Objective To investigate the current ~atus of mercury thermometer applied in China and the replacement of it by electric thermometer.Methods A systematic review of the literatures was undertaken,and the mercury pollution caused by mercury thermometer was reviewed,the measures taken by various countries to reduce the use of mercury thermometer were introduced.The difficulty in promoting electric thermometer in China was analyzed,and some measures were proposed accordingly.Results Most of the population including medical staffs had few awareness of the hazard of mercury thermometer to the environment,while the promotion of electric thermometer was obstructed due to the deficiencies in propaganda andpolicies.Conclusion It's suggested emphases be placed on propaganda and measures to replace mercury thermometer by electric one to decrease mercury pollution.

Objective To study the expression of double-stranded RNA-dependent protein kinase (PKR) in malignant melanoma and ordinary nevi. Methods The expression of PKR and proliferating cell nuclear antigen was examined in 42 cases of malignant melanoma and 25 ordinary nevi by an immunohistochemical method. Results The positive rate of PKR expression was higher in the patients with malignant melanoma than that in the patients with ordinary nevi (P

OBJECTIVEThis study aimed to investigate the influence of coping material and porcelain firing on the marginal and internal fit of computer-aided design/computer-aided manufacturing (CAD/CAM) of zirconia ceramic implant- and titanium ceramic implant-supported crowns.

METHODSZirconia ceramic implant (group A, n = 8) and titanium metal ceramic implant-supported crowns (group B, n = 8) were produced from copings using the CAD/CAM system. The marginal and internal gaps of the copings and crowns were measured by using a light-body silicone replica technique combined with micro-computed tomography scanning to obtain a three-dimensional image. Marginal gap (MG), horizontal marginal discrepancy (HMD), and axial wall (AW) were measured. Statistical analyses were performed using SPSS 17.0.

RESULTSPrior to porcelain firing, the measurements for MG, HMD, and AW of copings in group A were significantly larger than those in group B (P < 0.05). After porcelain firing, the measurements for MG of crowns in group A were smaller than those in group B (P < 0.05), whereas HMD and AW showed no significant difference between the two groups (P > 0.05). Porcelain firing significantly reduced MG (P < 0.05) in group A but significantly increased MG, HMD, and AW in group B (P < 0.05) HMD and AW were not influenced by porcelain firing in group A (P > 0.05).

CONCLUSIONThe marginal fits of CAD/CAM zirconia ceramic implant-supported crowns were superior to those of CAD/CAM titanium ceramic-supported crowns. The fits of both the CAD/CAM zirconia ceramic implant- and titanium ceramic implant-supported crowns were obviously influenced by porcelain firing.

Ceramics ; Computer-Aided Design ; Crowns ; Dental Porcelain ; Dental Prosthesis Design ; Humans ; Titanium ; X-Ray Microtomography ; Zirconium

OBJECTIVETo evaluate the effect of different auxiliary resistance forms on the resistance and marginal fitness of complete crowns for short molar preparations.

METHODSA total of 70 Nissin resin teeth were prepared with 20° total occlusal convergence, 2.5 mm of occlusocervical height, and a shallow finish line on a milling machine. The milled preparations were then randomly assigned to 7 groups of 10. The first group was used as the control group. A total of 30 dies were modified by preparing interproximal grooves with angles of 0°, 6°, and 20° centered on the mesial and distal surfaces of the dies. The rest of the teeth were prepared with occlusal holes in the center of the occlusal surface milled with the same burs to form 0°, 6°, and 20° holes. Cobalt-chromium copings were fabricated for all specimens. The marginal gap of specific points on the axial surface was measured before and after cementation. The resistance of each specimen was evaluated by applying an external force at an angle of 45° to the long axis of the die by using a universal testing machine in a lingual to buccal direction. The maximum force applied before crown dislodgement was measured. Data were analyzed using the SAS 9.2 software.

RESULTSThe results showed that the 0° groove, 0° hole, and 6° hole were effective in improving the resistance of the complete crowns (P<0.05). The 0° groove, 6° groove, 0° hole, 6° hole, and 20° hole had significant difference with the control group in terms of marginal discrepancies (P<0.05).

CONCLUSIONAuxiliary resistance forms with less degree indicate greater resistance force but worse marginal fitness. In clinical practice, if the resistance of a preparation is enough, the auxiliary resistance forms should be avoided from being used.

Cementation ; Crowns ; Dental Prosthesis Design ; Dental Prosthesis Retention ; Humans ; Molar ; Tooth Crown

OBJECTIVETo evaluate the effect of different root canal irrigants and cements on coronal microleakage and the interaction effects after cementing metal post-cores.

METHODSNinety newly extracted single-rooted mandibular human premolars were endodontically treated. Post spaces were prepared in the root canals, and Co-Cr post-cores were cast routinely. The specimens were randomly divided into six groups (n = 15) via a two-way factorial design method. The irrigant factors (A) included A1: no irrigant (75% alcohol wiping), A2: 3% H2O2 + 0.9% NaCl, and A3: 15% ethylenediamine tetraacetic acid (EDTA) + 5.25% NaClO. The cement factors (B) included B1: zinc polycarboxylate cement, and B2: glass ionomer cement. The specimens received treatments based on the grouping of A1B1, A1B2, A2B1, A2B2, A3B1, and A3B2. All samples were sectioned longitudinally after being immersed in India ink for three weeks. The microleakages were observed using a stereomicroscope. The SPSS 13.0 software package was used for factorial analysis.

RESULTSThe mean microleakage scores and standard deviations were as follows: Group A1BI: (1,192.59 +/- 417.84) microm, Group A1B2: (1,317.38 +/- 527.35) microm, Group A2B1: (1,429.33 +/- 482.68) microm, Group A2B2: (1,026.79 +/- 459.49) microm, Group A3B1: (1,448.29 +/- 561.02) microm, and Group A3B2: (1,922.47 +/- 678.86) microm. The A2B2 group showed minimum microleakage, whereas the A3B2 group showed maximum microleakage. The microleakage degrees among different irrigants presented significant statistical difference (P < 0.05), but the two cements showed no significant difference (P > 0.05). An interactive effect on the microleakage existed between the irrigants and the cements after cementing the metal post-cores (P < 0.05).

CONCLUSIONWhen cementing metal post-cores, the coronal microleakage following 3% H2O2 + 0.9% NaCl irrigation combined with glass ionomer cement can be reduced. The combined application of 15% EDTA + 5.25% NaClO and glass ionomer cement significantly aggravates microleakage.

Cementation ; Dental Cements ; Dental Leakage ; Glass Ionomer Cements ; Humans ; Hydrogen Peroxide ; Metals ; Post and Core Technique ; Resin Cements ; Root Canal Irrigants

Objective To investigate the clinicopathological and prognosis features of enteropathy-associated T-cell lymphoma (EATL).Methods 21 cases of EATL,6 cases of peripheral T-cell lymphoma (PTCL) and 11 cases of natural-killer/T-cell lymphoma (NKTCL) were collected from January 2008 to May 2015.The immunophenotype of the tumor cell was tested by EnVision and as well as EBV-EBER for EB virus.Some patients were performed with follow-up data.Results 21 EATL patients included 14 males,7 females and the middle age was 55 years old (40-79 years old).15 patients affected the small bowel,4 cases affected colon,2 cases affected more than one site.18 cases were mono-morpholohic EATL while 3 cases were classical EATL.The expression rates of neoplastic cells for CD3ε,CD4,CD8,CD56,Granzyme B,TIA-1 were 95.24 ％ (20/21),20.00 ％ (3/15),73.68 ％ (14/19),85.71％ (18/21),64.71％ (11/17),88.89 ％ (16/18) respectively.The expression of EBER in EATL patients (0,0/21) was obviously lower than that in NKTCL patients (100 ％,11/11).17 EATL patients had follow-up data,and the middle survival time was 15 months.No different prognosis was found in the three kinds of T-NHL (P =0.697).Conclusions EATL usually occurs in elder male and jejunum.The diagnosis of EATL needs a lot of information,including clinical history,endoscopy,histomorphology,immunophenotype and EBV-EBER result.EATL has low mobidity and high malignancy,it still lacks impactful therapeutic regimen.

Objective To elucidate clinical pathological features of primary mediastinal B-cell lymphoma (PMBL) and its difference compared with diffuse large B-cell lymphoma,not otherwise specified (DLBCL,NOS).Methods The clinical histories and pathological datas of 24 PMBL cases and 31 cases of DLBCL,NOS as the control group were collected.Immunohistochemical staining and a follow-up study was conducted.Results The distribution of gender showed significant difference when the age of onset of PMBL patients was obviously younger with the medial age of 30 years old (P ＜ 0.001).All cases presented as a huge mass in mediastinal site with compression symptoms.PMBL was similar to DLBCL in the morphology of tumor cells but fibrosis of various degrees was common,more than 70.8 ％ (17/24) cases had the collagen bundles split.CD23 positive rate (40.0 ％,6/15) in PMBL was significantly higher than the control group (3.2 ％,1/31)(P =0.003).Conclusion PMBL frequently occurs in young female people,mostly happens in mediastinal site and adjacent area,but rarely has distant dissemination.PMBL has the characteristics of various degrees of collagen fiber hyperplasia,and CD23 positive could be used to differentiate PMBL from DLBCL,NOS.

Objective To investigate the distribution of gut microbiota in obese patients with or without acanthosis nigricans .Methods Totally 131 obese patients and 25 healthy participants were divided into three groups:the obesity with acanthosis nigricans (AN) group (n=59), the simple obesity (OB) group (n=79), and the control (CON) group (n=25).The fresh stool samples were collected , and the clinical and biochemistry markers were measured .Pyrosequencing technology was performed based on the 16s rRNA of fecal samples to identify and analyze the distribution pattern of gut microbiota in each group .Results The AN group had signifi-cantly higher body mass index [ (37.45 ±5.12) kg/m2 vs.(33.34 ±2.54) kg/m2 vs. (20.35 ±1.68) kg/m2, P=0.045, P<0.001], insulin [32.77 (25.18) mU/L vs.20.73 (9.30) mU/L vs.8.70 (6.18) mU/L, P<0.001, P<0.001], insulin resistance [7.78 (6.87) vs.4.71 (2.88) vs.1.81 (1.40), P<0.001, P<0.001], and interleukin (IL) -6 [ (3.64 ±2.23) ng/L vs.(2.71 ±0.78) ng/L vs.(2.17 ±0.86) ng/L, P=0.040, P=0.009] levels than OB and CON groups compared with OB and CON groups , AN group had sig-nificantly decreased diversity of bacterial flora ( P=0.015 , P=0.001 ) , while no significant difference was observed in the abundance of bacterial flora .At the phylum level , the composition of flora among these three groups was similar, mainly including bacteroidetes , firmicutes, proteobacteria, and actinomycetes.Although the proportions of main bacteria flora were different , the difference was not statistically significant .At the genus level, the bacteria flora in AN and OB groups were primarily composed of Bacteroides, Megamonas, Faecalibac-terium and Escherichia-Shigella.In addition, compared to OB and CON groups , AN group had significantly lower proportion of Ruminococcus ( P=0.023 , P=0.043 , respectively ) and higher proportion of Veillonella (P=0.048, P=0.043, respectively).Furthermore, the proportion of Weissella was higher in AN and OB groups than in CON group ( P=0.045 , P=0.025 ) .Conclusion Obese patients with AN have more severe in-sulin resistance and inflammation status than those with simple obesity , and the distribution feature of gut micro-biota also differ between these two patient populations .

OBJECTIVETo evaluate the influence of eugenol-containing and resin-containing endodontic sealers on the bond strength of fiber posts using different strategies of root canal irrigation.

METHODSForty-eight mandibular premolars were endodontically treated. The specimens were randomly assigned into two groups according to different endodontic sealers. Group A used Endofil (eugenol-containing endodontic sealer), and group B used AH-plus (resin-containing endodontic sealer). After post space preparation, each group was randomly assigned into three subgroups according to the strategies of root canal irrigation (eight premolars in each subgroup). Group Al and B1: 0.9%NaCl irrigation; Group A2 and B2: 17% ethylene diamine tetraacetic acid (EDTA)+5.25%NaClO+0.9%NaCl irrigation; Group A3 and B3: ultrasonic agitation associated with 1 7%EDTA+5.25%NaClO+0.9%NaCl. One week after the cementation of fiber posts using RelyX™ Unicem, a push-out test was performed to measure the bond strength of the posts. The microstructure of the root canal surface was examined under scanning electron microscope (SEM).

RESULTSThe bond strengths of the six groups were as follows: Al (7.96±2.23) MPa, A2 (9.95±2.89) MPa, A3 (18.88±3.69) MPa, B1 (11.41±3.71) MPa, B2 (14.00±4.04) MPa, and B3 (19.14±3.27) MPa. Statistical analysis revealed a significant interaction between the different endodontic sealers and the strategies of root canal irrigation (P<0.05). Lower bond strength was found in group Al but not in group BI (P<0.05), and the same result was revealed when comparing group A2 and B2. No significant difference was observed between group A3 and B3 (P>0.05). SEM showed that the root canal in group A3 and B3 achieved the cleanest surface with nearly all dentine tubules opened.

CONCLUSIONThe eugenol-containing endodontic sealer can impair the bond strength of fiber posts compared with the resin-containing sealer when the root canal is irrigated by 0.9% NaCl or 17%EDTA+5.25%NaClO+0.9%NaC. No difference was observed between the two sealers when using 17%EDTA+5.25% NaCIO+0.9%NaCl combined with ultrasonic irrigation.

Bicuspid ; Cementation ; Dental Bonding ; Dental Pulp Cavity ; Dental Stress Analysis ; Dentin ; Humans ; Post and Core Technique ; Root Canal Filling Materials ; Root Canal Irrigants ; Root Canal Therapy

OBJECTIVEThis study investigated the influence of different designs and porcelain/glaze firing on the marginal and internal fit of three kinds of computer aided design/computer aided manufacturing (CAD/CAM) zirconia ceramic implant-supported crowns.

METHODSThree groups of zirconia ceramic implant-supported crowns with different designs were produced from copings by using a Cercon CAD/CAM system (n = 8). The first two groups comprised double-layer crowns (zirconia coping + veneer) with regular (Group A) and full circumferential zirconia-collar marginal designs (Group B). The third group was composed of anatomic single-layer zirconia crowns without cores (Group C). Initially, the marginal and internal gaps of the copings and crowns were individually replicated by light-body silicon and then measured by micro-computed tomography scanning before and after porcelain/glaze firing. Five measurements were employed: vertical marginal gap (MG); horizontal marginal discrepancy (HMD); chamfer area (CA); axial wall (AW); and axial-occlusal transition area (AOT). Statistical analyses were performed by SPSS 17.0.

RESULTSHMD measurements in Group A were statistically higher than those in Groups B and C (P < 0.05), regardless of whether the values were obtained before or after porcelain/glaze firing. By contrast, the HIMD measurements in Groups B and C showed no significant difference (P > 0.05). Moreover, no differences were noted in MG, CA, AW, and AOT among the three groups (P > 0.05). All the measurements in the three groups showed no significant change after porcelain/glaze firing (P > 0.05), except for MG in Group A, which significantly decreased (P < 0.05).

CONCLUSIONThe marginal fits of the double-layer crowns with full circumferential zirconia-collar and the anatomic single-layer zirconia crowns were superior to that of the double-layer crowns with regular margins. The MG of the crowns with regular margins was obviously influenced by porcelain firing.

Computer-Aided Design ; Crowns ; Dental Porcelain ; Dental Prosthesis Design ; X-Ray Microtomography ; Zirconium