Periodontal diseases and HIV infection

The workshop considered six related questions about periodontal changes seen in HIV infection. 1) To what extent are specific periodontal changes associated with HIV? 2) Are conventional periodontal diseases modified by HIV infection? The changes associated with HIV appear to be modified presentations of conventional diseases. Research should identify initiation and progression factors for necrotizing diseases. 3) What is the role of geography and transmission groups? These questions cannot be answered without greater standardisation of research methods. 4) Has the epidemiology of these changes changed with the advent of new therapies? The data required to answer this question should be available soon but this question is irrelevant to the vast majority of people with HIV. 5) What pathogens are involved in periodontal changes seen in HIV infection? The role of Candida spp. and other potential pathogens requires further investigation. 6) What management protocols are suitable for the periodontal diseases? The significance of periodontal diseases among people with HIV in developing countries is not known. Further research is needed of the effectiveness of interventions especially necrotizing disease in developing countries. The quality of research of these diseases would be enhanced by standardized approaches. A list of relevant variables might prevent their omission from studies.     

Dental curriculum and team treatment concept

The changing oral situation in the Netherlands, the upgrading of the dental hygienist training and the introduction of the bachelor and master degree in the Dutch higher education system asks for a new dental professional: the oral physician. To prepare the oral physician for his role as leader of a dental team several changes and new developments are necessary in the existing dental curriculum.     

口腔微生物致宿主表观遗传改变的研究进展

微生物在感染宿主的过程中能够调控宿主的生理功能,其中一种重要的调控方式是表观遗传调控。表观遗传是指在基因DNA序列不发生改变的情况下, 基因的表达和功能发生稳定改变,并产生可遗传的表型。表观遗传调控在微生物引起宿主免疫反应的过程中起到重要作用。明确微生物对宿主的表观遗传调控机制有利于开展临床靶向治疗,加强表观遗传调节剂的临床应用,为相关疾病防治提供新的策略。该文对几种口腔常见微生物引起的宿主表观遗传改变及相关机制作一综述。     

Periodontitis juvenilis--a new view on the aetiology and treatment

The development of views on the terminology and aetiology, and a new approach to the treatment of juvenile parodontitis are described. The verification of these views has contributed to the explanation of the role of the bacterial factor (Actinomyces actinomycetecomitans) in the development of parodontal changes. This made possible outlining of an optimal therapeutic programmes.     

A new dentist for a new century

The beginning of a new year, a new century and a new millennium, is an opportunity to pause for thought. It provides perspective and a reason to examine again the continuing evolution of dentistry as a profession, and dental education in support of that development. It is an optimal time to re-focus on our role as educators and custodians of the quality of future dental care, as today's students transform into tomorrow's practitioners, responsible over the coming decades for the oral health of a European population exceeding 375 million in the EU alone. Thus, we are aware of formidable responsibilities, and in this age of audit, and accountability for systems and services, it is entirely fitting that the recent scientific meeting of ADEE held in Milan under the Presidency of Professor Antonio Carrassi, took the above title as its theme to augur in the new decade. The Conference Proceedings are published in this issue of the Journal. They provide an exciting overview and indication of the changes ahead and the challenges to dental education.     

MRI and MRS diagnosis. Application in multiple sclerosis patients and research animals with experimental allergic encephalomyelitis

MR imaging and spectroscopy offer a noninvasive way to observe lesions and biochemical changes, respectively, that may provide new insights into demyelinating diseases such as MS. Although the role and importance of some of the metabolites, such as choline and N-acetyl aspartate in brain function and disease are not fully understood, the specificity of these changes may provide information about the stage and reversibility of the brain lesions. Animal studies are particularly insightful when MR spectroscopic signals are correlated with histologic and biochemical techniques. Clinical application of spectroscopic imaging could arise from the capability to differentiate between early lesions that might respond to therapy and older irreversible lesions. Although more data need to be obtained, MR spectroscopy shows promise for monitoring progression of MS and evaluating therapy.     

Pharmacogenomics in oral diseases

The availability of newer technologies for identification and characterization of the human genome has enabled our understanding of the genetic variations in a majority of human diseases. Human genomic sequence varies in less than 1% among the different population group and these differences known as gene polymorphisms are the primary reasons for differences in individuals’ response to various drug therapy. Also understanding the genetic changes may enable implementation of targeted therapy, thus providing for effective treatment strategies and minimizing the adverse side effects. Pharmacogenomics is a recent development in the field of personalized medicine which focuses on the genetic determinants of drug response at the levels of entire human genome. It primarily deals with tailoring of drug therapy for every individual based on their genetic make-up and identifying new target in various diseases for drug therapy. While the application of pharmacogenomics in systemic illness is well researched, its role in oral diseases needs documentation. Identifying specific targets in periodontitis, head and neck cancer, infections and genetic disorders can be beneficial in discovery of new drugs. This editorial provides an overview of basics of pharmacogenomics, its current role in disease management and its potential role in various head and neck diseases.     

TNF-α/ NF-κB信号通路对牙周炎发展和牙周再生的影响及其干预

牙周病是以菌斑微生物为始动因子的感染性疾病,菌斑微生物可刺激宿主细胞产生炎性和免疫因子,其中肿瘤坏死因子-α（tumor necrosis factor alpha,TNF-α）作为一个多向性的先导感染细胞因子,在牙周炎的发生、发展过程中起重要作用,同时也是牙周再生的重要影响因素。龈沟液中TNF-α水平的变化已经被用来作为牙周炎治疗的效果以及判断预后的重要指标,越来越多的研究开始关注以TNF-α作用过程为靶点探讨牙周炎发展控制和牙周再生促进的有效方法。本文就TNF-α/NF-κB信号通路对牙周病发展和牙周再生的影响及其干预治疗现状作一综述,以期为牙周病治疗提供新思路。     

The human lateral pterygoid muscle: a review of some experimental aspects and possible clinical relevance

The clinical notion that some disturbance to the activity of the lateral pterygoid muscle plays a role in the aetiology of temporomandibular disorders (TMD) is still widely accepted and influences management strategies. However, there is no rigorous scientific evidence to support this clinical notion and the role of the lateral pterygoid muscle in normal function is still controversial. The classically defined functions of each head of the muscle are that the superior head is active on closing, retrusion, and ipsilateral jaw movements, while the inferior head is active on opening, protrusion and contralateral jaw movements. However, recent data indicate that these concepts are too simplistic. For example, recent evidence suggests that parts of the superior head may also be active on opening, protrusion and contralateral jaw movements, and that the superior head may consist of three mediolaterally arranged functional zones. Given these complexities, the proposal that clicking and/or locking conditions arise in the temporomandibular joint through some form of lack of co-ordination between the two heads of the muscle needs re-evaluation. Despite earlier reports to the contrary, both heads of the lateral pterygoid muscle appear to be electrically silent at the postural or resting jaw position, and therefore appear to play no role in the anteroposterior positioning of the jaw at the postural position. An important role has also been demonstrated electromyographically for progressive changes in activity in the inferior head as the direction of horizontal jaw force shifts from one side to the other. This suggests an important role for the lateral pterygoid muscle in the generation of side-to-side and protrusive jaw forces. The lateral pterygoid muscle is likely therefore to play an important role in parafunctional excursive jaw movements and also possibly a role in influencing jaw position in patients where the maxillomandibular relationship records change from session to session. The above data provide new insights into the normal function of the lateral pterygoid muscle. The proposal that the lateral pterygoid muscle plays some role in the aetiology of TMD needs now to be rigorously tested.     

Neural modulation of inflammatory reactions in dental tissues incident to orthodontic tooth movement. A review of the literature.

This article reviews the current knowledge of the biological aspects of dental tissue changes incident to orthodontic tooth movement. The inflammatory nature of these tissue changes was first recognized in the early 1970s, and since then a number of morphological and quantitative investigations have been published in support of this view. The studies dealing with vascular and cellular dental tissue changes, as well as those concerned with inflammatory mediators present at sites of orthodontic tooth movement are systematized and presented accordingly. Special emphasis is placed upon the role of the sensory nerve fibres and their neuropeptides in the control, and development of an inflammatory process, i.e. their role in tooth movement.     

Dentistry and health policy

Views expressed from several quarters of the health care system suggest that a reexamination of health policy concerning how health care is organized is likely in the next few years. The last time that a reorganization of health care occurred in the United States, dentistry was not included in a major component (Medicare). A review of the profession's stand at that time, and changes in demography of the elderly population since then, suggests that the position of the profession arrived at in the 1960's needs to be reexamined. The time to discuss what the position of dentistry should be in a new policy debate is now. Alternative approaches responding to economic considerations in the oral health care of the elderly are presented to stimulate discussion about the role of dentistry in health advocacy, both for the elderly and the population at large.     

Relationship between mucositis and changes in oral microflora during cancer chemotherapy

It is thought that the incidence and severity of cancer chemotherapy-associated mucositis is caused in part by changes in the oral bacterial microflora. This systematic review examined the role of oral bacterial microflora changes in the development of oral mucositis during chemotherapy. Thirteen prospective clinical trials were identified, involving 300 patients with 13 different cancer diagnoses. There was great variability in patient populations, bacterial sample collection methodology, and oral sample sites. No clear pattern regarding qualitative and quantitative oral flora changes emerged among these studies. The most frequent Gram-negative species isolated during chemotherapy were from the Enterobacteriaceae family, Pseudomonas sp. and E. coli. The most common Gram-positive species isolated were Staphylococcus sp. and Streptococcus sp. Five studies assessed the role of oral flora changes in the genesis of oral mucosal changes, with no consensus among them. More detailed studies are required to understand the relationship between chemotherapy, alterations in the nature and magnitude of the oral microflora, and the presence of mucositis.     

Clinical practice of the future. The future of dentistry.

The last 20 years have brought enormous change to the dental profession. The American Dental Association Future of Dentistry Report examines some of these advancements and discusses what changes to anticipate in the future. Among the most significant changes are those that will occur in the scope of clinical dental practice. This is largely due to anticipated shifts in patient demographics, provider availability, advancements in science and technology, and a changing role for the dentist in the health care community. Future dentists will maintain their role as experts on diseases of the oral cavity. However, their responsibilities will change and increase as they observe the interaction between oral and systemic health. Dental education, therefore, must reflect the changing role of the dentist.     

The role of type X collagen in facilitating and regulating endochondral ossification of articular cartilage

AUTHOR: Shen G Objective -This review was compiled to explore the role of type X collagen in growth, development and remodeling of articular cartilage by elucidating the linkage between the synthesis of this protein and the phenotypic changes in chondrogenesis and the onset of endochondral ossification. DESIGN: The current studies closely dedicated to elucidating the role of type X collagen incorporating into chondrogenesis and endochondral ossification of articular cartilage were assessed and analyzed to allow for obtaining the mainstream consensus on the bio-molecular mechanism with which type X collagen functions in articular cartilage. RESULTS: There are spatial and temporal correlations between synthesis of type X collagen and occurrence of endochondral ossification. The expression of type X collagen is confined within hypertrophic condrocytes and precedes the embark of endochondral bone formation. Type X collagen facilitates endochondral ossification by regulating matrix mineralization and compartmentalizing matrix components. CONCLUSION: Type X collagen is a reliable marker for new bone formation in articular cartilage. The future clinical application of this collagen in inducing or mediating endochondral ossification is perceived, e.g. the fracture healing of synovial joints and adaptive remodeling of madibular condyle.     

Trends in medical education*

Undergraduate medical education in the United Kingdom is undergoing major changes. These changes are the result of pressures from three different but interrelated areas. Alterations in the funding and management of higher education and health care, new approaches to curriculum design and advances in clinical practice each have significant impact on how medical education is delivered. Students, teachers, medical schools and hospital and community practice are all affected by these changes.     

Angiogenesis in oral cancer.

Head and neck squamous cell carcinoma (HNSCC) is an aggressive malignancy that develops after years of chronic exposure to alcohol and tobacco products. Exposure to these agents results in alterations of genes that are important in the regulation of various cellular functions. This loss of regulation allows the tumor cells to survive and grow in an unchecked manner by allowing the cells to perform functions that contribute to the growth of the tumor. Some of these important changes include the acquisition of immortality and the ability to invade tissue and/or metastasize to other sights, as well as acquiring the ability to induce angiogenesis. Angiogenesis, the growth of new blood vessels from pre-existing ones, is a complex phenomenon that is absolutely required for the continued growth and survival of solid neoplasms. Without new blood vessels to provide nutrients and remove waste, tumors would be unable to grow larger than 2-3 mm in diameter. Therefore, one could envision its potential role in both the treatment and prevention of malignancies such as HNSCC. The concept of chemoprevention is extremely important in HNSCC since patients often develop multiple independent lesions throughout the mucosa of the upper aerodigestive tract. Therefore, the comprehensive treatment of this disease must address not only the initial primary neoplasm, but also prevent the progression of the premalignant lesions lurking throughout the rest of the mucosal surfaces. This review will outline the basic changes that occur in tumor cells that result in the switch to angiogenic phenotype. In addition, it will discuss the present status of using antiangiogenic agents in the treatment of cancer. Finally, this paper will present a rationale for the use of multiple antiangiogenic agents as a means of developing new chemotherapeutic and chemopreventive protocols that may result in reduced patient toxicity while maintaining similar clinical efficacies.     

面部初级感觉和运动皮层在口腔环境改变时的神经可塑性研究进展

大脑中与感觉、运动、学习、语言和认知有关的系统都集中于大脑皮层,面部初级感觉和运动皮层在控制颌面运动功能时发挥重要作用。口腔环境改变时,可以引发初级感觉和运动皮层结构改变及功能重组,初级感觉和运动皮层的神经可塑性反应了神经系统对新环境的适应能力。大脑皮层中初级感觉和运动皮层的神经可塑性研究对于揭示大脑活动规律、实施临床矫治和干预均具有重要意义。     

The role of sucrose in cariogenic dental biofilm formation--new insight

Dental caries is a biofilm-dependent oral disease, and fermentable dietary carbohydrates are the key environmental factors involved in its initiation and development. However, among the carbohydrates, sucrose is considered the most cariogenic, because, in addition to being fermented by oral bacteria, it is a substrate for the synthesis of extracellular (EPS) and intracellular (IPS) polysaccharides. Therefore, while the low pH environment triggers the shift of the resident plaque microflora to a more cariogenic one, EPS promote changes in the composition of the biofilms' matrix. Furthermore, it has recently been shown that the biofilm formed in the presence of sucrose presents low concentrations of Ca, P(i), and F, which are critical ions involved in de- and remineralization of enamel and dentin in the oral environment. Thus, the aim of this review is to explore the broad role of sucrose in the cariogenicity of biofilms, and to present a new insight into its influence on the pathogenesis of dental caries.     

Proposed methods for improving the efficiency of the DMFS index in assessing initiation and progression of dental caries

Abstract Recent changes in the epidemiology of dental caries and advances in the development of new diagnostic measurement techniques have stimulated interest in improved methods of assessing changes in dental caries status. Traditional methods for assessing change focus primarily on the development of new lesions at the cavitation level and incorporate incomplete information on the progression of existing cavitated lesions. A methodology to expand the clinical recording of dental caries in clinical studies to include 1) both non-cavitated and cavitated lesions and 2) the surface area affected for restorations is suggested. New indices are proposed to estimate changes in the number of new lesions, the progression of existing carious lesions, and the total change in caries status for a subject. It is anticipated that the new indices will produce more efficient methods of assessing change in caries status in longitudinal clinical studies. The degree of improvement can be estimated directly. Improvements in efficiency may reduce the duration or number of subjects required in caries clinical trials.