scholarly journals Effect of Bleaching and Ca(OH)2 Dressing on the Bond Strength of Fiberglass Posts to Root Dentine

2019 ◽  
Vol 13 (03) ◽  
pp. 335-342
Author(s):  
Iane Souza Nery-Silva ◽  
Gabriela Rover ◽  
Maybell Tedesco ◽  
Lucas da Fonseca Roberti Garcia ◽  
Eduardo Antunes Bortoluzzi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Bond Strength ◽  
Failure Modes ◽  
Root Canal Filling ◽  
Multiple Comparison Test ◽  
Significant Difference ◽  
Frequent Failure ◽  
Push Out ◽  
Scanning Electron

Abstract Objective The purpose of this study was to evaluate the effect of the intracoronary bleaching and calcium hydroxide (Ca(OH)2) dressing use, on the bond strength (BS) of fiberglass posts to root dentine. Materials and Methods After root canal filling of 40 bovine incisors, a 2-mm thick cervical plug was fabricated 2 mm below the cementum–enamel junction. Seven days later, teeth were randomly distributed into four groups (n = 10), as follows: G1 no bleaching, followed by immediate post cementation; G2 bleaching and immediate post cementation; G3 bleaching, dressing with Ca(OH)2 for 7 days, and post cementation; and G4 bleaching, no dressing, and post cementation after 7 days. The roots were transversally cut into 1-mm thick slices to perform the push-out test (0.5 mm/min). Failure modes were assessed under scanning electron microscopy. Statistical Analysis The analysis of variance (two-way ANOVA) was performed, followed by the supplementary Tukey multiple comparison test (a = 5%). Results No significant difference for BS was observed among groups. Considering the different root thirds, G1 had higher BS values for the cervical third in comparison with the apical one (p < 0.05). The most frequent failure modes were adhesive between cement/dentine (G1); cohesive at the post (G2 and G3), and mixed (G4). Conclusions The BS of the fiberglass posts to root dentine was not affected by the intracoronary bleaching and the use of Ca(OH)2 dressing.

scholarly journals Resistance to Dislodgement of REBILDA® Post System to Intraradicular Dentin

2017 ◽  
Vol 19 (2) ◽  
pp. 47
Author(s):  
Daphne Ross DDS ◽  
Carlos E. Filloy Esna DDS ◽  
Juan Carlos Ramírez-Barrantes DDS, MSD, PhD
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Bond Strength ◽  
Adhesive Systems ◽  
Root Reinforcement ◽  
Significant Difference ◽  
Group 2 ◽  
Push Out ◽  
Scanning Electron ◽  
Group 1

Currently there is controversy in the literature about clinical and adhesive effectiveness with respect to adhesive systems aimed to  root reinforcement. Thus, the objective of this study was to evaluate the Push-Out bond strength between the Rebilda® post system and the intraradicular dentine. Thus, 28 unirradicular teeth were used, cut and standardized in 16 mm. The root segments were submitted to endodontic treatment; and then randomly divided into two groups, Group 1 (n = 14): Rebilda® DC + Futurabond DC; Group 2 (n = 14): RelyX ARC + Adper Scothbond Multipurpose Plus. Ten specimens from each group were submitted  to the Push-Out Test. The remaining 4 specimens from each group were prepared for Scanning Electron Microscopy (SEM) in order to evaluate the formation of resinous extensions at the post-cement-dentin interface. Group 2 showed better results when compared to Group 1 regarding bond strength and in formation of resinous extensions or tags, but there was no statistically significant difference (p>0.05). It was concluded that the REBILDA® Post System promotes adequate bond strength to intraradicular dentin.

scholarly journals Comparison of two adhesive systems of various polyetheretherketone (PEEK) composites on the shear bond strength

2021 ◽  
Vol 11 (2) ◽  
pp. 54-61
Author(s):  
Fatih Demirci ◽  
Samet Tekin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Bond Strength ◽  
Surface Properties ◽  
Shear Bond Strength ◽  
Failure Modes ◽  
Testing Machine ◽  
Fiber Reinforced ◽  
Adhesive Systems ◽  
Scanning Electron

Aim: In this in vitro study, the effect of two adhesive systems applied to surfaces of different polyether-ether-ketone (PEEK) composites on the shear bond strength (SBS) of a composite resin was compared. Methodology: Eighty PEEK specimens were divided into four groups (n=20): Unfilled PEEK (UF), carbon-fiber-reinforced PEEK (CFR), glass-fiber-reinforced PEEK (GFR), and ceramic-reinforced PEEK (CR). Each group was further divided into two subgroups (n=10): Visio.link (VL) and Single Bond Universal (SB). The specimens with 8-mm diameter and 5-mm thickness were prepared. SBS was examined using a universal testing machine. Results were statistically analyzed by multivariate analysis of variance and Tukey’s post-hoc test. Failure modes were analyzed using a stereomicroscope at 20× magnification. Surface properties were examined by scanning electron microscopy. The surface properties of the specimens were examined by scanning electron microscopy (SEM).  Results: Effect of different PEEK and adhesive systems on SBS was found to be statistically significant (p<0.05). SBS values for CFR-VL and UF-VL groups were statistically more significant than those for CFR-SB and UF-SB groups (p=0.001). SBS values for the GFR-VL group were statistically more significant than that for the UF-VL group (p=0.001). SBS values for the CF-SB group were statistically more significant than those for CFR-SB and CFR-SB groups (p=0.001). Failure modes were examined using a stereomicroscope at 20× magnification, and adhesive and mixed failure modes were observed. Conclusion: PEEK composites with different contents and properties can be used in fixed prosthetic restorations. However, additional experimental and clinical studies are required to investigate different PEEK frameworks and composite veneers.   How to cite this article: Demirci F, Tekin S. Comparison of two adhesive systems of various polyetheretherketone (PEEK) composites on the shear bond strength. Int Dent Res 2021;11(2):54-61. https://doi.org/10.5577/intdentres.2021.vol11.no2.1   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

scholarly journals Scanning Electron Microscopy Analysis of the Anterior Capsulotomy Edge: A Comparative Study between Femtosecond Laser-Assisted Capsulotomy and Manual Capsulorhexis

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Daniele Tognetto ◽  
Chiara De Giacinto ◽  
Alberto Armando Perrotta ◽  
Tommaso Candian ◽  
Alessandro Bova ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Femtosecond Laser ◽  
Comparative Study ◽  
Surface Irregularity ◽  
Significant Difference ◽  
Group 2 ◽  
Cut Surface ◽  
Scanning Electron ◽  
Group 1

Purpose. To compare the capsule edges ultrastructure obtained by two femtosecond laser-assisted cataract surgery (FLACS) platforms and manual continuous curvilinear capsulorhexis (CCC) using scanning electron microscopy (SEM). Setting. Eye Clinic, University of Trieste, Italy. Design. Experimental comparative study. Methods. 150 anterior capsules were collected and divided into three groups as follows: Group 1 (50 capsules) obtained with manual CCC, Groups 2 and 3 (each with 50 capsules) obtained with the Catalys Laser and the LenSx Laser, respectively. All samples were imaged by means of SEM and regularity of the cut surface, and thickness of the capsule edge were evaluated and compared. Results. All femtosecond laser (FSL) capsules were perfectly circular, whereas some alteration of the circular shape was observed in the manual ones. Group 1 showed a smooth and regular capsule edge without any surface irregularity, conversely Groups 2 and 3 showed postage-stamp perforations on the capsule edge. The cut surface irregularity value in Group 2 was 1.4 ± 0.63, while it was 0.7 ± 0.49 in Group 3 (p<0.05). Group 1 had a significantly lower thickness of the capsule edge than the FSL groups (p<0.05). No statistically significant difference in the capsule edge thickness between the FSL groups was found (p=0.244). Conclusions. Despite the presence of slight cut surface irregularities, both FSL capsulotomies showed a better geometry and circularity than the manual ones. Capsulotomy specimens obtained using both FSL capsulotomies showed laser-induced alterations of the capsule edge when compared with smooth and regular edges obtained using manual CCC.

scholarly journals Effects of Long Durations of RF–Magnetron Sputtering Deposition of Hydroxyapatite on Titanium Dental Implants

2021 ◽  
Author(s):  
Ihab Nabeel Safi ◽  
Basima Mohammed Ali Hussein ◽  
Hikmat J. Aljudy ◽  
Mustafa S. Tukmachi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Magnetron Sputtering ◽  
Dental Implants ◽  
Substrate Surface ◽  
Rf Magnetron Sputtering ◽  
P Value ◽  
Edx Analysis ◽  
Significant Difference ◽  
Scanning Electron

Abstract Objectives Dental implant is a revolution in dentistry; some shortages are still a focus of research. This study use long duration of radiofrequency (RF)–magnetron sputtering to coat titanium (Ti) implant with hydroxyapatite (HA) to obtain a uniform, strongly adhered in a few micrometers in thickness. Materials and Methods Two types of substrates: discs and root form cylinders were prepared using a grade 1 commercially pure (CP) Ti rod. A RF–magnetron sputtering device was used to coat specimens with HA. Magnetron sputtering was set at 150 W for 22 hours at 100°C under continuous argon gas flow and substrate rotation at 10 rpm. Coat properties were evaluated via field emission scanning electron microscopy (FESEM), scanning electron microscopy–energy dispersive X-ray (EDX) analysis, atomic force microscopy, and Vickers hardness (VH). Student’s t-test was used. Results All FESEM images showed a homogeneous, continuous, and crack-free HA coat with a rough surface. EDX analysis revealed inclusion of HA particles within the substrate surface in a calcium (Ca)/phosphorus (P) ratio (16.58/11.31) close to that of HA. Elemental and EDX analyses showed Ca, Ti, P, and oxygen within Ti. The FESEM views at a cross-section of the substrate showed an average of 7 µm coat thickness. Moreover, these images revealed a dense, compact, and uniform continuous adhesion between the coat layer and the substrate. Roughness result indicated highly significant difference between uncoated Ti and HA coat (p-value < 0.05). A significant improvement in the VH value was observed when coat hardness was compared with the Ti substrate hardness (p-value < 0.05). Conclusion Prolonged magnetron sputtering successfully coat Ti dental implants with HA in micrometers thickness which is well adhered essentially in excellent osseointegration.

Microleakage Evaluation of Composite Restorations Following Papain-Based Chemo-Mechanical Caries Removal in Primary Teeth

2017 ◽  
Vol 41 (1) ◽  
pp. 53-61 ◽  
Author(s):  
Marwa Abdel Hafez ◽  
Mona Elkateb ◽  
Sonia El Shabrawy ◽  
Amel Mahmoud ◽  
Omar El Meligy
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Microscopy Study ◽  
Hybrid Layer ◽  
Composite Restorations ◽  
Nail Polish ◽  
Significant Difference ◽  
Drilling Method ◽  
Caries Removal ◽  
Scanning Electron

Aim: To evaluate the microleakage of composite restorations following Papain-based chemo-mechanical caries removal compared to the conventional drilling method. The characteristic of the hybrid layer was also studied using scanning electron microscopy. Study design: The sample included thirty freshly extracted and exfoliated primary molars with open proximal carious dentin lesions. Teeth were divided into two equal groups, according to method of caries removal. Following caries removal, cavity preparations were restored with composite resin. After thermocycling, teeth were sealed apically and coated with nail polish except the surface of restorations and the surrounding 1mm. Teeth were immersed in basic fuschin dye solution, then they were sectioned mesiodistally. The extent of dye penetration was detected using a light stereomicroscope. After microleakage test, the resin/dentin interface was examined using scanning electron microscopy. Results: There was no significant difference in the degree of leakage between both groups. In the Papacarie group, longer and numerous resin tags were observed with statistically significant thicker hybrid layer than those following the drilling method. However, there was no significant difference between the diameters of resin tags of both groups. Conclusions: Papacarie does not adversely affect the microleakage of composite restorations and provides a suitable surface for bonding.

scholarly journals Prosthetic laboratory influence on the vertical misfit at the implant/UCLA abutment interface

2007 ◽  
Vol 18 (2) ◽  
pp. 139-143 ◽  
Author(s):  
Gustavo Augusto Seabra Barbosa ◽  
Paulo Cézar Simamoto Júnior ◽  
Alfredo Júlio Fernandes Neto ◽  
Maria da Glória Chiarello de Mattos ◽  
Flávio Domingues das Neves
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Casting Process ◽  
Significant Difference ◽  
Scanning Electron

An inadequate fit at the abutment/implant interface can generate mechanical and biological problems. The laboratorial stages could induce misfit in such interface when the castable UCLA abutment type is used. The purpose of this study was to comparatively evaluate the performance of three prosthetic laboratories (Labs A, B and C) by vertical fit analysis of castable UCLA abutments on the casting and soldering stages of the same prosthesis. Four fixed prostheses were built by each laboratory using castable UCLA abutments. The evaluation was made by scanning electron microscopy under 500x magnification in the mesial and distal regions of each element of the prosthesis, totalizing 24 measurements per laboratory. The results were analyzed statistically by Kruskal-Wallis test (p<0.05). In the casting process, the values presented by the laboratories differed significantly to each other (p=0.004). After soldering, the values presented by the laboratories showed no significant difference (p=0.948). It may be concluded that the fit values obtained in the casting stage of UCLA abutments can be influenced when processed by different laboratories, and that conventional soldering itself increased the degree of framework misfit, regardless of which laboratory made it.

Problems associated with ageing squid from their statoliths: towards a more structured approach

1994 ◽  
Vol 6 (2) ◽  
pp. 215-222 ◽  
Author(s):  
Marek R. Lipinski ◽  
M. Deon Durholtz
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Regression Analysis ◽  
Light Microscopy ◽  
The Other ◽  
Etching Solution ◽  
Significant Difference ◽  
Structured Approach ◽  
Fish Otoliths ◽  
Scanning Electron

It appears that squid statoliths cannot yet be regarded as accurate an ageing tool as fish otoliths. Statoliths from the same pair, prepared differently for viewing and counting increments, were compared. Increment counts do not imply age in days, because this was not validated. One statolith from each pair was examined by light microscopy (LM) after preparation following a new method. The other was viewed by Scanning Electron microscopy (SEM) with a modified etching solution. Shape of each statolith was similar when compared by multiple regression analysis (11 variables, n=53). There was a weak but significant difference between sexes (statoliths of females were slightly larger). All other differences were insignificant. Microscopic observation and increment counts of increments were successfully carried out for 37 pairs of statoliths. Significant differences between two independent counts were found for the LM method, but no significant differences were found between two independent SEM counts. Counts were significantly different when interpreted by both LM and SEM, probably because of poor resolution in the LM readings and over-resolution (growth layers prominent and numerous) in those read by SEM. Recommendations are made on how ageing studies, based on statoliths, should be structured and the results evaluated.

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