Evaluation of the Functional Impression Technique with Various Impression Materials on the Surface Topography of Dental Stone Casts and Their Effect on Retention

Background: The accuracy of the final prosthesis is affected by the final impression technique and master cast production. The aim of the present study was to evaluate the effect of the functional impression technique with various impression materials on the surface characteristic of dental stone casts and their clinical effect on the retention of complete dentures. Method: Specimens of three impression materials/stone casts were fabricated. The specimens of the impression materials/stone casts were divided into three equal groups (I, II, and III). The impression materials used were as follows: tissue conditioner group (I), zinc oxide (ZEO) (group II) and poly (vinyl siloxane) (PVS) (group III). Cylindrical split aluminium moulds were designed to receive the impression materials and the stone mixture. The surface roughness of the stone cast specimens of the three groups (I, II, and III) was measured with a surface profilometer and analyzed by a scanning electron microscope. A clinical study included five severely resorbed mandibular edentulous alveolar ridges and edentulous maxillary arches. Each subject received three heat-cured acrylic resin dentures, fabricated using the functional impression technique. The three dentures were identical except for the different impression materials used from Groups I, II and III. The retentive force of each denture for each subject was measured. Result: The results of this study revealed that the mean value of surface roughness of the stone cast surface of group I was higher than group II and group III. A statistically significant difference was observed in surface roughness and the retentive dislodging force between the three studied groups. Although using a tissue conditioner as a functional impression material led to a high level of surface roughness and good retention, it could not produce the same smooth surface quality of PVS or ZEO. These data were supported by SEM analysis. The complete dentures for these patients require important oral and denture hygiene care. Conclusion: Complete dentures made using functional impression technique with PVC as a final impression material are more comfortable, retentive and stable.

Use of graphene nanocomposites for air disinfection in dental clinics:A game-changer in infection control

This manuscript features the promising findings of a study conducted by Ju et al,who used graphene nanocomposites for air disinfection in dental clinics.Their study demonstrated that,compared with conventional filters,graphene nanocom-posites substantially improved air quality and reduced microbial contamination.This manuscript highlights the innovative application of graphene materials,emphasizing their potential to enhance dental clinic environments by minimizing secondary pollution.On the basis of the unique antimicrobial properties of gra-phene and the original study’s rigorous methodology,we recommend using gra-phene nanocomposites in clinical settings to control airborne infections.

Literary Impressionism in Willa Cather's Novels

In her writing,Willa Cather absorbed the techniques of the impressionist painters,striving to present human perception and fo-cus their individual impression on a fleeting moment to provide the fragments of impression upon which the whole can be constructed.

Conjunctival impression cytology in non-proliferative and proliferative diabetic retinopathy

AIMTo examine the integrity of the ocular surfaces of subjects with and without diabetes with no conjunctival and dry eye signs and symptoms and compare conjunctival impression cytology findings in diabetics with non-proliferative and proliferative diabetic retinopathy.

Effect of Ca addition on microstructure and impression creep behavior of cast AZ61 magnesium alloy

Microstructure and creep properties of AZ61 alloy containing 1 and 3 wt.% Ca were investigated. The creep properties were examined using impression method under different stresses between 200 and 500 MPa at the temperature ranging from 423 to 491 K. The microstructure of AZ61 alloy contains α(Mg) matrix and Mg17 Al12 intermetallic phases. It is shown that adding Ca to AZ61 alloy reduces the amount of Mg17 Al12 phase via forming(Mg,Al)2 Ca phase;furthermore, increasing the Ca content to 3 wt.% leads to the formation of(Mg,Al)2 Ca phase, as well as the elimination of the Mg17 Al12 phase. Creep properties of AZ61 alloy are improved with the Ca addition. The improvement in creep properties is attributed to the reduction in the amount of Mg17 Al12 phase and the formation of(Mg,Al)2 Ca phase with high thermal stability. According to the obtained creep data, it is concluded that the pipe diffusion-climb controlled dislocation creep is the dominant creep mechanism and Ca addition has no influence on this mechanism. The effect of pre-deformation on the creep properties of AZ61+3%Ca alloy reveals that the creep resistance of the alloy depends on the continuity of(Mg,Al)2 Ca phase. It is decreased by reducing the phase continuity.

Effect of Mg and semi solid processing on microstructure and impression creep properties of A356 alloy

The effects of Mg and semi solid processing on the creep properties ofA356 A1 alloy were investigated. The results show that the dislocation climb controlled creep is the dominant creep mechanism and it is not affected by the semi solid processing and further addition of Mg. Mg improves the alloy creep properties probably by forming large Chinese script Mg2Si compounds at the interdendritic regions. The semi solid processed specimens exhibit better creep properties in comparison with the as cast ones. It is attributed to the reduction in the stacking fault energy resulting from the significant dissolution of Mg in the a（A1） phase.

Ocular Surface Characteristics and Impression Cytology in Patients with Active versus Inactive Thyroid Eye Disease

Purpose:To compare the clinical findings, tear film function and impression cytology between patients with active and inactive Thyroid Eye Disease (TED). Methods:.A total of 56 patients with TED and 30 controls were recruited in this prospective observational cohort study. TED patients were divided into active TED and inactive TED types according to a seven-point modified formulation of the Clinical Activity Score (CAS). All participants underwent full eye examinations including Ocular Surface Disease Index (OSDI) score, tear film break-up time (TBUT), fluorescein staining and Schirmer I test. Thirty nine patients with thyroid-associated orbitopathy.(TAO) received Nelson's grade with conjunctival impression cytology. Proptosis, palpebral fissure width and lagophthalmos were assessed. Results:.Ocular surface parameters including proptosis, palpebral fissure width and lagophthalmos did not differ between active and inactive TED patients(P>0.05). Both active and inactive TED patients obtained higher fluorescein staining scores, lower TBUT scores and significantly lower Schirmer test scores than those of controls (P<0.001 for all). Additionally, the TBUT score was significantly lower and the OSDI score significantly higher in the active TED group compared with those in the inactive TED group (P<0.001 for both). Impression cytology revealed a higher proportion of grade 2-3 changes in the active TED group compared with the inactive TED group(P<0.001). Conclusion:.Orbital inflammation in TED patients may lead to decreased tear film stability and ocular surface squamous metaplasia.

SRIM Scheme： An Impression-Management Scheme for Privacy-Aware Photo-Sharing Users

With the development of online social networks （OSNs） and modern smartphones, sharing photos with friends has become one of the most popular social activities. Since people usually prefer to give others a positive impression, impression management during photo sharing is becoming increasingly important. However, most of the existing privacy-aware solutions have two main drawbacks： Users must decide manually whether to share each photo with others or not, in order to build the desired impression; and users run a high risk of leaking sensitive relational information in group photos during photo sharing, such as their position as part of a couple, or their sexual identity. In this paper, we propose a social rela- tion impression-management （SRIM） scheme to protect relational privacy and to automatically recom- mend an appropriate photo-sharing policy to users. To be more specific, we have designed a lightweight face-distance measurement that calculates the distances between users＇ faces within group photos by relying on photo metadata and face-detection results. These distances are then transformed into relations using proxemics. Furthermore, we propose a relation impression evaluation algorithm to evaluate and manage relational impressions. We developed a prototype and employed 21 volunteers to verify the functionalities of the SRIM scheme. The evaluation results show the effectiveness and efficiency of our proposed scheme.

测评一款LED灯具——GLP Impression X4 Bar 20

通过对Impression X4 Bar 20的测试,解析该LED灯具的构成、功能及其性能和特点。

A POTENTIAL METHOD FOR DETERMINING THE HAZ PROPERTIES IN WELDS USING TWO-MATERIAL IMPRESSION CREEP TEST

The results of a theoretical and finite element (FE) investigation of a two-material impression creep test method, using a rectangular indenter, are presented. The method uses a general formulation for steady-state creep deformation for multi-material components in conjunction with the results of FE analyses. The practical application of the proposed technique, in determining the secondary creep properties of heat-affected zone (HAZ) materials in welds, for which conventional creep testing methods cannot be used, is considered. A number of numerical examples are used to describe solution procedures and to verify the method.

Avoiding impression tears in gingival embrasures of anterior preparations

As restorative dentists, we are faced everyday with decisions about which impression materials and techniques should be used when restoring teeth. The challenge becomes bigger when the patients present with open gingival embrasures, the dreaded “black triangles”, which tops the list of dentist frustration while taking the impression and after preparation of veneers, crowns, bridges, etc. The technique described offers an option to avoid problems related to impressions locking in gingival embrasures and tearing on removal.

Impressions of Hazmat Suits Based on Color

Background: Commonly, skin and clothing surface contamination screening (radiation survey) is performed for residents of an area to confirm the levels of residual contamination after nuclear power disasters. Examiners for such a screening often wear white radiation hazmat suits. However, it has been reported that examinees tend to feel tension or anxiety. In this study, we focus on the color of the radiation hazmat suit as one measure to reduce residents’ tension or anxiety. This study aims to determine the common conceptions of radiation hazmat suits based on color. Methods: An anonymous self-administered questionnaire survey was conducted with a total of 262 participants consisting of nursing students, administrative staff of a university, general citizens, and mothers raising their children in the Tohoku region in Japan. The common impressions of radiation hazmat suits, which are typically white, were measured using the Multiple Affective States Scale. This scale can measure the affective state brought about by clothing. The color of white (W) was defined as a standard color commonly used for hazmat suits;in order to determine the common impressions of radiation hazmat suits based on color, the following additional colors were shown to the participants: salmon pink (P), ivory (I), and light green (G). Results: There were no sex differences regarding common impressions of radiation hazmat suits. For white radiation hazmat suits, a high score reflecting the characteristic of “capable” was obtained, while the scores for “cheerful” and “calm” were low, and those for “depressed” and “tense” were high. The colors that showed the highest score for “calm” as a positive affirmative state were I and P. W and P reflected a high “ashamed” score, and the “tense” score for G was higher for the participants in their 20s than for those in their 30s and older. Conclusions: Results show that the color of hazmat suits provokes far greater feelings of anxiety and tension on participants than previously thought. Radiation hazmat suits may be further improved based on the results of this study.

Impression Remolding: On Design of Lijiang Railway Station

This paper takes "impression remolding" as the hint of design concept, analyzes uniqueness and correlation of Lijiang Train Station, and also multiple design techniques of integrating regional cultural elements, such as roofi ng cluster.

Perception of dental appearance and aesthetic analysis among patients,laypersons and dentists

BACKGROUND Current concepts of beauty are increasingly subjective,influenced by the viewpoints of others.The aim of the study was to evaluate divergences in the perception of dental appearance and smile esthetics among patients,laypersons and dental practitioners.The study goals were to evaluate the influence of age,sex,education and dental specialty on the participants’judgment and to identify the values of different esthetic criteria.Patients sample included 50 patients who responded to a dental appearance questionnaire(DAQ).Two frontal photographs were taken,one during a smile and one with retracted lips.Laypersons and dentists were asked to evaluate both photographs using a Linear Scale from(0-10),where 0 represent(absolutely unaesthetic)and 10 represent(absolutely aesthetic).One-way analysis of variance(ANOVA)and t-test analysis were measured for each group.Most patients in the sample expressed satisfaction with most aspects of their smiles and dental appearance.Among laypersons(including 488 participants),47 pictures“with lips”out of 50 had higher mean aesthetic scores compared to pictures“without lips”.Among the dentist sample,90 dentists’perception towards the esthetic smile and dental appearance for photos“with lips”and“without lips”were the same for 23 out of 50 patients.Perception of smile aesthetics differed between patients,laypersons and dentists.Several factors can contribute to shape the perception of smile aesthetic.AIM To compare the perception of dental aesthetic among patients,laypersons,and professional dentists,to evaluate the impact of age,sex,educational background,and income on the judgments made by laypersons,to assess the variations in experience,specialty,age,and sex on professional dentists’judgment,and to evaluate the role of lips,skin shade and tooth shade in different participants’judgments.METHODS Patients sample included 50 patients who responded to DAQ.Two frontal photographs were taken:one during a smile and one with retracted lips.Laypersons and dentists were asked to evaluate both photographs using a Linear Scale from(0-10),where 0 represent(absolutely unaesthetic)and 10 represent(absolutely aesthetic).One-way ANOVA and t-test analysis were measured for each group.RESULTS Most patients in the sample expressed satisfaction with most aspects of their smiles and dental appearance.Among laypersons(including 488 participants),47 pictures“with lips”out of 50 had higher mean aesthetic scores compared to pictures“without lips”.Whereas among the dentist sample,90 dentists’perception towards the esthetic smile and dental appearance for photos“with lips”and“without lips”were the same for 23 out of 50 patients.Perception of smile aesthetics differed between patients,laypersons and dentists.CONCLUSION Several factors can contribute to shape the perception of smile aesthetic.

Conditioned medium from human dental pulp stem cells treats spinal cord injury by inhibiting microglial pyroptosis

Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery after spinal cord injury remains unclear.In the present study,we established a rat model of spinal cord injury based on impact injury from a dropped weight and then intraperitoneally injected the rats with conditioned medium from human dental pulp stem cells.We found that the conditioned medium effectively promoted the recovery of sensory and motor functions in rats with spinal cord injury,decreased expression of the microglial pyroptosis markers NLRP3,GSDMD,caspase-1,and interleukin-1β,promoted axonal and myelin regeneration,and inhibited the formation of glial scars.In addition,in a lipopolysaccharide-induced BV2 microglia model,conditioned medium from human dental pulp stem cells protected cells from pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway.These results indicate that conditioned medium from human dental pulp stem cells can reduce microglial pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway,thereby promoting the recovery of neurological function after spinal cord injury.Therefore,conditioned medium from human dental pulp stem cells may become an alternative therapy for spinal cord injury.

Effect of Autoclave Sterilisation on the Dimensional Stability and Tear Strength of Three Silicone Impression Materials

Objectives: There is a risk of spreading infectious material via non-sterile impressions. The aim of this study was to compare the effect of autoclave sterilisation on dimensional stability and tear strength of impression materials. Methods: Twenty-four specimens were produced using a standard ruled test block for each of three impression materials (Affinis, Aquasil and Speedex) to test dimensional stability. Thirty tear strips for each material were prepared for the tear test (ISO 34-1). Specimens were randomly allocated to 3 different groups (autoclaved, disinfected or untreated). A non-contact scanner was used to analyse dimensional change and a universal testing machine was used to determine tear strengths. Results: There were no significant differences in the test dimensions measured for any of the three impression materials following autoclave treatment compared to the disinfected or untreated control groups. The tear strengths were not adversely affected by autoclave sterilisation at 134&deg;C. Conclusion: These addition and condensation-cured silicone impression materials can be steam autoclaved without adverse effects on dimensional accuracy or tear strength.

Impression 2000——多彩生活尽在幻影

随着互联网和多媒体技术的不断发展,我们越来越需要一款操作简单、功能完备、界面精美的图像编辑软件,来为自己个性化的电脑生活添一份姿彩。近日,美国著名的图像处理软件厂商虹软公司和长城多媒体技术中心联手向国内电脑用户推出了一款全新的图像处理软件——幻影(Impression)2000。这款正在全国各地的金长城软件俱乐部销售点热销的全中文图片编辑软件将满足人们自己动手编创多彩生活的愿望,特别适用于家庭和个人使用。幻影2000荟萃了ArcSoft图像处理软件的精华,提供了完备的图像编辑工具。

RPLP0/TBP are the most stable reference genes for human dental pulp stem cells under osteogenic differentiation

BACKGROUND Validation of the reference gene(RG)stability during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data normalisation.Commonly,in an unreliable way,several studies use genes involved in essential cellular functions[glyceraldehyde-3-phosphate dehydro-genase(GAPDH),18S rRNA,andβ-actin]without paying attention to whether they are suitable for such experimental conditions or the reason for choosing such genes.Furthermore,such studies use only one gene when Minimum Information for Publication of Quantitative Real-Time PCR Experiments guidelines recom-mend two or more genes.It impacts the credibility of these studies and causes dis-tortions in the gene expression findings.For tissue engineering,the accuracy of gene expression drives the best experimental or therapeutical approaches.We cultivated DPSCs under two conditions:Undifferentiated and osteogenic dif-ferentiation,both for 35 d.We evaluated the gene expression of 10 candidates for RGs[ribosomal protein,large,P0(RPLP0),TATA-binding protein(TBP),GAPDH,actin beta(ACTB),tubulin(TUB),aminolevulinic acid synthase 1(ALAS1),tyro-sine 3-monooxygenase/tryptophan 5-monooxygenase activation protein,zeta(YWHAZ),eukaryotic translational elongation factor 1 alpha(EF1a),succinate dehydrogenase complex,subunit A,flavoprotein(SDHA),and beta-2-micro-globulin(B2M)]every 7 d(1,7,14,21,28,and 35 d)by RT-qPCR.The data were analysed by the four main algorithms,ΔCt method,geNorm,NormFinder,and BestKeeper and ranked by the RefFinder method.We subdivided the samples into eight subgroups.RESULTS All of the data sets from clonogenic and osteogenic samples were analysed using the RefFinder algorithm.The final ranking showed RPLP0/TBP as the two most stable RGs and TUB/B2M as the two least stable RGs.Either theΔCt method or NormFinder analysis showed TBP/RPLP0 as the two most stable genes.However,geNorm analysis showed RPLP0/EF1αin the first place.These algorithms’two least stable RGs were B2M/GAPDH.For BestKeeper,ALAS1 was ranked as the most stable RG,and SDHA as the least stable RG.The pair RPLP0/TBP was detected in most subgroups as the most stable RGs,following the RefFinfer ranking.CONCLUSION For the first time,we show that RPLP0/TBP are the most stable RGs,whereas TUB/B2M are unstable RGs for long-term osteogenic differentiation of human DPSCs in traditional monolayers.

Suzhou Impression

I easily got my first offer from a Fortune 500 Group after a week I reached Suzhou.The work- ing location is in the miraculous Suzhou Industrial Park(SIP).Suzhou Industrial Park is a leading model zone in China.Speaking of SIP,I couldn't wait to introduce the housing accumulation fund policy here.