1,720,972 research outputs found
Microscopical and chemical surface characterization of the gingival portion and connection of an internal hexagon abutment before and after different technical stages of preparation
No full textAim: This study was aimed to assess contaminants on the abutment surface close to the implantabutment interface and the connection, after common technical protocols.
Materials and methods: A total of 40 abutments were divided into four groups: control group
(abutment removed from the plastic envelop), test group1 (milled), test group2 (milled and
polished), test group3 (milled, polished and steamed). Groups were subjected to scanning electron
microscope (SEM) analysis. Pollution particles were counted and measured. Mean values and
standard deviation (SD) were calculated. To evaluate any difference between groups Wilcoxon
Signed Rank Test was conducted. In addition, contaminant chemical characterization was
investigated by Energy-dispersive X-ray spectroscopy (EDX).
Results: Control group presented minimal amount of pollution (mean value of 2.1 spots [SD: 1.66]
covering 0.004% of the surface). On the other hand, SEM analysis revealed on the abutment
surface a mean value of 115.9 (SD: 32.27), 162 (SD: 21.17), and 32.5 (SD: 9.73) spots, respectively, in
Test group 1, 2, and 3. Micro-particles covered the 0.025%, 0.057%, 0.0404% of the surface,
respectively, in Test group 1, 2, and 3. On the connection, SEM analysis revealed a mean value of
61.9 (SD: 9.07), 39 (SD: 12.35), 42.1 (SD: 8.59) spots, respectively, in Test group 1, 2, and 3. Microparticles covered the 0.0774%, 0.0869%, and 0.0392% of the surface, respectively, in Test group 1,
2, and 3. Spots were identified by EDX as micro-particles of lubricant and titanium smear layer. All
differences were statistically significant.
Conclusions: After technical procedures, presence of contaminants on the abutment surface in
contact with the peri-implant tissues was confirmed. To prevent that such debris could interfere
with biological stability of peri-implant tissues and, thus, enhance the implant-prosthesis
integration, different cleaning protocols should be evaluated
Implant-abutment connection deformation after prosthetic procedures: An in vitro study
No full textThis study tested the possible damage to the internal implant connection provoked by repeated disconnection and reconnection of prosthetic components. Using a light-structured scanner, connection deformation was inferred by threedimensional (3D) positional changes of a "reference" abutment before and after multiple dis- and reconnections. Measurements were taken after 1, 2, 5, 10, and 20 insertions of titanium abutments in 16 internal hexagon implants. Statistical analysis revealed that multiple dis- and reconnections could cause a deformation in the implant-abutment connection, proportional to the number of insertion procedures. However, below the threshold of 10 cycles, 3D deformation values were minimal
Hard tissue response to argon plasma cleaning/sterilisation of customised titanium abutments versus 5-second steam cleaning: results of a 2-year post-loading follow-up from an explanatory randomised controlled trial in periodontally healthy patients.
No full textPurpose: The aim of this triple-blinded randomised controlled trial was to test if argon plasma cleaning/ sterilisation of customised abutments can affect peri-implant marginal bone levels when compared to 5 seconds of steam cleaning.
Materials and methods: A total of 20 consecutive periodontally healthy patients requiring single implant-supported restorations in the maxillary premolar or anterior area were selected. All patients received a single implant. At abutment connection, customised abutments were randomly allocated to control (subjected only to usually adopted steam cleaning, CG) and test groups (subjected to plasma cleaning/sterilisation, TG). Abutments were screwed in at 32 Ncm, provisional restorations adapted and periapical radiographs were taken using customised film holders. Two weeks later, definitive restorations were placed. Patients were followed-up for 2 years post-loading. Outcome measures were implant/crown success, complications, periapical marginal bone level changes on periapical standardised radiographs, and microbiological analyses of the abutments after customisation and cleaning procedures but before connection. Comparisons between groups were performed by independent sample t tests (significance threshold of P ≤ 0.05).
Results: No patient dropped out 2 years after loading. The presence of bacterial growth (staphylococci, including Staphylococcus aureus) was observed only on the CG abutments. No implant failed and no complications occurred. After 2 years of prosthetic loading, radiographic analysis revealed a statistically significantly higher mean bone loss for the CG group (mean difference 0.4 mm; 95% CI 0.08-0.73; P = 0.018).
Conclusions: This study suggests that removal of contaminants from titanium abutments using plasma of argon can allow for better bone level maintenance when compared to 5-second steam cleaning of titanium abutments. It is therefore important to use cleaned and sterilised customised abutments in patients
Zirconia-composite bonding after plasma of argon treatment.
No full textPURPOSE:
To compare the shear bond strength (SBS) values of resin cement to zirconia treated with a new activating method.
MATERIALS AND METHODS:
Forty-five zirconia specimens were divided into three groups: no treatment (group 1), plasma of argon cleaning for 375 seconds (group 2), and plasma of argon cleaning for 750 seconds (group 3). Composite cylinders were bonded with a self-adhesive cement. After 40 days of water storage, specimens were subjected to the SBS test. Data were analyzed with one-way analysis of variance and the Neuman-Keuls multiple comparison test.
RESULTS:
Test groups obtained SBS values significantly higher (101% for group 2 and 81% for group 3) than controls.
CONCLUSION:
Plasma of argon appeared to improve bonding between zirconia and resin cement
Implant abutment screw reverse torque values before and after plasma cleaning
No full textThis in vitro study analyzed the reverse torque (RevT) of abutment screws following different cleaning treatments. A convenience sample of 50 customized titanium abutment screw complexes was divided into five groups: cleaning by steam (control group), cleaning by Argon plasma (test groups 1 and 2 [with chlorhexidine gel]), and replacement of old screws with new ones (test groups 3 and 4 [with chlorhexidine gel]). Abutments were screwed onto implants and tested for RevT. The RevT of the test groups was significantly higher than that of the control group. No statistically significant difference between test groups was noted except between groups 2 and 3
Cleaning procedures on customized abutments: microscopical, microbiological and chemical analysis
No full textBackground: Abutment connection should be considered as a surgical “sterile” procedure, since the abutment could get in contact with bone and connective tissue. However, evidence on the effect of technical steps and cleaning procedures on abutment surface characteristics are lacking in dental-related Literature.
Aim: This study was aimed to assess pollutions and microbiologic contaminants on the abutment surface close to implant-abutment junction (IAJ) and connection, after common technical protocols and different cleaning procedures.
Material and methods: 20 commercially available grade 5 Titanium implant/abutments were milled (Control Group1, CG1), polished (Control Group2, CG2) and cleaned by steam (Control Group3, CG3). Abutments were then divided in two groups of 10: one group was subjected to ultrasonic cleansing (Test Group1, TG1), the other underwent plasma of Argon treatment (Test Group2, TG2).
For all control and test specimens, SEM analysis and Energy-dispersive X-ray spectroscopy (EDAX) microanalysis were performed in order to count and chemically characterize pollution micro-particles, both on the abutment surface and implant-abutment connection.
Additionally specific DNA probes were designed to detect Staphilococcus Aureos and Epidermidis. DNA was extracted from all control and test samples and amplified by Q-PCR methods. Positive controls were used to check experimental results.
For all groups, mean values and SD of micro-particles were calculated. Comparisons were performed by paired samples t-Test. The level of statistical significance was set at p≤0.05.
Results: On the abutment surface close to AIJ, SEM analysis revealed on average 115.9 (±32.27), 162 (±21.17) and 32.5 (±9.73) micro-particles, respectively in CG1, CG2 and CG3. In TG1 and TG2, number of micro-particles was on average respectively 1.09 (±0.51), and 1.14 (±0.52)
On the connection, SEM analysis showed a mean value of 61.9 (±9.07), 39 (±12.35), 42.1 (±8.59) spots respectively in CG1, CG2 and CG3. In TG1 and TG2, micro-particles were on average respectively 1.13 (±0.48) and 1.34 (±0.71).
Statistical comparisons between means of control and test groups were significant for all levels. On the contrary, difference between test groups was not significant.
EDAX microanalysis identified all micro-particles as residual of lubricant mixed with Titanium and traces of other metals.
Microbiological analysis detected no Staphilococcus Epidermidis, whereas conflicting results were obtained as regard Staphilococcus Aureos.
Conclusions and clinical implications: After technical procedures, presence of contaminants and bacteria on the abutment was confirmed. To prevent that such debris could interfere with biological stability of peri-implant tissues, ultrasonic and plasma of Argon cleaning protocols can be advantageously adopted
Shear bond strength of veneering porcelain to zirconia after argon plasma treatment.
No full textPURPOSE:
The aim of this study was to investigate if argon plasma cleaning increases the shear bond strength between zirconia and veneering ceramic surfaces.
MATERIALS AND METHODS:
Ninety tablets of densely sintered yttriastabilized tetragonal zirconia polycrystal were divided into three groups according to cleaning treatment (steam cleaning or plasma of Argon for 375 or 750 seconds). Groups were divided into two subgroups according to the application of a ceramic liner (A = liner, B = no liner).
RESULTS:
Within subgroup A, argon plasma cleaning significantly decreased shear bond strength. In subgroup B, the plasma treatment increased the shear bond strength, but the differences were not statistically significant. Subgroup A demonstrated lower shear bond strength compared to subgroup B
Implant abutment screw reverse torque values before and after plasma cleaning.
No full textAbstract
This in vitro study analyzed the reverse torque (RevT) of abutment screws following different cleaning treatments. A convenience sample of 50 customized titanium abutment screw complexes was divided into five groups: cleaning by steam (control group), cleaning by Argon plasma (test groups 1 and 2 [with chlorhexidine gel]), and replacement of old screws with new ones (test groups 3 and 4 [with chlorhexidine gel]). Abutments were screwed onto implants and tested for RevT. The RevT of the test groups was significantly higher than that of the control group. No statistically significant difference between test groups was noted except between groups 2 and 3
Hard tissue response to argon plasma cleaning/ sterilisation of customised titanium abutments versus 5-second steam cleaning: Results of a 2-year post-loading follow-up from an explanatory randomised controlled trial in periodontally healthy patients
No full textPurpose: The aim of this triple-blinded randomised controlled trial was to test if argon plasma cleaning/ sterilisation of customised abutments can affect peri-implant marginal bone levels when compared to 5 seconds of steam cleaning.
Materials and methods: A total of 20 consecutive periodontally healthy patients requiring single implant-supported restorations in the maxillary premolar or anterior area were selected. All patients received a single implant. At abutment connection, customised abutments were randomly allocated to control (subjected only to usually adopted steam cleaning, CG) and test groups (subjected to plasma cleaning/sterilisation, TG). Abutments were screwed in at 32 Ncm, provisional restorations adapted and periapical radiographs were taken using customised film holders. Two weeks later, definitive restorations were placed. Patients were followed-up for 2 years post-loading. Outcome measures were implant/crown success, complications, periapical marginal bone level changes on periapical standardised radiographs, and microbiological analyses of the abutments after customisation and cleaning procedures but before connection. Comparisons between groups were performed by independent sample t tests (significance threshold of P ≤ 0.05).
Results: No patient dropped out 2 years after loading. The presence of bacterial growth (staphylococci, including Staphylococcus aureus) was observed only on the CG abutments. No implant failed and no complications occurred. After 2 years of prosthetic loading, radiographic analysis revealed a statistically significantly higher mean bone loss for the CG group (mean difference 0.4 mm; 95% CI 0.08-0.73; P = 0.018).
Conclusions: This study suggests that removal of contaminants from titanium abutments using plasma of argon can allow for better bone level maintenance when compared to 5-second steam cleaning of titanium abutments. It is therefore important to use cleaned and sterilised customised abutments in patients
Zirconia-composite bonding after plasma of argon treatment
No full textPurpose: To compare the shear bond strength (SBS) values of resin cement to zirconia treated with a new activating method. Materials and Methods: Forty-five zirconia specimens were divided into three groups: no treatment (group 1), plasma of argon cleaning for 375 seconds (group 2), and plasma of argon cleaning for 750 seconds (group 3). Composite cylinders were bonded with a self-adhesive cement. After 40 days of water storage, specimens were subjected to the SBS test. Data were analyzed with one-way analysis of variance and the Neuman-Keuls multiple comparison test. Results: Test groups obtained SBS values significantly higher (101% for group 2 and 81% for group 3) than controls. Conclusion: Plasma of argon appeared to improve bonding between zirconia and resin cemen
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