Bernd-Michael Kleber

Bio: Bernd-Michael Kleber is an academic researcher from Charité. The author has contributed to research in topics: Aggressive periodontitis & Periodontitis. The author has an hindex of 14, co-authored 17 publications receiving 1180 citations.

Obesity, Inflammation, and Periodontal Disease

Abstract: The prevalence of obesity has increased substantially over the past decades in most industrialized countries. Obesity is a systemic disease that predisposes to a variety of co-morbidities and complications that affect overall health. Cross-sectional studies suggest that obesity is also associated with oral diseases, particularly periodontal disease, and prospective studies suggest that periodontitis may be related to cardiovascular disease. The possible causal relationship between obesity and periodontitis and potential underlying biological mechanisms remain to be established; however, the adipose tissue actively secretes a variety of cytokines and hormones that are involved in inflammatory processes, pointing toward similar pathways involved in the pathophysiology of obesity, periodontitis, and related inflammatory diseases. We provide an overview of the definition and assessment of obesity and of related chronic diseases and complications that may be important in the periodontist's office. Studies that have examined the association between obesity and periodontitis are reviewed, and adipose-tissue-derived hormones and cytokines that are involved in inflammatory processes and their relationship to periodontitis are discussed. Our aim is to raise the periodontist's awareness when treating obese individuals.

Association Among Rheumatoid Arthritis, Oral Hygiene, and Periodontitis

Abstract: Background: A limited number of studies suggest a higher prevalence of periodontal disease among individuals with rheumatoid arthritis (RA); however, results have been inconsistent. Further, it is unclear to what extent poor oral hygiene among patients with RA may account for this association.Methods: The association between RA and periodontitis was examined in 57 subjects with RA and 52 healthy controls, matched by age and gender. Oral examination included plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment loss (CAL). Potential risk factors for periodontal disease, such as smoking, education, alcohol consumption, and body mass index (BMI), as well as chronic diseases associated with RA and periodontal disease were assessed through questionnaires.Results: In a stepwise logistic regression, including RA status, age, gender, education, smoking, alcohol consumption, and BMI, only RA status and age remained significant predictors of periodontal disease. Subjects with RA had a ...

Ridge augmentation and maxillary sinus grafting with a biphasic calcium phosphate: histologic and histomorphometric observations.

Abstract: OBJECTIVES: This retrospective study reports on histologic and histomorphometric observations performed on human biopsies harvested from sites augmented exclusively by biphasic calcium phosphate [BCP: hydroxyapatite (HA)/ tricalcium phosphate (TCP) 60/40] and healed for a minimum of 6 months. MATERIALS AND METHODS: Five patients benefited from three augmentation regimens (i.e.: one-stage lateral augmentation; two-stage lateral augmentation; and two-stage sinus grafting). In all patients, a degradable collagen membrane served as a cell-occlusive barrier. Core biopsies were obtained from lateral as from crestal aspects 6-10 months after augmentation surgeries. For histologic and histomorphometric evaluations, the non-decalcified tissue processing was performed. RESULTS: The histological examination of 11 biopsies showed graft particles frequently being bridged by the new bone, and a close contact between the graft particles and newly formed bone was seen in all samples. The mean percentages of newly formed bone, soft tissue compartment, and graft material were 38.8% (+/-5.89%), 41.75% (+/-6.08%), and 19.63% (+/-4.85%), respectively. Regarding bone-to-graft contact values, the percentage of bone coverage of graft particles for all biopsies ranged from 27.83% to 80.17%. The mean percentage of bone coverage was 55.39% (+/-13.03%). CONCLUSIONS: Data from the present study demonstrated osteoconductivity scores for the BCP material (HA/TCP 60/40) in patients resembling those previously shown for grafting materials of xenogenic and alloplastic origin.

Timing Affects the Clinical Outcome of Adjunctive Systemic Antibiotic Therapy for Generalized Aggressive Periodontitis

Abstract: Background: Systemic antibiotics improve the outcome of scaling and root planing (SRP) in patients exhibiting severe periodontitis. This study evaluated the influence of timing of adjunctive systemic antibiotics in the sequence of periodontal therapy. Methods: Two cohorts of patients with generalized aggressive periodontitis and treated by SRP, adjunctive antibiotics, and supportive periodontal therapy (SPT) were analyzed retrospectively. Cohort A (17 patients; 36 – 5 years of age) received systemic amoxicillin/metronidazole immediately after SRP (‘‘immediate’’); cohort B (17 patients; 36 – 4 years of age) received the same regimen 3 months after SRP, following SPT, including subgingival reinstrumentation (‘‘late’’). Clinical parameters, including probing depth (PD), relative attachment level (RAL), bleeding on probing (BOP), and suppuration, were recorded with a pressure-sensitive electronic probe at baseline and 3 and 6 months after SRP. Results: Significant time*group interactions were found for all clinical parameters except BOP, i.e., timing of antibiotic therapy affected the course of clinical changes over time. Immediate antibiotic therapy produced significantly higher initial changes (0 to 3 months) in PD and RAL. Late antibiotic therapy at 3 months resulted in additional significant improvements in all clinical parameters between 3 and 6 months. In initially deep sites (baseline PD >6 mm), improvements in PD and RAL over 6 months were significantly higher with immediate antibiotic therapy compared to late antibiotic therapy. Conclusion: Within the limits of a retrospective analysis, these findings indicate that administration of amoxicillin/ metronidazole immediately after initial SRP provides more PD reduction and RAL ‘‘gain’’ in initially deep sites than late administration at SPT with reinstrumentation after 3 months. J Periodontol 2007;78:1201-1208.

Gingival crevicular fluid levels of calprotectin and myeloperoxidase during therapy for generalized aggressive periodontitis.

Abstract: Background: Levels of the inflammation marker calprotectin in gingival crevicular fluid correspond to clinical and biochemical parameters of periodontal inflammation. Neutrophil granulocytes (polymorphonuclear neutrophils: PMNs) are supposed to be the main source of calprotectin in gingival crevicular fluid, but evidence is still lacking. The influence of periodontal therapy on gingival crevicular fluid levels of calprotectin has not yet been determined. Objectives: Gingival crevicular fluid levels of calprotectin were monitored during therapy for generalized aggressive periodontitis. Interrelations between calprotectin and the PMN marker myeloperoxidase (MPO) were evaluated. Material and methods: Gingival crevicular fluid samples were collected from 23 patients with generalized aggressive periodontitis before and 3 months after non-surgical therapy with an adjunctive antimicrobial medication. Clinical parameters were recorded with a pressure-calibrated electronic probe. Levels of calprotectin and MPO in gingival crevicular fluid were analysed by enzyme-linked immunosorbent assay (ELISA) procedures. Results: At baseline, levels of calprotectin and MPO were highly correlated. Bleeding and suppurating sites showed significantly higher levels of calprotectin and MPO than non-bleeding, non-suppurating sites. Therapy significantly decreased levels of both biomarkers. These changes of calprotectin and MPO were highly correlated and also related to probing-depth reduction. Three months after therapy, the levels of both markers still showed significant correlations in initially deep sites, whereas in initially shallow sites no significant correlation was found. After therapy, levels of markers in bleeding and non-bleeding sites were comparable. Conclusion: The correlations between calprotectin and MPO indicate that PMNs are a major contributor to the calprotectin content in gingival crevicular fluid of severely affected sites. Calprotectin levels in gingival crevicular fluid and their changes reflect periodontal inflammation as well as the clinical treatment outcome. A prognostic potential of this marker substance remains to be determined.

Periodontitis and diabetes: a two-way relationship

Abstract: Periodontitis is a common chronic inflammatory disease characterised by destruction of the supporting structures of the teeth (the periodontal ligament and alveolar bone). It is highly prevalent (severe periodontitis affects 10–15% of adults) and has multiple negative impacts on quality of life. Epidemiological data confirm that diabetes is a major risk factor for periodontitis; susceptibility to periodontitis is increased by approximately threefold in people with diabetes. There is a clear relationship between degree of hyperglycaemia and severity of periodontitis. The mechanisms that underpin the links between these two conditions are not completely understood, but involve aspects of immune functioning, neutrophil activity, and cytokine biology. There is emerging evidence to support the existence of a two-way relationship between diabetes and periodontitis, with diabetes increasing the risk for periodontitis, and periodontal inflammation negatively affecting glycaemic control. Incidences of macroalbuminuria and end-stage renal disease are increased twofold and threefold, respectively, in diabetic individuals who also have severe periodontitis compared to diabetic individuals without severe periodontitis. Furthermore, the risk of cardiorenal mortality (ischaemic heart disease and diabetic nephropathy combined) is three times higher in diabetic people with severe periodontitis than in diabetic people without severe periodontitis. Treatment of periodontitis is associated with HbA1c reductions of approximately 0.4%. Oral and periodontal health should be promoted as integral components of diabetes management.

The role of the gut microbiota in energy metabolism and metabolic disease.

Abstract: Obesity is now classically characterized by a cluster of several metabolic disorders, and by a low grade inflammation. The evidence that the gut microbiota composition can be different between healthy and or obese and type 2 diabetic patients has led to the study of this environmental factor as a key link between the pathophysiology of metabolic diseases and the gut microbiota. Several mechanisms are proposed linking events occurring in the colon and the regulation of energy metabolism, such as i.e. the energy harvest from the diet, the synthesis of gut peptides involved in energy homeostasis (GLP-1, PYY...), and the regulation of fat storage. Moreover, the development of obesity and metabolic disorders following a high-fat diet may be associated to the innate immune system. Indeed, high-fat diet feeding triggers the development of obesity, inflammation, insulin resistance, type 2 diabetes and atherosclerosis by mechanisms dependent of the LPS and/or the fatty acids activation of the CD14/TLR4 receptor complex. Importantly, fat feeding is also associated with the development of metabolic endotoxemia in human subjects and participates in the low-grade inflammation, a mechanism associated with the development of atherogenic markers. Finally, data obtained in experimental models and human subjects are in favour of the fact that changing the gut microbiota (with prebiotics and/or probiotics) may participate in the control of the development of metabolic diseases associated with obesity. Thus, it would be useful to find specific strategies for modifying gut microbiota to impact on the occurrence of metabolic diseases.

The rationale for targeting the LOX family in cancer.

Abstract: The therapeutic targeting of extracellular proteins is becoming hugely attractive in light of evidence implicating the tumour microenvironment as pivotal in all aspects of tumour initiation and progression. Members of the lysyl oxidase (LOX) family of proteins are secreted by tumours and are the subject of much effort to understand their roles in cancer. In this Review we discuss the roles of members of this family in the remodelling of the tumour microenvironment and their paradoxical roles in tumorigenesis and metastasis. We also discuss how targeting this family of proteins might lead to a new avenue of cancer therapeutics.