Morphology of the developing articular disc of the human temporomandibular joint

The morphology of the developing articular disc of the temporomandibular joint in eight human fetuses, ranging in age from 13 weeks to 17.5 weeks, was studied. The shape of the articular disc at the time of initial delineation resembled the shape of the adult articular disc, suggesting a predominantly genetic determination. Elastin fibers were not demonstrated. The vascularity of the fetal articular disc was confined to the anterior and posterior thickened peripheral zones, with no evidence of capillaries in the thinner intermediate zone. Lateral pterygoid muscle fibers inserted into the medial aspects of the developing articular disc.     

Comparison of physical properties of polycarboxylate-based and conventional root canal sealers.

Several physical properties of nine commercial root canal sealers were evaluated in vitro and were compared with those of two experimental endodontic materials based on polycarboxylate formulations. Flow, setting time, compressive strength, radiopacity, adhesion to root dentin, and solubility were evaluated. The zinc oxideeugenol root canal sealers were typically of low strength and high solubility. These sealers and the Diaket polyvinyl resin sealer showed no adhesion to dentin. The epoxy resin AH26 showed superior properties with respect to strength, flow, radiopacity, and adhesion; solubility of this material was high. The polycarboxylate formulation showed significantly higher values over the commercial sealers in properties of strength, adhesion, and reduced solubility. The tensile adhesive bond strength of the polycarboxylate to root dentin was twice that of AH26. A wide variation in properties of the commercial materials tested showed the empirical nature of these "sealers." Further testing of polycarboxylate endodontic sealers is indicated.     

Levels of serum immunoglobulin G specific to bacterial surface protein A of Tannerella forsythia are related to periodontal status

Background: Tannerella forsythia (Tf) is a Gram‐negative anaerobe implicated in the development of periodontal disease. Bacterial surface protein A (BspA) is a surface‐expressed and ‐secreted protein that is recognized as an important virulence factor of Tf. This study was undertaken to determine whether Tf BspA induces an antibody response in periodontal disease. We hypothesized that serum immunoglobulin (Ig)G antibody levels against BspA correlate with the disease of patients. Methods: Sera were obtained from 100 patients with cardiac disorders and periodontal disease and 73 patients who experienced myocardial infarction but were periodontally healthy. Sera samples were assayed for anti‐BspA antibody (total IgG and IgG subtypes) by enzyme‐linked immunosorbent assay (ELISA). Antibody levels were measured in ELISA units by using an arbitrary patient as a standard. Results: A negative correlation was found with BspA‐specific total IgG antibody titers and the severity of disease measured as the clinical attachment level (CAL) when healthy and diseased groups were analyzed separately (healthy group: [?0.23, correlation value] Student's t value [73 degrees of freedom] = 1.99; P = 0.05; diseased group: [?0.21] t [100 degrees of freedom] = 2.12; P = 0.03]). However, there was a positive correlation ([0.18 correlation value] Student's t value [173 degrees of freedom] = 2.39; P = 0.017) when healthy and diseased groups were combined. A strong positive correlation ([0.338 correlation value] Student's t value [173 degrees of freedom] = 4.69; P <0.0001) between the BspA‐specific IgG titers and periodontal probing depth was observed when healthy and disease groups were combined. Conclusions: Data demonstrated that antibodies to Tf BspA were elicited in patients with periodontal disease, and antibody levels were associated with the disease severity. Furthermore, data suggested that anti‐BspA IgG might have a protective function in periodontal disease by minimizing the loss of tooth attachment tissue.     

IgG4相关硬化性腮腺炎1例报告及文献复习

通过对1例IgG4相关硬化性腮腺炎疾病的诊治的介绍和相关文献的回顾复习,增加国内口腔科医师对该类疾病的认识,以减少临床误诊误治.     

血清饥饿法对人牙髓细胞周期同步化的研究

目的:探讨不同的血清饥饿方法和饥饿时间对人牙髓细胞(HDPCs)细胞周期的影响.方法:血清直接饥饿和梯度饥饿处理人牙髓细胞.倒置显微镜观察细胞形态;CCK-8检测血清饥饿处理对HDPCs增殖能力的影响;流式细胞术检测细胞周期验证HDPCs同步化的效果.结果:血清直接饥饿处理或梯度饥饿处理后其G0/G1期HDPCs的比例...     

Immunoglobulin G subclass antibody profiles in Porphyromonas gingivalis-associated aggressive and chronic periodontitis patients

BACKGROUND/AIMS: The immunoglobulin G (IgG) antibody response is considered to be protective and beneficial for the control of periodontal lesions. This study analysed IgG subclass antibody levels of Porphyromonas gingivalis in patients with both aggressive periodontitis (AgP) and chronic periodontitis (CP). METHODS: Subgingival plaque and peripheral blood samples were collected from patients with localized AgP (n = 13), generalized AgP (n = 28) and generalized CP (n = 27) and from 14 periodontally healthy controls. P. gingivalis was identified in subgingival pockets using a polymerase chain reaction. Simultaneously, serum IgG subclass antibody against P. gingivalis whole cells/P. gingivalis fimbriae were measured using enzyme-linked immunosorbent assay. RESULTS: P. gingivalis was frequently detected in periodontitis patients. Anti-P. gingivalis whole cell IgG1 was elevated in all P. gingivalis-positive patients in the three periodontitis groups. Although increased anti-P. gingivalis IgG1 was also observed in the bacterium-positive healthy controls, the level was lower than that found in the three periodontitis groups. Levels of IgG1, IgG2, IgG3 and IgG4 to P. gingivalis did not differ among bacterium-positive patients in the three periodontitis groups; a significant increase of IgG2 level was not observed in localized AgP. Anti-fimbriae IgG subclass levels of IgG1, IgG2 and IgG4 did not differ among bacterium-positive subjects in all groups, while the anti-fimbriae IgG3 level in generalized CP was significantly higher than that in localized and generalized AgP. CONCLUSIONS: P. gingivalis infection elicited an IgG subclass antibody response in both periodontitis patients and healthy subjects, while higher anti-P. gingivalis IgG1 levels were found in the three periodontitis groups compared with the healthy control group.     

Immunoglobulin G subclass antibody profiles in Porphyromonas gingivalis‐associated aggressive and chronic periodontitis patients

Background/aims: The immunoglobulin G (IgG) antibody response is considered to be protective and beneficial for the control of periodontal lesions. This study analysed IgG subclass antibody levels of Porphyromonas gingivalis in patients with both aggressive periodontitis (AgP) and chronic periodontitis (CP). Methods: Subgingival plaque and peripheral blood samples were collected from patients with localized AgP (n = 13), generalized AgP (n = 28) and generalized CP (n = 27) and from 14 periodontally healthy controls. P. gingivalis was identified in subgingival pockets using a polymerase chain reaction. Simultaneously, serum IgG subclass antibody against P. gingivalis whole cells/P. gingivalis fimbriae were measured using enzyme‐linked immunosorbent assay. Results: P. gingivalis was frequently detected in periodontitis patients. Anti‐P. gingivalis whole cell IgG1 was elevated in all P. gingivalis‐positive patients in the three periodontitis groups. Although increased anti‐P. gingivalis IgG1 was also observed in the bacterium‐positive healthy controls, the level was lower than that found in the three periodontitis groups. Levels of IgG1, IgG2, IgG3 and IgG4 to P. gingivalis did not differ among bacterium‐positive patients in the three periodontitis groups; a significant increase of IgG2 level was not observed in localized AgP. Anti‐fimbriae IgG subclass levels of IgG1, IgG2 and IgG4 did not differ among bacterium‐positive subjects in all groups, while the anti‐fimbriae IgG3 level in generalized CP was significantly higher than that in localized and generalized AgP. Conclusions: P. gingivalis infection elicited an IgG subclass antibody response in both periodontitis patients and healthy subjects, while higher anti‐P. gingivalis IgG1 levels were found in the three periodontitis groups compared with the healthy control group.     

Longitudinal stability of serum immunoglobulin G responses to periodontal bacteria

BACKGROUND: The value of seroepidemiology in the study of periodontal infections has not been adequately explored. This study examined serum immunoglobulin (IgG) responses to periodontal bacteria in patients with periodontitis and periodontitis-free individuals over a 30-month period. METHODS: Eighty-nine patients with chronic periodontitis and 42 control subjects with no deep periodontal pockets and no or minimal attachment loss (30-72 years old, 43% men) were included. Patients were examined at baseline, after completed periodontal therapy 4 months post-baseline, and at 30 months, and controls, at baseline and 30 months. IgG antibodies to 19 periodontal species were determined by checkerboard immunoblotting. RESULTS: On average, patients displayed at baseline up to 800-fold higher titers than controls to all but three species. Over the 30-month period, titers remained stable at low levels in controls. In patients, periodontal conditions improved from a baseline mean probing depth of 3.6 mm, bleeding on probing of 62% and an average of 21.5 pockets of=6 mm/person, to 2.5 mm mean pocket depth, 30% bleeding on probing, and 1.2 deep pockets, at 30 months. Over time, antibody titers showed a modest decline in patients, but remained significantly elevated at 30 months in comparison with controls. Antibody-level changes over time were not significantly different between subjects that did and did not receive adjunctive systemic antibiotics. CONCLUSIONS: Conspicuous differences in IgG titers to periodontal bacteria exist between periodontitis patients and periodontally healthy controls. Despite successful periodontal therapy, titers remained elevated over a 30-month period, suggesting that serology may mark the history of past periodontal infection.     

The G1 cell cycle arrest of macrophages infected with Aggregatibacter actinomycetemcomitans

Oral Diseases (2010) 16 , 305–309 Objectives: Infection of murine macrophage cell line J774.1 with the periodontopathic bacterium Aggregatibacter actinomycetemcomitans induces apoptotic cell death. The infection induces cell cycle arrest in the G1 phase prior to the appearance of apoptotic cells. This study determined the involvement of various cell cycle‐related signal molecules in A. actinomycetemcomitans‐induced G1 cell cycle arrest. Materials and Methods: Cell cycle in J774.1 cells infected with A. actinomycetemcomitans was analyzed with a flow cytometer. Immunoblot analysis was also employed to determine the expression levels of intracellular signal molecules. Results: Flow cytometric analysis revealed that the percentage of cells in the G1 phase increased to 77.2% at 12 h after A. actinomycetemcomitans infection. Additionally, according to immunoblot analysis, expression levels of hyperphosphorylated forms of retinoblastoma protein (ppRb) declined in J774.1 cells following A. actinomycetemcomitans infection, whereas hypophosphorylated Rb (pRb) expression levels were elevated slightly. Expression levels of cyclin D1 and D2 in the cells decreased gradually postinfection; CDK2, CDK4, CDK6 and cyclin E levels were not changed. Furthermore, postinfection, p21^CIP1/WAF1 expression increased at 6 h, followed by a subsequent decrease. Conclusion: These findings suggest that cyclin D1 and D2 and p21^CIP1/WAF1 participate in G1 cell cycle arrest in A. actinomycetemcomitans‐infected J774.1 cells.     

Infectious hepatitis C, hepatitis G, and TT virus: review and implications for dentists

In the past 10 years, hepatitis C and G viruses have been identified, and in the last two years a further parenterally transmitted agent, termed TT virus (TTV), has been discovered. These viruses have a worldwide distribution and frequently cause chronic infection. The purpose of this article was to promote an understanding of these viral agents and their relevance in dental practice. Infected patients may develop a chronic carrier state without clinical disease or may develop liver disease, and may have related oral conditions. Dental providers will see a growing number of patients with HCV/HGV and possibly TTV infection. All of these patients require appropriate infection control measures during dental treatment.     

The electrochemistry and thin-layer luminescence spectroelectrochemistry of rhodamine 6G at a 4,4′-bipyridine-modified gold electrode

We report on the first direct electrochemistry and fluorescence spectroelectrochemistry of rhodamine 6G at a 4,4′-bipyridine-modified gold electrode. The value of n determined in spectropotentiostatic experiments at 1.87×10^?6 mol l^?1 of rhodamine 6G in 0.20 mol l^?1 KCl solution is 1.15, and the experimental value obtained for E⁰′ is ?0.787 V versus Ag ∣ AgCl ∣ KCl_sat, which agrees very well with the value (E⁰′=?0.791 V) obtained using cyclic voltammetry at a modified gold electrode. The values of the diffusion coefficients D_O and D_R for the oxidized and reduced forms of rhodamine 6G calculated from results of potential step and in situ fluorescence measurement experiments are 4.0×10^?6 cm² s^?1 and 4.2×10^?6 cm² s^?1, respectively. Cyclic voltammograms of rhodamine 6G show that the peak current I_p is proportional to the square root of the potential scan rate v^1/2, the ratio of the reduction to the oxidation peak height is about unity, and the separation of both reduction and reoxidation peak potentials ΔE_P is essentially constant at 135 mV at low scan rates. These results indicate that electrochemistry of rhodamine 6G at a 4,4′-bipyridine-modified gold electrode is a quasi-reversible one-electron electrode process.     

慢性硬化性颌下腺炎IgG4的表达观察

目的 分析慢性硬化性颌下腺炎的临床病理特点及IgG4的表达,为临床诊断和治疗提供参考.方法 收集术后病理诊断为慢性硬化性颌下腺炎的病例9例,男性6例,女性3例,年龄51 ～77岁,中位年龄66岁.对其临床资料、手术标本病理组织学特征及免疫表型总结分析.结果 组织学表现为颌下腺小叶结构保存,致密的淋巴细胞和浆细胞浸润,大量淋巴滤泡反应性增生,腺泡不同程度萎缩,小叶间隔明显纤维化,静脉炎及闭塞性静脉炎形成.免疫组织化学检测显示病变组织中IgG4及IgG阳性的浆细胞均明显增加,每一高倍视野内分别平均为186个和261个,IgG4/IgG为0.71.其中3例患有系统性IgG4相关硬化性疾病.结论 慢性硬化性颌下腺炎是一种IgG4相关硬化性疾病,确诊后应排除是否存在涎腺外的IgG4相关硬化性疾病,并密切随访,类固醇激素治疗效果良好.     

正常人面部表情肌双侧面神经交叉支配神经电图研究

目的：测定面神经各支对侧支配发生率及其EN0G正常值范围,探讨周围性面瘫恢复过程中对侧代偿支配问题,方法：测定了30例正常人同侧及对侧刺激EN0G的潜伏时,持续时间,波幅和最大积分面积,并对面神经各支对侧支配发生率,电反应强弱,同侧与对侧刺激EN0G各指标,对侧刺激各支间EN0G各指标进行分析分析。结果：正常人面神经各支对侧支配发生率不同,I支为67％,II支为0,III,IV支均为100％,各支间电反应强弱不同;左侧刺激右侧记录与右侧刺激左侧记录比较各项指标之间无明显差异,对侧刺激EN0G四项指标I,III,IV支间比较,LT,DT三元无差别,S及AI支均小于III,IV支,IV支之间各项指标间差异无显著性,同侧对侧刺激EN0G各指标间比较各支潜伏时LT,DT同侧与对侧刺激间差异无显著性,S及A对侧刺激均小于同侧刺激,结论：结果：证明了面部表情肌面神经双侧交叉支配的存在,为周围性面瘫恢复机理研究提供了新的依据。