Physical key properties of antibiotic-free, PLGA/HPMC-based in-situ forming implants for local periodontitis treatment.

In-situ forming implants (ISFI) offer an interesting potential for the treatment of periodontitis, allowing for time-controlled drug release directly at the site of action (which is difficult to reach). For this purpose, ISFI loaded with antibiotics have been reported in the literature. But the use of antibiotic drugs at low doses over prolonged periods of time can lead to the development of bacterial resistances. This risk should be avoided. The aim of this study was to develop a novel type of in-situ forming implants, loaded with the antiseptic drug chlorhexidine. Special emphasis was placed on the physical properties of the systems, assuring a reliable residence time in the periodontal pockets of patients suffering from periodontitis. In particular, the risk of premature, accidental loss of the formulations due to mechanical stress (e.g. during tooth brushing and chewing) was to be reduced. Two commercially available drug products for local periodontitis treatment were studied for reasons of comparison: Chlo-site and Parocline. The syringeability and swelling behavior of the formulations were investigated, and the hardness, springiness, resilience and "stickiness" of the systems determined using extracted human teeth. Interestingly, the novel in-situ forming implants, based on PLGA/HPMC and being free of antibiotics, exhibit highly promising physical key properties: They are intensively sticking to teeth' surfaces and provide adequate mechanical strength to assure reliable and prolonged residence times in periodontal pockets. In contrast, the commercial drug products showed limited adhesion and either rapidly shrank (Chlo-site), or substantially swelled and were mechanically very weak (Parocline).

Periodontal manifestations of inflammatory bowel disease: emerging epidemiologic and biologic evidence.

Inflammatory bowel disease and periodontitis are both described as a disproportionate mucosal inflammatory response to a microbial environment in susceptible patients. Moreover, these two conditions share major environmental and lifestyle-related risk factors. Despite this intriguing pathogenic parallel, large-scale studies and basic research have only recently considered periodontal outcomes as relevant data. There are mounting and consistent arguments, from recent epidemiologic studies and animal models, that these two conditions might be related. This article is a comprehensive and critical up-to-date review of the current evidence and future prospects in understanding the biologic and epidemiologic relationships between periodontal status and inflammatory bowel disease.

Functionalization of PVDF membranes with carbohydrate derivates for the controlled delivery of chlorhexidin.

Maltodextrin (MX) was fixed onto PVDF membranes in order to create a drug delivery Guided Tissue Regeneration (GTR) device with controlled drug delivery properties. PVDF microporous membranes were treated by a mixture of MX and citric acid, resulting to an 18 wt% increase of the supports. MX grafted membrane could capture 103 mg/g chlorhexidin digluconate (DigCHX) instead of 1mg/g for a virgin membrane. A neutralization step was performed before the biological tests. Viability tests confirmed the non-toxicity of the MX polymer coating after neutralisation. In vitro release test in human plasma, and microbiological tests showed that membranes grafted with MX were more performing compared to virgin and beta-CD grafted membranes. The antimicrobial activity was effective during more than 72 h.

Improved drug delivery properties of PVDF membranes functionalized with beta-cyclodextrin--application to guided tissue regeneration in periodontology.

The purpose of this study was to develop a membrane for guided tissue regeneration applicable in periodontology that could release antimicrobial agent during the healing period. Our strategy consisted to graft beta-cyclodextrin (beta-CD), a molecule that is known to form inclusion complexes with a large variety of drugs, onto PVDF membranes. Grafting occurred by using citric acid that provoked a crosslinking reaction of beta-CD, and the resulting polymer was imprisoned into the porous structure of the PVDF membrane. The reaction produced a weight increase of the membrane, the range of which depended on the temperature and on the time of curing applied in the process. The biological behavior of the membranes evaluated by proliferation and vitality tests showed good proliferation and improved activity of L132 epithelial cells on the raw and on the grafted membranes. Doxycyclin (DOX) and chlorhexidine (CHX) were used as antimicrobial agents. Their inclusion into the beta-CD cavity in aqueous solutions was confirmed by NMR spectroscopy. After the impregnation of the membranes with DOX and CHX, their release was studied in vitro in batch type experiments and measured by UV spectrophotometry. Low amounts of DOX and CHX were delivered from the raw membranes within the first few hours of tests. Grafted membranes, however, delivered DOX and CHX in larger quantities within 24 h and 10 days respectively.

[Periodontal diseases, tobacco and pregnancy]. / Maladies parodontales, tabac et grossesse.

This review summarizes the impact of tobacco on the periodontium of pregnant women and the effects of periodontal diseases combined with tobacco on the pregnancy. Periodontal diseases (gingivitis and periodontitis) are gram-negative anaerobic infections. Smokers are 2-7 times more likely to develop periodontal disease than non-smokers. Tobacco, an environmental factor, undermines the host response and may facilitate the development and progression of periodontal disease. Recent epidemiological studies suggest that maternal periodontal diseases would be a risk factor of pre-term deliveries or pre-term low birth weight (PLBW). Cigarette smoking during pregnancy leads to peri-natal morbidity and mortality and it is associated with reduced birth-weight. Tobacco during pregnancy also amplifies the risk of PLBW directly and via periodontal diseases. This article highlights the etio-pathogenic interrelations between periodontal diseases and tobacco as risk factors of PLBW. The blood dissemination of periodontal bacteria and the effects of cytokines like TNF-alpha, Il-1, produced during periodontal infections could explain these obstetrical adverse events. The concept of diagnosing and treating a periodontal disease in a pregnant woman to minimizes the deleterious effects of this infection on systemic conditions represents an unprecedented challenge. Moreover, periodontist have the opportunity to take part in smoking cessation program for pregnant women.

Features of severe periodontal disease in a teenager with Chédiak-Higashi syndrome.

BACKGROUND: Chédiak-Higashi syndrome (C-HS) is a rare congenital disease characterized by defective neutrophil function with abnormal lysosomal inclusions, neutropenia, and reduced chemotaxis. The complete syndrome includes oculocutaneous albinism with photophobia, neurologic features, recurrent infections, and enterocolitis. METHODS: A 14-year-old male C-HS patient was referred to us because of serious periodontal destruction with acute inflamed gingiva and ulcers. Clinical and biological investigations were performed, leading to the diagnosis of C-HS. RESULTS: Laboratory findings included neutropenia and hypergammaglobulinemia. Peripheral blood smears showed giant granules in neutrophils, eosinophils, and granulocytes. Bone marrow smears showed giant inclusions in leukocyte precursor cells. These granules and inclusions were characteristic of Chédiak-Higashi syndrome. Oral radiographic status showed extensive loss of alveolar bone leading, in most cases, to tooth exfoliation. Bacteria often associated with periodontitis were detected in subgingival plaque samples, including Fusobacterium nucleatum, Campylobacter rectus, Prevotella melaninogenica, Peptostreptococcus anaerobius, and Clostridium sp. Biopsies of periodontal tissues for light and electronic microscopic examinations revealed massive bacterial invasion of the epithelial tissue, epithelial cells, and connective tissue. Ultrastructural observations of periodontal polymorphonuclear leukocytes showed defective granulation, with abnormal granules not discharging their lysosomal content against engulfed bacteria. Viable dividing bacteria were found in the cytoplasm. CONCLUSIONS: In this case, early-onset periodontitis seems to be the expression of C-HS granulocyte deficiency. Periodontal treatment of these patients is often unsuccessful. This case report illustrates the importance of the dentist in initiating clinical and biological investigations in such early aggressive periodontitis in young patients.