Prediction of Hematoma Expansion in Intracerebral Hemorrhage in 24 Hours by Machine Learning Algorithm.

OBJECTIVE: The significance of noncontrast computer tomography (CT) image markers in predicting hematoma expansion (HE) following intracerebral hemorrhage (ICH) within different time intervals in the initial 24 hours after onset may be uncertain. Hence, our objective was to examine the predictive value of clinical factors and CT image markers for HE within the initial 24 hours using machine learning algorithms. METHODS: Four machine learning algorithms, including extreme gradient boosting (XGBoost), support vector machine, random forest, and logistic regression, were employed to assess the predictive efficacy of HE within every 6-hour interval during the first 24 hours post-ICH. The area under the receiver operating characteristic curves was utilized to appraise predictive performance across various time periods within the initial 24 hours. RESULTS: A total of 604 patients were included, with 326 being male, and 112 experiencing hematoma expansion (HE). The findings from machine learning algorithms revealed that computed tomography (CT) image markers, baseline hematoma volume, and other factors could accurately predict HE. Among these algorithms, XGBoost demonstrated the most robust predictive model results. XGBoost's accuracy at different time intervals was 0.89, 0.82, 0.87, and 0.94, accompanied by F1-scores of 0.89, 0.80, 0.87, and 0.93, respectively. The corresponding area under the curve was 0.96, affirming the precision of the predictive capability. CONCLUSIONS: Computed tomography (CT) imaging markers and clinical factors could effectively predict HE within the initial 24 hours across various time periods by machine learning algorithms. In the expansive landscape of big data and multimodal cerebral hemorrhage, machine learning held significant potential within the realm of neuroscience.

Synthesis of High-Fluorescent Diphenyl-anthracene Derivatives and Application in Detection of Nitroaromatic Explosives and Fingerprint Identification.

The development of high-intensity fluorescent materials is always the focuses and forefront projects because of their important applications in displays, sensing and detection fields. In recent years, the detection of explosives has attracted increasing attention due to security and counterterrorism issues. Herein, two diphenyl-anthracene (DPA) derivatives were designed and synthesized by introducing strong electron withdrawing fluorine atoms and cyano-groups to DPA, which exhibited strong fluorescence both in the solution and solid phase with the absolute quantum yields up to 70.4 % and 45.9 % respectively. The detection behavior of nitroaromatic explosives such as picric acid (PA), 2,4,6-trinitrotoluene (TNT) and 3-Nitropropionic acid (3-NP) also shows good sensitivity with the quenching constant as high as 6.3×104  L mol-1 . Theoretical calculation demonstrates that the fluorescence quenching behavior of the two DPA derivatives is caused by the behavior of photoinduced electron transfer (PET) and the resonance energy transfer (RET) studies explained the higher sensitivity and selectivity of both compounds towards PA than other nitro-containing explosives. Furthermore, the strong solid-state fluorescence of the DPA derivatives also shows excellent advantages in enhancing latent fingerprint recognition.

Extraction, physicochemical properties, and antioxidant activity of natural melanin from Auricularia heimuer fermentation.

Introduction: Natural melanin from Auricularia heimuer have numerous beneficial biological properties, which were used as a safe and healthy colorant in several industries. Methods: In this study, single-factor experiments, Box-Behnken design (BBD), and response surface methodology (RSM) were employed to investigate the effects of alkali-soluble pH, acid precipitation pH, and microwave time on the extraction yield of Auricularia heimuer melanin (AHM) from fermentation. Ultraviolet-visible spectrum (UV-Vis), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), and high-performance liquid chromatography (HPLC) were used to analyze the extracted AHM. The solubility, stability, and antioxidant activities of AHM were also measured. Results: The results showed that alkali-soluble pH, acid precipitation pH, and microwave time significantly affected the AHM yield, with the following optimized microwave-assisted extraction conditions: alkali-soluble pH of 12.3, acid precipitation pH of 3.1, and microwave time of 53 min, resulting in an AHM extraction yield of 0.4042%. AHM exhibited a strong absorption at 210 nm, similar to melanin from other sources. FT-IR spectroscopy also revealed that AHM exhibited the three characteristic absorption peaks of natural melanin. The HPLC chromatogram profile of AHM showed a single symmetrical elution peak with a 2.435 min retention time. AHM was highly soluble in alkali solution, insoluble in distilled water and organic solvents, and demonstrated strong DPPH, OH, and ABTS free radical scavenging activities. Discussion: This study provides technical support to optimize AHM extraction for use in the medical and food industries.

Incidental finding of metastatic prostatic adenocarcinoma of cerebellopontine angle presenting as acoustic neuroma: A case report and review of literature.

INTRODUCTION: Brain metastases from carcinoma of prostate are rare and only few cases with brain metastases preceding the diagnosis of carcinoma of prostate have been reported in the literature. Lesions of brain metastasis from prostate cancer had a large variety of imaging presentations and it is very difficult to distinguish them from the other types of brain occupying lesions. We report one case of metastatic prostatic adenocarcinoma of cerebellopontine angle presenting as acoustic neuroma, as the first clinical evidence of metastatic carcinoma of the prostate. PRESENTATION OF CASE: The 57-year-old male presented to the neurology clinic complaining of dizziness accompanied by right tinnitus, he was proposed to be diagnosed with acoustic neuroma, and the tumor resection was performed later in our neurosurgery department. The postoperative histopathological and immunohistochemical (IHC) examinations revealed a cerebellar pontine angle metastatic adenocarcinoma, which was then confirmed as prostate cancer metastasis. The patient refused surgical castration and only agreed to conservative treatment. The patient's condition continued to deteriorate, and he died 12 months after the initial presentation. DISCUSSION: Brain metastasis is rare in prostate cancer, which accounts for only 0.2 % to 2 % of all brain metastases. Intracranial metastasis as the first clinical symptom of prostate cancer is extremely rare. In our article, we report the VIIIth and VIIth cranial nerves palsy for the first time, caused by brain metastases from prostate cancer, with symptoms similar to an acoustic neuroma. Prostate cancer most commonly spreads to the bones, including the skull, Cranial nerve palsy is caused by extensive invasion of the skull base. The serum PSA level is considered the most valuable tool to monitor the disease progression of patients with prostate cancer metastasis. A high PSA level significantly increases the tendency of prostate cancer to metastasize to the brain. A high Gleason score is believed to help determine the risk and likelihood of brain metastases in patients with prostatic carcinoma. CONCLUSION: In our case, we initially report the VIIIth and VIIth cranial nerve palsy, mimicking an acoustic neuroma, caused by metastatic prostate carcinoma. For early diagnosis, the prostate should not be neglected as a possible source of the metastases in male patients presenting with brain metastases. High prostate specific antigen (PSA) level and high Gleason score can be useful parameters for the prediction of brain metastasis from prostate cancer. The PSA should play a vital role in distinguishing metastatic prostate carcinoma in male patients.

Synthesis and characterization of naphthalene derivatives for two-component heterojunction-based ambipolar field-effect transistors complemented with copper hexadecafluorophthalocyanine (F16CuPc).

In order to develop organic semiconductor materials with good performance, herein, a series of naphthalene derivatives were designed and synthesized by a "building-blocks approach" connected through α-bond, double bond, and triple bond, respectively. Thin-film transistors were fabricated in single-component and two-component modes based on these naphthalene derivatives by combining the F16CuPc as the n-type material. The ambipolar performance was investigated by adjusting the device preparation procedure with the hole and electron mobility of up to 10-2 cm2 V-1 s-1. Furthermore, the electrical performance was also improved to 0.73 cm2 V-1 s-1 using the two-component bilayer configuration.

Simultaneous enrichment of inorganic and organic species of lead and mercury in pg L-1 levels by solid phase extraction online combined with high performance liquid chromatography and inductively coupled plasma mass spectrometry.

Quantification of ultra-trace inorganic and organic species of lead and mercury in unpolluted environmental water is crucial to estimate the mobility, toxicity and bioavailability and interactions. Simultaneous pre-concentration of Pb and Hg species in pg L-1 levels followed by multi-elemental speciation analysis makes great sense to a large set of unstable samples because of time advantages. Herein simultaneous enrichment and speciation analysis of ultra-trace lead and mercury in water was developed by online solid-phase extraction coupled with high performance liquid chromatography and inductively coupled plasma mass spectrometry (SPE-HPLC-ICP-MS) for this aim. Pb(II), trimethyl lead (TML), triethyl lead (TEL), Hg(II), methylmercury (MeHg) and ethylmercury (EtHg) were baseline separated in 11 min under gradient elution using 5 mM l-cysteine (Cys) at pH 2.5 in the 0-1 and 4-15 min and 5 mM Cys + 0.5 mM tetrabutyl ammonium hydroxide solution at pH 2.5 in the 1-4 min. Lead and mercury species in 10 mL intact water samples were adsorbed on a 1 cm C18 enrichment column pre-conditioned with 10 mL of 1 mM 2-mercaptoethanol at 10 mL min-1, and then directly desorbed by the mobile phases. High enrichment factors (459 for Pb(II), 1248 for TML, 1627 for TEL, 2485 for Hg(II), 1984 for MeHg and 1866 for EtHg) were obtained with good relative standard deviations (<5%), leading to low LODs (0.001-0.011 ng L-1) and LOQs (0.004-0.036 ng L-1). Good accuracy of this method was validated by two certified reference materials of total lead in water (GBW08601) and total mercury in water (GBW08603) along with spiked recoveries (89-93%). The method was applied to analyze trace lead and mercury species in river, lake, tap and rain water, and purified and mineral water. Inorganic lead of 13-68 ng L-1 and inorganic mercury of 21-49 ng L-1 were measured in the nine water samples whereas TML, TEL and MeHg were not detected with 2-5 ng L-1 EtHg presented only in one river water and tap water.

Prediction of Poor Outcome in Intracerebral Hemorrhage Based on Computed Tomography Markers.

INTRODUCTION: Intracerebral hemorrhage (ICH) is the most fatal type of stroke worldwide. Herein, we aim to develop a predictive model based on computed tomography (CT) markers in an ICH cohort and validate it in another cohort. METHODS: This retrospective observational cohort study was conducted in 3 medical centers in China. The values of CT markers, including hypodensities, hematoma density, blend sign, black hole sign, island sign, midline shift, baseline hematoma volume, and satellite sign, in predicting poor outcome were analyzed by logistic regression analysis. A nomogram was developed based on the results of multivariate logistic regression analysis in development cohort. Area under curve (AUC) and calibration plot were used to assess the accuracy of nomogram in this development cohort and validate in another cohort. RESULTS: A total of 1,498 patients were included in this study. Multivariate logistic regression analysis indicated that hypodensities, black hole sign, island sign, midline shift, and baseline hematoma volume were independently associated with poor outcome in development cohort. The AUC was 0.75 (95% confidence interval [CI]: 0.73-0.76) in the internal validation with development cohort and 0.74 (95% CI: 0.72-0.75) in the external validation with validation cohort. The calibration plot in development and validation cohort indicated that the nomogram was well calibrated. CONCLUSIONS: CT markers of hypodensities, black hole sign, and island sign might predict poor outcome of ICH patients within 90 days.

Quantification of ultra-trace organolead species in environmental water by inductively coupled plasma mass spectrometry with online solid-phase extraction and high performance liquid chromatographic separation.

Quantification of organolead compounds in environmental water is an essential task considering much higher toxicity and bioavailability of organolead species than inorganic plumbic ions. However, the speciation of ultra-trace organolead compounds at sub ng L-1 levels is challengeable for current instruments incorporating high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) and even offline enrichment that offer detection limits around several to tens of ng L-1. In this paper, an online solid-phase extraction (SPE) coupled HPLC-ICP-MS method was developed for speciation analysis of trace lead in water. Graphene oxide bounded silica particles (GO@SiO2) was utilized as the SPE adsorbent because of its superior performance over graphene bounded silica particles and commercial C18 packing particles. High enrichment factors (1603 for TML and 1376 for TEL) were obtained when lead species in 10 mL sample was adsorbed by 1 mM sodium dodecyl benzene sulfonate (SDBS) preconditioned GO@SiO2 at 10 mL min-1 and then eluted by 5 µL of 5 mM SDBS. Because of the highly efficient preconcentration, detection limits were downscaled to be 0.018 for TML and 0.023 ng L-1 for TEL with relative standard deviations below 5%. Additionally, the proposed method also yielded rapid separation of Pb(II), TML and TEL (8 min) by using green mobile phases (aqueous solutions of 5 mM sodium 1-pentanesulfonate at pH 2.5 with/without 4 mM tetrabutylammounium hydroxide). Upon successful application to fresh water, TML and TEL were only presented in the river water whereas Pb(II) was only existed in the tap water, along with accuracy validation by good spiked recoveries (93-106%).

The effect of tranexamic acid in patients with TBI: a systematic review and meta-analysis of randomized controlled trials.

To conduct a systematic review and meta-analysis and evaluate the effect of tranexamic acid in patients with traumatic brain injury. PubMed, EMBASE, and CENTRAL (Cochrane Central Register of Controlled Trials) were searched to identify randomized controlled trials and evaluate the effect of tranexamic acid in traumatic brain injury patients. The primary outcome was mortality. Two reviewers extracted the data independently. The random effect meta-analysis was used to estimate the aggregate effect size of 95% confidence intervals. Six randomized controlled trials investigating tranexamic acid versus placebo and 30073 patients were included. Compared with placebo, tranexamic acid decreased the mortality (RR = 0.92; 95% CI, 0.87-0.96; p < 0.001) and growth of hemorrhagic mass (RR = 0.78; 95% CI, 0.61-0.99; p = 0.04). However, tranexamic acid could not decrease disability or independent, neurosurgery, vascular embolism, and stroke. Current evidence suggested that compared with placebo, tranexamic acid could reduce mortality and growth of hemorrhagic mass. This finding indicated that patients with traumatic brain injury should be treated with tranexamic acid.

A novel model for predicting the outcome of intracerebral hemorrhage: Based on 1186 Patients.

OBJECTIVE: To establish a model for predicting the outcome according to the clinical and computed tomography(CT) image data of patients with intracerebral hemorrhage(ICH). METHODS: The clinical and CT image data of the patients with ICH in Qinghai Provincial People's Hospital and Xuzhou Central Hospital were collected. The risk factors related to the poor outcome of the patients were determined by univariate and multivariate logistic regression analysis. To determine the effect of factors related to poor outcome, the nomogram model was made by software of R 3.5.2 and the support vector machine operation was completed by software of SPSS Modelor. RESULTS: A total of 8265 patients were collected and 1186 patients met the criteria of the study. Age, hospitalization days, blend sign, intraventricular extension, subarachnoid hemorrhage, midline shift, diabetes and baseline hematoma volume were independent predictors of poor outcome. Among these factors, baseline hematoma volume๥20ml (odds ratio:13.706, 95% confidence interval:9.070-20.709, p < 0.001) was the most significant factor for poor outcome, followed by the volume among 10ml-20ml (odds ratio:11.834, 95% confidence interval:7.909-17.707, p < 0.001). It was concluded that the highest percentage of weight in outcome was baseline hematoma volume (25.0%), followed by intraventricular hemorrhage (23.0%). CONCLUSION: This predictive model might accurately predict the outcome of patients with ICH. It might have a wide range of application prospects in clinical.

Nomogram Model for Predicting Hematoma Expansion in Spontaneous Intracerebral Hemorrhage: Multicenter Retrospective Study.

OBJECTIVE: To establish a new nomogram model and provide a new theoretical basis for the diagnosis and treatment of spontaneous intracerebral hemorrhage. METHODS: The clinical data and noncontrast computed tomography images of patients with spontaneous intracerebral hemorrhage in 3 tertiary medical centers were collected continuously. Univariate and binary logistic regression analysis were performed to screen out the independent predictors that were significantly associated with hematoma expansion. The nomogram model was drawn by R programming language. According to the related risk factors of nomogram, decision curve analysis and clinical impact curve were established. RESULTS: The numbers of the 3 cooperative units were 554, 582, and 202, respectively. Island sign, blend sign, swirl sign, intraventricular hemorrhage, history of diabetes, time to baseline computed tomography scan, and baseline hematoma volume were independent predictors of hematoma expansion. Baseline hematoma volume >20 mL (odds ratio, 4.088; 95% confidence interval, 2.802-5.964; P < 0.0001) was the most dangerous factor for predicting hematoma expansion, followed by the time to baseline computed tomography scan ≤1 hour (odds ratio, 4.188; 95% confidence interval, 2.598-6.750; P < 0.0001). Decision curve analysis showed that the net benefit of patients was the highest when nomogram score existed. When the threshold probability was >40%, the prediction probability of hematoma expansion was close to the actual probability. CONCLUSIONS: This nomogram model could accurately predict hematoma expansion of spontaneous intracerebral hemorrhage, which provided a theoretical basis for clinicians to intervene in the early stage.

Simultaneous multi-elemental speciation of As, Hg and Pb by inductively coupled plasma mass spectrometry interfaced with high-performance liquid chromatography.

This work establishes a hyphenated methodology coupling HPLC with ICP-MS for simultaneous speciation analysis of arsenic, mercury and lead for the first time. Four arsenicals (As(III), DMA, MMA and As(V)), four mercurials (Hg(II), MeHg, EtHg and PhHg) and three lead compounds (Pb(II), TML and TEL) were simultaneously analyzed within only 8 min with acceptable resolution (2.0-8.2 for As, 1.6-6.1 for Hg and 2.7-4.0 for Pb). The detection limits were 0.036-0.20 for As-species, 0.023-0.041 for Hg-species, and 0.0076-0.14 µg L-1 for Pb-species. The developed method was applied for the measurement of five lotus seed samples, indicating the presence of DMA (19.6-28.2 µg kg-1), TML (1.4-2.9 µg kg-1), MeHg (1.2-4.8 µg kg-1) and EtHg (0.8-2.2 µg kg-1). This method provides a promising tool for studying the toxic, metabolic and bioavailable behaviors of arsenic, mercury and lead.

Optimization of Melanin Extraction from the Wood Ear Medicinal Mushroom, Auricularia auricula-judae (Agaricomycetes), by Response Surface Methodology and Its Antioxidant Activities In Vitro.

The optimal conditions for melanin extraction from Auricularia auricula-judae (Hei 29) fruiting bodies was determined on the basis of the extract yield of melanin, calculated by using a single-factor experiment and response surface methodology. Its antioxidant activities were also studied in vitro. Various optimal process conditions for melanin extraction were determined by using Design-Expert software: incubation temperature, 69.11°C; incubation time, 58.66 minutes; and incubation pH, 12.81. Under these conditions, the melanin yield was 2.59%. We found that the antioxidant activities of A. auricula-judae melanin in vitro were strong against DPPH radicals and superoxide anions. The rate of DPPH radical scavenging was 63.04% when the A. auricula-judae melanin concentration was 0.36 mg/mL; the rate of superoxide anion scavenging reached 39.79% when the concentration was 0.375 mg/mL. However, the antioxidant activity against hydroxyl radicals was somewhat weak; the rate of scavenging reached only 7.47% when the A. auricula-judae melanin concentration was 0.06 mg/mL.

Identification of a New Fungal Pathogen Causing White Villous Disease on the Fruiting Body of the Culinary-Medicinal Mushroom Auricularia auricula-judae (Agaricomycetes) in China.

Auricularia auricula-judae is an edible and medicinal fungus ranking fourth in production among the edible fungi cultivated worldwide. White villous disease is rampant in Northeast China; it infects the fruiting bodies of A. auricula-judae by forming a white mycelial layer on its ventral side. The disease not only causes an unacceptable morphological appearance and a poor-quality product, but it also significantly reduces the yield. In this study, based on fungal morphology, ribosomal DNA internal transcribed spacer sequences, identification of species-specific primers, and the pathogenicity of the mycelia and spores, 2 fungal pathogens were isolated and identified as Fusarium equiseti and F. sporotrichioides.

Long non-coding RNA TUG1 acts as a miR-26a sponge in human glioma cells.

BACKGROUND: Long non-coding RNA taurine upregulated gene 1 (TUG1) acts as an important regulator in cancer pathogenesis; however, its functional mechanism in glioma development remains unclear. This study aims to explore the potential function of TUG1 in glioma by sponging miR-26a. METHODS: The expression of TUG1, miR-26a, and phosphatase and tensin homolog (PTEN) in 20 paired glioma tissues was detected by quantitative real-time PCR and subjected to correlation analysis. Bioinformatics analysis was performed by using DIANA Tools. Abnormal TUG1 expression was conducted in two glioma cells to analyze its regulation on miR-26a and PTEN using real-time PCR, western blot, and luciferase reporter assay. RESULTS: TUG1 expression was confirmed to be upregulated in glioma tissues, and showed an inverse correlation with downregulated miR-26a. TUG1 could negatively regulate the expression of miR-26a in glioma cells. The bioinformatics prediction revealed putative miR-26a binding sites within TUG1 transcripts. Further experiments demonstrated the positive regulation of TUG1 on the miR-26a target, PTEN, wherein TUG1 could inhibit the negative regulation of miR-26a on PTEN by binding its 3'UTR. Additionally, the expression of PTEN was also upregulated in glioma tissues, showing a positive or negative correlation with TUG1 or miR-26a, respectively. CONCLUSION: TUG1 could serve as a miR-26a sponge in human glioma cells, contributing to the upregulation of PTEN. This study revealed a new TUG1/miR-26a/PTEN regulatory mechanism and provided a further understanding of the tumor-suppressive role of TUG1 in glioma development.

LncRNA TUG1 acts as a tumor suppressor in human glioma by promoting cell apoptosis.

Previous studies have revealed multiple functional roles of long non-coding RNA taurine upregulated gene 1 in different types of malignant tumors, except for human glioma. Here, it was designed to study the potential function of taurine upregulated gene 1 in glioma pathogenesis focusing on its regulation on cell apoptosis. The expression of taurine upregulated gene 1 in glioma tissues was detected by quantitative RT-PCR and compared with that in adjacent normal tissues. Further correlation analysis was conducted to show the relationship between taurine upregulated gene 1 expression and different clinicopathologic parameters. Functional studies were performed to investigate the influence of taurine upregulated gene 1 on apoptosis and cell proliferation by using Annexin V/PI staining and cell counting kit-8 assays, respectively. And, caspase activation and Bcl-2 expression were analyzed to explore taurine upregulated gene 1-induced mechanism. taurine upregulated gene 1 expression was significantly inhibited in glioma and showed significant correlation with WHO Grade, tumor size and overall survival. Further experiments revealed that the dysregulation of taurine upregulated gene 1 affected the apoptosis and cell proliferation of glioma cells. Moreover, taurine upregulated gene 1 could induce the activation of caspase-3 and-9, with inhibited expression of Bcl-2, implying the mechanism in taurine upregulated gene 1-induced apoptosis. taurine upregulated gene 1 promoted cell apoptosis of glioma cells by activating caspase-3 and -9-mediated intrinsic pathways and inhibiting Bcl-2-mediated anti-apoptotic pathways, acting as a tumor suppressor in human glioma. This study provided new insights for the function of taurine upregulated gene 1 in cancer biology, and suggested a potent application of taurine upregulated gene 1 overexpression for glioma therapy.

Replacement of severely traumatized teeth with immediate implants and immediate loading: literature review and case reports.

One of the options for management of severely traumatized dentitions is to provide immediate implant placement with immediate loading. Three representative cases out of 15 patients with 23 traumatized teeth treated to date in our clinic are presented. None had labial bone fractures. The teeth were replaced with NobelReplace Groovy implants (Nobel Biocare, Gothenburg, Sweden) in the fresh sockets immediately after extraction. They were placed toward the palatal areas in the sockets and 3 mm below the gingival margins. If there were gaps between implants and sockets wider than 1 mm, particulate deproteinized bovine bone was grafted in the gaps. Immediately after placement, the implants were loaded with provisional prostheses. The final restorations were installed 3-4 months later. The patients were reevaluated clinically and radiographically 1-3 years after the final restorations had been placed. In all 15 patients, excellent functional and esthetic results were achieved. No implants showed radiolucency, peri-implant suppuration, or mobility. The patients were satisfied with the results. Immediate implant placement with immediate loading is an option that provides good treatment outcomes and allows good functional and esthetic results, as well as addressing the social/psychological aspects of dental trauma.

Marginal and internal fit of two different zirconium copings fabricated on the implant abutment.

OBJECTIVE: To evaluate the accuracy of marginal and internal fit of the zirconium copings manufactured by two different computer-aided design(CAD)/computer-aided manufacturing(CAM)system on the implant abutment. METHODS: Using different scanning mode,five Procera(®) zirconium copings and five Lava zirconium copings were fabricated on the same implant abutment, and then compared with five precious metal copings fabricated by traditional method. Fifteen abutment replica were made with die-stone and the copings were randomly cemented on them, then they were sectioned and invested. The marginal, shoulder, occlusal, and axial fit of each sample was measured by scanning electron microscopy (SEM). RESULTS: There was no significant difference in marginal and axial fit among the three groups(P>0.05). Significant difference in occlusal fit was found among the three groups(P<0.05): Lava group showed better fit than the others(P<0.05)and Procera(®) group showed better fit than the control(P<0.05). CONCLUSIONS: These two types of zirconium coping have clinically acceptable marginal and internal fit. The internal fit of zirconium coping may be affected by different manufacturing techniques.