氯通道阻断剂NPPB对鸡喙外胚间充质细胞增殖分化影响的研究

目的 氯离子通道阻断剂NPPB对鸡喙外胚间充质细胞(chicken mandibular mesenchymal cells,CMMC)增殖及分化能力的影响。方法 应用MTT、实时定量PCR的方法,观察NPPB阻断氯离子通道后,鸡喙外胚间充质细胞在AA-BGP诱导成骨过程中,细胞增殖及Sox9mRNA、Runx2mRNA及Col10mRNA的表达的变化。结果 在AA-BGP诱导组及无AA-BGP诱导组,NPPB均抑制了CMMC的增殖(P<0.05)。在AA-BGP诱导组及无AA-BGP诱导组,NPPB下调Col10mRNA及Runx2mRNA的表达水平均有显著性差异(P<0.05),Sox9mRNA的表达水平没有显著改变。结论 阻断氯离子通道可抑制鸡喙外胚间充质细胞增殖,并影响细胞向肥大化的软骨细胞分化,可能通过调节Runx2水平影响分化。     

Effects of connective tissue growth factor on human periodontal ligament fibroblasts

ObjectiveThe aim of this study was to evaluate the effects of different concentrations of connective tissue growth factor (CTGF) on human periodontal ligament fibroblasts(HPLFs).DesignHPLFs were cultured and identified. Then, different concentrations of CTGF (1, 5, 10, 50, 100 ng/ml) were added to the HPLF culture. Next, CCK-8 assays, alkaline phosphatase (ALP) assays, hydroxyproline determination, alizarin red staining methods, Transwell chambers and real-time PCR methods were applied to observe the effects of CTGF on the proliferation, ALP activity, synthesis of collagen, formation of mineralized nodules and migration. We also studied expression of ALP, fiber link protein (FN), integrin-binding sialoprotein (IBSP), osteocalcin (OC), and integrin beta 1 (ITGB1) mRNA by HPLFs. Statistical significance was assumed if P < 0.05 or P < 0.01.ResultsThe addition of CTGF (1, 5, 10 ng/ml) remarkably promoted the proliferation and collagen synthesis of HPLFs compared with controls. CTGF (1, 5, 10, 50 ng/ml) improved ALP activity of HPLFs, and at all concentrations, CTGF (1, 5, 10, 50, 100 ng/ml) improved the expression of ALP, FN, IBSP and ITGB1 mRNA. In addition, CTGF (1, 5, 10, 50, 100 ng/ml) promoted the migration of HPLFs, which was dose-dependent, with maximal promotion in the 10 ng/ml group (P < 0.05 or P < 0.01).ConclusionsThus, in a certain range of concentrations, CTGF can promote the biological effects, including proliferation, migration and collagen synthesis of HPLFs, to promote the differentiation of HPLFs in the process of osteogenesis.     

Study on the effects of gradient mechanical pressures on the proliferation,apoptosis, chondrogenesis and hypertrophy of mandibular condylar chondrocytes in vitro

ObjectiveTo investigate the effects of gradient mechanical pressure on chondrocyte proliferation, apoptosis, and the expression of markers of chondrogenesis and chondrocyte hypertrophy.MethodsMandibular condylar chondrocytes from 5 rabbits were cultured in vitro, and pressed with static pressures of 50 kPa, 100 kPa, 150 kPa and 200 kPa for 3 h, respectively. The chondrocytes cultured without pressure (0 kPa) were used as control. Cell proliferation, apoptosis, and the expression of aggrecan (AGG), collagen II (COL2), collagen X (COL10), alkaline phosphatase (ALP) were investigated. Ultrastructures of the pressurized chondrocytes under transmission electron microscopy (TEM) were observed.ResultsChondrocyte proliferation increased at 100 kPa and decreased at 200 kPa. Chondrocyte apoptosis increased with peak pressure at 200 kPa in a dose-dependent manner. Chondrocyte necrosis increased at 200 kPa. The expression of AGG increased at 200 kPa. The expression of COL2 decreased at 50 kPa and increased at 150 kPa. The expression of COL10 and ALP increased at 150 kPa. Ultrastructure of the pressurized chondrocytes under TEM showed: at 100 kPa, cells were enlarged with less cellular microvillus and a bigger nucleus; at 200 kPa, cells shrank with the sign of apoptosis, and apoptosis cells were found.ConclusionsThe mechanical loading of 150 kPa is the moderate pressure for chondrocyte: cell proliferation and apoptosis is balanced, necrosis is reduced, and chondrogenesis and chondrocyte hypertrophy are promoted. When the pressure is lower, chondrogenesis and chondrocyte hypertrophy are inhibited. At 200 kPa, degeneration of cartilage is implied.     

S-nitroso albumin enhances bone formation in a rabbit calvaria model

Nitric oxide (NO) is a mediator involved in bone regeneration. We therefore examined the effect of the novel NO donor, S-nitroso human serum albumin (S-NO-HSA) on bone formation in a rabbit calvaria augmentation model.Circular grooves (8 mm diameter, two per animal) were created by a trephine drill in the cortical bone of 40 rabbits and titanium caps were placed on the rabbit calvaria bone filled with a collagen sponge soaked with either 100 μL S-NO-HSA (5%, 20%) or human albumin (5%, 20%). After 4 weeks the titanium hemispheres were subjected to histological and histomorphometric analysis. Bone formation and the volume of the residual collagen sponge were evaluated.S-NO-HSA treatment groups had a significantly higher volume of newly formed bone underneath the titanium hemispheres compared to the albumin control groups (5%: 15.5 ± 4.0% versus 10.6 ± 2.9%; P < 0.05; 20%: 14.0 ± 4.6% versus 6.0 ± 3.8%; P < 0.01). The volume of residual collagen sponge was also significantly lower in the S-NO-HSA groups compared to the control groups (5%: 0.4 ± 0.5% versus 2.6 ± 2.4%; P < 0.05 and 20%: 1.5 ± 2.7% versus 13.0 ± 18.7%; P < 0.01).This study demonstrates for the first time that S-NO-HSA promotes bone formation by slow NO release. Additionally, S-NO-HSA increases collagen sponge degradation.     

Risk behaviors and their association with presence of S.mutans or S.sobrinus and caries activity in 18-month-old Japanese children

The purpose of this study was to investigate risk behaviors associated with the presence of S. mutans or S. sobrinus and caries activity. The subjects were 448 mother-child pairs who underwent dental health examinations between February 2004 and November 2004 when the children were 18 months old. Caries activity was assessed by the Cariostat test. The presence of S. mutans and S. sobrinus was detected using PCR techniques. Questionnaires regarding risk behaviors were completed by the mothers. A statistically significant correlation was found for the detection of S. mutans and/or S. sobrinus in children and mothers (P < 0.01). High-risk mothers were more likely to have high-risk children (P < 0.001). In children in whom bacteria were detected, breast-feeding was ranked as the most important risk factor (P < 0.01), followed by eating snacks while playing (P < 0.01), getting snacks from neighbors (P < 0.05), being cared for by grandparents (P < 0.05) and pre-chewing of children's food by mothers (P < 0.05). In children with high caries risk, breast-feeding and pre-chewing were the most important risk factors (P < 0.01), followed by taking meals at irregular intervals and mothers not attending maternity classes (P < 0.05).     

Stability of bonds made to superficial vs. deep dentin,before and after thermocycling

ObjectivesBonding stability of resinous adhesives to dentin is still problematic and may involve regional variations in dentin composition. This study is to evaluate the effect of dentin depth on the stability of resin-dentin bonds under thermocycling challenge.MethodsDentin slabs with two flat surfaces parallel to the tooth axis were obtained from extracted human third molars. The slabs were randomized into eight groups according to the location of dentin [deep dentin (DD) or superficial dentin (SD)], the adhesive treatment (Single Bond 2 or Clearfil S³ Bond), and the storage treatment (thermocycling for 5000 times vs. no). After the adhesive treatment and composite buildup on the dentin slabs, the micro-shear bond strength (μSBS) of each group was detected. The concentrations of cross-linked carboxyterminal telopeptide of type I collagen (ICTP) were also evaluated using an immunoassay to detect the degree of collagen degradation in each group.ResultsDentin depth, adhesive treatment and storage treatment all showed significant effects on both the μSBSs and the ICTP values (P < 0.05). Regardless of the adhesive type, thermocycling decreased the μSBSs and increased the ICTP values (P < 0.05). The DD groups showed significantly lower μSBSs and higher ICTP values than SD groups after thermocycling aging (P < 0.05). The treatment with Single Bond 2 significantly increased the ICTP values (P < 0.05), whereas Clearfil S³ Bond showed no effect on the ICTP values (P > 0.05).SignificanceDeep dentin showed significantly more bond degradation after thermocycling than did superficial dentin.     

Preoperative plasma fibrinogen predicts cervical metastasis in patients with stage I/II carcinoma of the tongue

The aim of this study was to evaluate the association of preoperative plasma fibrinogen levels with clinico-pathological parameters and disease-free survival in patients with oral tongue squamous cell carcinoma (OTSCC). We retrospectively studied 76 patients with OTSCC who underwent a partial glossectomy only, at a single centre, between 1996 and 2007. Among the 76 patients, 30 eventually developed cervical metastasis. Preoperative plasma fibrinogen levels were determined and correlated with clinico-pathological findings by t-test or analysis of variance methods. Univariate and multivariate analyses were used to determine the association of preoperative plasma fibrinogen levels and disease-free survival. Elevated levels of plasma fibrinogen were positively related with growth type (P < 0.001), differentiation (P < 0.001), thickness (P < 0.001), and the infiltrative growth ratio (P = 0.032). Univariate analysis showed that growth type (P < 0.001), differentiation (P < 0.001), thickness (P < 0.001), and preoperative plasma fibrinogen levels (P < 0.001) were significantly correlated with disease-free survival. Multivariate analysis showed that the plasma fibrinogen level remained an independent factor for disease-free survival after partial glossectomy for OTSCC (P = 0.029). A high preoperative plasma fibrinogen level is an independent predictor of cervical metastasis after partial glossectomy for OTSCC. A conservative supraomohyoid neck dissection is appropriate in patients with stage I/II carcinoma of the tongue whose preoperative plasma fibrinogen is >300 mg/dl.     

Risk behaviors and its association with caries activity and dental caries in Japanese children

The aim of this study was to assess risk behaviors and its association with caries activity and dental caries in Japanese children. The subjects were 392 young Japanese children who underwent dental health check-up at 18, 30 and 42 months of age. Oral examinations, Cariostat tests and dental health questionnaires were carried out at each time. The caries prevalence of children was 1.5% at 18 months, 9.9% at 30 months and 28.1% at 42 months. Caries activity based on the Cariostat scores of children was correlated with caries status (caries-free/carious) at 42 months. In children with caries during each examination period at 42 months, eating snacks while playing was ranked as the most important behavioral risk (P < 0.001), followed by breast-feeding (P < 0.01), non setting of time for snacks (P < 0.05) and frequency of snacks (P < 0.05) at 18 months old; non brushing by mother (P < 0.05) and eating snacks while playing (P < 0.05) were ranked highest at 30 months old. In addition, eating snacks while playing (P < 0.001) at 42 months old was the only a significant factor for children with caries. Caries activity and risk behaviors were associated with caries experience at different age periods of childhood.     

Clinical comparison of a xenogeneic collagen matrix versus subepithelial autogenous connective tissue graft for augmentation of soft tissue around implants

Dental implant placement is a predictable therapy for replacing teeth. Nevertheless, mechanical, biological, and aesthetic complications frequently occur. The aim of this study was to compare the clinical outcomes of a xenogeneic collagen matrix (XCM) used at the time of implant placement as an alternative to a subepithelial connective tissue graft (SCTG), for soft tissue augmentation. This was a prospective clinical trial with 12 months of follow-up. In the control group, soft tissue augmentation at the time of implant placement was performed with a SCTG, while in the test group, a XCM was employed. At 12 months postoperative, all xenografts showed no postoperative complications. In both groups, a significantly greater thickness was observed on the buccal and occlusal sides from preoperative to 3 months postoperative (P < 0.05). No statistically significant difference in pink aesthetic score (P = 0.379, 6 months postoperative) or marginal bone loss (P = 0.449 at 3 months postoperative, P = 0.778 at 6 months postoperative) was observed between the groups. Statistically significant differences in pain perceived by the patients (P < 0.0001) and the time to complete the surgical procedure (P = 0.0008) were detected. At 12 months after surgery, XCM provided similar clinical results in terms of soft tissue augmentation on the buccal and occlusal sides as compared with the SCTG.     

Hydrogen peroxide induces cell proliferation and apoptosis in pulp of rats after dental bleaching in vivo: Effects of the dental bleaching in pulp

ObjectiveThis study provides an in vivo evaluation of the inflammatory response, levels of cell proliferation and apoptosis, and the presence of necrosis after dental bleaching with two concentrations of hydrogen peroxide (H₂O₂).DesignWistar rats were divided into Control (placebo gel), BLUE (20% H₂O₂, 1 × 50 min), and MAXX (35% H₂O₂, 3 × 15 min) groups. At 2 and 30 days, the rats were killed (n = 10). The jaws were processed for histology analysis and PCNA and Caspase-3-cleaved immunohistochemistry, and data were submitted to the Mann-Whitney or ANOVA test (P < 0.05).ResultsAt 2 days, the MAXX group showed necrosis and the BLUE group revealed moderate inflammation on the occlusal third of the crown (P < 0.05). At 30 days, tertiary dentin had formed and there was an absence of inflammation. The level of cell proliferation was higher in the middle third of the BLUE group (P < 0.05), and cervical of MAXX at 2 days (P < 0.05), decreasing at 30 days. The apoptosis was present at 2 days, particularly in the cervical third of the crown in the bleached groups (P < 0.05), with a decrease only at 30 days in the BLUE group (P < 0.05).ConclusionsThe concentration of H₂O₂ influences effects on the pulp tissue, where a higher concentration of H₂O₂ can cause necrosis in the pulp and a prolonged effect within the apoptotic process; lower concentrations of H₂O₂ provide moderate inflammation, cell proliferation and apoptosis with a reduction of these processes over time.     

Effect of grape seed proanthocyanidins extract on alteration of mechanical properties of metaphysis tibia bone in rats fed a low-calcium diet

The effects of grape seed proanthocyanidins extract (GSPE, 3 mg in 100 g of high-calcium diet with a calcium content of 1697 mg/100 g) on rat metaphysis tibia formation following feeding of a low-calcium diet (30% of calcium in the standard diet) were investigated by examining bone density, mineral content, geometric and bone strength. Five-week old male Wistar rats (n = 40) were randomly divided into a control (Co) group, a low-calcium diet (LC) group, a low-calcium diet • high-calcium diet (LCH) group, and a lowcalcium diet • high-calcium diet with supplementary GSPE (LCHG) group. The metaphysis tibia bones were analyzed using three-dimensional peripheral quantitative computed tomography (pQCT), while whole tibia bones were tested for mechanical resistance using a material testing machine. We found no significant differences in body weight among the 4 groups. All bone parameters in the LC group were significantly lower than these in the Co group (P < 0.01). Furthermore, trabecular bone density (TrBD), trabecular bone mineral content (TrBMC), cross-sectional moment of inertia to the reference axis y (yCSMI), and stress-strain index to the reference axis x (xSSI) in the LCHG group were significantly higher than those in the LCH group (P < 0.05; P < 0.01; P < 0.05; P < 0.05, respectively), while stiffness in the LCHG and LCH groups were significantly higher than that in the LC group (P < 0.01). We concluded that a mixture of high-calcium and GSPE in the diet has a more beneficial effect on bone formation for the treatment of metaphysis tibia bone debility in rats than does a high-calcium diet alone.     

Evaluation of effects of activator treatment on mandibular growth by analyzing components of condylar growth and mandibular rotation

PurposeThe objective of this study is to clarify the effects of activator treatment on mandibular growth in relation to condylar growth and total rotation of the mandible, and to investigate the relationships between the treatment responses and pretreatment facial morphology.Materials and methodsThirty Japanese girls with Class II division 1 malocclusion treated with activator were examined. Mean age at the start of treatment was 9.6 ± 1.6 years. Mean treatment duration was 19 ± 4 months. Lateral cephalograms obtained before and after treatment were used to analyze skeletal changes during treatment. Regional superimposition analysis was performed to evaluate activator effects by decomposing the mandibular growth into condylar growth and mandibular total rotation.ResultsThe changes in intermaxillary relationships were significantly correlated with vertical condylar growth and mandibular total rotation (P < 0.05 and P < 0.01). The changes in the forward displacement of the mandible were significantly correlated with sagittal condylar growth and mandibular total rotation (P < 0.05 and P < 0.01). Vertical condylar growth and mandibular total rotation were significantly correlated with pretreatment mandibular morphology (P < 0.05 and P < 0.01).ConclusionBoth the sagittal condylar growth and counterclockwise mandibular total rotation attributed to activator treatment contribute to forward displacement of the mandible. The activator effects are expected greater in patients with flat mandibular plane, small gonial angle, backwardly inclined mandibular ramus and long posterior facial height.     

Jaw-stretch reflex is weaker in patients after orthognathic surgery

ObjectivesThe jaw-stretch reflex (JSR) was studied in both patients and healthy participants in order to investigate the possible long-term impact of orthognathic surgery on the motor function of the masticatory system.DesignJSR was measured in patients before surgery (PC), 1 year after surgery (PS) and in healthy controls (HC) (N = 31 in each group). JSR was evoked by a standardized stretch device and recorded bilaterally from masseter and anterior temporalis muscles using surface electromyography (EMG).ResultsThe peak-to-peak amplitude (which was normalized to pre-stimulus EMG activity) of JSRs in PC and PS were significantly smaller than in HC (P < 0.001; P < 0.001). The onset latency in PS was significantly longer compared with HC (P < 0.05). The duration of JSR in PS was significantly longer than in HC and PC (P < 0.001; P < 0.05).ConclusionPatients with dentofacial deformities are characterized by reduced JSR amplitude. The delayed onset and elongated duration of JSR might be potential indicators of a long-term surgical impact on the motor function of the masticatory system.     

Cytotoxicity of accelerated white MTA and Malaysian white Portland cement on stem cells from human exfoliated deciduous teeth (SHED): An in vitro study

The aim of this study was to compare the cytotoxicity of accelerated-set white MTA (AWMTA) and accelerated-set Malaysian white PC (AMWPC) on stem cells from human exfoliated deciduous teeth (SHED). The test materials were introduced into paraffin wax moulds after mixing with calcium chloride dihydrate and sterile distilled water. Subsequently, the set cement specimens were sterilized, incubated in a prepared Dulbecco's modified Eagle medium (DMEM) for seven days. The biomarker CD166 was used for characterization of SHED using flow cytometry. The material extracts were diluted at five different concentrations and incubated for 72 h with SHED. The cell viability was evaluated using Dimethylthiazol diphenyltetrazolium bromide (MTT) assay, and the data was analysed using Mann–Whitney test (P<0.05). The results showed that AWMTA revealed significantly greater cell viability at 25 and 12.5 mg/ml concentrations (P<0.05). Concomitantly, AMWPC exhibited greater cell viability at concentrations <12.5 mg/ml and the results were significant at 1.563 mg/ml (P<0.05). Both materials demonstrated moderate cytotoxicity at 25 mg/ml and slight cytotoxicity at 6.25 and 3.125 mg/ml. At 1.563 mg/ml, no cytotoxic activity was merely observed with AMWPC. In conclusion, AMWPC exhibited favourable and comparable cell viability to that of AWMTA, and has the potential to be used as an alternative and less costly material in dental applications.     

Peripheral blood dendritic cells and vascular endothelial growth factor in oral squamous cell carcinoma: correlation analysis and in vitro study

Vascular endothelial growth factor (VEGF) may cause functional deficiency in dendritic cells (DCs) in vitro. The roles of peripheral blood dendritic cells (PBDCs) and VEGF in patients with oral squamous cell carcinoma (OSCC) are not well understood. The authors analysed the correlation between VEGF and PBDC in 81 OSCC patients. They assessed the effect of VEGF on DC function in vitro. VEGF levels were significantly increased in OSCC patients compared with control subjects (P < 0.05), but PBDC levels were significantly lower (P < 0.05). VEGF expression in TNM I–II (67%) and T1–T2 (74%) was significantly lower, compared with TNM III–IV (88%, P < 0.05) and T3–T4 (89%, P < 0.05). Increased VEGF expression in primary tumours was significantly correlated with elevated serum VEGF levels, but reduced PBDC levels. In vitro cultured DC exposed to VEGF showed significantly decreased expression of functional proteins, enhanced endocytosis activity, and elicited weaker proliferation of T cells, compared with that of free VEGF (P < 0.01). These findings suggest that decreased PBDC and elevated VEGF occur in OSCC patients. Higher VEGF levels may affect precursor cells, resulting in decreased numbers of functional DC.     

Effectiveness of green tea mouthwash in comparison to chlorhexidine mouthwash in patients with acute pericoronitis: a randomized clinical trial

The objective of this study was to evaluate the effectiveness of green tea mouthwash in controlling the pain and trismus associated with acute pericoronitis in comparison to chlorhexidine (CHX) mouthwash. Ninety-seven patients with acute pericoronitis underwent debridement and received 5% green tea mouthwash (study group) or 0.12% CHX mouth rinse (control group). Pain (visual analogue scale; VAS), number of analgesics, maximum mouth opening (MMO), and number of patients with trismus were determined. There were no significant differences in demographic variables (P > 0.05), or baseline VAS (P > 0.006), MMO (P > 0.017) or number of patients with trismus (P > 0.017) between the two groups. The mean VAS score of the study group was statistically lower than that of the control group between post-treatment days 3 and 5 (P < 0.006). A significantly lower number of analgesics were taken by the study group (P < 0.05). Although the MMO of the study group was significantly lower on day 3 (P < 0.017), no significant difference was observed on day 7 (P > 0.017). Fewer of the patients rinsing with green tea had trismus on days 3 and 7, but the difference was non-significant (P > 0.017). Hence, green tea mouth rinse could be an appropriate and effective choice for the control of pain and trismus in acute pericoronitis.     

The PI3K/Akt signalling pathway may play an internal role related to abnormal condylar growth: a preliminary study

Developmental deformity of the mandible is one of the most common craniofacial malformations and is closely related to abnormal condylar growth. In this study, the role of PI3K/Akt signalling in the regulation of chondrocyte proliferation and hypertrophic differentiation in the condylar cartilage was studied. Immunohistochemical staining was used to investigate the expression of PI3K and p-Akt in the rat condyle cartilage. Rat condylar chondrocytes were cultured for the investigation of chondrocyte proliferation and hypertrophic differentiation when PI3K/Akt was inhibited. In addition, organ culture of the rat mandibular condyle was performed to evaluate the condyle cartilage growth while PI3K/Akt was inhibited. PI3K-positive cells and p-Akt-positive cells showing cytoplasmic staining were found to be present in the condylar cartilage. Reduced cell proliferation was observed in the culture of rat condylar chondrocytes when PI3K/Akt was inhibited; however, the hypertrophic differentiation level was increased. The proliferative zone thickness of condylar cartilage in the experimental group was less than that in the control group (P = 0.00185), but the hypertrophic zone was greater than that in the control group (P = 0.01048). PI3K/Akt signalling exerts opposite influences on chondrocyte proliferation and hypertrophic differentiation of the condylar cartilage, and these data suggest that PI3K/Akt is a potential intracellular regulation signal pathway in condylar cartilage development.     

Impact of glycemic control on oral health status in type 2 diabetes individuals and its association with salivary and plasma levels of chromogranin A

ObjectiveTo evaluate the effect of glycemic control status in type 2 diabetes mellitus (T2DM) individuals on clinical oral health indicators and to compare the concentrations of plasma and salivary chromogranin A (CHGA) among nondiabetic subjects and T2DM patients, exploring their associations.DesignIn this cross-sectional study, 32 patients with controlled T2DM, 31 with poorly controlled T2DM and 37 nondiabetic subjects underwent a clinical and periodontal examination. CHGA concentrations were determined in saliva and plasma with ELISA.ResultsPoorly controlled T2DM group exhibited significantly higher mean buffering capacity, plaque index and bleeding on probing than other groups (P < 0.05). No difference was found to DMFT (decayed, missed and filled teeth) index between groups. Sites with clinical attachment loss (CAL) of 4 and 5–6 mm were significantly higher in both diabetic groups compared to control group (P < 0.05). Poorly controlled T2DM group had significantly higher sites with CAL ≥ 7 mm than other groups (P = 0.001). Significantly higher plasma and salivary CHGA levels were found in T2DM groups (P < 0.05). In both diabetic groups, probing depths 5–6 mm and CAL 5–6 mm were associated with higher salivary CHGA concentration (P < 0.05).ConclusionsThe findings revealed that T2DM patients were more prone to periodontal tissue damage than to caries risk. The results also provide some evidence that the degree of attachment loss deteriorates significantly with poor glycemic control in T2DM (CAL ≥ 7 mm). Moreover, the results suggest that high concentrations of salivary CHGA are associated with worse periodontal parameters and T2DM, and this could be related to the pathogenesis of both diseases.     

Water sorption and solubility of core build-up materials

ObjectivesTo investigate the variation in water sorption and solubility across a range of different core build-up materials.MethodsFive materials were tested, four of which are resin-based materials (Grandio Core, Core.X Flow, Bright Flow Core, Speedee) and one resin-modified glass ionomer (Fuji II LC). All specimens (n = 10) were immersed in 10 ml distilled water in individual glass containers and weighed at one week, 14 and 28 days. After a total immersion time of 28 days, 7 specimens were dried to a constant mass, in a desiccator for 28 days. Three samples of each material were not dried, but were left in distilled water for 1 year, to determine the long-term water sorption properties. Specimens were weighed at monthly intervals until 6 months and then at the 9th and 12th months. Each specimen was measured using a digital electronic caliper (Mitutoyo Corporation, Japan).ResultsAfter 28 days immersion, the change in water sorption and solubility of the materials ranged from 12.9 to 67.1 μg/mm³ (P < 0.001) and 0.9–6.4 μg/mm³ respectively (P < 0.001). Except for Fuji II LC, an independent T-test showed significantly higher water sorption and solubility for the other materials after 1-year total immersion in water compared to 1 month (P < 0.05). Using repeated measures ANOVA, all materials showed mass changes over time (1 month) (P < 0.001).SignificanceGrandio Core had the lowest water sorption and solubility among the tested materials. According to the ISO 4049 standards, all the tested materials showed acceptable water sorption and solubility, apart from the water sorption behavior of Fuji II LC.     

The alteration of Id-1 and TSP-1 expression in mucoepidermoid carcinoma associated with its clinical features and prognosis

Expression of Id-1 (inhibitors of DNA binding/differentiation protein 1) and TSP-1 (thrombospondin-1) in mucoepidermoid carcinoma and their relationship to pathological features and prognosis was studied. Moderately and poorly differentiated groups had significantly higher Id-1 positive expression rate (p < 0.05) than well differentiated carcinoma. Stages III-IV showed significant increase of Id-1 positive expression rate (p < 0.05) compared with stages I and II. Id-1 positive expression was significantly higher in patients with cervical lymph node metastasis or relapse at 5 years (p < 0.05). After that, patients with negative Id-1 expression had significantly higher tumor-free survival than patients with positive expression (p < 0.05). Correlation between the expression of Id-1 and TSP-1 in mucoepidermoid carcinoma was negative (p < 0.05). Poorly differentiated groups show significantly lower TSP-1 positive expression rate than well differentiated groups (p < 0.05). No significant differences of TSP-1 positive expression were detected with clinical stage. TSP-1 positive expression was significantly lower in patients with cervical lymph node metastasis or relapse at 5 years (p < 0.05). After 5 years, patients with positive TSP-1 expression had significantly higher tumor-free survival than patients with negative TSP-1. Positive Id-1 expression is associated with high malignancy/poor prognosis; positive TSP-1 expression is associated with low malignancy/good prognosis. Protein expression status may help assess tumor malignancy and patient prognosis.