Aubrey Soskolne

New sustained release dosage form of chlorhexidine for dental use. II. Use in periodontal therapy.

This study was carried out to examine the release kinetics of chlorhexidine from a sustained release device (S. R. D.) prepared from ethyl cellulose (fast S. R. D.) or ethyl cellulose with polyethylene glycol (slow S. R. D.) and to examine the effects on the bacterial flora of pockets in patients with periodontal disease. It was shown that fast S. R. D.s release up to 80% of the chlorhexidine within the first 3 days in insertion in periodontal pockets, whereas the slow S. R. D.s release 50% of the chlorhexidine content after 6 days. The release kinetics of chlorhexidine from S. R. D.s placed in pockets as expressed by the Higuchi system (Higuchi 1963) indicate that it is diffusion controlled. The rate of chlorhexidine release is dependent on the structure of S. R. D., the drag concentration within the device, and the effective surface area. The microbial flora of sixteen pockets from 6 patients were examined using darkfield microscopy at day 0, 3, 10, and 14 after treatment with S. R. D.s containing, chlorhexidine or placebo S. R. D.s. The pocket depths ranged from 5–8 mm. The chlorhexidine-treated group showed a marked decrease in the relative proportions of motile rods and spirochetes and a corresponding increase in non-motile organisms compared to the flora prior to chlorhexidine treatment or compared to the flora of the placebo treated pockets. These differences were significant up to 10 days post treatment (P < 0.0025). The study indicated the effectiveness of ethyl cellulose polymers as S. R. D.s in vivo and their ability to reduce the relative proportions of the motile organisms of periodontal pockets to negligible amounts.

Sustained release device containing minocycline for local treatment of periodontal disease

Abstract This study reports the development of a system for the sustained release of minocycline for use in the treatment of periodontal diseases. Films of ethylcellulose containing 30% (w/w) minocycline cast from ethanol, chloroform, or chloroform with polyethylene glycol were prepared as sustained release delivery devices. The release rate and the antibacterial activity of minocycline were measured in vitro and in vivo. The results indicate that each formulation studied releases the minocycline at a rate that decreases with time. The release kinetics of minocycline in vivo correlate with the in vitro results. The results of the short-term clinical study indicate that use of the device in periodontal pockets may cause complete eradication of the pathogenic bacteria from the pocket.

Oral Lichen Planus and Dental Implants – A Retrospective Study

OBJECTIVES To examine whether oral lichen planus (OLP) affects the success rate of dental implants and if the manifestations of OLP are altered by implant-borne prostheses. MATERIALS AND METHODS OLP patients, treated in the oral medicine department, with (the study group) and without (control group) dental implants were included. Pocket depth, mobility, bleeding on probing, erythema, pain and radiolucency around the implants, as well as clinical findings and OLP symptoms were recorded. Follow-up ranged from 12-24 months. Ordinal variables and visual analog scale score were compared using the Mann-Whitney test. The significance of the trend within each of the groups was assed using the Friedman test. Categorical variables were compared using Pearson chi-squared test and Fishers exact test. RESULTS Fourteen patients in the study group with 1-15 implants per patient and 15 in the control group were included. No implant failures were recorded. Comparison between the clinical manifestations of OLP in both groups did not reveal any significant differences. CONCLUSIONS Success of implant rehabilitation among treated OLP patients does not seem to be different from the success rate in the general population. Nor does implant placement influence the disease manifestations.Objectives: To examine whether oral lichen planus (OLP) affects the success rate of dental implants and if the manifestations of OLP are altered by implant-borne prostheses. Materials and Methods: OLP patients, treated in the oral medicine department, with (the study group) and without (control group) dental implants were included. Pocket depth, mobility, bleeding on probing, erythema, pain and radiolucency around the implants, as well as clinical findings and OLP symptoms were recorded. Follow-up ranged from 12–24 months. Ordinal variables and visual analog scale score were compared using the Mann–Whitney test. The significance of the trend within each of the groups was assed using the Friedman test. Categorical variables were compared using Pearson chi-squared test and Fishers exact test. Results: Fourteen patients in the study group with 1–15 implants per patient and 15 in the control group were included. No implant failures were recorded. Comparison between the clinical manifestations of OLP in both groups did not reveal any significant differences. Conclusions: Success of implant rehabilitation among treated OLP patients does not seem to be different from the success rate in the general population. Nor does implant placement influence the disease manifestations.

Induction of tumor necrosis factor α and interleukin-1β in subcutaneously implanted chamber by lipopolysaccharide

Lipopolysaccharide (LPS) is the major component of the outermost membrane of Gram-negative bacteria and is considered to be one of the major virulence factors of these bacteria. While the effect of systemic injection of LPS is well characterized, the characterization of cytokine secretion in response to local injection of LPS is lacking. The present study was designed to determine the local production of tumor necrosis factor α (TNFα) and interleukin-1β (IL-1β) over a 4 day period following injection of LPS into subcutaneous implanted chambers in mice. Mice were challenged by a single or repeated injection of Salmonella typhosa LPS into the chambers. Chamber fluids were aspirated at different time intervals and were used for assessment of leukocyte and cytokine levels. A single injection of LPS was found to induce cell influx into the chamber which peaked after 4 h. TNFα and IL-1β levels increased rapidly, reaching their maximum levels within 4 h. After 24 h, TNFα levels declined markedly and were undetectable at 48 and 96 h. TNFα mRNA levels in the sedimented cells followed a similar pattern. In contrast, IL-1β showed a more gradual decrease with levels significantly different from baseline still being present 96 h post-LPS challenge. Four consecutive daily injections of LPS into the chambers resulted in undetectable levels of TNFα in the chamber fluid, while significant levels of IL-1β were detected. These levels were significantly higher than the levels of IL-1β in the chamber fluid 96 h after a single injection and approximately 60% of the levels measured 24 h after a single intra-chamber injection of LPS. The results emphasize the difference between single and repeated exposure to LPS in vivo, and suggest a role for TNFα in the initial phase of the local inflammatory response and for IL-1β in the later phase.