Periodontopathic bacterial infection in childhood

BACKGROUND: Little information is available on periodontopathic bacterial infection in childhood. We assessed the prevalence by age of 10 putative periodontopathic microorganisms in periodontally healthy children using a polymerase chain reaction (PCR) assay. METHODS: Plaque samples were collected from the buccal-mesial sulcus of the first molar or second primary molar in the right upper quadrant of 144 children (2 to 13 years old, 12 subjects from each year of age) who showed negligible periodontal inflammation. Using species-specific primers of Porphyromonas gingivalis, Bacteroides forsythus, Prevotella intermedia, Prevotella nigrescens, Campylobacter rectus, Eikenella corrodens, Actinobacillus actinomycetemcomitans, Capnocytophaga ochracea, Capnocytophaga sputigena, and Treponema denticola, PCR amplification was performed with bacterial genomic DNA from plaque samples. RESULTS: The results indicated that C. rectus, E. corrodens, A. actinomycetemcomitans, C. ochracea, and C. sputigena were found in about 50% of the plaque samples from all age groups, while B. forsythus and P. intermedia were detected less frequently, and P. gingivalis and T. denticola were not found. In contrast, the percentage of P. nigrescens-positive subjects increased with age in primary dentition, and reached about 50% at 7 years of age and older. Subject-based analyses suggested that the number of bacterial species in the plaque samples increased gradually with age until 5 years old, and then reached a plateau after the mixed dentition period. CONCLUSIONS: The colonization of many putative periodontopathic microorganisms can occur quite early in childhood without clinical signs of periodontal disease. However, colonization by P. gingivalis and T. denticola was not detected in periodontally healthy children.     

Impact of cannabis sativa (marijuana) smoke on alveolar bone loss: a histometric study in rats

Background: Cannabis sativa (marijuana) can interfere with bone physiopathology because of its effect on osteoblast and osteoclast activity. However, its impact on periodontal tissues is still controversial. The present study evaluates whether marijuana smoke affects bone loss (BL) on ligature‐induced periodontitis in rats. Methods: Thirty male Wistar rats were used in the study. A ligature was placed around one of the mandible first molars (ligated teeth) of each animal, and they were then randomly assigned to one of two groups: control (n = 15) or marijuana smoke inhalation ([MSI] for 8 minutes per day; n = 15). Urine samples were obtained to detect the presence of tetrahydrocannabinol. After 30 days, the animals were sacrificed and decalcified sections of the furcation area were obtained and evaluated according to the following histometric parameters: bone area (BA), bone density (BD), and BL. Results: Tetrahydrocannabinol was positive in urine samples only for the rats of the MSI group. Non‐significant differences were observed for unligated teeth from both groups regarding BL, BA, and BD (P >0.05). However, intragroup analysis showed that all ligated teeth presented BL and a lower BA and BD compared to unligated teeth (P <0.05). The intergroup evaluation of the ligated teeth showed that the MSI group presented higher BL and lower BD (P <0.05) compared to ligated teeth from the control group. Conclusion: Considering the limitations of this animal study, cannabis smoke may impact alveolar bone by increasing BL resulting from ligature‐induced periodontitis.     

显微计算机辅助断层摄影技术在牙周病学中的应用

显微计算机辅助断层摄影技术(micro-CT)是一种高分辨率的三维重建影像技术,其快速准确的影像特点使其在牙周疾病的诊断、预后判定及相关基础研究中具有广泛的应用潜能,并有望提高牙周疾病的诊疗水平及预后判断.本文就micro-CT的工作原理及其在牙周疾病中的应用作一综述.     

Economic perspectives on diagnosis and treatment planning in periodontology

Abstract Economic factors in diagnosis and treatment planning in periodontology may be considered from several points of view. A first perspective is that of government responsibility. Because of the explosion in health care expenditure in the last decade, public funding of dental care programmes may become static or even reduced. Most governments try to curb the ever growing public health expenditure. Consequently, terms like effectiveness, efficiency and accountability are now becoming common words also in relation to periodontal health care. Moreover, private insurance companies, which have entered this area, may be individual patient who, explicitly or implicitly, would like to consider the services individual patient, who explicitly or implicitly, would like to consider the sendees rendered in periodontal therapy and prevention as cost-effective. Features of supply of and demand for care on an individual basis should also be considered. Finally, the periodontist or general practitioner has to consider economic factors. In professional life, there should be a balance between good working conditions providing satisfactory care, and the demands and priorities of individual patients and the community at large.     

Periodontal conditions in adolescents, 15–19 years of age: an overview ot CPITN data in the WHO Global Oral Data Bank

Results of 61 CPITN surveys in 39 countries for the age group 15-19 yr, stored in the WHO Global Oral Data Bank as of 1 July 1987, are assembled in an overview showing percentages of persons according to the highest score for each person and the mean numbers of sextants affected per person. The most frequently observed condition was score 2 (calculus with or without bleeding), although some shallow pocketing of 4 or 5 mm was present in most populations surveyed. It should thus be emphasized that the major thrust of activities in periodontal care should be in health promotion and education, leading to improved oral hygiene.     

Associations of serum concentrations of IgG,IgA, IgM and interleukin-1beta with early-onset periodontitis classification and race

BACKGROUND: The significance of serum concentrations of various antibodies and cytokines in the pathogenesis of early-onset periodontitis (EOP) is not well understood. Recent reports suggest differences between young blacks and whites in certain humoral responses, regardless of periodontal status. This study was undertaken to compare the serum concentrations of IgG, IgA, IgM, and IL-1beta in EOP subjects with that of healthy controls, and to study the effect of race on these levels. MATERIAL AND METHODS: This case-control study included 228 individuals, 19-25 years old who were selected from a larger population examined in the National Survey of Oral Health of United States Children in 1986/1987. The subjects were classified by their EOP status and they included 166 subjects with EOP and 62 healthy controls. Blood samples were used to assess the serum concentrations of IgG, IgM, IgA, IgG subclass, and IL-1beta. RESULTS: The serum concentrations of IgG, IgG subclasses, IgA, and IgM in blacks were not significantly different in the generalized, localized and incidental EOP groups as compared to the healthy controls. The serum IL-1beta concentration was slightly and uniformly lower in the EOP groups than in the control group, although not statistically significant. Blacks had significantly higher serum concentrations of total IgG, and of IgG1, IgG2 and IgG3 than whites and Hispanics. Hispanics had significantly higher serum concentrations of IgM and IgG4 than whites and blacks. Hispanics also had a significantly higher serum concentration of IL-1beta than blacks. CONCLUSIONS: Total antibody response in blacks is not associated with EOP classification. Race has a significant effect on serum antibody concentrations irrespective of disease classification, with blacks having significantly higher serum concentrations of IgG1, IgG2 and IgG3 than whites and Hispanics.     

Reconstructive periodontal surgery: A challenge for modern periodontology

The overall rationale for the proposed clinical approach in this paper comes from consideration of different regenerative approaches reported in the literature. The protocol proposed is based mainly on evidence and partly on the clinical experience of the author and co‐workers, who have found that patient associated factors such as plaque control, residual periodontal infection, and smoking habits are those of particular relevance. Among the technical/surgical associated factors, lack of primary closure of the interdental space and consequent bacterial contamination of the regenerating wound represent the most significant factors leading to compromised outcomes. Modified flap designs and a micro‐surgical approach have been shown to improve the outcomes. There is now sufficient evidence to suggest that clinicians can incorporate periodontal regeneration in their surgical armamentarium. Periodontal regeneration can be predictably used to treat deep pockets associated with deep intrabony defects in young and old people, aimed at pocket/defect resolution with aesthetic preservation, gain of clinical attachment and bone.     

Host responses induced by different animal models of periodontal disease: a literature review

Periodontitis is an infectious disease characterized by chronic inflammation of the periodontium, and it is mediated and modulated by the host immune system. In the presence of microorganisms or other antigens, immune cells (macrophages/monocytes, dendritic cells, lymphocytes, neutrophils), endothelial cells and fibroblasts secrete cytokines and trigger immune and inflammatory reactions. However, when synthesized at high levels, cytokines modify the pattern of cellular response, participating substantially in the development of chronic inflammatory pathologies, such as periodontal disease. Understanding the origin and progression of bone resorption is one of the primary goals of the field of periodontics, aiming to arrest the disease progression and to optimize future treatments. For this purpose, the development of experimental models is an important and necessary step before entering into clinical trials with new therapies. The purpose of this study is to characterize/evaluate the tissue changes induced by various models of experimental periodontitis through a literature review.     

颌骨放射性骨坏死动物模型的研究进展

颌骨放射性骨坏死（osteoradionecrosis of jaws,ORNJ）是头颈部肿瘤放疗后最严重的并发症之一。该疾病进展慢,病程长,发病机制尚未完全明确。由于缺乏有效的治疗措施,临床处理较为棘手。ORNJ动物模型对于研究该疾病的发病机制、预防及治疗均有重要意义。现就ORNJ动物建模在动物选择,建模方案,评估指标及模型应用等方面进行综述。     

Occurrence of Spontaneous Periodontal Disease in the SAMP1/YitFc Murine Model of Crohn Disease

Background: Oral involvement is often associated with inflammatory bowel disease (IBD). Recent evidence suggests a high incidence of periodontal disease in patients with Crohn disease (CD). To the best of the authors’ knowledge, no animal model of IBD that displays associated periodontal disease was reported previously. The aim of this study is to investigate the occurrence and progression of periodontal disease in SAMP1/YitFc (SAMP) mice that spontaneously develop a CD‐like ileitis. In addition, the temporal correlation between the onset and progression of periodontal disease and the onset of ileitis in SAMP mice was studied. Methods: At different time points, SAMP and parental AKR/J (AKR) control mice were sacrificed, and mandibles were prepared for stereomicroscopy and histology. Terminal ilea were collected for histologic assessment of inflammation score. Periodontal status, i.e., alveolar bone loss (ABL) and alveolar bone crest, was examined by stereomicroscopy and histomorphometry, respectively. Results: ABL increased in both strains with age. SAMP mice showed greater ABL compared with AKR mice by 12 weeks of age, with maximal differences observed at 27 weeks of age. AKR control mice did not show the same severity of periodontal disease. Interestingly, a strong positive correlation was found between ileitis severity and ABL in SAMP mice, independent of age. Conclusions: The present results demonstrate the occurrence of periodontal disease in a mouse model of progressive CD‐like ileitis. In addition, the severity of periodontitis strongly correlated with the severity of ileitis, independent of age, suggesting that common pathogenic mechanisms, such as abnormal immune response and dysbiosis, may be shared between these two phenotypes.     

Effects of Probiotic Therapy on Metabolic and Inflammatory Parameters of Rats With Ligature‐Induced Periodontitis Associated With Restraint Stress

Background: This study evaluates the effects of probiotic therapy (PT) in rats with ligature‐induced periodontitis associated with restraint stress. Methods: Sixty‐four rats were divided into control, stress (STR), probiotic (PROB), periodontal disease (PD), STR‐PROB, STR‐PD, STR‐PROB‐PD, and PROB‐PD groups. The probiotic was added to the drinking water for 44 days. PD was induced by a ligature. In STR groups, the animals were subjected to restraint stress for 2.5 hours per day for 30 days. Results: Rats with PD exhibited increased alveolar bone loss (P <0.05), as well as increased levels of cyclooxygenase‐2, serum C‐terminal telopeptide (CTX), p38 mitogen‐activated protein kinase (p38), and receptor activator of nuclear factor‐κB ligand and decreased levels of osteoprotegerin (OPG). Stressed rats presented high levels of C‐peptide, corticosterone, and glucose (P <0.05). In general, the presence of stress reduced the expression of CTX and p38 (P <0.05). PT reduced alveolar bone loss in unstressed animals. It also decreased expression of CTX and induced increased expression of OPG in unstressed animals with PD. However, PT was not effective in preventing bone loss or altering the expression of inflammatory markers in stressed animals. PT decreased the number of inflammatory cells in the periodontal tissue (P <0.05). Groups with stress and PD showed decreased villous height and crypt depth. Stress seemed to prevent part of the probiotic beneficial effects on the small intestine. Conclusions: Based on the methodology used, PT may reduce tissue breakdown resulting from PD in unstressed rats. The protocol used for restraint stress influenced the immunomodulatory effects of PT in intestinal and periodontal tissues.     

Accelerated alveolar bone loss in male HLA-B27 transgenic rats: adult onset

OBJECTIVE AND BACKGROUND: HLA-B27 transgenic (TG) rats exhibit severe colitis, arthritis and other inflammatory lesions. Previous studies in female TG rats indicate that they develop severe alveolar bone loss (ABL). Lack of data on male TG rats has left open the question of possible hormonal/sex dependence for the observed ABL. The purpose of the present study was to assess the natural history of ABL in male HLA-B27 rats, compared to age- and sex-matched wild-type Fischer 344 (WT) rats. MATERIALS AND METHODS: Fourteen WT and 11 TG male rats, aged 7-8 weeks, were used. Sacrifice times occurred at 10, 22 and 35 weeks. Animal heads were defleshed and treated to remove organic material, and skulls were stained to locate the cemento-enamel junction. ABL was measured as exposed molar root surface area (mm2) on the right maxilla and right mandible. Blinded measurements were performed using a computer-assisted image analysis system. RESULTS: ABL for the entire TG group was significantly different from the WT group (p < 0.05). There was no significant difference in ABL between WT and TG rats at 10 weeks of age. At 22 and 35 weeks of age TG rats experienced 23% and 37% greater ABL than WT rats, respectively; these differences were statistically significant (p < 0.015). For both TG and WT animals, ABL was significantly different between the three age groups. CONCLUSIONS: These results, consistent with previous findings in female TG rats, suggest that the accelerated ABL found in TG rats is an adult-onset, age-dependent, and sex-independent process.     

Oral bacteria and respiratory infection: effects on respiratory pathogen adhesion and epithelial cell proinflammatory cytokine production

Several microbiologic and epidemiologic studies have suggested an association between dental plaque, poor oral health, and respiratory diseases such as nosocomial pneumonia and chronic obstructive pulmonary disease (COPD). A number of hypotheses are suggested to help explain how oral bacteria may participate in the pathogenesis of respiratory infection. Resident bacteria in oral secretions are likely aspirated along with respiratory pathogens and may affect the adhesion of the later organisms to the respiratory epithelium. Preliminary studies performed in our laboratory suggest that oral bacteria may modulate the adhesion of respiratory pathogens to epithelial cell lines. In addition, oral bacterial products or cytokines in oral/pharyngeal aspirates may stimulate cytokine production from respiratory epithelial cells, resulting in recruitment of inflammatory cells. The resulting inflamed epithelium may be more susceptible to respiratory infection. Further preliminary data are presented that some species of oral bacteria may induce the release of proinflammatory cytokines from epithelial cell lines to an extent similar to that seen for respiratory pathogens.     

Periodontal conditions in 35–44-year-old factory workers in Shanghai

Abstract A periodontal survey applying CPITN was carried out in almost 500 male and female factory workers, 35–44 yr of age, in Shanghai, P.R. China. Calculus and shallow pockets were most frequent. Deep pockets of 6 mm and over were seldom found. The mean number of missing teeth was only 2.7 (out of 32). Problems associated with third molars seem to provide the largest immediate oral health problem     

Supportive care after active periodontal treatment

Abstract This review concerns the most significant questions regarding supportive (maintenance) care after active periodontal treatment: the effectiveness and ideal frequency of maintenance appointments, the adecuacy of the supportive therapy according to patient needs, the possible alternatives to currently accepted protocols, and the relative value of personal oral hygiene in the overall context of supportive care. Periodontal diseases are infections with a high potential for recurrence, progressive loss of attachment and eventually, tooth loss. Current therapies for periodontal diseases are highly predictable in arresting disease activity. Supportive periodontal care has been shown to be very effective in maintaining support when adapted to each particular case. Nevertheless, current maintenance therapies may be unsuccessful in preventing further loss of attachment in a small number of sites for some patients. Tests aiming at bacterial identification and the subgingival application of antimicrobials may be helpful in the management of such cases, however the practical value in a specific setting is not known. There is growing evidence of the fundamental role of personal oral hygiene in supportive periodontal care. In cases with rapid and severe periodontal destruction and where local and/or systemic risk factors are present, personal oral hygiene becomes a key factor in the long-term preservation of periodontal support.     

Statistical models for data from periodontal research

Many factors have been hypothesised either to characterise groups and individuals at risk for periodontal disease or to be markers of periodontal breakdown. In order to identify these as associated either with disease status or progression, a statistical association between the factor and a measure of disease will have to be demonstrated. The statistical modelling of data arising from periodontal research presents special problems. These include the large number of measurements made in each subject, the large magnitude of measurement error compared to the changes in attachment level, the analysis of longitudinal studies, the lack of a measure of instantaneous rate of attachment loss and controversies over the nature of the progression of the disease. We consider statistical methods currently available in the light of these difficulties and identify areas in which further research is necessary.     

�ҹ����ܲ�����������˼��

牙周病是目前人类最常见和高发的慢性感染性疾病,没有一个国家、地区、种族、性别、年龄的人群可以幸免,可以说每个人都处于罹患牙周病的危险之中,只是患病率和严重程度有所差异而已。目前已经公认,牙周病对口腔健