Consensus of experts on the medical risk prevention for the patients with cardiovascular diseases during dental treatment (2022 edition) / 中华口腔医学杂志

With the aging process of population in the society, the prevalence of cardiovascular diseases (CVD) in China is increasing continuously and the number of dental patients with CVD is increasing gradually too. Due to the lack of guidelines for dental patients with CVD in our country, how to implement standardized preoperative evaluation and perioperative risk prevention remains a problem to be solved for dentists at present. The present expert consensus was reached by combining the clinical experiences of the expert group of the Fifth General Dentistry Special Committee, Chinese Stomatological Association and respiratory and cardiology experts in diagnosis and treatment for CVD patients, and by systematically summarizing the relevant international guidelines and literature regarding the relationship between CVD and oral diseases and the diagnosis and treatment of dental patients with heart failure, hypertension and antithrombotic therapy. The consensus aims to provide, for the dental clinicians, the criteria on diagnosis and treatment of CVD in dental patients in China so as to reduce the risk and complications, and finally to improve the treatment levels of dental patients with CVD in China.

Consensus of experts on the oral health management and medical risk prevention for the patients with chronic airway diseases (2022 edition) / 中华口腔医学杂志

Today, there is greater awareness on the association between oral diseases and respiration diseases after the outbreak of COVID-19. However, confusion regarding the oral health management and medical risk prevention for patients with chronic airway diseases has been remained among dental clinicians. Therefore, the dental experts of the Fifth General Dentistry Special Committee, Chinese Stomatological Association, combined with the experts of respiratory and critical care medicine, undertook the formation of consensus on the oral health management of patients with chronic airway diseases in order to help dental clinicians to evaluate medical risks and make better treatment decision in clinical practice. In the present consensus report, the relationship of oral diseases and chronic airway diseases, the oral health management and the treatment recommendations of patients with chronic airway diseases are provided.

Study of bond strength of one-piece glass fiber posts-and-cores with flared root canals in vitro / 北京大学学报(医学版)

OBJECTIVE@#To compare the effects of three kinds of fiber posts (CAD/CAM one-piece glass fiber posts-and-cores, prefabricated glass fiber post and light curing plastic fiber post) on the bond strength of flared root canals and the effect of thermal cycling on their bond strength.@*METHODS@#Extracted human single teeth (n=90) were endodontically treated and randomly divided into three groups (n = 30 each). The teeth were restored by three kinds of fiber post: CAD/CAM one-piece glass fiber posts-and-cores, prefabricated posts and light curing plastic fiber post. Following post cementation, the specimens were stored in distilled water at 37 °C for 7 days. Half bonded specimens of each group were submitted to thermal cycling (6 000 times, 5 to 55 °C) prior to micro-push-out bond strength test. Fabrication of micro-push-out bond strength test specimens was conducted by precision slicing machine. The micro-push-out bond strength was tested using a universal testing machine, and the failure modes were examined with a stereomicroscope.@*RESULTS@#In CAD/CAM one-piece glass fiber posts-and-cores group, the bond strength of cervical, middle and apical was (9.58±2.67) MPa,(8.62±2.62) MPa,(8.21±2.48) MPa respectively before thermal cycling, and after thermal cycling the bond strength of cervical, middle and apical was (8.14±3.19) MPa,(6.43±2.47) MPa,(6.45±3.20) MPa respectively. In prefabricated posts group, the bonding strength of cervical, middle and apical was (3.89±2.04) MPa,(4.83±1.23) MPa,(4.67±1.86) MPa respectively before thermal cycling, and after thermal cycling the bond strength of cervical, middle and apical was (6.18±1.61) MPa,(5.15±1.94) MPa,(6.39±2.87) MPa respectively. In light curing plastic fiber post group, the bond strength of cervical, middle and apical before thermal cycling was (4.05±2.41) MPa,(1.75±1.70) MPa,(2.60±2.34) MPa respectively, and after thermal cycling the bond strength of cervical, middle and apical was (5.04±2.72) MPa,(1.96±1.70) MPa,(1.34±0.92) MPa respectively. Postal types and root canal regions were found to significantly affect the push-out bond strength. Compared with the other two groups, the one-piece glass fiber posts-and-cores had the highest bonding strength in the cervical, middle and apical. Temperature cycling has no significant effect on the micro push-out bond strength of three kinds of fiber posts.@*CONCLUSION@#One-piece glass fiber posts-and-cores has better bonding strength and excellent bonding performance.

Salivary microbiome in people with obesity: a pilot study / 北京大学学报(医学版)

OBJECTIVE@#To investigate the characterization of the salivary microbiome in people with obesity and the differences in microbial composition, gene function and metabolic pathways of salivary microbiome between people with obesity and normal weight controls.@*METHODS@#The study was carried out in people with obesity and age- and sex-matched normal weight controls. None of these selected participants had the systemic disease, oral mucosal disease or periodontal disease. Unstimulated saliva samples were collected and oral examination was conducted. DNAs from saliva samples were extracted and sequenced in an Illumina NextSeq 500 platform. Community composition, linear discriminant analysis of taxonomic differences,gene prediction, gene set construction and annotation of gene function were performed.@*RESULTS@#The classified bacterial reads of the samples were 2 630 428 for each sample. A total of 11 phyla, 19 classes, 26 orders, 41 families, 62 genera and 164 species were detected ultimately. All samples had the same predominant phyla (Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria and Fusobacteria). There were statistical differences between the groups at the class, order, family, genus and species levels. At the class level, Negativicutes and Erysipelotrichia were more abundant in the obesity group, while Flavobacteriia and Bateroidetes dominated in normal weight group (P<0.05). At the species level, 16 showed significant differences in relative abundance among the groups, in which Prevotella melaninogenica,Prevotella salivae,Solobacterium moorei and Atopobium parvulum ware more abundant in the obesity group, whereas Streptococcus sanguinis dominated in normal weight group (P<0.05). The people with obesity had a higher number of salivary microbial genes (P<0.05). We produced statistics on gene prediction and found salivary microbiome of obesity group had a higher number of genes (P < 0.05). Genes associated with the pathways of metabolism and environmental information processing and human diseases were significantly enriched in the saliva samples of people with obesity (P < 0.01).@*CONCLUSION@#Significant differences were seen in composition, gene function and metabolic pathways of salivary microbiome between people with obesity and normal weight people. We hope to go on further study with larger sample size in the near future.

Effects of isoquercitrin from Craibiodendron yunnanense on osteogenic differentiation of MC3T3-E1 cells / 中国中药杂志

Natural products especially flavonoids are being explored for their therapeutic potentials in reducing bone loss and maintaining bone health. The present study is to investigate the effects of isoquercitrin from Craibiodendron yunnanense with different concentrations at 1 x 10(-4), 1 x 10(-5), 1 x 10(-6), 1 x 10(-7) mol x L(-1) on proliferation, differentiation and mineralization of MC3T3-E1. Cell proliferation was assessed by CCK-8 kit at 1, 3, 5 and 7 days of culture. Alkaline phosphatase (ALP) activity were performed qualitatively and quantitatively on day 7, and alizarin red S staining was employed to access the mineralization of cells on day 21. The osteogenic markers ALP, collagen type I (COL 1A1), runt-related transcription factor 2 (Runx-2) and Osterix were detected to analysis early osteogenic differentiation of cells on day 3 by RT-PCR. The results showed that isoquercitrin had a dose-dependent effect on the proliferation, osteogenic differentiation, mineralization and gene expression of MC3T3-E1 in the range from 1 x 10(-7) to 1 x 10(-5) mol x L(-1). At concentrations above 1 x 10(-4) mol x L(-1) isoquercitrin showed cytotoxicity, while 1 x 10(-6) mol x L(-1) is the optimal concentration of isoquercitrin to improve the osteoblastic activity. All these results implied that isoquercitrin might be the major composition of traditional Chinese medicine C. yunnanense to treat bone fractures.

Effect of surface treating methods on the shear strength of luting cements to Cercon zirconia / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the effect of surface treating methods on the shear strength of Panavia F luting cements to Cercon zirconia.</p><p><b>METHODS</b>Forty sample disc of Cercon zirconia with 20 mm in diameter and 4 mm in height were prepared. Another 40 sample discs with 5 mm in diameter and 4 mm in height were also prepared Both of the two types of samples were randomly devided into four groups A, B, C, and D in which different surface treatments were delivered. In group A samples was treated with 600# sand paper, and in group Bwith sand blasting, and silanization in group C, and sand blasting plus silanization in group D. All samples were bonded with Panavia F luting cement under the aid of glass mould. The value of shear strength was measured and statistically analysed.</p><p><b>RESULTS</b>The shear strength of four groups of samples were (21.50 ± 1.98), (23.68 ± 2.31), (20.69 ± 1.55), (24.01 ± 2.19) MPa respectively. The population mean was not equal. There was no significant difference between 600# sand paper treated group and silanization group, nor between sand blasting group and sand blasting plus silanization group.</p><p><b>CONCLUSIONS</b>Sand blasting is a effective means to increase the shear strength, and 600# sand paper treatment and silanization can't increase the shear strength.</p>

Influence of background color on chromatic value of four all-ceramic system core materials / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the influence of post-core background color on chromatic value of four all-ceramic system core materials at clinically appropriate thicknesses.</p><p><b>METHODS</b>Disc specimens of 15 mm in diameter and 0.80 mm in thickness (Empress II: Group A), and 0.50 mm in thickness (In-Ceram Zirconia core: Group B; Cercon base color zirconia core: Group C; Cercon base zirconia core: Group D) were fabricated, five in each group. Au-Pt alloy, Ni-Cr alloy and visible light cured dental composite resin (A2 color) background were prepared. Samples were put on different background and their chromatic values were measured with colorimeter (CIE-1976-L(*)a(*)b(*)). Color differences of each specimen on different background material were calculated.</p><p><b>RESULTS</b>The color differences among specimens of Group A on different background material were more than 1.5 (2.83 ± 0.70) which meant it could be noticeable to eyes. Those of zirconia were less than 1.5 [Group B: (0.14 ± 0.08); Group C: (0.90 ± 0.20); Group D: (0.99 ± 0.09)].</p><p><b>CONCLUSIONS</b>The influence of background color on Group A was noticeable to human eyes, and as a result, tooth-colored post should be used for this all-ceramic system. For the other three kinds of zirconia core materia1 system, the color differences among specimens on different background material were unnoticeable. Therefore the three all-ceramic systems have excellent color masking ability and can be used on all color background.</p>