Mood and malignancy: head and neck cancer and depression

Head and neck cancer patients have been reported to show high rates of depression. However, it is important to differentiate between depressive symptoms and a depressive disorder. This review critically examines the relationship between head and neck cancer and depression. There appears to be little evidence for depression leading to an increased risk of developing cancer and although depressive symptoms in head and neck cancer patients are common, very few studies have investigated depressive disorders. The studies that investigated the incidence of a comorbid depressive disorder report a prevalence very close to that of the general population, implying that major depression is not a normal response to cancer. Finally, the evidence suggests that comorbidity of depression with cancer has a negative impact on morbidity and mortality. Both psychosocial and biological factors could account for this. Dysregulation of the stress hormone axis and increased inflammation are common in depressive disorders and have been suggested as underlying pathological mechanisms and are both markers of poor prognosis in cancer. This evidence suggests that a relatively small number of patients develop a depressive disorder following a diagnosis of cancer, but for those that do it may have a substantial impact on their prognosis.     

低氧和自噬与肿瘤的发生发展

自噬作为真核生物的一种应激调控机制,既可以促进肿瘤的发生发展,又可以抑制肿瘤的增殖。在肿瘤局部低氧的微环境下,低氧诱导因子-1α、哺乳动物雷帕霉素靶蛋白信号转导通路抑制、内质网应激均可促进自噬的发生。在肿瘤快速地发生发展过程中,肿瘤的糖代谢功能增强、活性氧族增多、窖蛋白1下调以及上皮间质转化的激活均诱导了自噬的发生并促进肿瘤的局部浸润、侵袭转移和耐药,因此,抑制自噬可能为肿瘤治疗提供一种新的策略。     

补体与牙周炎发生发展及其治疗

在牙周炎这一慢性炎症反应过程中,补体不仅可以调解机体防御反应,保护宿主,还可直接作用于免疫细胞或通过调控信号转导通路,协助病原菌进一步感染和破坏牙周组织,最终导致免疫病理性的损伤反应。在免疫炎症反应中,补体不仅可刺激白细胞分泌白细胞介素、肿瘤坏死因子和粒细胞-巨噬细胞集落刺激因子,调节辅助性T细胞和巨噬细胞,促进细胞免疫和T细胞依赖的抗体分泌,增强免疫效应的调节,提高机体免疫力;亦可引起的炎症反应可对组织造成损伤,引起牙周炎。以补体受体拮抗剂干扰补体受体-Toll样受体信号转导通路,有利于机体清除病原菌,达到防治牙周炎的目的。理解补体在牙周炎发生发展中的作用,可为牙周炎治疗探索新途径。     

Molecular biology and its applications in orthodontics and oral and maxillofacial surgery

Molecular biology is an exciting, rapidly expanding field, which has enabled enormously greater understanding of the biology of diseases and malfunctions in many fields. It chiefly concerns itself with understanding the interactions between the various systems of a cell, including the interrelationship of DNA, RNA and protein synthesis and how these interactions are regulated. Since the introduction of molecular biology into modern science, numerous other fields have been enabled to go ““molecular““. Advanced molecular biological techniques showed us new avenue towards finding answers to the questions asked for decades. The first part of this article described the history of molecular biology. It started as a joined discipline of other areas of biology, i.e. genetics and biochemistry in the 1930s and 1940s, and enjoyed its classical period and became institutionalized in the 1950s and 1960s. Major molecular techniques manipulating proteins, DNA and RNA were introduced and their mechanisms were concisely illustrated. The current knowledge of molecular biology and their applications in orthodontic and oral and maxillofacial surgery, i.e. osteoclast differentiation and function, regulation of tooth movement, mechanotransduction/cell-signalling, bone fracture healing, oral cancer as well as craniofacial/dental anomalies and distraction osteogenesis were discussed. Although the problems of introducing molecular technologies are still substantial, it is anticipated that the future of medicine/dentistry will be ““molecular““: molecular prevention, molecular diagnosis and molecular therapy.     

成釉细胞瘤、颌骨囊肿中E-cadherin、vimentin的表达及意义

目的通过免疫组化双染技术检测成釉细胞瘤(ameloblastomas,AM)、颌骨囊肿中E-cadherin、vimentin的表达情况,探索AM中是否存在上皮间充质转化(epithelial-mesenchymal transition,EMT)现象。方法选择37例不同分型的AM、5例颌骨囊肿为研究对象,用免疫组化双染技术检测E-cadherin、vimentin的表达情况,通过计数分析二者共同表达细胞的分布情况。单因素方差分析AM与颌骨囊肿、实性型与单囊型AM的EMT。结果 AM中存在EMT现象,EMT发生特点在实性型与单囊型AM之间、AM与颌骨囊肿之间均无统计学差异。结论 EMT与成釉细胞瘤的侵袭性生物学行为无相关性,EMT存在于AM中可能为肿瘤组织中间质细胞的来源之一。     

VEGF及受体在颌面部血管瘤和血管畸形中表达及意义

目的 检测细胞因子血管内皮生长因子(VEGF),血管内皮生长因子受体(VEGFR/KDR)及VEGF mRNA在颌面部血管瘤和血管畸形中的表达,探讨VEGF及其受体与血管瘤发病机制的关系。方法 采用二步EnVision免疫组织化学方法,分别检测27例血管瘤和15例血管畸形组织中VEGF和VEGF/KDR表达;同时采用原位杂交Gene Point法检测VEGF mRNA的表达。结果 VEGF和VEGFR/KDR在血管瘤中高表达,而在血管畸形组中低表达,两者有显著差异(P<0.01);VEGF和VEGF mRNA在血管瘤细胞及周围间质细胞明显表达,VEGFR/KDR主要表达于血管瘤中内皮细胞膜上。结论 VEGF可通过自分泌和旁分泌的形式影响血管瘤内皮细胞的增殖,可能与血管瘤发生、发展和退化有密切相关。     

钙磷再矿化及其系统

龋病是一种釉质脱矿与再矿化作用失衡,牙体硬组织向脱矿方向持续发展的疾病。当口腔内钙和磷酸根离子饱和度下降时,釉质脱矿;反之,釉质再矿化;因此,钙和磷酸根离子是再矿化的物质基础,钙磷离子浓度越高,越有利于釉质再矿化的发生。无定形钙磷（ACP）能与氟离子结合生成无定形钙磷氟（ACPF）,ACP和ACPF能向口腔环境提供可利用的钙磷和氟离子,促进釉质的再矿化;但亦降低可利用的钙、磷酸根和氟离子浓度,降低其促再矿化能力。酪蛋白磷酸肽（CPP）与钙和磷酸根以一种微弱的化学力结合,使得CPP-ACP复合体中的钙、磷酸根离子与口腔环境中的游离钙、磷酸根离子间保持一种动态平衡。当pH值较高时,大量钙、磷离子以CPP-ACP形式存在;随着pH值降低,CPP-ACP释放出钙、磷酸根离子促进釉质再矿化。CPP-ACP有效定位于龋损表层及表层下并释放钙和磷酸根离子,具有良好的促再矿化效果。氟具有良好的再矿化防龋效果,可通过与CPP-ACP中的氢氧根离子置换生成CPP-ACPF。CPP-ACPF通过附着于牙体表面或顺CPP-ACPF浓度梯度渗透进入釉质龋坏表层下,持续释放钙、磷酸根和氟离子,促进釉质表层和表层下再矿化。     

种植体周围炎与牙周炎的类比探究

种植体周围炎症是种植失败的主要原因之一,包括种植体周围黏膜炎和种植体周围炎。种植体周围炎的发生、发展及治疗和预防与牙周炎存在一定的相似性,本文将种植体周围炎和牙周炎的流行病学、组织病理表现、始动因素、危险因素、治疗和预防等方面进行类比,探讨如何更好地预防和治疗种植体周围炎。     

Coronal and root caries incidence and increments

This study reprots on coronal and root caries incidence in elderly lowans between 1987 and 1988. The sample consisted of 74 survivors ofthe lowa 65+Oral Health Study cohort who recieved oral examinations both who recieved oral examinations both in 1987 and between 1996‐98. The study found that average untreated coronal and root increments were 0.96 and 0.69 surfaces, filled increments were 18.22 and 1.28 surfaces, and combined increments were 18.3 and 1027 sufaces, respectively. Therefore. annualized untreated coronal and root increments were 0.10 and 1.07 surfaces, filled were 1.80 and 0.13 surfaces, and combined increments were 1.81 and 0.12 surfaces, respectively. The annualized attack rates were 2.13 for coronal and 0.80 for root caries. Approximately 93% of the subjects developed some new coronal and 43% some new root caries increment. Dental caries still constutute a significant problem since a large proportion of the elderly developed caries during this period. This suggests a need for improved preventive and treatment strategies for this aged population.     

Differences between and within human parotid saliva and nasal mucus cAMP and cGMP in normal subjects and in patients with taste and smell dysfunction

J Oral Pathol Med (2010) 40 : 504–509 Background: We previously described some of the moieties in human saliva and nasal mucus including cyclic nucleotides. However, comparison of levels of these latter moieties in saliva and nasal mucus has not been performed and meaning of differences found has not been discussed. Purpose: To compare the levels of cAMP and cGMP in saliva and nasal mucus and to describe the differences in their concentrations and function. Methods: cAMP and cGMP in saliva and nasal mucus were compared in normal subjects and patients with taste and smell dysfunction by use of a spectrophotometric colorimetric ELISA. Results: Both cAMP and cGMP were present in saliva and nasal mucus of normals and patients with levels of both moieties lower in patients than in normals. In normals, cAMP is 6½ times higher in saliva than in nasal mucus whereas cGMP in nasal mucus is 2½ times higher than in saliva. In patients, these differences persist but are less robust. In normals, within saliva, cAMP is 9½ times higher than cGMP whereas within nasal mucus cAMP is half the level of cGMP. In patients, within saliva, these differences persist but at variable differences. Conclusions: Both saliva and nasal mucus cAMP and cGMP play roles in taste and smell function, and differences in their concentrations may offer insight into these roles. In nasal mucus, cGMP may be more relevant than cAMP in activity of olfactory epithelial cell function. In saliva, cAMP may be more relevant as a growth factor in taste bud function than cGMP.     

Clinical and microbiological effect of scaling and root planing in smoker and non-smoker chronic and aggressive periodontitis patients

OBJECTIVES: To compare the effects of scaling and root planing (SRP) on clinical and microbiological parameters at selected sites in smoker and non-smoker chronic and generalized aggressive periodontitis patients. MATERIALS AND METHODS: Clinical parameters including probing depth (PD), relative attachment level (RAL), and bleeding upon probing (BOP), and subgingival plaque samples were taken from four sites in 28 chronic periodontitis (CP) and 17 generalized aggressive periodontitis (GAgP) patients before and after SRP. Polymerase chain reaction assays were used to determine the presence of A. actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia and Treponema denticola. RESULTS: Both CP and GAgP non-smokers had significantly greater reduction in pocket depth (1.0+/-1.3 mm in CP smokers versus 1.7+/-1.4 mm in non-smokers, p=0.007 and 1.3+/-1.0 in GAgP smokers versus 2.4+/-1.2 mm in GAgP non-smokers, p<0.001) than respective non-smokers, with a significant decrease in Tannerella forsythensis in CP sites (smokers 25% increase and non-smokers 36.3% decrease, p<0.001) and Prevotella intermedia at GAgP sites (smokers 25% reduction versus 46.9% in non-smokers, p=0.028). CONCLUSION: SRP was effective in reducing clinical parameters in both groups. The inferior improvement in PD following therapy for smokers may reflect the systemic effects of smoking on the host response and the healing process. The lesser reduction in microflora and greater post-therapy prevalence of organisms may reflect the deeper pockets seen in smokers and poorer clearance of the organisms. These detrimental consequences for smokers appear consistent in both aggressive and CP.     

骨性下颌偏斜及其诊治

骨性下颌偏斜是临床上较少见的一种疾病,严重影响患者的颌面美观和功能。本文就该疾病的病因、诊断和治疗等研究进展作一综述。     

Diagnosis and management of hemangiomas and vascular malformations of the head and neck

Oral Diseases (2010) 16 , 405–418 Vascular anomalies are congenital errors in vascular development. They frequently involve the head, neck, and oral cavity. Subdivided into vascular tumors (hemangiomas) and vascular malformations, vascular anomalies remain poorly understood. However, growing interest and recent advances in the diagnosis, management, and molecular characterization of these lesions are improving treatment strategies. The role of the multidisciplinary team cannot be overstated. This review provides both basic and up‐to‐date knowledge on the most common vascular anomalies encountered by physicians and practitioners. Because treatment options for vascular anomalies are widely variable and often debated, this report aims to provide a comprehensive approach to these lesions based upon current concepts and practical clinical experience.     

Calcium- and hydroxyapatite-binding properties of glucuronic acid-rich and iduronic acid-rich glycosaminoglycans and proteoglycans

This study describes the interaction of a small chondroitin sulphate proteoglycan and the glycosaminoglycans chondroitin 4-sulphate, dermatan sulphate and heparan sulphate with hydroxyapatite. All macromolecules possessed a high affinity, with the iduronic acid-rich dermatan sulphate and heparan sulphate displaying higher adsorption maxima than the glucuronic acid-rich chondroitin 4-sulphate. At similar concentrations, dermatan sulphate produced a 30% inhibition of hydroxyapatite-induced crystal growth, whilst chondroitin 4-sulphate yielded 50% inhibition. Estimation of the calcium binding capacity of these glycosaminoglycans using equilibrium dialysis indicated that chondroitin 4-sulphate bound five times more calcium than dermatan sulphate at a calcium concentration similar to that of serum. The data indicate a possible important role for chondroitin 4-sulphate in dentinogenesis where it is the dominant glycosaminoglycan, since it could act as a capture point for calcium ions during mineralisation, with the leucine-rich domain of its parent proteoglycan acting as anchor points to type I collagen.     

对口腔诊室中飞沫和气溶胶的认知与感染防控措施

口腔操作因喷溅可产生大量飞沫,进而转化为飞沫核以气溶胶的形式悬浮留存于诊室空气中。飞沫和气溶胶均可能携微生物造成院内的污染,对临床医护人员及患者健康造成潜在威胁。本文通过对生物气溶胶研究领域涉及的一些概念和口腔诊室飞沫和气溶胶的干预措施进行文献回顾和梳理,以明晰现有文献资料中是否有气溶胶携菌的试验证据,为传染病疫情期间口腔临床工作的防控策略制定提供指导,也为日常口腔诊疗工作的院感管理和防控措施的实施提供参考。     

Tribocorrosion and oral and maxillofacial surgical devices

The release of metal ions or material particles, or both, into tissues that surround implanted medical or dental devices can create postimplantation complications. These rare but disturbing events are mainly caused by the mechanical movements of the components of the implant against each other, coupled with the influences of local biochemical and electrochemical factors. Mechanical movement of the components of implants against each other results in friction and wear, the study of which is called tribology. The tribology of an implanted device depends on the patient's activity and is affected by variables such as load, frequency, and the surface properties of the components of the implant that are in contact. Local biochemical and electrochemical factors include the ambient pH, and concentrations of protein and oxygen. The effect on local tissues and extracellular fluid can produce biochemical or electrochemical responses to the implant material in the surrounding solution, which is termed corrosion. The combined effect of these mechanical, biochemical, and electrochemical factors is known as tribocorrosion.     

Oral adhesion and survival of probiotic and other lactobacilli and bifidobacteria in vitro

INTRODUCTION: Most probiotic products are consumed orally and hence it is feasible that the bacteria in these products may also attach to oral surfaces; however, the effects of these bacteria on the oral ecosystem are mostly unknown. Our aim was to evaluate the oral colonization potential of different probiotic, dairy, and fecal Lactobacillus and Bifidobacterium strains in vitro. METHODS: The binding of 17 Lactobacillus and seven Bifidobacterium strains to hydroxyapatite and microtitre wells coated with human saliva was tested. Binding of selected strains to human buccal epithelial cells and co-adherence with Fusobacterium nucleatum were also investigated. In addition, the survival in sterilized human whole saliva was examined. RESULTS: There was a large variation in binding to saliva-coated surfaces and buccal epithelial cells but all strains survived in saliva. The binding pattern of the probiotics did not differ from the binding of the fecal strains. F. nucleatum altered the binding of both the low-binding bifidobacteria and the high-binding lactobacilli. CONCLUSION: The differences in binding in vitro may indicate that there are also differences in the persistence of the different probiotic strains in the oral cavity in vivo.     

Twins and twinning, dentists and dentistry

Comparisons of physical features within identical (monozygous) and non-identical (dizygous) twin pairs have provided valuable insights into the relative contributions of genetic and environmental influences to observed variability. The special nature of the twinning process itself also provides an opportunity to learn more about early human development, including how body symmetry is determined. The mechanisms of twinning, mortality and morbidity in twins, determination of body symmetry including the phenomenon of mirror-imaging, postnatal growth and development of twins, and zygosity determination are discussed. Twin studies with direct relevance to clinical dentistry are reviewed and illustrated by examples from an ongoing investigation of dentofacial morphology in South Australian twins.     

��ʹ������ԭ�򼰷���

牙拔除术是一种常见的外科手术,术后因机体对拔牙创伤的生理反应会不可避免地引起局部出现程度不一的疼痛、肿胀,这种由手术创伤引起的疼痛、肿胀虽然是正常手术的继发过程,但会导致患者术后生活质量下降,并可使很多由于恐惧而不敢拔牙的患者延误了最佳治疗时机。本文就拔牙术后疼痛和肿胀的发生原因、临床表现、治疗方法和预防措施进行阐述,为临床上如何避免或减轻拔牙术后的疼痛和肿胀提供帮助。