Objective To investigate the time-effect relationship of hyperbaric oxygen(HBO) exposure on platelet rich fibrin(PRF) to secreting platelet endothelial cell adhesion molecule-1(PECAM-1) and vascular endothelial growth factor(VEGF). Methods A total of 28 volunteers were randomly divided into 4 groups (n=7):HBO 1 group(exposed to 0.25 MPa HBO for 10 min), HBO 2 group (exposed to 0.25 MPa HBO for 30 min),HBO 3 group(exposed to 0.25 MPa HBO for 60 min) and the control group (air exposure for 60 min). PRF in each group was fixed with 4% paraformaldehyde respectively. PECAM-1 and VEGF positive staining were qualitatively and quantitatively determined by immunohistochemical staining and micro-spectrophotometer. The ultra-structural changes of PRF were observed by transmission electron microscope(TEM). Results In control group, PECAM-1 and VEGF staining were positive in PRF. The positive degrees of PECAM-1 and VEGF staining in PRF in HBO 1 group,HBO 2 group and HBO 3 group were higher than that in control group. The positive staining was mainly located in the upper part of white blood cell, and spread to the fiber end after the exposure of HBO. Quantitative determination showed that the contents of PECAM-1 and VEGF in the HBO exposed group were significantly different from those in the control group. The secretory contents of PECAM-1 and VEGF in HBO 2 group and HBO 3 groups were significantly higher than those in HBO 1 group. The platelet granule release in HBO 1 group, HBO 2 group and HBO 3 group was significantly higher than that in control group. The secreted platelet granules were located in the cells or collagenous fibers. Little apoptosis of leukocytes was observed in HBO 3 group. Conclusion HBO exposure to PRF significantly promotes the secretion of PECAM-1 and VEGF.

Objective To investigate the mechanism of Porphyromonas gingivalis (P. gingivalis) transcription factor SinR and tyrosine kinase Ptk1 on the production of exopolysaccharide and the regulative relation between upstream and downstream. Methods The PCR fusion technique was employed to generate allelic exchange mutants of sinR (ΔsinR) and ptk1/sinR double deletion mutant (Δptk1/sinR) in ATCC 33277 . The exopolysaccharide production of Δptk1、ΔsinR and Δptk1/sinR strain of P. gingivalis with fluorescent lectins was detected by laser scanning confocal microscope (CLSM). Results Polysaccharide production of Δptk1 and Δptk1/sinR significantly decreased（P＜0.05）, while that of ΔsinR significantly increased, compared with wild strain P. gingivalis 33277（P＜0.05）. Conclusion These data suggest that SinR and Ptk1 have significant regulatory effects on of exopolysaccharide synthesis in P.gingivalis. In addition, Ptk1 functioned downstream of SinR for exopolysaccharide production in P. gingivalis.

Objective To preliminarily study the expression of MMP-2 in the process of the movement of the orthodontic root of rats under the function of Gushukang, to explore its role in the development of root absorption, and to provide theoretical reference basis for the prevention and treatment of orthodontic clinical root absorption. Methods 60 male SD rats were randomly divided into experimental group (30) and control group (30).The experimental group used Gushukang to fill the stomach, while the control group used distilled water to fill the stomach, the given dose was 2.1 g/kg body weight, lavaged once every morning. Experimental group and control group were respectively divided into strength 0 d, 3 d, 7 d and 14 d and 21 d and 28 d groups, each group with five. Two groups of animals were given to 0.6 N force to pull the right maxillary first molar mesial movement.Orthodontic tooth mobility of rats root absorption model was set up. The experimental rats were put to death according to the time schedule respectively. HE staining was used to observe morphological changes of root absorption, and immunohistochemistry was used to observe the expression of MMP-2 in the root absorption area. Results By the comparison of two groups of rats with different tooth movement time and root absorption index, it was found that with the extension of time, the root absorption indexes increased gradually, and the root absorption began to appear on the third day, then gradually increased. After 14 d root absorption rate slowed down, through the same time comparison between groups, root absorption degree of Gushukang group was lighter than the control group.Except for the fact that root absorption indexes of 0 d, 3 d groups had no statistical significance (P＞0.05), the rest groups were statistically significant (P<0.05). Immunohistochemical results showed that the expression of MMP-2 in the strength 0 group was weaker, with the extension of time, the number of MMP-2 positive cells increased. The two groupshad a strong positive expression on 7 d in peak, after 14 d began to gradually decline. The expression of MMP-2 of Gushukang group on 21 d was weak. In the control group, MMP-2 expressed weakly on 28 d and tended to the level of normal tissue. Conclusion MMP-2 is one of the main inflammatory mediums absorbed by the root and is involved in the process of root absorption. The Gushukang is effective in inhibiting the absorption of orthodontic movement roots.

Objective To investigate the effects of rhLF on the proliferation and apoptosis in oral cancer KB cell line in order to achieve a new effective treatment for oral cancer patients. Methods KB cells were treated with different doses of rhLF (0,12.5,25,50,100,200 μg/mL) for 24,48,72 h and cell viability was detected by CCK-8 assay. Immunofluorescence was used to evaluate the expression of DNA damage associated protein γ-H2AX. Western blotting was performed to examine the expressions of γ-H2AX. Colony formation of the cells was observed after KB cells had been treated with rhLF at 0,200 μg/mL for 14 days. JC-1 assay was used to measure the changes in mitochondrial membrane potential, Annexin V-PI staining was used to observe the cell apoptosis. Western blotting was employed to detect the expressions of Parp and Caspase-3. Results rhLF caused significant suppression of KB cells proliferation. Immunofluorescence showed the increase of γ-H2AX after cells were incubated with rhLF. Western blotting displayed that the expressions of γ-H2AX gradually increased in dose-dependent. Meanwhile, rhLF significantly inhibited KB cells colony formation. Exposure to rhLF (0, 50, 200 μg/mL) after 48 h resulted in 2.02%, 7.60% and 48.07% cell apoptotic rates. Exposure of the cells to increased concentrations of rhLF gradually increased the apoptotic rate and decreased mitochondrial membrane potential. rhLF increased the expression of activated Parp, Caspase-3. Conclusion rhLF can inhibit the proliferation and induce apoptosis of KB cells, the rhLF of which may be associated with the activation of the mitochondrial apoptotic pathway.

Objective To study the relationship between Treponema denticola(Td) and sulfide levels (SUL) in periodontal pocket of the patients with chronic periodontitis. Methods Seventeen patients with chronic periodontitis were included, sulfide levels of periodontal pocket, probing depth, clinical attachment loss, and bleeding on probing were measured by Diamond Probe /Perio 2000 system. Meanwhile, Treponema denticola was detected by 16S rRNA PCR. Results The detection rate of Treponema denticola was 88.2% in the patients with chronic periodontitis. The detection rates of Treponema denticola in sulfide-negative and sulfide-positive sites were 68.5% and 43.2%, respectively, which was statistically significant between the two groups (P<0.01). The mean values of clinical attachment loss in sulfide-positive and sulfide-negative sites were (2.84±2.33) mm and (1.83±1.60) mm, respectively, which was statistically significant between the two groups(P<0.01). The mean values of probing depth in sulfide-positive and sulfide-negative sites were (4.20±1.57) mm and (3.83±1.30) mm, respectively, which showed no statistical significance (P＞0.05). The detection rate of BOP(+) in sulfide-positive sites was 92.5%, greater than that of 75.8% in sulfide-negative sites, which showed significant difference between the two groups (P<0.01). Conclusion Sulfide levels in periodontal pocket of the patients with chronic periodontitis may reflect the distribution of periodontal Treponema denticola.

Objective To measure the thickness of palatal mucosa in a Chinese population, analyze the change rules and relevant factors, and observe the thickness,histologic characteristics, and distribution rules in different layers. Methods Measurements of the palatal mucosa were obtained in 45 measure points, from 36 adults who were divided into three groups according to gingiva biotypes by bone sounding method. And residual soft tissues were collected from the palatal graft of periodontal augmentation procedures and stained using Harris hematoxylin. The platal mucosa with entire layers were selected as samples, and immunohistochemistry technology was applied to observe the histologic characteristics and distribution rules of connective tissues under the microscope.Biopsies with all layers of palatal mucosa were chosen for further histologic analysis. Results The overall mean thickness of palatal masticatory mucosa was(3.52±1.02)mm,(3.26±0.81)mm in canine region,(3.57±1.05)mm in the first premolar region,(3.72±1.04)mm in the second premolar region, (3.33±0.96)mm in the first molar region,(3.73±1.11)mm in the second molar region. No difference was observed between genders and ages. An association was observed between the thickness and biotypes. HE staining showed that the layer of connective tissues of palatal mucosa had dense collagenous fiber, the thickness of lamina propria increased from canine region to the first premolar region and then decreased toward the posterior palatal area. The submucosa layers were obvious in the second premolar region, loose connective tissues were seen in the first molar region, while the posterior palatal area contained abundant adipose tissue, vessels and glands. Conclusions In the Chines population, the thickness of palatal mucosa decreases from the canine to the posterior palatal area and increases in the second molar area. And the thickness of palatal mucosa increases from gingival margin to the midpalatal suture in the canine, the first premolar and the second molar areas. The lamina propria of palatal mucosa contains dense connective tissues while the submucosa layer, which tends to occur from the second premolar area, contains abundant adipose tissue,vessels and glands.

Objective To evaluate the plaque control effect of desensitizing toothpaste with low friction and normal toothpaste. Methods A randomized, controlled, double-blind clinical trial was used. A total of 50 volunteers were recruited into the study. Everyone chose one side of mouth to use NO.1 toothpaste, and the other side used NO.2 toothpaste, then the toothpastes were unblinded, the NO.1 toothpaste was low friction desensitizing toothpaste containing 8% of arginine. The PLI of both sides was recorded respectively before brushing, after 15 seconds’ brushing, 30 seconds’ brushing, 60 seconds’ brushing and 120 seconds’ brushing. The effect of desensitizing toothpaste with low friction in plaque control was evaluated after statistical analysis. Results The plaque removal efficiency of normal toothpaste was higher than desensitizing toothpaste with low friction in 60 seconds, but there was no statistical difference between the two kinds of toothpaste after 120 seconds. Conclusion Desensitizing toothpaste with low friction can achieve the same effect of plaque removal as normal toothpaste after 120 seconds’ brushing.

Objective To estimate the effect of nitrous oxide anesthesia on patient pain perception during local anesthesia administration in children. Methods A simple randomized, double-blinded, placebo-controlled study was designed and implemented. 60 patients (aged 6 to 10) with anterior maxillary region impacted supernumerary teeth extraction surgery were randomly allocated to 2 groups: nitrous oxide-oxygen sedation (group A, n=30) and oxygen (group B, n=30). Frankl behavioral rating scale was adopted to evaluate the cooperation of each patient, depth of sedation using Modifed Observer's Assessment of Alertness/Sedation (OAA/S) scale. Pain perception for local anesthesia was assessed using face, legs, activity, cry and consolability (FLACC) behavioral pain assessment scale. Physiological parameters like respiratory rate (RR), heart rate (HR), and oxygen saturation (SPO2) were recorded. Results The Frankl behavioral rating scales in group A were better than those in group B (P<0.05). The FLACC scale in A group was lower than in B group (P<0.05). The patients were significantly more sedated in the group A compared to group B (P<0.05). The HR, SPO2 and RR in two groups had no significant difference (P＞0.05). Conclusion Nitrous oxide and oxygen enable a better management of acute pain related to local anesthesia procedures.

Objective To in vivo evaluate the accuracy of 3Shape TRIOS for the whole maxilla. Methods 28 healthy volunteers were recruited in the study. Everyone’s whole maxilla got intraoral scan for three times by 3Shape TRIOS and then received one conventional silicon impression. The conventional impression was poured into a gypsum castand three-dimensional(3D) digitized image was captured from the cast by an extraoral scanner, as the reference model. All datasets were imported to Geomagic software for 3D analysis. Color-coded deviation maps showed qualitative visualization of the deviations. Results For the digital impressions of palatal soft tissues, the accuracy was (131.70±35.50)μm and precision was (54.51±10.87)μm. For the digital impressions for upper full dentitions,accuracy was (77.95±13.86)μm and precision was (58.88±11.51)μm. There was no significant effect of palatal vault height on accuracy of digital impressions of palatal soft tissues (P>0.05), but arch width was found to have a significant effect on precision of intraoral digital impressions for full dentitions (P=0.02). Conclusions It is feasible to use the intraoral scanner to obtain digital impressions for whole upper jaws. Further studies should be carried out to confirm whether the accuracy of digital impressions for whole upper jaws is acceptable in clinic.

Objective To investigate the anxiety and depression of the patients with burning mouth syndrome (BMS), and explore the relationships among anxiety-depression and immunity. Methods 31 female patients with BMS were investigated by Manifest Anxiety Scale (MAS), Hamilton Depression Scale (HAMD),humoral immunity and lymphocyte subpopulation tests. The correlation among anxiety-depression and immunity was analyzed. The data were analyzed by SPSS19.0. Results The level of IgE in the anxiety group was lower than the non-anxiety group.The level of Helper T cells (CD4+) and ratio of CD4+/CD8+were lower than the control group. The level of the total lymphocyte in the depression group was lower than the control group, while the level of the natural killer cells was higher. These differences were significant (P<0.05). Conclusion The levels of cellular immunity and humoral immunity in anxiety group have differences with those in non-anxiety group.The level of cellular immunity in depression group has differences with that in non-depression group.

Objective To evaluate the effectiveness of sodium hypochlorite in heightening the shear bond strength of enamel by Meta-analysis. Methods The Cochrane Library, PubMed, CBM, CNKI, WanFang Data, VIP databases from inception to September 30th, 2017, were searched to collect relative studies on the influence of deproteinization of sodium hypochlorite on shear bond strength of enamel. Two reviewers independently screened the search results,extracted data and assessed the risk of bias of included studies. Then Meta-analysis was performed using RevMan5.3 software，while Stata 12.0 was used to valuate publication bias. Results A total of 10 studies were included, involving 179 teeth in treated and control groups respectively. The result of Meta-analysis showed that the pooled-MD and 95%CI for continuous variations were 3.86 and 3.06-4.66 respectively. Conclusion Treatment of tooth surface with sodium hypochlorite can significantly improve the shear strength of enamel.

Objective To investigate the efficacy and safety of Dentium oral repair membrane guided bone regeneration in dental implants. Methods A total of 148 dental implants in our hospital from October 2015 to October 2017 were selected and divided into 2 groups according to the random number table (74 cases). In the control group, bone regeneration was guided with titanium membrane, and in the observation group, the regeneration of bone was guided with the oral cavity repair membrane. The bone growth and complication rates were compared between the two groups. Results The bone growth in the observation group was better than that in the control group and there was statistical difference(P<0.05). The incidence of complications in the observation group was lower than that in the control group and the difference was statistically significant (P<0.05). Conclusion Dentium oral repair membrane guide bone regeneration applied to dental implants patients can effectively improve the bone growth effect and reduce the incidence of complications, whose application is worth promoting.

Objective To compare the correlation between halitosis and metabolic index in health examination subjects. Methods 2 885 health examination people were selected. Body weight, height, blood pressure, blood glucose, cholesterol, triglyceride, low density lipoprotein, high-density lipoprotein and uric acid were included in the analysis. Examination of the patient's halitosis, comparison of metabolic markers in patients with and without halitosis, in addition, the performance of halitosis group were analyzed. Results Men had a higher proportion of bad breath(P<0.01). The metabolic indexes, including body mass index, systolic blood pressure, diastolic blood pressure, fasting blood glucose, total cholesterol, triglyceride, low density lipoprotein and uric acid, were higher than those in the control group. The high density lipoprotein in the halitosis group was lower than that in the halitosis group. Bad breath of patients with halitosis was obviously stronger. Their mean levels of metabolism were lower than those in the halitosis group, which were higher in the breath group than in the halitosis group, except for that HDL average decreased. Conclusion There is a homogeneous relationship between halitosis and metabolic abnormalities. There is a correlation between the two.

Objective To investigate the caries prevalence rate in 7-to 9-year-old children in Gusu District of Suzhou. Methods 1 452 children aged 7~9 years old were randomly selected using cluster sampling method in Gusu District of Suzhou city and the caries prevalence was investigated. Eruption and the pit and fissure sealants of the first permanent molars were also examined. Results The caries prevalence rate of deciduous teeth was 77.69%. Mean dmft was 3.706. And the filling percentage was 14.48%. The rate of caries and filling of the deciduous teeth decreased with age. The caries prevalence rate of the first permanent teeth was 21.21%. Mean DMFT was 0.444. And the filling percentage was 9.15%.The rate of caries and mean DMFT were the lowest in the 8-year-old group. However, the filling percentage of the permanent teeth increased with age. The rate of pit and fissure sealants was 10.74%. Conclusion The caries prevalence rate of deciduous and permanent teeth in 7-to 9-year-old children in Suzhou is relatively high, while the filling percentage and sealants rate are at a low level. It is recommended to increase the proportion of pit and fissure sealants and strengthen the examination of oral health and follow-up.

Most tissue engineering approaches attempt to improve the regenerative effect after injury by combining stem cells with biocompatible materials and bioactive factors. The main components of bone tissue engineering are seeding cells, scaffolds and growth factors. The scaffold material is implanted into the bone tissue injury site, which can enhance the osteogenic ability of cells, improve the ability of bone tissue growth, thus promoting bone tissue regeneration. However, the implanted material may cause the host’s immune response, affect the results of bone tissue regeneration. This review summarizes the effects of scaffold-induced tissue immune response on bone tissue regeneration.

Type 2 diabetes mellitus is one of the major risk factors of chronic periodontitis, while chronic periodontitis increases the risk of type 2 diabetes mellitus. However, the pathogenesis of type 2 diabetes mellitus and chronic periodontitis has not been clarified so far. Non-surgical periodontal treatment can not only improve the condition of the periodontal tissues, but also ameliorate the blood glucose status of patients in some degree. With the development of molecular biology technology, studies on type 2 diabetes mellitus and chronic periodontitis from the perspectives of microorganisms, immunity, and inflammatory factors have been constantly deepened. In this paper, a review about the microbial indicators, immunity, inflammation indicators, clinical indicators of type 2 diabetes mellitus and chronic periodontitis was made. The effect of non-surgical periodontal treatment on illness was also reviewed carefully.

Endodontic root canal glide path preparation is defined as a preliminary patency of the root canal from the canal orifice to the apical foramen, which provides a smooth tunnel for subsequent shaping files to follow, and it is considered as the foundation for a safer root canal preparation. Mechanical glide path instruments were firstly introduced to the market in 2009, and it is gradually popularized in clinic. In this paper, the categories, the mechanical properties of several glide path systems and their preparation outcomes are extensively reviewed.

A perfect confident smile can greatly enhance one’s attractiveness. Smile aesthetics has become the primary reason why patients seek orthodontic treatment and the therapeutic goal of orthodontists. Understanding facial aesthetics and current societal preferences for facial attractiveness is mandatory for the orthodontists. Orthodontics understand the indicators of smile aesthetics, which can be used to guide clinical operation, thus achieving the best therapeutic effect. This paper summarizes the factors that influence smile aesthetics, such as the smile line, the arc of the smile, the buccal corridor, the teeth, the gingiva, etc., from the micro-aesthetics and the mini aesthetics of the smile.

The clinical advantages of platelet-rich fibrin (PRF) in combination with regenerative procedures are now being studied in many medical fields. Despite this，many questions remain about the actual clinical performance of PRF. This review aims to report the current state of clinical potential of PRF in regenerative dental therapy.

Oxytocin was first found to play an important role in lactation and parturition. Recently, oxytocin has been found to have complex functions as a hypothalamic hormone in many tissues in human body, such as promoting bone formation, up-regulating the regeneration of skeletal muscle and maintaining its homeostasis, promoting myocardial development and inhibiting adipose tissue formation. This paper mainly reviews the effect of oxytocin on tissue metabolism, repair and regeneration.

3D printing technology has been developing rapidly in recent years. It was first applied in the engineering field, and then extended to the medical field. In the field of prosthodontics,3D printing technology has made great improvement in the precision of dental prosthesis. This paper reviews the factors that affect the precision of 3D printing prosthesis so that 3D printing technology can be better used in clinic.