The positive impact of Streptococcus mutans on the growth of Candida albicans within mixed-species biofilms and implications to dental health.

INTRODUCTION: Candida albicans and Streptococcus mutans co-exist in biofilms in the oral cavity. In this study, the impact of S. mutans on the growth of C. albicans within a mixed-species biofilm was examined. MATERIALS AND METHODS: Single species C. albicans biofilms and mixed species biofilms containing C. albicans and S. mutans at 1:3 and 1:10 ratios were constructed in 6-well microtiter plates. After 24 hours of incubation, the density of resuspended biofilm cells was determined as CFU/ml and used to compare the growth of C. albicans in single species and mixed species biofilms. RESULTS: The CFU/ml of C. albicans in mixed-species biofilms was found to be higher than that in single-species biofilms. CONCLUSION: S. mutans promotes the growth of C. albicans in a co-inhabited biofilm.

[A real-world study on the efficacy and safety analysis of paclitaxel liposome in advanced breast cancer].

Objective: To explore the application and efficacy of paclitaxel liposome in the treatment of advanced breast cancer among Chinese population in the real world. Methods: The clinical characteristics of patients with advanced breast cancer who received paclitaxel liposome as salvage treatment from January 1, 2016 to August 31, 2019 in 11 hospitals were collected and retrospectively analyzed. The primary outcome was progression free survival (PFS), and the secondary outcome included objective response rate (ORR) and safety. The survival curve was drawn by Kaplan-Meier analysis and the Cox regression model were used for the multivariate analysis. Results: Among 647 patients with advanced breast cancer who received paclitaxel liposome, the first-line treatment accounted for 43.3% (280/647), the second-line treatment accounted for 27.7% (179/647), and the third-line and above treatment accounted for 29.1% (188/647). The median dose of first-line and second-line treatment was 260 mg per cycle, and 240 mg in third line and above treatment. The median period of paclitaxel liposome alone and combined chemotherapy or targeted therapy is 4 cycles and 6 cycles, respectively. In the whole group, 167 patients (25.8%) were treated with paclitaxel liposome combined with capecitabine±trastuzumab (TX±H), 123 patients (19.0%) were treated with paclitaxel liposome alone (T), and 119 patients (18.4%) were treated with paclitaxel liposome combined with platinum ± trastuzumab (TP±H), 108 patients (16.7%) were treated with paclitaxel liposome combined with trastuzumab ± pertuzumab (TH±P). The median PFS of first-line and second-line patients (5.5 and 5.5 months, respectively) were longer than that of patients treated with third line and above (4.9 months, P<0.05); The ORR of the first line, second line, third line and above patients were 46.7%, 36.8% and 28.2%, respectively. Multivariate analysis showed that event-free survival (EFS) and the number of treatment lines were independent prognostic factors for PFS. The common adverse events were myelosuppression, gastrointestinal reactions, hand foot syndrome and abnormal liver function. Conclusion: Paclitaxel liposomes is widely used and has promising efficacy in multi-subtype advanced breast cancer.

[Characteristics and microRNA expression profile of exosomes derived from odontogenic dental pulp stem cells].

OBJECTIVE: To investigate the characteristics of exosomes derived from dental pulp stem cells (DPSCs) in the direction of odontogenic differentiation, to analyze the differences in microRNA expression profile between exosomes derived from undifferentiated and odontogenic DPSCs, and to analyze their possible signal transduction pathways. METHODS: (1) DPSCs were cultured in α minimum Eagle' s medium (α-MEM), and odontogenic DPSCs were cultured in odontogenic differentiation medium for 21 days, using alizarin red staining and alkaline phosphatase staining to identify the odontogenic differentiation. Exosomes from the cell supernatant were isolated respectively, named as dental pulp stem cells-exosomes (DPSCs-Exo) and dental pulp stem cells-odontogenic-exosomes (DPSCs-OD-Exo). The exosomes were identified by transmission electron microscopy, nanoparticle tracking analysis and Western blot. (2) The microRNA expression profiles of DPSCs-Exo and DPSCs-OD-Exo were investigated by microRNA microarray. To validate the result of the microRNA microarray, real-time quantitative polymerase chain reaction (real-time PCR) assay was applied on 3 most significantly differential expressed microRNA. Pathway analysis was taken to detect enriched pathways associated with the predicted target genes of microRNA. RESULTS: (1) The DPSCs were isolated and cultured in vitro showed typical fibroblast-like morphology. The odontogenic differentiated DPSCs were spindle-shaped, polygonal, and uniform in size. Odontogenic differentiation group showed a large number of dark deposits in alizarin red staining and the cells were darkly stained in alkaline phosphatase staining, while the cells in normal culture medium group did not show obvious dyeing. The DPSCs-Exo and DPSCs-OD-Exo had the same morphology, both showed bilayer membrane and cup-shape. The peak sizes of DPSCs-Exo and DPSCs-OD-Exo were (114.67±9.07) nm and (134.00±8.54) nm, respectively. The difference between the two was statistically significant. DPSCs-Exo and DPSCs-OD-Exo both expressed the markers of exosomes, tumor susceptibility gene (TSG)101 and CD63. (2) microRNA microarray results showed that the expression profiles of DPSCs-Exo and DPSCs-OD-Exo were different. Nineteen increased by more than two times, and one decreased by 64%. Real-time PCR results showed that the expression levels of microRNA-1246, microRNA-1246-100-5p and microRNA-1246-494-3p in DPSCs-OD-Exo were significantly up-regulated. The difference was statistically significant. microRNA target prediction database and gene signaling pathway database were used to analyze differentially expressed microRNA, and it was predicted that differentially expressed microRNA could target axis inhibition protein 2(AXIN2) gene and Wnt/ß-catenin signaling pathway. CONCLUSION: DPSCs-OD-Exo and DPSCs-Exo had differences in their microRNA expression profile. Those differentially expressed microRNA may be involved in the regulation of DPSCs odontogenic differentiation.

[Effect of various intracanal materials on the diagnostic accuracy of cone-beam computed tomography in vertical root fractures].

OBJECTIVE: To study the effect of various intracanal materials on the accuracy of oral maxillofacial cone-beam computed tomography (CBCT) for the diagnosis of vertical root fracture (VRF). METHODS: A total of twenty-four structurally intact single root canal dried and isolated teeth extracted for orthodontic treatment or periodontal disease were collected. The teeth were decrowned along the cemento-enamel junction (CEJ) and then used as samples for the study after conventional root canal preparation and post preparation. The 24 samples were divided into two groups with 12 samples in each group. Group A was the control group (no VRF group). According to intracanal materials, they were divided into five subgroups: blank group, fiber post group, gutta-percha point group, titanium post group and gold-palladium post group. Group B was the experimental group (VRF group), and subgroups were grouped as above. The VRF model was prepared by a unified method in the VRF group: the root was completely fractured in the buccolingual direction with a custom root canal nail and then cemented and reset. The control group was not subjected to the simulation of VRF. Titanium post and gold-palladium post were made according to the individuality of the root canal preparation, and the tightness of the post to the root canal wall was confirmed by X-ray radiograph. Then all the samples were scanned by CBCT in the isolate swine mandibular alveolar sockets. The diagnostic accuracy was statistically analyzed via blind interpretation by experienced endodontic specialists and oral and maxillofacial medical imaging specialists. RESULTS: The accuracy of the diagnosis of VRF in the blank group, fiber post group, gutta-percha point group, titanium post group, and gold-palladium post group in CBCT was 95.83%, 91.67%, 87.50%, 79.17%, and 45.83%, respectively. Compared with the blank group, the differences were not statistically significant in the fiber post group (P>0.999), the gutta-percha point group (P=0.500) and the titanium post group (P=0.125). The lowest diagnostic accuracy of VRF was found in the gold-palladium post group, and the difference was statistically significant compared with all other groups (P < 0.001). CONCLUSION: Various intracanal materials have different degrees of influence on the diagnostic accuracy of VRF diagnosis in CBCT. The influence of fiber post, gutta-percha point and titanium post was small, while the influence of gold-palladium post was significant.

[A long-term evaluation of periodontal phenotypes before and after the periodontal-orthodontic-orthognathic combined treatment of lower anterior teeth in patients with skeletal Angle class â ¢ malocclusion].

OBJECTIVE: To evaluate the changes of periodontal phenotype (width of keratinized gingiva, thickness and height of alveolar bone) of lower anterior teeth in patients with skeletal class Ⅲ malocclusion before and after the periodontal-orthodontic-orthognathic combined treatment. METHODS: In the study, 20 patients with skeletal class Ⅲ malocclusion (6 males and 14 females) completed the periodontal-orthodontic-orthognathic combined treatment were included from March 2017 to June 2022, with 39 central incisors, 40 lateral incisors and 40 canines. The mean age was (25.40±4.27) years (20-34 years). The mean follow-up time was (3.70±1.05) years from the beginning of periodontal corticotomy regenerative surgery (PCRS) to the end of the combined treatment. Cone-beam computed tomography (CBCT) was used to measure the thickness, area and height of alveolar bone by the same researcher, taken before the PCRS (T0), 6 months after the PCRS (T1), 12 months after the PCRS (T2), before the orthognathic surgery (T3), and after the periodontal-orthodontic-orthognathic combined treatment (T4). The periodontal clinical parameters were used to evaluate changes in the soft tissue by another researcher, measured before the PCRS (T0) and after the combined treatment (T4). Changes of soft and hard tissue were evaluated by the periodontal phenotype. RESULTS: The width of keratinized gingiva increased significantly (all P < 0.001) in lower anterior teeth, the central incisors, lateral incisors and canines increased by (1.82±1.57) mm, (2.03±1.48) mm and (2.05±1.27) mm, respectively. The proportion of thick periodontal biotype in the central and lateral incisors increased significantly (all P < 0.001), while the changes of periodontal biotypes in the lower canines were not obvious. The thickness of labial alveolar bone of lower anterior teeth all increased significantly after periodontal corticotomy regenerative surgery and the combined treatment (all P < 0.001). The area of labial alveolar bone of lower anterior teeth also increased significantly after the combined treatment (all P < 0.001). The whole area of labial and lingual alveolar bone of central and lateral incisors increased (P < 0.001), while the whole area of canines remained the same. All The height of the alveolar bone increased (all P < 0.001) on the labial side after the treatment. CONCLUSION: The periodontal phenotypes of lower anterior teeth were significantly improved after the periodontal-orthodontic-orthognathic combined treatment in patients with skeletal Angle class Ⅲ malocclusion. The improvement was long-termly stable, and the periodontal risk was reduced.

[Imaging study on determining the rationality of atlantoaxial fixation angle based on the ratio of line segments between anatomical markers on lateral X-ray films].

Objective: To propose a method to determine the unreasonableness of the fixed angle in posterior atlantoaxial fusion surgery based on the ratio of line segments between anatomical landmarks of the atlantoaxial joint. Methods: A cross-sectional study was conducted. According to the inclusion criteria, a screening was performed on the database of asymptomatic volunteers who had full-spine lateral X-ray films taken at the Second Affiliated Hospital of Wenzhou Medical University from May 2016 to May 2021. A total of 207 volunteers were included, comprising 98 males with an age of (40.68±13.87) years and 109 females with an age of (42.64±14.45) years. On the lateral X-ray film, a line (L) parallel to the posterior margin of the odontoid process was drawn at the posterior edge of the lower articular surface of the axis (a), intersecting the atlas at points b, c, and d. The line segments ab, bd, bc, and the C1-C2 angle were measured, and the ratios of bd/ab and bc/ab were calculated. The ability of bd/ab and bc/ab to predict the unreasonable fixed angle of the atlantoaxial joint (≥22°) was analyzed by receiver operating characteristic (ROC) curve analysis in both male and female. The areas under the ROC curves (AUC) were calculated, and the performance of the two prediction methods was compared using the Delong's test. The cutoff value for distinguishing the unreasonableness of the C1-C2 angle and the sensitivity and specificity were calculated. Results: The ROC curve analysis in the male group showed that the AUC of bc/ab for predicting the unreasonable C1-C2 angle was 0.791 (95%CI: 0.696-0.867, P<0.001), with a cutoff value of 0.449, sensitivity of 97.3%, and specificity of 70.0%. The performance was significantly better than that of bd/ab (cutoff value 1.100, AUC=0.532, 95%CI: 0.428-0.634, sensitivity 26.3%, specificity 83.3%, P<0.001). The ROC curve analysis in the female group showed that the AUC of bc/ab for predicting the unreasonable C1-C2 angle was 0.804 (95%CI: 0.745-0.852, P<0.001), with a cutoff value of 0.488, sensitivity of 90.5%, and specificity of 58.6%. The performance was significantly better than that of bd/ab (cutoff value 0.960, AUC=0.687, 95%CI: 0.624-0.748, sensitivity 90.5%, specificity 44.8%, P=0.041). Conclusions: The bc/ab value can be used as an effective indicator to predict the unreasonable C1-C2 angle in posterior atlantoaxial fusion surgery with high diagnostic accuracy. The cutoff value for males is<0.449, and for females is<0.488.

Chrysin induces osteogenic differentiation of human dental pulp stem cells.

OBJECTIVES: As an ideal cell source for tissue engineering and bone defect repair, dental pulp stem cells (DPSCs) have good osteogenic differentiation potential. Chrysin, a flavonoid extracted from oroxylum seeds, has been proven to promote bone formation of bone marrow stem cells. However, the effect of chrysin on osteogenic differentiation of DPSCs remains unclear. This study aimed to investigate the role of Chrysin in promoting osteogenic differentiation of DPSCs and in DPSC-based bone formation. MATERIAL AND METHODS: We investigated the effects of chrysin on DPSCs from patients by CCK-8 assay, Alizarin Red S staining, qPCR and Western blotting. The effects of chrysin on DPSC-based bone formation in a heterotopic osteogenesis model in nude mice and a rat calvarial defect model were also performed. Finally, we investigated the mechanism of chrysin-treated DPSCs by proteomics. RESULTS: Chrysin upregulated the expression of osteogenic proteins and induced osteogenic differentiation of DPSCs. Moreover, chrysin induced abundant ß-TCP-induced formation of mineralized bone tissue and promoted DPSC-based bone formation in a heterotopic osteogenesis model in nude mice and a rat calvarial defect model. Proteomics showed that upregulation of the Smad3 was closely related to osteogenic differentiation. Inhibiting of Smad3 activation by a Smad3 inhibitor could reverse the chrysin-mediated increases in the expression levels of osteogenic genes and osteogenic induction of DPSCs. CONCLUSIONS: Our study implies the intriguing potential of chrysin-treated DPSCs in bone regeneration and bone defect repair.

[Surface roughness, gloss and sequential polishing times of various chairside computer aided design/manufacturing restorative materials].

OBJECTIVE: To investigate the effect of polishing on surface roughness, gloss and optimum polishing time of various computer aided design/computer aided manufacturing (CAD/CAM) restorative materials and to provide a proper polishing procedure for dental clinicians. METHODS: Five CAD/CAM restorative materials including vita mark Ⅱ (VM), vita enamic (VE), lava ultimate (LU), shofu block HC (SB) and brilliant crios (BC) were selected. Six specimens were prepared for each material. The specimen was fixed on a custom-made polishing apparatus and sequentially polished with Sof-Lex poli-shing disk system including medium disk (with abrasive particle sizes of 10-40 µm), fine disk (with abrasive particle sizes of 3-9 µm) and superfine disk (with abrasive particle sizes of 1-7 µm). Surface roughness (Ra value) and gloss value were measured every 10 seconds until the numerical values were no longer changed. Then the surface roughness, gloss value and polishing time were recorded and the specimen was moved to the next sequence of polishing. Finally, statistical analysis was performed using SPSS 24.0. RESULTS: For all the restorative materials, the Ra values were significantly reduced (P < 0.05) and the gloss values were significantly increased (P < 0.05) after sequentially polishing with Sof-Lex disks. No significant difference was detected among Ra values of all the tested materials (P>0.05) after sequential polishing. The gloss values of LU [(68.1±4.5) GU] and BC [(68.2±5.8) GU] were significantly higher than those of VE [(48.1±8.1) GU] and BC [(53.2±5.8) GU], P < 0.05. To obtain optimal surface smoothness, VM cost the shortest polishing time [40 (30, 55) s] among all the restorative materials (P < 0.05). No significant differences in the total polishing time were observed among VE [140 (135, 145) s], LU [130 (120, 140) s], SB [140 (130, 150) s] and BC [130 (120, 140) s], P>0.05. CONCLUSION: The surface roughness of all CAD/CAM restorative materials were decreased after sequentially polishing with Sof-Lex disk system. To obtain the smoothest surface, different types of restorative materials might need different polishing times using Sof-Lex polishing disk system. For ceramic restorative material VM, we recommend polishing only with medium disk for 40 s. For hybrid restorative material VE and composite restorative material LU, SB and BC, we recommend polishing with medium disk, fine disk and superfine disk in sequence for 130-140 s in total.

[A cone-beam computed tomography evaluation of three-dimensional changes of circummaxillary sutures following maxillary protraction with alternate rapid palatal expansions and constrictions].

OBJECTIVE: To assess three-dimensional (3D) changes of circummaxillary sutures following maxillary protraction with alternate rapid palatal expansions and constrictions (RPE/C) facemask protocol in maxillary retrusive children, and to investigate the relationship between the changes of circum-maxillary sutures and zygomaticomaxillary suture (ZMS) maturation, and to explore the factors of maxilla forward movement with RPE/C and facemask. METHODS: In the study (clinical trial registration No: ChiCTR2000034909), 36 maxillary retrusive patients were recruited and block randomized to either the rapid palatal expansion (RPE) group or the RPE/C group. Patients aged 7 to 13 years, Class Ⅲ malocclusion, anterior crossbite, ANB less than 0°, Wits appraisal less than -2 mm, and A-Np less than 0 mm were included in the study. The RPE group received rapid palatal expansion, whereas the RPE/C group received alternate rapid palatal expansions and constrictions, and both with facemask protraction. Head orientations of cone-beam computed tomography (CBCT) images were implemented by Dolphin 11.7. 3D measurements of circummaxillary sutures on CBCT images were evaluated using Mimics 10.01 before (T0) and after treatment (T1). The changes were analyzed with independent t test, two-way ANOVA, Pearson correlation and regression analysis. RESULTS: Two subjects in the RPE/C group were lost to follow-up. A total of 34 patients reached the completion criteria and were analyzed. Compared with the RPE group, sagittal changes of circummaxillary sutures were significantly increased in the RPE/C group with 1.21 mm advancement of zygomaticotemporal suture, 2.20 mm of ZMS, 1.43 mm of zygoma-ticofrontal suture (P < 0.05, respectively). Except for the zygomaticotemporal suture, the rest forward sagittal changes of other circummaxillary sutures showed no major difference in terms of the ZMS maturation. The Spearman's correlation in RPE/C indicated a strong positive correlation of sagittal changes between ZMS and point A (P < 0.01) with a regression analysis R2=42.5%. CONCLUSION: RPE/C might be more effective on the treatment of maxillary retrusive children. As one of the major mechanical loading sutures during orthopedic therapy, ZMS showed a strong positive correlation with point A on sagittal changes.

[Effects of the resin base and retention depth on fracture resistance of molars restored with nano-ceramic endocrowns].

OBJECTIVE: To compare the effects of resin base and different retention depth on the fracture resistance of mandibular molars restored with nano-ceramic endocrowns. METHODS: Forty mandibular molars selected and randomly divided into 5 groups: ① The control group which was consisted of intact teeth, ② the non-resin base group, ③ the 2 mm retention depth group, ④ the 3 mm retention depth group, ⑤ the 4 mm retention depth group, respectively. After tooth preparation, in vitro root canal therapy was conducted, which was followed by endocrown design, production and adhesive of groups ②-⑤. All the samples were under load (N) of the universal mechanical testing machine after embedding. The fracture pattern of each sample was observed under stereomicroscope. Then the microstructure of the fracture surface was observed by scanning electron microscopy. RESULTS: The fracture loads of each group were respectively: the control group fracture load was (3 069.34±939.50) N; experimental groups: fracture load of (2 438.04±774.40) N for the group without resin base; fracture load of (3 537.18±763.65) N for the group with 2 mm retention depth. The fracture load of the retention depth 3 mm group was (2 331.55±766.39) N; the fracture load of the retention depth 4 mm group was (2 786.98±709.24) N. There was statistical significance in the effect of resin base and different retention depth on the fracture loads of molars restored with nano-ceramic endocrown (P < 0.05). Repairable fractures in each group were as follows: control group 2/8, non-resin base group 1/8, retention depth of 2 mm group 1/8, retention depth of 3 mm group 2/8, and retention depth of 4 mm group 0/8. The effects of the retention depth and the presence of resin base on the fracture resistance of the resin nano-ceramic endocrowns were statistically significant (P < 0.05). Scanning electron microscopy showed more arrest lines and small twist hackles on the fracture surface of the restorations with resin base (retention depths of 2 mm, 3 mm, and 4 mm), with cracks extending towards the root. In addition to the characteristics above, more transverse cracks parallel to the occlusal surface, pointing outwards from the center of the pulp cavity retention, were also observed on the fracture surface of the non-resin base restorations. CONCLUSION: When molar teeth with nano-ceramic endocrowns are restored, resin base and the retention depth of 2 mm help the teeth to obtain optimal fracture strength.

[Gene polymorphisms of cytochrome B-245 alpha chain (CYBA) and cholesteryl ester transfer protein (CETP) and susceptibility to generalized aggressive periodontitis].

OBJECTIVE: To explore the correlation of cytochrome B-245 alpha chain (CYBA) rs4673 and cholesteryl ester transfer protein (CETP) rs12720922 polymorphisms with the susceptibility of gene-ralized aggressive periodontitis (GAgP). METHODS: The study was a case-control trial. A total of 372 GAgP patients and 133 periodontally healthy controls were recruited. The CYBA rs4673 and CETP rs12720922 polymorphisms were detected by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Logistic regression models were used to analyze the correlation of CYBA rs4673 and CETP rs12720922 variants with the susceptibility of GAgP. The interaction between the two gene polymorphisms to the susceptibility of GAgP was analyzed by the likelihood ratio test. The interaction model adopted was the multiplication model. RESULTS: The mean age of GAgP group and control group was (27.5±5.2) years and (28.8±7.1) years respectively. There was significant difference in age between the two groups (P < 0.05). The gender distribution (male/female) was 152/220 and 53/80 respectively, and there was no significant difference between GAgP group and controls (P>0.05). For CYBA rs4673, the frequency of CT/TT genotype in the GAgP group was significantly higher than that in the controls [18.0% (66/366) vs. 10.6% (14/132), P < 0.05]. After adjusting age and gender, the individuals with CT/TT genotype had a higher risk of GAgP (OR=1.86, 95%CI: 1.01-3.45, P < 0.05), compared with CC genotype. There was no statistically significant difference in distributions of the CETP rs12720922 genotypes (GG, AA/AG) between GAgP patients and healthy controls (P>0.05). A significant interaction between CYBA rs4673 and CETP rs12720922 in the susceptibility to GAgP was observed. The GAgP risk of the individuals with CYBA rs4673 CT/TT and CETP rs12720922 GG genotypes was significantly increased (OR=3.25, 95%CI: 1.36-7.75, P < 0.01), compared with those carrying CC and AA/AG genotypes. CONCLUSION: CYBA rs4673 CT/TT genotype is associated with GAgP susceptibility. There is a significant interaction between CYBA rs4673 CT/TT genotype and CETP rs12720922 GG genotype in the susceptibility of GAgP.

[In vivo study of strontium-doped calcium phosphate cement for biological properties].

OBJECTIVE: To evaluate the biocompatibility and osteogenic effect of new calcium phosphate cement (CPC) in vivo and to provide experimental basis for its further clinical application. METHODS: Thirty New Zealand white rabbits were randomly divided into four groups: CPC group, CPC+Bio-Oss group, Bio-Oss group and blank control group. Bone defect models of 6 mm in diameter and 7 mm in depth were made on the lateral condyle of bilateral hind legs of the rabbits. CPC, Bio-Oss and CPC+Bio-Oss mixture were implanted into the bone defect according to the group, and the mass ratio of CPC and Bio-Oss was 4 ∶ 1. The experimental animals were sacrificed the 4th, 12th and 24th week after operation. The tissue around the bone defect was taken for histological evaluation by H&E staining. Bone ingrowth fraction (BIF) was calculated. The expression of BMP-2 and COL-Ⅰ was detected by immunohis- tochemical staining by calculating the mean optical density (MOD) of the positive area the 4th week after operation, and the bone healing of each group was evaluated at different time points. The measurement data were analyzed by one-way ANOVA and LSD test was used for multiple comparison of the differences between the means by SPSS 19.0. P < 0.05 was considered to be statistically significant. RESULTS: The results of H&E staining showed that the BIF values of CPC group, CPC + Bio-Oss group and Bio-Oss group were significantly higher than those of blank control group at the same time point (P < 0.01). The BIF values of CPC group were lower than those of Bio-Oss group and CPC + Bio-Oss group (P < 0.01). There was no significant difference between CPC + Bio-Oss group and Bio-Oss group. Immunohistochemical staining showed that the MOD values of BMP-2 and COL-Ⅰ in CPC group were higher than those in blank control group, but lower than those in Bio-Oss group and CPC+Bio-Oss group (P < 0.01). There was no significant difference between BMP-2 and COL-Ⅰ in CPC+Bio-Oss group and Bio-Oss group. CONCLUSION: The new calcium phosphate cement has good biocompatibility and can promote early osteogenesis with stable and long-term effect.

[Efficacy of two barrier membranes and deproteinized bovine bone mineral on bone regeneration in extraction sockets: A microcomputed tomographic study in dogs].

OBJECTIVE: To evaluate the effect of two barrier membranes [multilaminated small intestinal submucosa (mSIS) and bioresorable collagen membrane (Bio-Gide)] combined with deproteinized bovine bone mineral Bio-Oss on guided bone regeneration through a canine extraction sockets model. METHODS: The distal roots of 18 premolars of the Beagle' s bilateral maxillary and mandibular were removed, and 18 extraction sockets were obtained. They were randomly divided into 3 groups, and the following procedures were performed on the sockets: (1) filled with Bio-Oss and covered by mSIS (mSIS group), (2) filled with Bio-Oss and covered by Bio-Gide (BG group), (3) natural healing (blank control group). Micro-computed tomograph (Micro-CT) was performed 4 and 12 weeks after surgery to eva-luate the new bone regeneration in the sockets of each group. RESULTS: The postoperative healing was uneventful in all the animals, and no complications were observed through the whole study period. Micro-CT analysis showed that the new bone fraction in the mSIS group and the BG group was significantly higher than that in the blank control group at the end of 4 weeks and 12 weeks (P < 0.05), and more new bone fraction was observed in the mSIS group than in the BG group, but the difference was not statistically significant (P>0.05). The new bone fraction of coronal third part of the socket in the mSIS group and BG group at the end of 4 weeks were significantly higher than that of the middle and apical third part of each group (P < 0.05). The values of bone mineral density were similar at 4 weeks in all the groups (P>0.05), but were significantly higher than that in the control group at the end of 12 weeks (P < 0.05). The bone morphometric analysis showed that the trabecular number and trabecular spacing were significantly better in the mSIS group and the BG group than in the control group at the end of 4 weeks and 12 weeks (P < 0.05), while the value in the mSIS group was slightly higher than in the BG group, but the difference was not statistically significant (P>0.05). The difference in trabecular thickness between all the groups was not statistically significant (P>0.05). CONCLUSION: mSIS membrane as a barrier membrane combined with deproteinized bovine bone mineral can enhance new bone formation in canine extraction sockets, similar to Bio-Gide collagen membrane.

[Biocompatibility and effect on bone formation of a native acellular porcine pericardium: Results of in vitro and in vivo].

OBJECTIVE: To examine the morphology and biocompatibility of a native acellular porcine pericardium (APP) in vitro and to evaluate its barrier function and effects on osteogenesis when used in guided bone regeneration (GBR) in vivo. METHODS: First, the morphology of APP (BonanGenⓇ) was detected using a scanning electron microscope (SEM). Next, for biocompatibility test, proliferation of human bone marrow mesenchymal stem cells (hBMSCs) were determined using cell counting kit-8 (CCK-8) after being seeded 1, 3 and 7 days. Meanwhile, the cells stained with phalloidine and 4, 6-diamidino-2-phenylindole (DAPI) were observed using a confocal laser scanning microscopy (CLSM) to view the morphology of cell adhesion and pattern of cell proliferation on day 5. A 3-Beagle dog model with 18 teeth extraction sockets was used for the further research in vivo. These sites were randomly treated by 3 patterns below: filled with Bio-OssⓇand coverd by APP membrane (APP group), filled with Bio-OssⓇand covered by Bio-GideⓇmembrane (BG group) and natural healing (blank group). Micro-CT and hematoxylin-eosin (HE) were performed after 4 and 12 weeks. RESULTS: A bilayer and three-dimensional porous ultrastructure was identified for APP through SEM. In vitro, APP facilitated proliferation and adhesion of hBMSCs, especially after 7 days (P < 0.05). In vivo, for the analysis of the whole socket healing, no distinct difference of new bone ratio was found between all the three groups after 4 weeks (P>0.05), however significantly more new bone regeneration was detected in APP group and BG group in comparison to blank group after 12 weeks (P < 0.05). The radio of bone formation below the membrane was significantly higher in APP group and BG group than blank group after 4 and 12 weeks (P < 0.05), however, the difference between APP group and BG group was merely significant in 12 weeks (P < 0.05). Besides, less resorption of buccal crest after 4 weeks and 12 weeks was observed in APP group of a significant difference compared in blank group (P < 0.05). The resorption in BG group was slightly lower than blank group (P>0.05). CONCLUSION: APP showed considerable biocompatibility and three-dimentional structure. Performing well as a barrier membrane in the dog alveolar ridge preservation model, APP significantly promoted bone regeneration below it and reduced buccal crest resorption. On the basis of this study, APP is a potential osteoconductive and osteoinductive biomaterial.

[The application value of multi-material artifact reduction technique in maxillofacial CT images of patients with metallic dental implants].

Objective: To investigate the effect of multi-material artifact reduction (MMAR) technique on the maxillofacial CT images of patients with metallic dental implants. Methods: The data of 30 patients with metal denture implants who underwent maxillofacial wide-detector CT scans in the Department of Radiology of the First Affiliated Hospital of Zhengzhou University from March 2019 to February 2020 were retrospectively collected. The images of the lesion sites of patients were all affected by the metal implants artifacts. The 120 kV-like, virtual monoenergetic images (VMI) (70, 90, 110 keV), VMI (70, 90, 110 keV)+MMAR images were reconstructed at venous phase by energy spectrum scanning. A total of 7 image sequences were obtained for each patient. The CT value and noise value of the lesion and the longus capitis muscle on the same plane were measured, and the artifact index (AI) of lesion was calculated.Friedman test and Wilcoxon test were used to evaluate image quality objectively and subjectively. Results: There were significant differences in SD and AI among the 7 groups (χ2=133.800,P<0.001;χ2=92.147,P<0.001). The SD[10 (8, 12)] and AI [6 (5, 9)]of VMI 110 keV+M images were the lowest, but there were no significant differences in AI between VMI 110 keV+M and VMI 90 keV+M image (P= 0.271). The SD and AI of VMI+M group were lower than those in VMI group (all P<0.05). There was significant difference in image score among the 7 groups (χ 2 = 151.199, P<0.001). The image scores of VMI (70, 90, 110 keV)+M group were higher than those of VMI group (Z=-4.583, P = 0.000; Z=-3.742, P = 0.000; Z =-2.449, P = 0.014). The subjective score of VMI 90 keV+M [4 (3, 4)] was the highest, higher than those of other 6 groups (all P<0.05), in 26 out of 30 cases, lesions displayed clear contrast, and the artifacts eliminated completely. Conclusion: The MMAR technique of wide-detector CT might effectively remove the metallic dental implants artifacts and improve the image quality. VMI 90 keV+MMAR images could achieve the best artifact removal effect and good tissue contrast.

[Clinicopathological features and prognosis of the skeletal-muscle cytotoxic T-cell lymphoma].

Objective: To investigate the clinicopathological features and prognosis of skeletal-muscle cytotoxic T-cell lymphoma (CTL). Methods: The clinical data of 14 cases of skeletal muscle CTL and 47 cases of non-skeletal muscle extranodal CTL patients in Beijing Friendship Hospital Affiliated to Capital Medical University and the 989 Hospital of the joint logistics support force of the people's Liberation Army (the former 152 hospital) from 2008 to 2019 were collected retrospectively. Immunophenotype, EBV infection status and T-cell receptor (TCR) clonality of tumor cells were evaluated. The clinicopathological features and prognosis of the two groups were compared. Results: Skeletal-muscle CTL accounted for 23.0% (14/61) of extranodal CTL in the same period. The median age of the patients was 42.3 years (range 11-76 years), including six males and eight females. The main clinical manifestations were painless masses. Two patients (2/14) had B symptoms. The tumors occurred in the cheek (7 cases), the tongue (4 cases), the lower lip (3 cases) and the left upper arm (2 cases), and in two cases had two sites. Ten cases were of stage ⅠE and four cases stage ⅡE. Compared with non-skeletal-muscle extranodal CTL, many patients of skeletal-muscle CTL did not have B symptoms, the clinical stage was lower, and the tumor mainly involved the oral cavity (cheek, tongue and lip, P<0.05). Morphologically, the tumor showed diffuse infiltration of heterotypic lymphocytes in skeletal muscle. Immunohistochemistry showed that in 11/14 cases, there were reduced or loss of expression of some the T cell antigens (CD2, CD3, CD5, CD7). TIA-1, Gr B and CD8 (CD8+>CD4+) were expressed in all cases, and CD56 was negative. The median Ki-67 proliferation index was 35.0% (range 5%-60%). EBER in situ hybridization was negative in all cases. The results of TCR clonality analysis showed clonal TCR gene rearrangement were detected in eight cases. The median follow-up time was 40 months (range 10-67 months). Ten patients were tumor free; the 5-year survival rate of skeletal-muscle CTL was 100%. Compared with non-skeletal-muscle extranodal CTL (5-year overall survival rate was 35.9%), the difference was statistically significant (χ²=8.277, P=0.004). Conclusions: Skeletal-muscle CTL mostly occurs in the skeletal muscle of cheek and mouth. Tumor cells show morphologic characteristics of muscle invasion and myositis-like feature. It also shows CD8+>CD4+immunophenotype, cytotoxic molecular pattern and is associated with low clinical stage and good prognosis.

[Five-year clinical outcomes of the second generation biodegradable polymer sirolimus-eluting stent (EXCROSSAL) in treating patients with de novo coronary lesions].

Objective: To evaluate the five-year safety and efficacy of the second generation biodegradable polymer sirolimus-eluting stent (EXCROSSAL) in treating patients with de novo coronary artery diseases. Methods: Patients with coronary artery disease (CAD)who were implanted with EXTROSSAL stents in CREDIT Ⅱ and CREDIT Ⅲ study were included. CREDIT Ⅱ was a randomized trial, and CREDIT Ⅲ was a single-arm study. From November 2013 to December 2014, 833 CAD patients with de novo coronary lesions implanted with EXTROSSAL stents were selected from 33 centers in China. The primary outcome was 5-year target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction and clinically indicated target lesion revascularization. Secondary endpoints was patient-oriented composite endpoint (PoCE), including all-cause death, all myocardial infarction, or any revascularization within 5 years post stenting and stent thrombosis according to Academic Research Consortium's (ARC) definition. Kaplan Meier method was used to calculate the incidence of TLF and PoCE within 5 years after operation. Univariate Cox regression analysis was used to analyze the impacts of diabetes, small vessel disease (vessel diameter ≤ 2.74 mm), lesion length ≥ 16.7 mm and multivessel disease on the incidence of TLF within 5 years after operation. Results: A total of 833 patients were included in this study including 579 males (69.5%), the age was (59.3±9.1) years. And 832 (99.9%) patients completed 5-year clinical follow-up. The incidence of TLF and PoCE in the 5-year follow-up were 10.6%(86/811) and 15.5%(126/811), respectively. Stent thrombosis occurred in 1.0%(8/811) of patients. Univariate Cox regression analysis showed that vessel diameter ≤ 2.74 mm (HR=3.20,95%CI 1.90-5.39,P<0.001), lesion length ≥ 16.7 mm (HR=1.88,95%CI 1.18-2.99,P=0.007) and multivessel disease (HR=2.44,95%CI 1.60-3.72,P<0.001) were related factors of TLF within 5 years after operation. Conclusion: EXCROSSAL stent is effective and safe in treating CAD patients with de novo coronary lesions, with low incidence of TLF and PoCE within 5 years after operation.

CCL18 overexpression predicts a worse prognosis in oral squamous cell carcinoma (OSCC).

Oral squamous cell carcinoma (OSCC) presents severe morbidity and high mortality owing to local recurrence or remote metastasis. Molecular markers, including chemokines, might provide more efficient prognostic information or even therapeutic targets for the treatment of OSCC. Using quantitative RT-qPCR, we found that CCL18 was dramatically overexpressed in 30 OSCC tissues at the mRNA level in comparison with their adjacent non-cancerous oral mucosa tissues and 15 oral mucosa tissues from non-malignant patients. We then analyzed the relationship between CCL18 overexpression and patient clinical characters and outcomes using immunohistochemistry staining (IHC) in 102 paired OSCC cancerous and adjacent non-cancerous tissues; the increase in CCL18 expression was significantly higher in male patients (p=0.047), tumors of the palate and floor of the mouth (p=0.014), patients with positive lymph node metastasis (p=0.007), and patients with poor tumor differentiation (p=0.029). The median overall survival time and time-to-recurrence were 80.6 and 61.4 months in patients with high CCL18 expression, respectively, as against 93.4 and 81.6 months in patients with comparatively lower CCL18 expression, respectively (p=0.033 and 0.012, respectively; log-rank test). Multivariate analyses indicated age, poor differentiation, and CCL18 levels to be independent prognostic factors for predicting both overall and disease-free survival time. Our study suggests that CCL18 is a novel candidate marker for the OSCC malignancy and prognosis, including lymph node metastasis, time-to-recurrence, and disease-free survival time.

[Evaluation of wear property of Giomer and universal composite in vivo].

OBJECTIVE: To observe the wear performance of Giomer and universal composite for posterior restorations by 3D laser scan method, in order to guide the material selection in clinic. METHODS: In this study, 48 patients (108 teeth) were selected according to the inclusion and exclusion criteria. All the patients in need of a minimum of 2 Class Ⅰ and/or Class Ⅱ restorations were invited to join the study. The teeth were restored with Giomer (Beautifil Ⅱ, BF) and universal composite (Filtek Z350, Z350) randomly. The restorations were evaluated at baseline and after 6-, 18-, 48-month using the modified United States Public Health Service (USPHS) criteria for clinical performance. The in vivo images and gypsum replicas were taken at each recall. A 3D-laser scanner and Geomagic Studio 12 were used to analyze the wear depth quantitatively. Statistical analysis was performed with SPSS 20.0. RESULTS: After 4 years, 89.6% patients were recalled. The survival rate of both materials was 95.8% (Kaplan-Meier survival analysis). Seven restorations of the two materials failed due to loss of restoration, bulk fracture, secondary caries and pulp necrosis. The wear patterns of restorations were divided into 2 classes. Pattern Ⅰ: occlusal contact areas showed the deepest and fastest wear depth; pattern Ⅱ: the wear depth was slow and uniform. Both materials showed a rapid wear in the first 6 months. Then the wear rate was decreased. The occlusal wear depth after 4 years were (58±22) µm and (54±16) µm for BF group and Z350 group respectively, which were in accordance with the American Dental Association (ADA) guidelines (wear depth for 3 years < 100 µm). No significant differences (P>0.05) were observed between the two groups. Regarding the restorations with wear pattern Ⅰ, the wear depth of BF group was higher than Z350 group at 6- and 48-month (P < 0.05), while there was no significant difference between restorations with wear pattern Ⅱ (P>0.05). CONCLUSION: Within the limitation of the study, after 4 years, the survival rate and wear resistance of Giomer met ADA guidelines for tooth-colored restorative materials for posterior teeth. When the two materials were applied in occlusal contact areas, wear resistance of Giomer was slightly lower than universal composite resin. No significant difference was found when they were applied in none of the occlusal contact areas.

[Effect of concentrated growth factors combined with guided tissue regeneration in treatment of classII furcation involvements of mandibular molars].

OBJECTIVE: Tissues loss due to periodontal disease is typically treated by a variety of regenerative treatment modalities, including bone grafts, guided tissue regeneration (GTR) and growth factors, to reform the supporting tissues of teeth. Concentrated growth factors (CGF) are produced by centrifuging blood samples at alternating and controlled speeds using a special centrifuge. The purpose of this study was to evaluate whether GTR could improve the effect of CGF combined with bone graft in the treatment of classII furcations of mandibular molars. METHODS: In the present study, thirty-five classII furcation involvements were included and randomly divided into two groups. The experimental group (n=17) accepted GTR combined with CGF and bone graft therapy, and the controlled group (n=18) accepted CGF combined with bone graft therapy. The clinical examinations and cone beam computed tomography (CBCT) were performed at baseline and 1 year post-surgery. Comparisons of clinical and CBCT data before and after operation between the experimental group and the control group were made. RESULTS: The clinical and CBCT data of both groups were not statistically different at baseline (P>0.05). At the end of 1 year post-surgery, the clinical parameters of both groups were significantly improved (P<0.001). The probing depths of the experimental group were (4.81±1.95) mm and (3.56±1.94) mm, respectively, significantly higher than the changes of the control group (P<0.001). The vertical and horizontal attachment gains of the experimental group were (4.11±1.98) mm and (3.84±1.68) mm, respectively, significantly higher than the changes of the control group (P<0.001). At the end of 1 year post-surgery, the experimental group showed significantly higher bone gain at vertical and horizontal directions compared with those of the control group: (3.84±1.68) and (3.88±2.12) mm, respectively (P<0.001). CONCLUSION: Within the limitation of the present study, GTR showed positive role in the effect of CGF combined with bone graft in the treatment of classII furcation involvements of mandibular molars.