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Objectives: To illustrate the characteristic features of odontogenic myxoma (OM) on CBCT. Methods: From 52 subjects with histopathologically diagnosed OMs, 18 subjects who underwent a CBCT examination were retrieved between May 2009 and April 2016. Features on CBCT images and clinical records were carefully observed and analyzed. Results: Characteristic features include: (1) fine and straight septa that were recognized to separate the tumour into triangular, square or rectangular spaces, which appeared as "tennis racket" or "honeycomb" patterns; (2) septa that frequently scattered to the borders of lesions and appeared perpendicular to the margins; (3) tooth displacement and resorption that were seen in most of the OM lesions; (4) OMs that were noted to have a tendency to involve the alveolar process, scallop between the roots and affect the integrity of the alveolar ridge; (5) the cortex of OMs that appeared normally perforated and the edge of the cortex expanded into the soft tissue. Conclusions: CBCT is highly effective in demonstrating the comprehensive internal structures of the lesions precisely and providing detailed information for the diagnosis of OM.

Strong bone-like nanocomposites of collagen type I and hydroxyapatite were prepared by coupling the in situ synthesis, hybrid gel formation and subsequent dehydration consolidation. The calcium phosphate synthesis was initiated at 4uC in the concentrated collagen monomeric solutions. Under this condition collagen molecules inhibited the calcium phosphate uncontrollably rapid growth and the predominant collagen fibril aggregation was retarded. Elevating temperature induced collagen fibrillogenesis leading to the formation of elastic hybrid gels. The dehydration consolidation of the elastic gels gave rise to strong nanocomposites. The mechanical properties and bone-like characteristics of the prepared nanocomposites were explicated. The in situ formation of a hybrid gel together with its facile processing capability suggests the versatility of this biomimetic strategy either in fabricating different structural forms (films, scaffolds and monoliths) of bone grafts or in further inclusion of other biosubstance into the nanocomposites.

The effects of ionizing radiation on materials often reduce to "bad news". Radiation damage usually leads to detrimental effects such as embrittlement, accelerated creep, phase instability, and radiation-altered corrosion. Here we report that proton irradiation decelerates intergranular corrosion of Ni-Cr alloys in molten fluoride salt at 650°C. We demonstrate this by showing that the depth of intergranular voids resulting from Cr leaching into the salt is reduced by proton irradiation alone. Interstitial defects generated from irradiation enhance diffusion, more rapidly replenishing corrosion-injected vacancies with alloy constituents, thus playing the crucial role in decelerating corrosion. Our results show that irradiation can have a positive impact on materials performance, challenging our view that radiation damage usually results in negative effects.

Hastelloy N Ò , a nickel-based alloy, and 316 stainless steel are among the candidate structural materials being considered for the construction of the molten salt reactor (MSR). Most of the proposed MSR concepts use molten fluoride salts as coolant which can be quite corrosive to structural alloys. The results of studies on the corrosion behavior of the two alloys in molten Li 2 BeF 4 (FLiBe) salt at 700°C are discussed. This salt is being considered as the primary coolant for MSR designs featuring solid fuel particles, but the reported results also provide insights into the corrosion in MSR designs where the uranium fuel is dissolved in the molten fluoride salt. Corrosion was observed to occur predominantly by de-alloying of Cr from the alloy surface and into the molten salt, with more pronounced attack occurring along the grain boundaries than in the bulk grains. The magnitude and the mechanisms of corrosion were different for corrosion tests performed in graphite and metallic capsules, a result warranting recognition given the coexistence of structural alloys and graphite in the molten salt medium in the MSR.