An 8-week, randomized, controlled, clinical study of the use of a 0.1% chlorhexidine mouthwash by chronic periodontitis patients.

AIM: To evaluate the efficacy of a 2-week administration of a 0.1% chlorhexidine mouthwash in the short-term treatment of chronic periodontitis patients and the impact of this product when administered twice by pocket irrigation. METHODS: Sixty patients were enrolled in a single-centre, placebo-controlled, randomized study with the blind allocation of product to two parallel groups. Clinical assessments were performed, and samples from six selected subgingival sites were collected for microbial analysis by culture at baseline, D15 and D56. Three of the six sites were randomly selected and were treated by subgingival irrigation with the same 0.1% chlorhexidine product at D0 and D7. A subsequent statistical analysis was performed using the paired Student's t-test and Wilcoxon rank sum test for within-group analyses; analysis of variance and the Kruskall-Wallis test were used for between-group analyses. RESULTS: Two-week treatment with a 0.1% chlorhexidine mouthwash slightly reduced the gingival inflammation associated with periodontitis. We observed a significant decrease in Gram-negative, facultative anaerobes and micro-aerophiles, and a significant increase in Gram-positive cocci. No increase in the treatment effect was demonstrated by irrigation of the periodontal pockets. CONCLUSION: The 0.1% chlorhexidine mouthwash showed limited beneficial effects in the treatment of periodontitis patients.

Histological analysis of the Ankylos peri-implant soft tissues in a dog model.

PURPOSE: The importance of the soft tissue-implant interface is enhanced by the presence of a microgap between the implant and the abutment, which represents a contamination site for bacteria. The aim of this study was to investigate the interface between the Ankylos gap-free implant system and the surrounding soft tissues in a dog model. MATERIALS AND METHODS: Six Labrador dogs were included in the study and two Ankylos implants were inserted per dog. The dogs were killed 6 months after abutment placement without functional loading and without plaque control. The implants were analysed histologically by scanning electron microscopy, light microscopy, and histomorphometry. RESULTS: Some sections exhibited histologic signs of a mild inflammation. The connective tissue between the most apical epithelial cells of the junctional epithelium and the alveolar crest was characterized by collagen fibers running from the periosteum and the alveolar crest toward the oral epithelium and, in front of the cone-shaped abutment, by a narrow zone of extracellular matrix with a few collagen fibers. CONCLUSION: Compared with results obtained in other studies using different types of implant (Astra, Bränemark, ITI), the Ankylos implant showed a higher length and a larger width of connective tissue contact as well as a shorter epithelial downgrowth. The absence of a microgap in the Ankylos system could explain the histologic mild inflammation in the connective tissue.