scholarly journals Shear bond strength of new and recycled brackets to enamel

2006 ◽  
Vol 17 (1) ◽  
pp. 44-48 ◽  
Author(s):  
Stenyo Wanderley Tavares ◽  
Simonides Consani ◽  
Darcy Flávio Nouer ◽  
Maria Beatriz Borges de Araújo Magnani ◽  
Paulo Roberto Aranha Nouer ◽  
...  

The purpose of this study was to evaluate in vitro the shear bond strength of recycled orthodontic brackets. S2C-03Z brackets (Dental Morelli, Brazil) were bonded to the buccal surfaces of 50 extracted human premolars using Concise Orthodontic chemically cured composite resin (3M, USA). The teeth were randomly assigned to 5 groups (n=10), as follows. In group I (control), the bonded brackets remained attached until shear testing (i.e., no debonding/rebonding). In groups II, III and IV, the bonded brackets were detached and rebonded after recycling by 90-mum particle aluminum oxide blasting, silicon carbide stone grinding or an industrial process at a specialized contractor company (Abzil-Lancer, Brazil), respectively. In group V, the bonded brackets were removed and new brackets were bonded to the enamel surface. Shear bond strength was tested in an Instron machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test at 5% significance level. There was no statistically significant difference (p>0.05) between the control brackets (0.52 kgf/mm²), brackets recycled by aluminum oxide blasting (0.34 kgf/mm²) and new brackets attached to previously bonded teeth (0.43 kgf/mm²). Brackets recycled by the specialized company (0.28 kgf/mm²) and those recycled by silicon carbide stone grinding (0.14 kgf/mm²) showed the lowest shear strength means and differed statistically from control brackets (0.52 kgf/mm²) (p<0.05). In conclusion, the outcomes of this study showed that bracket recycling using 90-µm aluminum oxide particle air-abrasion was efficient and technically simple, and might provide cost reduction for orthodontists and patients alike.

2021 ◽  
Vol 45 (3) ◽  
pp. 177-185
Author(s):  
Moaz H Attar ◽  
Medhat A Abdallah ◽  
Hussein A Alharthy ◽  
Omar A El Meligy

Objectives: To investigate the effect of Co-curing versus Staged-curing and No-bonding on retention of different resin-based sealants (RBS). Study design: For shear bond strength (SBS) and microleakage tests, 90 extracted premolars were divided equally into 3 groups (I, II, III). Each group was further subdivided equally into 3 subgroups (a, b, c). No-bonding subgroups did not receive a bonding agent, Staged-curing subgroups received a bonding agent that was cured before sealant application, while Co-curing subgroups received a bonding agent that was cured after sealant application. Seal-it was applied for group I, Helioseal-F for group II and Clinpro for group III. SBS buttons were tested using Instron machine, while microleakage specimens were examined using micro-CT. Results: Clinpro showed the highest SBS values in Staged-curing and No-bonding groups (8.72±2.39, 12.51±3.16) respectively. Staged-curing was significantly greater in SBS values than those for other groups (P&lt;0.05). There was a significant difference in microleakage values of Staged-curing among different RBS (P = 0.003), while there was no significant difference in values of No-bonding and Co-curing among different RBS (P = 0.541, P = 0.521). Conclusions: The use of a bonding agent as Staged-curing was more effective in improving sealant retention than No-bonding and Co-curing.


2002 ◽  
Vol 13 (3) ◽  
pp. 175-178 ◽  
Author(s):  
Maria Cristina Borsatto ◽  
Alma Blásida Elisaur Benitez Catirse ◽  
Regina Guenka Palma Dibb ◽  
Telma Nunes do Nascimento ◽  
Renata Andréa Salvitti de Sá Rocha ◽  
...  

The aim of this study was to evaluate the shear bond strength of a composite resin to dental enamel, using three different surface treatments. Fifteen sound third molars were randomly assigned to three groups. The mesial and distal surfaces were flattened and covered using adhesive tape with a central orifice delimiting the adhesion area (7.07 mm²). Group I, the enamel surface was conditioned with 37% phosphoric acid for 15 s; group II, the surface was treated using air abrasion with aluminum oxide; group III, the enamel surface was treated using an association of air abrasion with aluminum oxide and 37% phosphoric acid. The Single Bond (3M) adhesive system was applied and a Teflon matrix was placed and filled with composite resin Z-100 (3M) and light-cured. The shear bond strength test was performed with a universal testing machine. The acid etching technique and air abrasion with aluminum oxide associated with acid etching had the highest shear bond strength values. Data were subjected to statistical analysis using ANOVA and the Tukey test, and no statistically significant difference in shear bond strength was observed between group I (12.49 ± 2.85 MPa) and group III (12.59 ± 2.68 MPa). In contrast, both groups had statistically better shear bond strengths compared to group II (0.29 ± 0.56 MPa; p<0.05). Air abrasion with aluminum oxide does not substitute acid etching. The association of these methods to obtain adequate adhesion to the substrate is necessary.


2014 ◽  
Vol 85 (3) ◽  
pp. 461-467 ◽  
Author(s):  
Manuela M. Haro Montero ◽  
Ascensión Vicente ◽  
Noelia Alfonso-Hernández ◽  
Manuel Jiménez-López ◽  
Luis-Alberto Bravo-González

ABSTRACT Objective:  To evaluate in vitro the shear bond strength of brackets recycled by sandblasting with aluminum oxide particles of different sizes or reconditioned industrially after successive rebonding. Materials and Methods:  Eighty brackets were bonded and debonded sequentially three times. After the first debonding, brackets were divided into four groups: (group 1) sandblasting with aluminum oxide particles of 25 μ, (group 2) 50 μ, and (group 3) 110 μ, and (group 4) industrial recycling. Bond strength and adhesive material remaining on debonded bracket bases were evaluated for each successive debond. Results:  No significant differences were detected between the four groups following the first recycle (P &gt; .05). After the second recycle, bond strength was significantly greater for the industrially recycled group than the other groups (P &lt; .016). When shear bond strength was compared within each recycling method, the bond strength of sandblasted brackets decreased with the increase of particle size and with each recycle; for the industrially recycled group, no significant differences were detected between the three sequences (P &gt; .016). In the evaluation of bond material remnant, the industrially recycled group left significantly less bond material after successive recycling than the other groups did (P &lt; .016). Within each recycling method, the adhesive remnant decreased significantly after successive debond (P &lt; .016). Conclusions:  Industrial recycling obtained better results than sandblasting after three successive debondings. The brackets' shear bond strength decreased as the size of the aluminum oxide particle used for sandblasting increased and as recycling was repeated.


2017 ◽  
Vol 05 (02) ◽  
pp. 084-089
Author(s):  
Alisha Dhingra ◽  
Ashu Gupta ◽  
Anshu Minocha ◽  
Nayantara Sen

Abstract Aim: The aim of this study was to compare the reversal of shear bond strength of composite to bleached enamel immediately after bleaching followed by application of various antioxidant solutions. Material and Methods: Seventy central incisors were divided into seven groups. Groups I and II served as unbleached and bleached controls respectively. Groups III, IV, V, VI and VII served as the experimental groups and were subjected to 37.5% hydrogen peroxide bleaching followed by 10 min application of 10% sodium ascorbate, 25% alpha-tocopherol, 6.5% grape seed extract, 5% lycopene and 5% green tea extract respectively. Following composite bonding, shear bond strength was determined and the results were analyzed using ANOVA followed by Post Hoc Multiple Comparisons test. Results: The bond strength values for Group I (positive control) were maximum and significantly different than all the other groups except Grape seed extract group (Group V). When compared to Group II (bleached control), all the groups showed significantly higher bond strength. Significant difference in the bond strength values were seen between Group III (10% sodium ascorbate) and Group V. Also values for Group V were significantly different from Group VI (5% lycopene). All the other values showed insignificantly different results. Conclusion: All the antioxidant solutions improved the shear bond strength values after bleaching but only Grape seed extract application reversed the values to the non bleached levels. Lycopene was least effective. Other antioxidants showed comparable results.


2012 ◽  
Vol 17 (4) ◽  
pp. 1-7 ◽  
Author(s):  
Roberto Hideo Shimizu ◽  
Karlos Giovani Grando ◽  
Isabela Almeida Shimizu ◽  
Augusto Ricardo Andriguetto ◽  
Ana Cláudia Moreira Melo ◽  
...  

OBJECTIVE: This in vitro study was designed to evaluate the shear bond strength (SBS) of orthodontic metal brackets bonded by direct and indirect techniques. METHODS: Thirty healthy human maxillary premolar teeth were used. The teeth were divided into three groups of 10 teeth each: Group I - indirect bonding with SondhiTM Rapid-Set system (3M/Unitek), Group II - indirect bonding with TransbondTM XT adhesive system (3M/Unitek) and Group III - direct bonding with TransbondTM XT adhesive system (3M/Unitek). After bonding and obtaining the specimens for the study, the specimens were subjected to SBS testing in a universal testing machine (Emic, model DL-500). The Kolmogorov-Smirnov test was applied to ascertain that the data had a normal distribution and the Bartlett test to check whether there was homogeneity of variance. One-factor analysis of variance was performed and, subsequently, Tukey's test for paired means. A 5% significance level was adopted. RESULTS: The results of Group I were 67.6 (N) and 5.9 (MPa); Group II, 68.9 (N) and 6.1 (MPa) and Group III (control), 92.5 (N) and 8.1 (MPa). CONCLUSION: It can therefore be concluded that the means for Group III were significantly higher compared with Groups I and II in both Newton (N) and Megapascal (MPa) values. The means attained by the indirect bonding technique used in Groups I and II, however, exhibited no statistically significant differences.


2016 ◽  
Vol 17 (12) ◽  
pp. 997-1002 ◽  
Author(s):  
Fahad I Alkhudhairy ◽  
Zeeshan H Ahmad

ABSTRACT Introduction Various bulk-fill materials depending on their composition, viscosity, and flow ability have different physical and mechanical properties. The aim of this in vitro study was to determine and compare the shear bond strength and microleakage properties of activa restorative with other bulk-fill restorative materials surefil (SDR), Biodentine, ever X posterior. Materials and methods Forty permanent premolars were selected for shear bond strength, and 20 permanent premolars were selected with class II cavities on mesial and distal side for microleakage. Universal testing device was used to assess the shear bond strength. Microleakage was checked using dye penetration method under a stereomicroscope. Mean and standard deviation values were calculated from the recorded values. Intergroup comparison was done by one-way analysis of variance (ANOVA) followed by pairwise comparison using Tukey honestly significant difference (HSD) post hoc test. Results The mean shear bond strength was highest for SDR surefil followed by Ever X posterior, Bioactive restorative, and Biodentine respectively. In this study, SDR (surefil) showed better shear bond strength and better microleakage properties compared with the other test materials (F = 186.7157, p < 0.05). Conclusion The result of this study showed that flowable and fiber-reinforced composites have better shear bond strength and microleakage properties. Clinical significance Flowable bulk-fill composite resins can be used as dentin substitutes because of its superior properties. How to cite this article Alkhudhairy FI, Ahmad ZH. Comparison of Shear Bond Strength and Microleakage of Various Bulk-fill Bioactive Dentin substitutes: An in vitro study. J Contemp Dent Pract 2016;17(12):997-1002.


2013 ◽  
Vol 24 (3) ◽  
pp. 279-283 ◽  
Author(s):  
Ana Caroline Silva Gama ◽  
Andre Guaraci de Vito Moraes ◽  
Lilyan Cardoso Yamasaki ◽  
Alessandro Dourado Loguercio ◽  
Ceci Nunes Carvalho ◽  
...  

The purpose of this study was to evaluate in vitro the shear bond strength to enamel, flexural strength, flexural modulus, and contraction stress of one orthodontic composite and two flowable composites. Orthodontic brackets were bonded to 45 human maxillary premolars with the composites Transbond XT, Filtek Z-350 flow and Opallis flow and tested for shear bond strength. For measurement of flexural strength and flexural modulus, specimens were fabricated and tested under flexion. For the contraction stress test, cylindrical specimens were tested and an extensometer determined the height of the specimens. The data were subjected to one-way ANOVA and Tukey's test (α=0.05). The shear bond strength values were significantly lower (p<0.05) for the flowable composites compared with the orthodontic composite. For the flexural strength, no statistically significant difference was found among the composites (p>0.05) while the flexural modulus was significantly higher (p<0.05) for Transbond XT than for Filtek Z-350 flow and Opallis flow. The orthodontic composite presented significantly lower contraction stress values than the flowable composites (p<0.05). The light-activated orthodontic composite material presented higher flexural modulus and shear bond strength and lower contraction stress than both flowable composites.


2007 ◽  
Vol 77 (4) ◽  
pp. 701-706 ◽  
Author(s):  
Rodney G. Northrup ◽  
David W. Berzins ◽  
Thomas Gerard Bradley ◽  
William Schuckit

Abstract Objective: To evaluate and compare the shear bond strengths of two adhesives using two types of brackets: a conventional and a self-ligating bracket system. Materials and Methods: Sixty extracted human premolars were collected. The premolars were randomly divided into three groups of 20 teeth. All three groups were direct bonded. Groups 1 and 2 used light-cured adhesive and primer (Transbond XT) with a conventional (Orthos) and a self-ligating bracket (Damon 2), respectively. Group 3 used a light-cured primer (Orthosolo) and a light-cured adhesive (Blūgloo) with a self-ligating bracket (Damon 2). The specimens were stored in distilled water at 37°C for 40 ± 2 hours, after which they were debonded and inspected for Adhesive Remnant Index (ARI) scoring. Results: The mean shear bond strength was 15.2 MPa for group 1, 23.2 MPa for group 2, and 24.8 MPa for group 3. A one-way analysis of variance and post hoc Tukey test showed significant differences in bond strength (P &lt; .001) between group 1 and groups 2 and 3 but no significant difference (P &gt; .05) between groups 2 and 3. A Weibull analysis demonstrated that all three groups provided sufficient bond strength with over 90% survival rate at normal masticatory and orthodontic force levels. A Kruskal-Wallis test showed no significant difference (P &gt; .05) in ARI scores among all three groups. Conclusions: All three groups demonstrated clinically acceptable bond strength. The Damon 2 self-ligating bracket exhibited satisfactory in vitro bond strength with both adhesive systems used.


2017 ◽  
Vol 11 (01) ◽  
pp. 058-063 ◽  
Author(s):  
Vini Rajeev ◽  
Rajeev Arunachalam ◽  
Sanjna Nayar ◽  
P. R. Arunima ◽  
Sivadas Ganapathy ◽  
...  

ABSTRACT Objective: This in vitro study was designed to assess shear bond strength (SBS) of ormocer flowable (OF) resin as a luting agent, ormocer as an indirect veneer material with portrayal of modes of failures using scanning electron microscope (SEM). Materials and Methods: Sixty maxillary central incisors were divided into Group I, II, and III with 20 samples each based on luting cement used. They were OF, self-adhesive (SA) cement, and total etch (TE) cement. These groups were subdivided into “a” and “b” of ten each based on the type of veneering materials used. Veneer discs were fabricated using Ormocer restorative (O) and pressable ceramic (C). Specimens were thermocycled and loaded under universal testing machine for SBS. The statistical analysis was done using one-way ANOVA post hoc Tukey honest significant difference method. Results: A significant difference was observed between the Groups I and II (P < 0.05). The highest mean bond strength when using ormocer veneer was obtained with the Group Ia (19.11 ± 1.92 Mpa) and lowest by Group IIa (8.1 ± 1.04 Mpa), whereas the highest mean bond strength while using ceramic veneer was of similar range for Group Ib (18.04 ± 4.08 Mpa) and Group IIIb (18.07 ± 1.40 Mpa). SEM analysis revealed OF and TE presented mixed type of failure when compared with SA where failure mode was totally adhesive. Conclusion: OF was found equally efficient like TE. Bond strength of ormocer as a veneer was not inferior to ceramic making it one of the promising additions in the field of dentistry.


2016 ◽  
Vol 10 (01) ◽  
pp. 109-115 ◽  
Author(s):  
Mahendran Kavitha ◽  
Sharmila Selvaraj ◽  
Ambica Khetarpal ◽  
Aruna Raj ◽  
Shakunthala Pasupathy ◽  
...  

ABSTRACT Objective: The aim of this study was to investigate the neutralizer effect of antioxidant agents on the bond strength of bleached enamel. Materials and Methods: Sixty enamel slabs were prepared from 60 freshly extracted maxillary central incisors and were divided into six groups. The negative control group received no bleaching treatment and the other groups were bleached with 35% carbamide peroxide (Opalescence Quick; Ultradent, South Jordan, USA). In Group II, composite was built immediately after bleaching and cured without any antioxidants. In Group III, bleached specimens received composite build ups delayed by 1 week. In Groups IV, V, and VI bleached specimens received applications of superoxide dismutase (SOD), sodium ascorbate (SA), and tocopherol solutions, respectively, for 10 min. Following composite bonding, the micro shear bond strength (μSBS) was measured at a speed of 1 mm/min in universal testing machine. Statistical Analysis Used: The μSBS values of all the groups were analyzed using the analysis of variance followed by Tukey honestly significant difference post-hoc test. Results: Bonding of composites to unbleached group (Group I) exhibited the highest mean SBS values and among the antioxidant-treated groups, the highest SBS values were seen with SOD (Group IV) treated samples (23.0040 ± 4.30565 MPa). Conclusions: Application of SA, alpha-tocopherol, and SOD can effectively reverse the bond strength with bleached enamel. SOD gave a comparatively more promising reversal of bond strength than SA and alpha-tocopherol, and deserves further studies.


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