The digitally replicated denture technique: A case report.

OBJECTIVE: Conventional complete denture protocols require several patient appointments with multiple laboratory procedures. There are multiple workflows incorporating digital technology that can expedite the process, whereas increasing predictability. The proposed digitally replicated denture technique (DRDT) demonstrates a predictable workflow for fabricating complete dentures for patients with existing dentures. CLINICAL PROCEDURE: A patient's existing maxillary and mandibular complete dentures were scanned with an intraoral scanner. The generated STL was then printed using a desktop 3D printer. This served as a custom tray and record base to decrease patient chair time and associated laboratory procedures. CONCLUSION: The DRDT workflow incorporates digital technology into a complete denture protocol to minimize laboratory steps and chair time when fabricating complete dentures for patients with existing prostheses. CLINICAL SIGNIFICANCE: The use of a digitally replicated denture using rapid prototyping can streamline the process of complete denture fabrication for patients with existing dentures.

Composite Zn1-x Cd x GeAs2 semiconductors: structural and electrical properties.

We present the studies of structural, transport and magnetotransport properties of [Formula: see text]Cd x GeAs2 crystals with the chemical content changing from 0 to 1. The structural studies indicate that this alloy exists as a composite two-phase material in almost the entire range of average chemical compositions. The two phase nature of our samples does have a significant influence on the carrier transport and magnetotransport of the composite alloy. The change of the conductivity type is observed at room temperature, from p-type for [Formula: see text] to n-type for x > 0.18, respectively. The Hall carrier mobility measured at room temperature decreases as a function of x from about 35 cm2 (V · s)-1 for the sample with x = 0 down to 3 cm2 (V · s)-1 for the sample with x = 0.233. For x > 0.233 the Hall carrier mobility shows an increase with x, up to the highest value around 875 cm2 (V · s)-1 observed for the sample with x = 1. Temperature dependent resistivity measurements indicate the presence of thermal activation of carriers with activation energy, E a, with values from 20 to 30 meV for all the studied samples. The temperature dependent Hall effect data show that the grain boundary limited transport is strong in all our samples. For the samples with [Formula: see text] the negative MR is observed at temperatures lower than 100 K and at low magnetic field values, [Formula: see text] T. This effect is interpreted as a weak localization phenomenon with low values of phase coherence length, [Formula: see text] nm.

Direct observation and temperature control of the surface Dirac gap in a topological crystalline insulator.

Since the advent of topological insulators hosting Dirac surface states, efforts have been made to gap these states in a controllable way. A new route to accomplish this was opened up by the discovery of topological crystalline insulators where the topological states are protected by crystal symmetries and thus prone to gap formation by structural changes of the lattice. Here we show a temperature-driven gap opening in Dirac surface states within the topological crystalline insulator phase in (Pb,Sn)Se. By using angle-resolved photoelectron spectroscopy, the gap formation and mass acquisition is studied as a function of composition and temperature. The resulting observations lead to the addition of a temperature- and composition-dependent boundary between massless and massive Dirac states in the topological phase diagram for (Pb,Sn)Se (001). Overall, our results experimentally establish the possibility to tune between massless and massive topological states on the surface of a topological system.

Topological crystalline insulator states in Pb(1-x)Sn(x)Se.

Topological insulators are a class of quantum materials in which time-reversal symmetry, relativistic effects and an inverted band structure result in the occurrence of electronic metallic states on the surfaces of insulating bulk crystals. These helical states exhibit a Dirac-like energy dispersion across the bulk bandgap, and they are topologically protected. Recent theoretical results have suggested the existence of topological crystalline insulators (TCIs), a class of topological insulators in which crystalline symmetry replaces the role of time-reversal symmetry in ensuring topological protection. In this study we show that the narrow-gap semiconductor Pb(1-x)Sn(x)Se is a TCI for x = 0.23. Temperature-dependent angle-resolved photoelectron spectroscopy demonstrates that the material undergoes a temperature-driven topological phase transition from a trivial insulator to a TCI. These experimental findings add a new class to the family of topological insulators, and we anticipate that they will lead to a considerable body of further research as well as detailed studies of topological phase transitions.

Stevens-Johnson syndrome associated with carvedilol therapy.

Stevens-Johnson syndrome, related to carvedilol use, has not been previously reported as a serious adverse experience requiring hospitalization. We report this reaction in a 71-year-old man with stable ischemic cardiomyopathy.