title: Resistance to bacterial aggression involving exposed nonresorbable membranes in the oral cavity.
abstract: Bacterial colonies split implanted membranes that are exposed to oral biologic fluids as a consequence of dehiscence. The clinical and histologic behavior of 14 implanted polyurethane membranes was observed during the period of exposure to oral fluids for 2, 3, 4, and 6 weeks and without dehiscence (after 8 weeks). Statistical analysis indicated that the decrease in the number of neutrophils after 5 weeks, associated with the increase in the number of activated fibroblasts, cellular debris, giant cells, and aggression of bacteria, was statistically significant (from P < .05 and P < .01 for activated fibroblasts to P <.005 and P < .001 for neutrophilic cells). The increase in bacterial passage through the polyurethane membranes and in the number of giant cells and cellular debris after 8 weeks represents late dissolution of the membranes; the progressive increase of activated fibroblasts is significant because the longer the membrane resists, the better the cells can grow and give way to the process of tissue regeneration.
authors.affiliation: Odontomatologist, Odontoiatric Center, Milan, Italy.
authors.forename: G C
authors.initials: GC
authors.lastname: Leghissa
authors.forename: A R
authors.initials: AR
authors.lastname: Botticelli
mesh_terms: D016301:Alveolar Bone Loss / Q000601:surgery; D018407:Bacterial Physiological Phenomena; D002452:Cell Count; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D005260:Female; D005347:Fibroblasts / Q000473:pathology / Q000502:physiology; D015726:Giant Cells / Q000473:pathology; D016557:Guided Tissue Regeneration, Periodontal; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008567:Membranes, Artificial; D009055:Mouth / Q000382:microbiology* / Q000473:pathology; D009504:Neutrophils / Q000473:pathology; D010510:Periodontal Diseases / Q000601:surgery; D011140:Polyurethanes; D012038:Regeneration; D012463:Saliva / Q000166:cytology / Q000382:microbiology; D013499:Surface Properties; D013529:Surgical Wound Dehiscence / Q000382:microbiology / Q000473:pathology; D014081:Tooth Extraction
chemical_list: D015921:Dental Implants; D008567:Membranes, Artificial; D011140:Polyurethanes