Demineralizing action of EGTA in endodontics.

The demineralization of dentin obtained by treatment with a chelating agent ethylene diamminotetracetic acid (EDTA) or ethylene glycol-bis(β-aminoethyl ether)-N-tetraacetic acid (EGTA), is a dynamic process involving chelation and solubilization. The actions of the EDTA and EGTA on dentin are influenced by the pH. Increasing mM concentrations of EDTA or EGTA the equivalent pH decreases in a similar slope to 80 mM chelator concentration. Increasing the chelator concentration different data were obtained: with EGTA the pH decreases slightly while with EDTA goes back up to the initial values. After 80 mM, EDTA reduces the activity on the dentin, and EGTA continues to work at higher concentrations. We demonstrated that EGTA solubilized more of 60% of dentin while EDTA gives about 20% at the maximal of the solubility

Influence of bacterial colonization of the healing screws on peri-implant tissue

Abstract Background/purpose A bacterial adhesion to implant surfaces is a first stage of peri-implant mucositis and peri-implantitis. The aim of this longitudinal study was to examine the quantitative and qualitative biofilm formation on healing screws and the presence of periodontal pathogens in peri-implant crevicular fluid (PCF). In each of the 30 participants, one healing screw was adapted to every single implant. Materials and methods Thirty patients, 18 females and 12 males, were selected. Thirty healing abutments were left in situ for 20, 30 and 90 days. At regular times, the presence/absence of bleeding on probing (BOP) was determined. The specific periodontal pathogens were determined in PCF, by polymerase chain reaction (PCR). After 20, 30 and 90 days, the healing screws were removed and analyzed to establish the total bacterial count by a culture method. Results BOP+ increased significantly after 90 days. Biofilm was detected on all healing abutments and the number of cultivable oral flora showed a significant increase from 20 days to 30 days and to 90 days. At 90 days, the anaerobic counts constituted the bulk of plaque examined and Veillonella spp. were present in higher percentages levels (19.82%) among the Gram-negative bacteria. No significant differences among the experimental groups were detected in the frequencies of detection of each monitored bacteria in PCF. Conclusion The healing screws left in situ for a period of 90 days caused a peri-implant inflammation and the presence of periodontal pathogenic bacteria in the peri-implant sulcus, due to the plaque accumulation on screw surfaces

Microbiological and biochemical effectiveness of an antiseptic gel on the bacterial contamination of the inner space of dental implants: a 3-month human longitudinal study.

Microbial penetration inside the implant's internal cavity produces a bacterial reservoir that is associated with an area of inflamed connective tissue facing the fixture-abutment junction. The aim of this clinical trial is to evaluate the effectiveness of a 1% chlorhexidine gel on the internal bacterial contamination of implants with screw-retained abutments and on the level of AST secreted in peri-implant crevicular fluid. Twenty-five patients (aged 29 to 58 years) each received one implant. Three months after the end of the restorative treatment, and immediately after a clinical and radiographic examination and the abutment removal, microbiological samples were obtained from the internal part of each fixture and biochemical samples were collected by peri-implant sulci. The patients were then divided into two groups: the control (CG; n=10) and test (TG; n=15) groups. The CG had the abutment screwed into place and the crown cemented without any further intervention. In contrast, before the abutment placement and screw tightening, the TG had the internal part of the fixture filled with a 1% chlorhexidine gel. Three months later, the same clinical, microbiological and biochemical procedures were repeated in both groups. Total bacterial count, specific pathogens and AST activity were detected. The clinical parameters remained stable throughout the study. From baseline to the 3-month examination, the total bacterial counts underwent a significant reduction only in the TG. In contrast, the AST activity showed a significant increase in the CG. The administration of a 1% chlorhexidine gel appears to be an effective method for the reduction of bacterial colonization of the implant cavity and for safeguarding the health status of peri-implant tissue over a 3-month administration period

Quality of Life: Effects of Physical Activity in an Anthropometric, Cognitive and Psychosocial Background, and Variation of Odontoiatric Parameters

The "Quality of Life" project arises from the need to observe and define the existing interconnection between a "healthy" lifestyle and the quality of life perceived by people. Starting from the W.H.O. (World Health Organization) definitions of quality of life and health, and analyzing the studies that describe the benefits of both movement physical and mental, a protocol three months has been set for the pursuit of a diet and personalized training. For this purpose, 20 healthy subjects from the 1st year of the Physiotherapy degree, who had never practiced sports at an agonistic level, have been recruited. All individuals were subject to initial evaluations to define psycho-physical wellbeing, then they have been divided into two groups: the first group, defined as experimental, followed the protocol for the duration of the study, while the second, was only subject to evaluation. At the end of the three months period, the subjects of both groups were evaluated twice, the first immediately after the last training session, the second was evaluated one month from the latter. The final evaluation aimed at verifying a possible conservative effect on modification of experimental group parameters, even when physical activity and nutrition were not supervised by us. The ultimate goal of the project was to specifically analyze, after three months, the changes in cognitive memory capacity and concentration, the stress experienced in work or study, and psycho-physical wellbeing perceived by the concerned subjects. Data collected during the three evaluations showed that, in the experimental group, as our scientific protocol has altered all these parameters in terms of quality of life in positive terms, modifications are susceptible to changes in the event that physical activity and proper nutrition are not followed

Demineralizing Action of EGTA in Endodontics

The demineralization of dentin obtained by treatment with a chelating agent ethylene diamminotetracetic acid (EDTA) or ethylene glycol-bis(β-aminoethyl ether)-N-tetraacetic acid (EGTA), is a dynamic process involving chelation and solubilization. The actions of the EDTA and EGTA on dentin are influenced by the pH. Increasing mM concentrations of EDTA or EGTA the equivalent pH decreases in a similar slope to 80 mM chelator concentration. Increasing the chelator concentration different data were obtained: with EGTA the pH decreases slightly while with EDTA goes back up to the initial values. After 80 mM, EDTA reduces the activity on the dentin, and EGTA continues to work at higher concentrations. We demonstrated that EGTA solubilized more of 60% of dentin while EDTA gives about 20% at the maximal of the solubility

Functionalization of a Cortical Membrane with a Photodynamic Protocol

Guided bone regeneration (GBR) comprehends the application of membranes to drive bone healing and to exclude non-osteogenic tissues from interfering with bone regeneration. However, the membranes may be exposed to bacterial attack, with the risk of failure of the GBR. Recently, an antibacterial photodynamic protocol (ALAD-PDT) based on a gel with 5% 5-aminolevulinic acid incubated for 45 min and irradiated for 7 min by a LED light at 630 nm, also showed a pro-proliferative effect on human fibroblasts and osteoblasts. The present study hypothesized that the functionalization of a porcine cortical membrane (soft-curved lamina, OsteoBiol) with ALAD-PDT might promote its osteoconductive properties. TEST 1 aimed to verify the response of osteoblasts seeded on lamina with respect to the plate surface (CTRL). TEST 2 aimed to investigate the effects of ALAD-PDT on the osteoblasts cultured on the lamina. SEM analyses were performed to study the topographical characteristics of the membrane surface, the adhesion, and the morphology of cells at 3 days. The viability was assessed at 3 days, the ALP activity at 7 days, and calcium deposition at 14 days. Results showed the porous surface of the lamina and the increase in cell attachment of osteoblasts with respect to controls. The proliferation, the ALP, and bone mineralization activity of osteoblasts seeded on lamina resulted in being significantly higher (p < 0.0001) than controls. Results also showed an additional significative enhancement (p < 0.0001) in the proliferative rate in ALP and calcium deposition after applying ALAD-PDT. In conclusion, the functionalization of the cortical membranes cultured with osteoblasts with the ALAD-PDT improved their osteoconductive properties

Complex Chronic Wound Biofilms Are Inhibited in vitro by the Natural Extract of Capparis spinose

Resistant wound microorganisms are becoming an extremely serious challenge in the process of treating infected chronic wounds, leading to impaired healing. Thus, additional approaches should be taken into consideration to improve the healing process. The use of natural extracts can represent a valid alternative to treat/control the microbial infections in wounds. This study investigates the antimicrobial/antivirulence effects of Capparis spinose aqueous extract against the main chronic wound pathogens: Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. The extract shows phenolic characterization with rutin (1.8 ± 0.14 μg/mg) as the major compound and antibacterial effect against bacteria (S. aureus PECHA 10 MIC 6.25%; P. aeruginosa PECHA 4 MIC 12.50%) without action against C. albicans (MIC and MFC ≥ 50%). Capparis spinose also shows a significant antivirulence effect in terms of antimotility/antibiofilm actions. In particular, the extract acts (i) on P. aeruginosa both increasing its swimming and swarming motility favoring the planktonic phenotype and reducing its adhesive capability, (ii) on S. aureus and P. aeruginosa biofilm formation reducing both the biomass and CFU/ml. Furthermore, the extract significantly displays the reduction of a dual-species S. aureus and P. aeruginosa Lubbock chronic wound biofilm, a complex model that mimics the realistic in vivo microbial spatial distribution in wounds. The results suggest that C. spinose aqueous extract could represent an innovative eco-friendly strategy to prevent/control the wound microbial infection