ABSTRACT
OBJECTIVE: The objective of this case-control study was to quantify the immune responsiveness in individuals with type 2 diabetes (T2D) as compared with patients without diabetes (NT2D) diagnosed with periodontitis. RESEARCH DESIGN AND METHODS: Peripheral blood was collected from 20 patients with moderate-to-severe chronic periodontitis (10 T2D, 10 NT2D). Blood samples were stimulated with ultrapure Porphyromonas gingivalis and Escherichia coli lipopolysaccharide (LPS) for 24â hours. 14 cytokines/chemokines were quantified in culture supernatants using multiplex technology. RESULTS: T2D individuals demonstrated higher unstimulated levels of interleukin 6 (IL-6), IL-1ß, tumor necrosis factor α, interferon γ, IL-10, IL-8, macrophage inflammatory protein 1α (MIP1α), and 1ß (MIP1ß), and higher stimulated levels of IL-6, IL-8, IL-10, MIP1α and MIP1ß, along with lower unstimulated and stimulated levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) when compared with NT2D (p<0.05). Importantly, the LPS-induced levels of IL-6, IL-8, IL-10 and MIP1α strongly correlated with severity of disease, measured by pocket depths (PD), within the T2D group (r(2)≥0.7, p<0.05), but not within NT2D. CONCLUSIONS: Among patients with chronic periodontitis, patients with T2D seem to have an enhanced LPS-induced immune responsiveness than individuals without diabetes, which correlates with periodontal disease severity, concomitant with a less robust GM-CSF response. This data may in part explain the higher predisposition to periodontitis in this population.
ABSTRACT
Bacterial colonization of the fixture-abutment interface (FAI) microgap may contribute to increased marginal bone loss. The contribution of loading on bacterial colonization has not been thoroughly evaluated with in vitro experiments. The aim of this study was to evaluate the effect of dynamic loading on the colonization of oral microorganisms in the FAI microgap of dental implants with internal Morse-taper connection. Forty implants were divided into two groups (n = 20/group) based on subjection to dynamic loading conditions. Both Group 1 and 2 were comprised of fixtures that connected to standard abutments and allowed to incubate in a bacterial solution of Escherichia coli . The specimens of Group 2 were loaded with 500 000 cycles of 50 N using a chewing simulator. Following disconnection of fixtures and abutments, microbial samples were taken from the threaded portion of the abutment, plated and cultured under appropriate conditions. One of the 20 implants of Group 1 and 4 of the 20 implants of Group 2 had FAI microgaps colonized by E coli . With the limits of this study, it indicates that implants with internal Morse-taper connection exhibited minimal bacterial penetration down to the threaded part of the FAI and that dynamic loading increases the potential for such bacterial penetration.
