mathrm{Ba}}_{3}{\mathrm{TaFe}}_{3}{\mathrm{Si}}_{2}{\mathrm{O}}_{14}$ at the Fe ${L}_{2,3}$ and oxygen $K$ edges. Below ${T}_{N}$ ($\ensuremath{\approx}27K$) we observe the satellite reflections $(0,0,\ensuremath{\tau}), (0,0,2\ensuremath{\tau}), (0,0,3\ensuremath{\tau})$, and $(0,0,1\ensuremath{-}3\ensuremath{\tau})$ where $\ensuremath{\tau}\ensuremath{\approx}0.140\ifmmode\pm\else\textpm\fi{}0.001$. The dependence of the scattering intensity on x-ray polarization and azimuthal angle indicate that the odd harmonics are dominated by the out-of-plane ($\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\mathbf{c}}$ axis) magnetic dipole while the $(0,0,2\ensuremath{\tau})$ originates from the electron density distortions accompanying magnetic order. We observe dissimilar energy dependencies of the diffraction intensity of the purely magnetic odd-harmonic satellites at the Fe ${L}_{3}$ edge. Utilizing first-principles calculations, we show that this is a consequence of the loss of threefold crystal symmetry in the multiferroic phase.

We investigate the demagnetization dynamics of the cycloidal and sinusoidal phases of multiferroic TbMnO3 by means of time-resolved resonant soft x-ray diffraction following excitation by an optical pump. The use of orthogonal linear x-ray polarizations provides information on the contribution from the different magnetic moment directions, which can be interpreted as signatures from multiferroic cycloidal spin order and sinusoidal spin order. Tracking these signatures in the time domain enables us to identify the transient magnetic phase created by intense photoexcitation of the electrons and subsequent heating of the spin system on a picosecond time scale. The transient phase is shown to exhibit mostly spin density wave character, as in the adiabatic case, while nevertheless retaining the wave vector of the cycloidal long-range order. Two different pump photon energies, 1.55 and 3.1 eV, lead to population of the conduction band predominantly via intersite d-d or intrasite p-d transitions, respectively. We find that the nature of the optical excitation does not play an important role in determining the dynamics of magnetic order melting. Further, we observe that the orbital reconstruction, which is induced by the spin ordering, disappears on a time scale comparable to that of the cycloidal order, attesting to a direct coupling between magnetic order and orbital reconstruction. Our observations are discussed in the context of recent theoretical models of demagnetization dynamics in strongly correlated systems, revealing the potential of this type of measurement as a benchmark for such theoretical studies.

Deciphering the relative importance of genetic and environmental factors, which play a major role in the prevalence of early childhood caries (ECC), can help clinicians with planning a long-term preventive treatment. The objective of the study was to determine the prevalence and heritability of ECC among monozygotic (MZ) and dizygotic (DZ) twins in Chennai, India, in the year 2013. A cross-sectional study was designed to estimate the prevalence of ECC among twins. Zygosity classification for the survey framework was adapted from a highly accurate parental report questionnaire pertaining to the physical similarity between twins. The associated heritability index was estimated. The Decayed, Missing, Filled Surface (DMFS) Index was used as the diagnostic criterion for dental caries. The prevalence of ECC was estimated at 18.7%. The correlation coefficient between the twin pair showed significant correlation. The heritability index for ECC was estimated at 15% higher prevalence of ECC found among children in the age group 25–36 months. The heritability estimate indicated a relatively low genetic influence for early childhood caries among twins. There was no significant difference detected in the concordance rate for the MZ and DZ twins. Further research could be directed toward the prevalence of ECC among higher age group children to explore the role of genetic and environmental factors.

Cerebral palsy (CP) is described as a group of permanent, nonprogressive movement disorders that cause physical disability in development and further affecting body movement and muscle coordination. The condition develops when certain abnormalities persist inside the developing brain that ultimately disrupts the brain's ability to control movement and maintain posture and balance. Patients with CP are more susceptible to dental trauma due to the lack of muscle coordination and unexpected involuntary movements. The present case series highlights the need for emergency protocol management when these patients report with dental trauma and complications which can happen in dental office. The first case report is about ingestion of permanent incisor following trauma which was diagnosed incidentally in the abdominal radiograph, and the second case is reported to be accidental ingestion of head of dental mouth mirror during the routine oral examination. These two case reports emphasize the need for more comprehensive trauma management protocol in these children.

Cotton farmers in many developing countries are facing decreasing marginal returns due to stagnating yields and high input costs. Conversion to organic management could offer an alternative. In a two year comparative study in central India covering 170 cotton fields, organic farms achieved cotton yields that were on par with those in conventional farms, whereby nutrient inputs and input costs per crop unit were reduced by half. Due to 10–20% lower total production costs and a 20% organic price premium, average gross margins from organic cotton fields were 30–40% higher than in the conventional system. Although the crops grown in rotation with cotton were sold without premium, organic farms achieved 10–20% higher incomes from agriculture. In addition to these economic benefits, the organic farming system does not burden soil and groundwater with synthetic fertilizers and pesticides. However, in this study only minor differences were detected in soil fertility parameters of organic and conventional fields. Altogether, the results suggest that conversion to organic farming can improve livelihoods of smallholders while protecting natural resources. Income loss due to reduced yields in initial years of transition, however, constitutes a major hurdle, especially for poorer farmers. It is thus important to support farmers in overcoming the obstacles of the conversion period.

We investigated the crystal structure and lattice excitations of the ternary intermetallic stannide Ca3Ir4Sn13 using neutron and x-ray scattering techniques. For T > T* ~ 38 K the x-ray diffraction data can be satisfactorily refined using the space group Pm-3n. Below T* the crystal structure is modulated with a propagation vector of q = (1/2, 1/2, 0). This may arise from a merohedral twinning in which three tetragonal domains overlap to mimic a higher symmetry, or from a doubling of the cubic unit cell. Neutron diffraction and neutron spectroscopy results show that the structural transition at T* is of a second-order, and that it is well described by mean-field theory. Inelastic neutron scattering data point towards a displacive structural transition at T* arising from the softening of a low-energy phonon mode with an energy gap of Delta(120 K) = 1.05 meV. Using density functional theory the soft phonon mode is identified as a 'breathing' mode of the Sn12 icosahedra and is consistent with the thermal ellipsoids of the Sn2 atoms found by single crystal diffraction data.

Endodontic management of the geminated tooth requires a proper understanding of root canal morphology. The use of cone beam computed tomography (CBCT) in the diagnosis of complex endodontic morphology, and in revealing morphological variations, has been well documented in the literature. A case involving endodontic management of a geminated primary central incisor with CBCT is presented here. A CBCT analysis was vital in the diagnosis of this unusual root canal system and its successful endodontic treatment.

Using the small angle neutron scattering (SANS) technique we investigated the vortex lattice (VL) in the mixed state of the stannide superconductor Yb$_{3}$Rh$_{4}$Sn$_{13}$. We find a single domain VL of slightly distorted hexagonal geometry for field strengths between 350 and 18500 G and temperatures between T = 0.05 and T = 6.5 K. We observe a clear in-plane rotation of the VL for different magnetic field directions relative to the crystallographic axes. We also find that the hexagonal symmetry of the VL is energetically favorable in Yb$_{3}$Rh$_{4}$Sn$_{13}$ for external fields oriented along axes of different symmetries: twofold [110], threefold [111] and fourfold [100]. The observed behavior is different from other conventional and unconventional superconductors. The superconducting state is characterized by an isotropic gapped order parameter with an amplitude of $\Delta(0)$ = 1.57 $\pm$ 0.05 meV. At the lowest temperatures the field dependence of the magnetic form factor in our material reveals a London penetration depth of $\lambda_{L}$ = 2508 $\pm$ 17 $\AA$ and a Ginzburg coherence length of $\xi$ = 100 $\pm$ 1.3 $\AA$, i.e., it is a strongly type-II superconductor, $\kappa$ = $\lambda_{L}/\xi$ = 25.

The vortex lattice (VL) in the mixed state of the stannide superconductor Yb$_{3}$Rh$_{4}$Sn$_{13}$ has been studied using small-angle neutron scattering (SANS). The field dependencies of the normalized longitudinal and transverse correlation lengths of the VL, $\xi_L/a_0$ and $\xi_T /a_0$, reveal two distinct anomalies that are associated with vortex-glass phases below $\mu_0H_l$~$\approx$~700~G and above $\mu_{0}H_h$~$\sim$~1.7~T ($a_0$ is the intervortex distance). At high fields, around 1.7~T, the longitudinal correlation decreases abruptly with increasing fields indicating a weakening (but not a complete destruction) of the VL due to a phase transition into a glassy phase, below $\mu_{0}H_{c_2}$(1.8 K)~$\approx$~2.5~T. $\xi_L/a_0$ and $\xi_T /a_0$, gradually decrease for decreasing fields of strengths less than 1~T and tend towards zero. The shear elastic modulus $c_{66}$ and the tilting elastic modulus $c_{44}$ vanish at a critical field $\mu_0H_l$~$\approx$~700~G, providing evidence for a disorder-induced transition into a vortex-glass. A 'ring' of scattered intensity is observed for fields lower than 700~G, $i.e.$, $\mu_{0}H_{c_1}$~=~135~G~$

The treatment of early childhood caries can have a significant economical burden and treatment relapses are frequent. Effective intervention by means of topical antimicrobial agents can reduce the burden of early childhood caries. The main aim in prevention and treatment should focus on inhibition of the growth of oral bacteria. This is a comprehensive review of the literature on the various antimicrobial agents which are proven to be effective in management of this carious progression. The review identified that there is a significant data to suggest use of antimicrobial agents in management of early childhood caries. Antimicrobial agents aid in better management of patients with early carious lesion. The relapse rates are less, when the treatment is combined with the use of antimicrobial agent.

Multiferroic properties of orthorhombic HoMnO3 (Pbnm space group) are significantly modified by epitaxial compressive strain along the a-axis. We are able to focus on the effect of strain solely along the a-axis by using an YAlO3 (010) substrate, which has only a small lattice mismatch with HoMnO3 along the other in-plane direction (the c-axis). Multiferroic properties of strained and relaxed HoMnO3 thin films are compared with those reported for bulk, and are found to differ widely. A relaxed film exhibits bulk-like properties such as a ferroelectric transition temperature of 25 K and an incommensurate antiferromagnetic order below 39 K, with an ordering wave vector of (0 qb 0) with qb ~ 0.41 at 10 K. A strained film becomes ferroelectric already at 37.5 K and has an incommensurate magnetic order with qb ~ 0.49 at 10 K., submitted to Applied Physics Letters

We performed ultrafast time resolved near infrared pump resonant soft x ray diffraction probe measurements to investigate the coupling between the photoexcited electronic system and the spin cycloid magnetic order in multiferroic TbMnO3 at low temperatures. We observe melting of the long range antiferromagnetic order at low excitation fluences with a decay time constant of 22.3 ± 1.1 ps which is much slower than the ~1 ps melting times previously observed in other systems. To explain the data we propose a simple model of the melting process where the pump laser pulse directly excites the electronic system which then leads to an increase in the effective temperature of the spin system via a slower relaxation mechanism. Despite this apparent increase in the effective spin temperature we do not observe changes in the wave vector q of the antiferromagnetic spin order that would typically correlate with an increase in temperature under equilibrium conditions.We suggest that this behavior results from the extremely low magnon group velocity that hinders a change in the spin spiral wave vector on these time scales. DOI: 10.1103/PhysRevB.92.184429

The correlation between electronic and crystal structures of 1T-TiSe2 in the charge density wave (CDW) state is studied by x-ray diffraction. Three families of reflections are used to probe atomic displacements and the orbital asymmetry in Se. Two distinct onset temperatures are found, TCDW and a lower T* indicative for an onset of Se out-of-plane atomic displacements. T* coincides with a DC resistivity maximum and the onset of the proposed gyrotropic electronic structure. However, no indication for chirality is found. The relation between the atomic displacements and the transport properties is discussed in terms of Ti 3d and Se 4p states that only weakly couple to the CDW order., Comment: 16 pages, 4 figures + 13 pages supplementary info