Umbilical vascular catheter rupture: a case report and literature review / 中国新生儿科杂志

Objective:To study the clinical characteristics of neonatal umbilical vascular catheter (UVC) rupture.Methods:A neonate with UVC rupture admitted to Neonatology Department of our hospital was retrospectively reviewed. Literature on this subject were searched in the following databases: Chinese Medical Journal full-text Database, CNKI, Wanfang Database, CQVIP database, PubMed, Web of Science, Embase and Cochrane Library (up until March 15 2022). The causes, treatment and prognosis of neonatal UVC rupture were analyzed.Results:In our case, the UVC was accidentally damaged during the removal of the ligature suture. The UVC was ruptured after a slight force was applied to remove the catheter, resulting in approximately 7 cm of UVC remaining in the body. Trans-umbilical vein intervention was performed and the catheter was successfully removed with a lasso under X-ray guidance. A total of 33 UVC rupture cases were included from 15 articles (no case report in China before). In 16 cases (47.1%), the UVCs were accidentally cut off by knife or scissors when removing the catheter. In 3 cases (8.8%), the UVCs were broken during insertion. The UVC was broken in 1 case (2.9%) during flushing the catheter. The causes of the other 14 cases (41.2%) were unknown. 9 cases (26.5%) had clinical manifestations, including respiratory distress, prominent heart murmur, sepsis and limb ischemia. 20 cases (58.8%) showed no clinical features. No data on the other 5 cases (14.7%). 21 cases (61.8%) received vascular intervention removal, 11 cases (32.4%) received surgical removal, 1 case (2.9%) was removed with tweezers, and 1 case (2.9%) died before UVC was removed. Among the neonates receiving surgical treatment, 1 case died of sepsis on the second day after surgery and 1 case had sequela of limb ischemia. 2 cases had postoperative vasospasm and embolism after vascular intervention with overall good prognosis.Conclusions:The rupture of UVC in neonates is rare and mainly related with knife and scissors injury.

Current progression of bevacizumab in advanced non-small cell lung cancer / 中华肿瘤杂志

Non-small cell lung cancer (NSCLC) is one of the malignant diseases with high morbidity, high mortality and poor prognosis in China and worldwide, and the progression of which is significantly related to abnormal angiogenesis. Bevacizumab, a monoclonal antibody targeting vascular endothelial growth factor (VEGF), inhibits angiogenesis during tumor progression. It has been widely demonstrated to improve the survival of NSCLC patients. Therefore, bevacizumab is approved and recommended as the first-line treatment of advanced NSCLC by a number of countries and regions. In this paper, various large-scale clinical trials are analyzed to highlight the current clinical applications of bevacizumab in advanced NSCLC, especially patients with EGFR mutations. In addition, this review focuses on the efficacy, safety and predict factors of bevacizumab as anti-angiogenic therapy, in order to screen the patients who can acquire the maximal benefit.

Investigation of sagittal root position in relation to the anterior maxillary alveolar bone: a cone-beam CT study in 300 cases with normal occlusion / 中华口腔医学杂志

Objective@#To investigate the sagittal root position and apical bone height of the maxillary anterior teeth in order to provide anatomical information for immediate implant placement in the esthetic region.@*Methods@#Cone-beam CT (CBCT) data from 300 randomly selected patients who met the inclusion criteria were included in this study. After three-dimensional reconstruction, the sagittal plane (the sagittal plane through the long axis of the tooth) was determined. The positions and angulations of the tooth roots were classified with reference to the alveolar process. By comparing the buccal and palatal bone thickness at the mid-root level, the toot positions with reference to the mid-alveolar line were defined and classified as follows, type B (closer to the buccal alveolar surface), type M (midway between the buccal and palatal alveolar surface) and type P (closer to the palatal alveolar surface). By comparing the angulations of the alveolar process with the long axis of the roots, the angulations were classified as follows, type 1 (root apex angulated toward the palatal side or parallel to the alveolus), type 2 (root apex angulated toward the buccal side with the long axis passing posterior to point A) and type 3 (root apex angulated toward the buccal side with the long axis passing anterior to point A). The frequency of each category was counted and the apical bone height was measured. The subjects were divided into three age groups, 19-30 years, 31-50 years and 51-75 years.@*Results@#The overall mean apical bone height of the healthy maxillary central incisors was (9.2±3.0) mm, the lateral incisors was (10.0±2.9) mm and the canine was (8.1±3.1) mm. There was no significant difference in the height of apical bone between central incisors and lateral incisors (P>0.05). There was no significant difference in the height of apical bone between male and female (P>0.05). The height of apical bone in group 31-50 years and 51-75 years were greater than that in group 19-30 years (P<0.05), respectively. The proportion of the maxillary anterior teeth type B, M, P was 98.5% (1 774/1 800), 0.3% (5/1 800) and 1.2% (21/1 800) respectively. The proportion of type 1, 2, 3 was 2.6% (46/1 800), 58.6% (1 055/1 800) and 38.8% (699/1 800) respectively.@*Conclusions@#There was enough apical bone height in the area of maxillary anterior teeth, but the majority of roots positioned more buccally.

Effect of dentin proteoglycans on the stability of resin-dentin bonds against artificial saliva storage / 中华口腔医学杂志

Objective@#To investigate the potential effect of proteoglycans (PG) and glycosaminoglycans (GAG) on the stability of resin-dentin bonds against artificial saliva storage.@*Methods@#Seventy-two extracted molars were used to obtain standard dentin bonding surface, and the specimens were etched for 15 s with 37% phosphoric acid and divided into three groups using a table of random number. Then the three groups undergone different incubating procedures as follow: specimens in chondroitinase ABC (C-ABC) group were incubated with C-ABC, specimens in trypsin (TRY) group were incubated with trypsin, and specimens in the control group were incubated with deionized water. All specimens were incubated at 37 ℃ for 48 h in the oscillators. Then specimens in each group were randomly assigned into three subgroups (n=8) as follows: immediate control subgroup, aging subgroups with artificial saliva storage for 6 months and 12 months. Microtensile bond strength (μTBS), fracture mode, bonding interface morphology and nanoleakage were evaluated.@*Results@#Immediately and with artificial saliva storage for 6 months and 12 mouths, the μTBS of TRY group ([49.04±3.57], [37.01±3.21] and [35.27±3.56] MPa) were significantly higher than those in the control group ([40.71±3.32], [28.87±2.34] and [24.20±2.07] MPa) (P<0.05). The immediate μTBS of C-ABC group ([32.94±2.45] MPa) was significantly lower than that of the control group (P<0.05). While with artificial saliva storage for 6 months and 12 mouths, the μTBS of C-ABC group ([26.46±2.45] and [22.50±2.58] MPa) were no differences with those of the control group (P>0.05). The ratio of cohesive fracture increased with the extension of aging time. Some narrow gaps were found in hybrid layer of the control group with artificial saliva storage for 6 months and 12 mouths.@*Conclusions@#Removal of PG increased the μTBS and durable bonds to dentin, while removal of GAG decreased the μTBS, however, it can be of help to create more durable bonds to dentin.

Effects of epigallocatechin-3-gallate modification on the bonding stability of an etch-and-rinse adhesive to intraradicular dentin / 中华口腔医学杂志

Objective@#To evaluate the effects of epigallocatechin-3-gallate (EGCG) modification on the bonding stability of an etch-and-rinse adhesive to intraradicular dentin, and to find a new strategy to improve the stability of bonding interface. @*Methods@#EGCG was incorporated into Single Bond 2 (SB2) with the concentration of 200 mg/L and 400 mg/L respectively to fabricated experimental adhesives group A and group B, while Single Bond 2 without EGCG was used as control group. Laser scanning confocal microscope (LSCM) and scanning electron microscope (SEM) were used to observe the bacterial biofilm adherent to the surface of the cured adhesive. Micro-Raman spectrum was used to test the degree of conversion (DC) of adhesives. The push-out bond strength of instant testing and aging with thermocycling for 5 000 times were also tested. @*Results@#Group A and group B showed inhibiting effect on the biofilm formation of Enterococcus faecalis and performed better with higher concentration. No significant differences were detected in DC among group A ([69.73±0.68]%), group B ([69.03±1.65]%) and control group ([70.06±1.62]%) (P>0.05), and the immediate push-out bond strength of control group ([10.45±2.00] MPa) was not compromised compared to group A ([10.02±2.03] MPa) and group B ([9.95±3.03] MPa) (P>0.05). After thermocycling for 5 000 times, group A ([7.01±1.39] MPa) and group B ([7.62±1.88] MPa) showed significantly higher push-out bond strength than control group did ([5.08±1.56] MPa) (P<0.05). @*Conclusions@#EGCG modified etch-and-rinse adhesives showed anti-bacterial effect and enhanced bonding stability of intraradicular dentin-adhesive interfaces.

Protective effect of ellagic acid on acute liver injury induced by CCl4 in mice and its mechanism / 吉林大学学报(医学版)

Objective:To explore the protective effect of ellagic acid on the acute liver injury induced by carbon tetrachloride (CCl4) of the mice,and to explore its possible mechanism.Methods:A total of 50 mice were randomly divided into normal control group,model group,low,medium and high doses of ellagic acid groups (n=10).The mice in normal control group and model group were treated with 1% sodium carboxymethyl cellulose solvent by intragastic administration,and the mice in ellagic acid groups were treated with 160,320,and 480 mg·kg-1 ellagic acid by intragastic administration,respectively.After 14 d,the mice in model group and different doses of ellagic acid groups were intraperitoneally injected with 10 mL·kg-1 0.1% CCl4,while the mice in normal control group were intraperitoneally injected with 10 mL·kg-1plant oil.16 h later,all the mice were sacrificed and the body weights and the liver indexes of the mice were detected;the serum levels of alanine transaminase(ALT),aspartate transaminase(AST) were detected;the activities of superoxide dismutase(SOD) and levels of GSH-Px,malonalde hyde(MDA) and catalase(CAT) in liver tissue of the mice were detected.Results:There were no significant differences of the body weights of the mice between each group before and after treatment(P>0.05).Compared with normal control group,the liver indexes and the levels of serum ALT and AST of the mice in model group and different doses of ellagic acid groups were significantly increased (P<0.05).Compared with model group,the liver indexes of the mice in different doses of ellagic acid groups were decreased(P<0.05);the serum levels of ALT and AST of the mice in high dose of ellagic acid group were significantly decreased (P<0.05),while the CAT level in liver homogenate was significantly increased (P<0.05);the levels of GSH-Px in liver homogenate of the mice in medium and high doses of ellagic acid groups were significantly increased (P<0.05);the activities of SOD in liver homogenate of the mice in different doses of ellagic acid groups were significantly increased (P<0.05),and the MDA levels were significantly decreased (P<0.05).Conclusion:The ellagic acid has the protective effect on acute chemical liver injury in the mice induced by CCl4 and the most effective dose is 480 mg·kg-1;its mechanism may be related to the anti-oxidation.

Clinical outcomes of implant-retained overdentures:A retrospective study / 实用口腔医学杂志

Objective:To evaluate the clinical outcomes of implant-retained overdentures.Methods:57 patients treated by implant-retained overdentures were included.Parameters for peri-implant tissue conditions (e.g.peri-implant probing depth,plaque index,bleeding on probing,mucosal hyperplasia,peri-implant marginal bone loss) and prosthetic complications were examined and recorded.The precentage of satisfaction of the patients was assessed using the visual analog scale (VAS).Results:After an average follow-up of (48±11.3) months,the survival rate of the implants was 98.1%,the marginal bone loss was (1.38±0.74) mm.There was no statistically difference among the different attachment groups(bar,magnet and ball) regarding the peri-implant marginal bone loss or bleeding on probing(P>0.05).The peri-implant probing depth and plaque index in patients with magnet and ball attachments were lower than those in patients with bar attachments(P0.05),except that magnet and ball attachments were much easier to clean compared with bar attachments(P<0.05).Conclusion:Implant-retained overdenture is a successful and satisfactory treatment option for patients with edentulous jaw.The patients should been given regular clinical examinations to keep peri-implant tissue health and reduce the complications,especially those with bar attachments.

The effects of EGCG and EGCG-3Me on the bonding stability of dentin-adhensive to intraradicular dentin / 实用口腔医学杂志

Objective:To evaluate the effect of epigallocatechin-3-gallate (EGCG) and epigallocatechin-3-O-(3-O-methyl)-gallate (EGCG-3Me) on the anti-bacterial effect and the stability of intraradicular dentin-adhesive interface.Methods:EGCG and EGCG3Me with the concentration of 400 μg/ml were incorporated into Single Bond 2 (SB2) respectively to obtain 2 modified adhesives E-SB2 and E3-SB2.Confocal laser scanning microscopy(CLSM) and ultraviolet spectrophotometry were used to evaluate the anti-bacterial effect of the modified adhesives.Micro-Raman spectrum was used to test the degree of conversion (DC) of the adhesives.Push-out bond strength test was conducted to examine the immediate bond strength and the bond strength after themocycling.Results:E-SB2 and E3-SB2 both showed inhibiting effect on the proliferation of E.faecalis,while E3-SB2 performed stronger inhibiting effect.DC and the immediate push-out bond strength of SB2 were not decreased with the incorporation of EGCG or EGCG-3Me(P ＞ 0.05).E-SB2 and E3-SB2 showed significantly higher push-out bond strengths than that of SB2 (P ＜ 0.05) after themocycling.Conclusion:EGCG and EGCG-3Me modified adhesives have anti-bacterial effect and can enhance the stability of bonding between intraradicular dentin and adhesive,EGCG-3Me may have stronger anti-bacterial effect.

Analysis of type-I collagen fibrils and chondroitin sulfate distribution in human dentin by confocal laser scanning microscopy combined with dual immunofluorescent labeling technique / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To introduce the method of dual immunofluorescence labeling of human dentin matrix without demineralization of the whole dentin fragments, and to analyze the distribution of type-I collagen fibrils and chondroitin sulfate in human dentin.</p><p><b>METHODS</b>Forty 30 µm- thick middle coronal dentin sections were obtained from 8 freshly extracted human third molars and etched with 37% phosphoric acid(PA) gel for 15 s. After preconditioning with or without tosyl- phenylalanyl chloromethyl ketone(TPCK) treated trypsin digestion, sections were subjected to dual immunofluorescent labeling and scanned by confocal laser scanning microscopy to identify the type-I collagen fibrils and chondroitin sulfate.</p><p><b>RESULTS</b>Chondroitin sulfate was localized in the lumens of the dentin tubules and peritubular dentin, while the type-I collagen fibrils were localized in intertubular dentin and peritubular dentin. After preconditioning with TPCK treated trypsin digestion, the red fluorescence was decreased or disappeared.</p><p><b>CONCLUSIONS</b>The dual immunofluorescence labeling methodology can be used to study the human dentin matrix without demineralization of the whole dentin fragments. Chondroitin sulfate was localized in the lumens of the dentin tubules and peritubular dentin, while the type-I collagen fibrils were localized in intertubular dentin and peritubular dentin.</p>

Preparation and property analysis of a novel dental lithium disilicate glass-ceramic / 实用口腔医学杂志

Objective:To prepare a novel dental lithium disilicate glass-ceramic,and to study its properties.Methods:A2 colored novel glass-ceramic was prepared by sintering technique.The flexural strength,density,elastic modulus,hardness,fracture toughness, translucency and microstructure of the novel glass-ceramic and IPS e.max Press (LT A2,MO1 and HO1 )ceramic ingots were studied. Results:The novel glass-ceramic demonstrated a lower flexural strength (31 5 MPa)than MO ceramic ingot(338 MPa)(P 0.05).The translu-cency parameter of the novel glass-ceramic(21 .2)was higher than that of HO(1 6.5)but lower than that of LT(27.8)and MO(27.5) ceramic ingots(P <0.05).SEMimages showed an interlocking microstructure of rod-shaped Li2 Si2 O5 crystals in all the glass-ceramics investigated.Conclusion:The mechanical properties,translucency and microstructure of the novel glass-ceramic are similar to those of IPS e.max Press ceramic ingots,which can meet the requirements of clinical application.

New fixation set-up designed for micro-tensile test / 实用口腔医学杂志

Objective:To introduce a new fixation set-up for micro-tensile test.Methods:Dentin-composite were bonded with AdperTM Single Bond 2 (SB2)and sectioned into stick-shaped specimens.Specimens from each tooth(n =6)were equally divided into Ciucchi's jig and the designed set-up(Control and experimental)groups for micro-tensile bond test according to the utilized fixa-tion set-up.The bonding interface failure mode was examined with field-emission scanning electron microscope (FESEM).Three-dimensional models of the two set-ups and the specimen were developed,stress distribution was analyzed by finite element analysis (FEA).Results:The bond strength(MPa)of experimental and control group was 32.76 ±7.43 and 43.58 ±4.72(P <0.05),the ratio of mixed failure was 28 /36 and 20 /36(P <0.05)respectively.FEA showed that the designed set-up for fixing the sticks pro-vided a uniform stress distribution along the long axis of the specimen.FEA and failure mode analysis confirmed such uniform distri-bution was also concentrated at the bonding interface.Conclusion:The new set-up is feasible for micro-tensile test.

Quantitative detection of matrix metalloproteinase-2 in normal coronal dentine of young people / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To compare the distribution and concentration of matrix metalloproteinases-2 (MMP-2) in different dentin depth of premolar and molar of young people.</p><p><b>METHODS</b>Freshly extracted human premolars and molars (aged between 20-30) were sectioned to 1.5 mm thick slices along the longitudinal axis of the tooth separately. Enamel and pulp of each slice was removed, and then the premolar and molar slices were respectively divided into two subgroups according to superficial or deep dentin and pulverized to fine powder. After dentin protein was extracted, the concentrations of MMP-2 in different tooth were detected using fluorescent microsphere immunoassay.</p><p><b>RESULTS</b>The content of MMP-2 in superficial layer dentin of premolar was (0.022 ± 0.006) ng/mg. The content of MMP-2 in deep layer dentin of premolar was (2.087 ± 0.090) ng/mg. The content of MMP-2 in superficial layer dentin of molar was (0.336 ± 0.037) ng/mg. The content of MMP-2 in deep layer dentin of molar was (3.312 ± 0.308) ng/mg.</p><p><b>CONCLUSIONS</b>MMP-2 exists in human coronal dentin. In the same type of teeth of young people, the concentration of MMP-2 in deep dentin was significant higher than those in superficial dentin. In the same dentin depth, the concentration of MMP-2 in molar was significant higher than those in premolar.</p>

Effect of three aging challenges on the bonding stability of resin-dentin interface using an etch-and-rinse adhesive / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To systematically investigate the aging effect of thermocycling, water storage and bacteria aggression on the stability of resin-dentin bonds.</p><p><b>METHODS</b>Forty molars were sectioned perpendicularly to the axis of the teeth to expose the middle-coronal dentin surfaces. The dentin surfaces were then treated with Single Bond 2 and made a core build-up. According to random digits table, the bonding specimens were divided into four groups (n = 10) as follows: immediate control group, aging group with thermocycling for 5 000 times, aging group with artificial saliva storage for 6 months and aging group with bacteria aggression for 14 days. The specimens in each group were then subjected to microtensile bond strengths (µTBS) testing and nanoleakage evaluation respectively.</p><p><b>RESULTS</b>After aging treatments, the three aging groups showed significantly lower µTBS than the immediate control group [(44.24 ± 12.75) MPa, P < 0.05]. The immediate control group also showed the lowest value of nanoleakage. The µTBS of aging group with bacteria aggression [(25.53 ± 7.39) MPa] was significantly lower than those of the other aging groups with artificial saliva storage[(29.72 ± 6.51) MPa] and thermocycling [(31.92 ± 11.87) MPa, P < 0.05]. There were no differences in the nanoleakage values among the three aging groups (P > 0.05).</p><p><b>CONCLUSIONS</b>All the aging treatments with artificial saliva storage, thermocycling and bacteria aggression could accelerate the degradation of bonding interfaces between an etch-and-rinse adhesive and dentin. Bacteria aggression showed the most impairing effect on the stability of resin-dentin bonds.</p>

Study of the types of matrix metalloproteinases involved in dentin bonding interface degradation / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the types of matrix metalloproteinases (MMPs) involved in dentin bonding interface degradation.</p><p><b>METHODS</b>Dentin slices were prepared and treated with two adhesive systems (Single Bond 2 or Clearfil S3 Bond). The dentin surface was bonded with composite resin. All specimens were immersed in sterile artificial saliva for 0 or 6 months, and their micro-shear bond strength (muSBS) were measured. The fracture modes were observed through field emission scanning electron microscope (FE-SEM). Dentin slices with 4 mm x 3 mm x 1 mm dimensions were prepared. The slices were divided into three groups according to the treatment modes (negative control, Single Bond 2, and Clearfil S3 Bond). All specimens were stored in sterile artificial saliva for 0 or 6 months. The concentrations of MMP-1, -2, -3, -8, and -9 of each group were detected through fluorescent microsphere immunoassay.</p><p><b>RESULTS</b>The muSBS of both adhesive systems significantly decreased after storage aging. Significant differences in failure modes within the four groups tested in this study were observed. Compared with the negative control, the concentrations of MMP-1 and MMP-3 in different adhesive groups showed no significant difference after storage aging. However, the concentrations of MMP-2, -8, and -9 in Single Bond 2 group and the concentrations of MMP-8 and -9 in Clearfil S3 Bond group significantly decreased after 6 months of storage aging.</p><p><b>CONCLUSION</b>Significant degradation occur in the dentin bonding interface of both adhesive groups under 6 months aging challenge. The concentrations ofdentinal MMP-2, -8, and -9 significantly decrease after treatment with adhesives and aging, indicating that these MMPs have an important function in dentin bonding interface degradation.</p>

Effect of dentin proteoglycans on the bonding properties of dentin / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the potential effect of proteoglycan (PG) and glycosaminoglycan (GAG) on the bonding of etch and rinse adhesive to dentin, in order to improve the bonding effect of dentin.</p><p><b>METHODS</b>Forty-two extracted molars were used to obtain standard dentin bonding surface, and the specimens were etched for 15 s with 37% phosphoric acid and divided into three groups using a table of random numbers. Then the three groups undergone different incubating procedures as follow: specimens in chondroitinase ABC (C-ABC) group were incubated with C-ABC at 37 °C for 48 h in vibrator. Specimens in trypsin (TRY) group were incubated with trypsin, and specimens in the control group were incubated with deionized water for 48 h in the oscillators. Then specimens in each group were randomly assigned into two subgroups, A (Adper(TM) Single Bond 2) and B (Prime & Bond NT) (n = 7). The microtensile bond strength (µTBS), fracture mode and bonding interface morphology of the specimens were evaluated via microtensile testing, stereo microscope and field emission scanning electron microscopy (FE-SEM) respectively after specimens being incubated in 37 °C water for 24 h.</p><p><b>RESULTS</b>The immediate µTBS of C-ABC group bonding with adhesive A and B [(32.9±2.5) and (26.8±2.2) MPa] were significantly lower than that of the control group [(40.7±3.3) and (34.6±3.7) MPa] (P < 0.05). While the immediate µTBS of TRY group [(49.0 ± 3.6) and (44.5 ± 3.0) MPa] were significantly higher than that of the control group(P < 0.05).</p><p><b>CONCLUSIONS</b>Dentin PG participates in the dentin bonding process. Removal of PG increased the immediate µTBS of dentin and total etching adhesives, while removal of GAG decreased the immediate µTBS.</p>

Localization and quantitative detection of matrix metalloproteinase in human coronal dentine / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To compare the distribution and concentrations of matrix metalloproteinase (MMP)-1, 2, 3, 8, 9 in human coronal dentin.</p><p><b>METHODS</b>The localization of five types of MMP was performed using immunohistochemistry. Molars were demineralized and sectioned into 5 µm thick specimens. All specimens were randomly divided into five groups according to the antibodies. Each group contained two subgroups (n = 6). Immunoreactivity of each subgroup was visualized with 3, 3-diaminobenzidine solution or fluorescein isothiocyanate and observed under microscopy respectively. Molars were sectioned into slices. The slices were divided into two groups according to superficial or deep dentin and pulverized to fine powder. After dentin protein was extracted, the concentrations of MMP-1, 2, 3, 8, 9 were detected by using fluorescent microsphere immunoassay.</p><p><b>RESULTS</b>Immunohistochemical staining revealed that MMP-1, 2, 3, 8, 9 were highly concentrated in the deep dentin. However, intense immunoreactivities of MMP-2, 8, 9 were identified in a 6-10 µm wide zone adjacent to the dentino-enamel junction. The content of MMP-1 in superficial layer and deep layer of dentin were (0.037±0.025) and (0.433±0.089) ng/mg. The content of MMP-2 in superficial layer and deep layer of dentin were (0.445±0.115) and (2.730±0.712) ng/mg. The content of MMP-3 in superficial layer and deep layer of dentin were (0.071±0.069) and (0.460±0.108) ng/mg. The content of MMP-8 in superficial layer and deep layer of dentin were (0.586±0.246) and (6.159±0.948) ng/mg. The content of MMP-9 in superficial layer and deep layer of dentin were (0.384±0.185) and (1.460±0.251) ng/mg. The concentrations of all tested MMP were significantly higher in deep dentin than those in superficial dentin (P < 0.05).</p><p><b>CONCLUSIONS</b>There are five types of MMP contained in human coronal dentin, and the distribution of MMP shows a decreasing trend from the deep dentin to the superficial dentin.</p>

Bonding properties of four different cements to glass fiber posts after different treatments / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of four different cements on the bonding effectiveness of root canal dentine and fiber post before and after different treatments.</p><p><b>METHODS</b>A total of 216 freshly extracted sound single-root-canal mandibular premolars were randomly divided into four groups. After root canal treatment and post space preparation being conducted on the premolars, Fuji I, Fuji Cem, RelyX Unicem, RelyX ARC were used respectively to bond fiber posts and were marked with group A, B, C, and D. Microleakage, micromorphology of the bonded interfaces, and pull-out bond strength were evaluated in the immediate group, thermocycling group and thermomechanical loading group.</p><p><b>RESULTS</b>In the immediate group, samples in group D showed the highest bond strength [(278 ± 26)N], followed by group C[ (219 ± 12) N], B[ (104 ± 23) N] and A[(73 ± 8) N]. Significant differences were found among all groups (P < 0.05) . A significant increase in bond strength was found in group A and B, whereas a decrease tendency was detected in group C and D after different treatments.Scanning electron microscope indicated that some little gaps were observed in group D after treatment, while a more intense bonding interface was found in group A and B. Microleakage scores in group A and B were lower than those in group C and D after aging treatments.</p><p><b>CONCLUSIONS</b>Resin cement can achieve a better immediate bond strength, while resin-modified resin cement may acquire a better long-term retention.</p>

Effect of casein phosphopeptide-amorphous calcium phosphate on the stability of resin-dentin bonds against pH cycling / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on the stability of resin-dentin bonds against pH cycling.</p><p><b>METHODS</b>Resin-bonded dentin specimens were prepared following manufacturers' instructions, and randomly divided into 3 groups. Among them, 2 groups experienced pH cycling, in which specimens applied CPP-ACP or distilled and deionized water (DDW) on the bonding interface, respectively. Microtensile bond strength (muTBS) testing, failure mode analysis, micromorphological and nanoleakage evaluation of bonding interface and elemental analysis within hybrid layer were performed after 15 days pH cycling. The other group was tested immediately after specimens' preparation without pH cycling.</p><p><b>RESULTS</b>No significant differences were found in muTBS between no pH cycling and pH cycling/CPP-ACP group. Their muTBS were both significantly higher than that of pH cycling/DDW group (P < 0.05). Mixed fractures were the most prevalent failure mode. The quality of hybrid layer in pH cycling/CPP-ACP group was better than that of pH cycling/DDW group, and the nanoleakage was also less severe. Comparing with pH cycling/DDW group, the atomic percentages of Ca in the other two groups were both significantly higher, while those of Ag were statistically lower (P < 0.05).</p><p><b>CONCLUSION</b>Local application of CPP-ACP can promote the stability of resin-dentin bonding interface against pH cycling and prolong bonding degeneration.</p>

Emergency surgical treatment of hemoptysis / 中国基层医药

Objective To explore discussion medical treatment in massive hemoptysis emergency surgical treatment.Methods Hemorrhage parts,timing of surgery,pneumonectomy scope in 24 cases of massive hemoptysis were analyzed.Results 24 cases of massive hemoptysis emergency surgical treatment were successful,no death and complication rate was 8.3% (2/24).Conclusion For medical treatment ineffective massive hemoptysis determine the location of the bleeding,actively carry out preoperative preparation, choosing the best opportunity emergency resection of lung disease,can be effective in reducing mortality.

Corrective therapy for different kinds of open bite malformations / 中华医学美学美容杂志

Objective To investigate the effects of a corrective tr ea tment on open bite malformations, such as gnash their teeth, nail-biting, tongu e thrusting, impacted tooth, cross bite with improper correction, open bite defo rmity resulted from premature shedding of deciduous tooth and molar cysts. Methods We used dental resin technology: acid etching the teeth, adh ering metal clasps to the teeth by means of composite resin, and applying elasti c bands for intermaxillary traction to correct the cross bite. Results We had treated 22 patients, age ranged from 7-30, with the malformatio ns resulted from different kinds of reasons, and obtained significant results. Conclusion With cooperation of the patients, simple corrections for open bite with sticky clasp and occlusion with elastic band are easy to car ry on, with short period of treatment time, and every patient gets prominent out come. It is effective, prior to commonly-used corrective therapy and deserves t o be widely used.