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Adhesives for orthodontic bracket bonding  

Directory of Open Access Journals (Sweden)

Full Text Available The advent of acid etching, introduced by Buonocore in 1955, brought the possibility of bonding between the bracket base and enamel, contributing to more esthetic and conservative orthodontics. This direct bracket bonding technique has brought benefits such as reduced cost and time in performing the treatment, as well as making it easier to perform oral hygiene. The aim of this study was to conduct a survey of published studies on orthodontic bracket bonding to dental enamel. It was verified that resin composites and glass ionomer are the most studied and researched materials for this purpose. Resin-modified glass ionomer, with its biocompatibility, capacity of releasing fluoride and no need for acid etching on the tooth structure, has become increasingly popular among dentists. However, due to the esthetic and mechanical properties of light polymerizable resin composite, it continues to be one of the adhesives of choice in the bracket bonding technique and its use is widely disseminated.

Déborah Daniella Diniz Fonseca

2010-04-01

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Laser debonding of ceramic orthodontic brackets.  

Science.gov (United States)

Laser light energy has been shown in other studies to degrade resins by thermal softening, thermal ablation, or photoablation. If this technology could be successfully applied to bracket debonding, fracturing of both bracket and enamel during debonding might be eliminated. Both polycrystalline alumina and single crystal alumina (sapphire) ceramic orthodontic brackets were bonded to the labial surfaces of lower deciduous bovine incisor teeth with the acid-etch technique as currently practiced in dentistry. Under an externally applied stress of either zero or 0.8 MPa, the brackets were debonded by irradiating the labial surfaces of the brackets with laser light at wavelengths of 248 nm, 308 nm, and 1060 nm, and at light power densities of between about 3 and 33 W/cm2. Debonding times were measured, and the surfaces created by debonding were examined with both light and scanning electron microscopy to determine the extent of bracket and enamel damage. The results showed that under the conditions of this study, no enamel or bracket damage was present in any sample. The polycrystalline brackets debonding times were about 3 seconds, 5 seconds, and 24 seconds for 248 nm, 308 nm, and 1060 nm of radiation, respectively. The debonding of polycrystalline brackets is caused by thermal softening of the bonding resin resulting from heating of the bracket. The hot bracket then slides off the tooth. All sapphire brackets debonded in less than 1 second. At sufficiently high power levels, debonding of sapphire brackets is caused by either thermal ablation or photoablation resulting from direct interaction of the light beam with the resin.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8427220

Tocchio, R M; Williams, P T; Mayer, F J; Standing, K G

1993-02-01

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Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded with Nano-filled Composites  

OpenAIRE

Objectives: The purpose of this study was to evaluate the shear bond strength (SBS) of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Materials and Methods: Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT) was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel...

Mohammad Sadegh Ahmad Akhoundi; Javad Chalipa; Sepideh Arab; Mohammad Javad Kharrazifard; Maryam Ahmadyar

2013-01-01

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Retrieval analysis of different orthodontic brackets: the applicability of electron microprobe techniques for determining material heterogeneities and corrosive potential  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: The objective of this study was to investigate the applicability of micro-analytical methods with high spatial resolution to the characterization of the composition and corrosion behavior of two bracket systems. MATERIAL AND METHODS: The surfaces of six nickel-free brackets and six nickel [...] -containing brackets were examined for signs of corrosion and qualitative surface analysis using an electron probe microanalyzer (EPMA), prior to bonding to patient's tooth surfaces and four months after clinical use. The surfaces were characterized qualitatively by secondary electron (SE) images and back scattered electron (BSE) images in both compositional and topographical mode. Qualitative and quantitative wavelength-dispersive analyses were performed for different elements, and by utilizing qualitative analysis the relative concentration of selected elements was mapped two-dimensionally. The absolute concentration of the elements was determined in specially prepared brackets by quantitative analysis using pure element standards for calibration and calculating correction-factors (ZAF). RESULTS: Clear differences were observed between the different bracket types. The nickel-containing stainless steel brackets consist of two separate pieces joined by a brazing alloy. Compositional analysis revealed two different alloy compositions, and reaction zones on both sides of the brazing alloy. The nickel-free bracket was a single piece with only slight variation in element concentration, but had a significantly rougher surface. After clinical use, no corrosive phenomena were detectable with the methods applied. Traces of intraoral wear at the contact areas between the bracket slot and the arch wire were verified. CONCLUSION: Electron probe microanalysis is a valuable tool for the characterization of element distribution and quantitative analysis for corrosion studies.

Alexandra Ioana, Holst; Stefan, Holst; Ursula, Hirschfelder; Volker Von, Seckendorff.

2012-08-01

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Retrieval analysis of different orthodontic brackets: the applicability of electron microprobe techniques for determining material heterogeneities and corrosive potential  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: The objective of this study was to investigate the applicability of micro-analytical methods with high spatial resolution to the characterization of the composition and corrosion behavior of two bracket systems. MATERIAL AND METHODS: The surfaces of six nickel-free brackets and six nickel-containing brackets were examined for signs of corrosion and qualitative surface analysis using an electron probe microanalyzer (EPMA, prior to bonding to patient's tooth surfaces and four months after clinical use. The surfaces were characterized qualitatively by secondary electron (SE images and back scattered electron (BSE images in both compositional and topographical mode. Qualitative and quantitative wavelength-dispersive analyses were performed for different elements, and by utilizing qualitative analysis the relative concentration of selected elements was mapped two-dimensionally. The absolute concentration of the elements was determined in specially prepared brackets by quantitative analysis using pure element standards for calibration and calculating correction-factors (ZAF. RESULTS: Clear differences were observed between the different bracket types. The nickel-containing stainless steel brackets consist of two separate pieces joined by a brazing alloy. Compositional analysis revealed two different alloy compositions, and reaction zones on both sides of the brazing alloy. The nickel-free bracket was a single piece with only slight variation in element concentration, but had a significantly rougher surface. After clinical use, no corrosive phenomena were detectable with the methods applied. Traces of intraoral wear at the contact areas between the bracket slot and the arch wire were verified. CONCLUSION: Electron probe microanalysis is a valuable tool for the characterization of element distribution and quantitative analysis for corrosion studies.

Alexandra Ioana Holst

2012-08-01

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Effect of different methods of enamel conditioning on bond strength of orthodontic brackets  

OpenAIRE

Background and Aim: With the introduction of different bondable restorative materials in dentistry, various methods have been suggested to enhance the polymerization and shear bond strength of these materials. The aim of this study was to determine the effects of different methods of enamel conditioning on bond strength of orthodontic brackets and on the bracket/ adhesive failure mode. Materials and Methods: In this experimental in vitro study, brackets were bonded to thirty-six bovine inciso...

Ar, Davari; Yassaei S.; Ar, Danesh Kazemi; Mh, Yousefi

2007-01-01

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Shear bond strength of orthodontic brackets bonded with glass ionomer cement  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction. A great number of techniques have been used for bonding orthodontic brackets to the tooth surfaces. Glass ionomer cements are frequently used material for this purpose. The aim of this study was to measure the shear bond strength of orthodontic brackets bonded with glass ionomer cement Ortho Fuji LC and remained adhesive on the enamel surface after brackets debonding. Material and methods. A total of 40 extracted premolars for orthodontic reasons in different gender patients, 10-16 years old, were randomly divided into four groups. Using glass ionomer cement Ortho Fuji LC (Tokyo, Japan stainless steel brackets were bonded to the teeth with the average surface area of the bracket base of 14.7 mm2. The shear bond strengths were measured at a crosshead speed of 1 mm per minute, and the load applied at the time of fracture was recorded using electronic dynamometer. Remained adhesive on the enamel after bracket debonding was evaluated using the adhesive remnant index (ARI. Results. Shear bond strength had the highest value for the group where enamel was etched right before bonding bracket (9.14 MPa, than in the group 2 (7.43 MPa, while in the groups 1 (6.72 MPa and 3 (6.22 MPa, where etching was not performed, bond strength was lower. Conclusion. Shear bond strength of orthodontic brackets bonded with glass ionomer cement Ortho Fuji LC had higher values when the enamel was etched than without etching.

Miti? Vladimir

2009-01-01

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Physical and chemical properties of orthodontic brackets after 12 and 24 months: in situ study  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Objective: The aim of this article was to assess how intraoral biodegradation influenced the surface characteristics and friction levels of metallic brackets used during 12 and 24 months of orthodontic treatment and also to compare the static friction generated in these brackets with four different [...] methods of the ligation of orthodontic wires. Material and Methods: Seventy premolar brackets as received from the manufacturer and 224 brackets that were used in previous orthodontic treatments were evaluated in this experiment. The surface morphology and the composition of the deposits found in the brackets were evaluated with rugosimetry, scanning electron microscopy, and energy dispersive X-ray spectroscopy. Friction was analyzed by applying tensile tests simulating sliding mechanics with a 0.019x0.025" steel wire. The static friction levels produced by the following ligation methods were evaluated: loosely attached steel ligature around all four bracket wings, steel ligature attached to only two wings, conventional elastomeric ligation around all 4 bracket wings, and non-conventional Slide® elastomeric ligature. Results: The results demonstrated the presence of biodegradation effects such as corrosion pits, plastic deformation, cracks, and material deposits. The main chemical elements found on these deposits were Carbon and Oxygen. The maximum friction produced by each ligation method changed according to the time of intraoral use. The steel ligature loosely attached to all four bracket wings produced the lowest friction levels in the new brackets. The conventional elastic ligatures generated the highest friction levels. The metallic brackets underwent significant degradation during orthodontic treatment, showing an increase in surface roughness and the deposit of chemical elements on the surface. Conclusion: The levels of static friction decreased with use. The non-conventional elastic ligatures were the best alternative to reduce friction.

Bernardo de Azevedo Bahia, MENDES; Ricardo Alberto Neto, FERREIRA; Matheus Melo, PITHON; Martinho Campolina Rebello, HORTA; Dauro Douglas, OLIVEIRA.

2014-06-01

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Effect of Lactic Acid Etching on Bonding Effectiveness of Orthodontic Bracket after Water Storage  

OpenAIRE

Objective. To determine the effect of lactic acid at various concentrations on the shear bond strength of orthodontic brackets bonded with the resin adhesive system before and after water storage. Materials and Methods. Hundred extracted human premolars were divided into 5 treatment groups and etched for 30 seconds with one of the following agents: lactic acid solution with (A) 10%, (B) 20%, (C) 30%, and (D) 50%; group E, 37% phosphoric acid (control). Metal brackets were bonded using a Trans...

Alsulaimani, Fahad F.

2014-01-01

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Design of an Orthodontic Torque Simulator for Measurement of Bracket Deformation  

Science.gov (United States)

The design and testing of an orthodontic torque simulator that reproduces the effect of archwire rotation on orthodontic brackets is described. This unique device is capable of simultaneously measuring the deformation and loads applied to an orthodontic bracket due to archwire rotation. Archwire rotation is used by orthodontists to correct the inclination of teeth within the mouth. This orthodontic torque simulator will provide knowledge of the deformation and loads applied to orthodontic bracket that will aide clinicians by describing the effect of archwire rotation on brackets. This will also impact that design on new archwirebracket systems by providing an assessment of performance. Deformation of the orthodontic bracket tie wings is measured using a digital image correlation process to measure elastic and plastic deformation. The magnitude of force and moments applied to the bracket though the archwire is also measured using a six-axis load cell. Initial tests have been performed on two orthodontic brackets of varying geometry to demonstrate the measurement capability of the orthodontic torque simulator. The demonstration experiment shows that a Damon Q bracket had a final plastic deformation after a single loading of 0.022 mm while the Speed bracket deformed 0.071 mm. This indicates that the Speed bracket plastically deforms 3.2 times more than the Damon Q bracket for similar magnitude of applied moment. The demonstration experiment demonstrates that bracket geometry affect the deformation of orthodontic brackets and this difference can be detected using the orthodontic torque simulator.

Melenka, G. W.; Nobes, D. S.; Major, P. W.; Carey, J. P.

2013-12-01

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A comparison of shear bond strength of orthodontic brackets bonded with four different orthodontic adhesives  

Science.gov (United States)

Objectives: The objective of this study is to compare the shear bond strength (SBS) of stainless steel (SS) orthodontic brackets bonded with four different orthodontic adhesives. Materials and Methods: Eighty newly extracted premolars were bonded to 0.022 SS brackets (Ormco, Scafati, Italy) and equally divided into four groups based on adhesive used: (1) Rely-a-Bond (self-cure adhesive, Reliance Orthodontic Product, Inc., Illinois, USA), (2) Transbond XT (light-cure adhesive, 3M Unitek, CA, USA), (3) Transbond Plus (sixth generation self-etch primer, 3M Unitek, CA, USA) with Transbond XT (4) Xeno V (seventh generation self-etch primer, Dentsply, Konstanz, Germany) with Xeno Ortho (light-cure adhesive, Dentsply, Konstanz, Germany) adhesive. Brackets were debonded with a universal testing machine (Model No. 3382 Instron Corp., Canton, Mass, USA). The adhesive remnant index (ARI) was recordedIn addition, the conditioned enamel surfaces were observed under a scanning electron microscope (SEM). Results: Transbond XT (15.49 MPa) attained the highest bond strength. Self-etching adhesives (Xeno V, 13.51 MPa; Transbond Plus, 11.57 MPa) showed clinically acceptable SBS values and almost clean enamel surface after debonding. The analysis of variance (F = 11.85, P < 0.0001) and Chi-square (?2 = 18.16, P < 0.05) tests revealed significant differences among groups. The ARI score of 3 (i.e., All adhesives left on the tooth) to be the most prevalent in Transbond XT (40%), followed by Rely-a-Bond (30%), Transbond Plus with Transbond XT (15%), and Xeno V with Xeno Ortho (10%). Under SEM, enamel surfaces after debonding of the brackets appeared porous when an acid-etching process was performed on the surfaces of Rely-a-Bond and Transbond XT, whereas with self-etching primers enamel presented smooth and almost clean surfaces (Transbond Plus and Xeno V group). Conclusion: All adhesives yielded SBS values higher than the recommended bond strength (5.9-7–8 MPa), Seventh generation self-etching primer Xeno V with Xeno Ortho showed clinically acceptable SBS and the least amount of residual adhesive left on the enamel surface after debonding. PMID:24987660

Sharma, Sudhir; Tandon, Pradeep; Nagar, Amit; Singh, Gyan P; Singh, Alka; Chugh, Vinay K

2014-01-01

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CO2 laser debonding of a ceramic bracket bonded with orthodontic adhesive containing thermal expansion microcapsules.  

Science.gov (United States)

We have been studying an easy bracket debonding method using heating of an orthodontic adhesive containing thermal expansion microcapsules. However, heating with a high-temperature heater brings obvious risks of burns around the oral cavity. Thus, we examined safer and more effective bracket debonding methods. The purpose of this in vitro study was to examine the reduction in debonding strength and the time taken using a bracket bonded with an orthodontic adhesive containing thermal expansion microcapsules and a CO2 laser as the heating method while maintaining safety. Ceramic brackets were bonded to bovine permanent mandibular incisors using bonding materials containing various microcapsule contents (0, 30, and 40 wt%), and the bond strengths were measured after laser irradiation for 4, 5, and 6 s and compared with nonlaser-treated groups. Subsequently, the temperature in the pulp chamber during laser irradiation was measured. After laser irradiation for 5 or 6 s, the bond strengths of the adhesive containing 40 wt% microcapsules were significantly decreased to ?0.40?-?0.48-fold (4.6-5.5 MPa) compared with the nonlaser groups. The mean temperature rise of the pulp chamber was 4.3 °C with laser irradiation for 6 s, which was less than that required to induce pulp damage. Based on these results, we conclude that the combined use of a CO2 laser and an orthodontic adhesive containing thermal expansion microcapsules can be effective and safe for debonding ceramic brackets with less enamel damage or tooth pain. PMID:24220847

Saito, Ayano; Namura, Yasuhiro; Isokawa, Keitaro; Shimizu, Noriyoshi

2015-02-01

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Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded with Nano-filled Composites  

Directory of Open Access Journals (Sweden)

Full Text Available Objectives: The purpose of this study was to evaluate the shear bond strength (SBS of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Materials and Methods: Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel were used in groups II and III respectively. The teeth were stored in distilled water at 37°C for 24 hours, thermocycled in distilled water and debonded with a universal testing machine at a crosshead speed of 1 mm/min. The adhesive remnant index (ARI was also evaluated using a stereomicroscope. Results: AELITE Aesthetic Enamel nano-composite revealed a SBS value of 8.44±2.09 MPa, which was higher than Transbond XT (6.91± 2.13 and Filtek TM Supreme XT (6.04± 2.01. Statistical analysis revealed a significant difference between groups II and III (P 0.05. Evaluation of ARI showed that Transbond XT left fewer adhesive remains on teeth after debonding. Conclusion: Results of this study indicate that the aforementioned nano-composites can be successfully used for bonding orthodontic brackets.

Mohammad Sadegh Ahmad Akhoundi

2013-01-01

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The effect of phosphoric acid application time on the bond strength of orthodontic brackets  

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Full Text Available Aim: The aim of this study was to evaluate the effect of different surface treatment intervals (15, 30 and 45 s of 37% phosphoric acid on the bond strength of orthodontic brackets. Materials and Methods: Seventy extracted premolars, glass ionomer cement Ortho Fuji LC (GC Inc., Tokyo, Japan and a conventional self-curing adhesive, System 1+ (Dentaurum, Inspringen, Germany were used. Results: The obtained results suggested that the strongest bond was accomplished after enamel conditioning for 30 s and the weakest after 45 s treatment. Conclusion: The phosphoric acid application time has an effect on the quality and strength of the enamel - bracket bond.

Miti? Vladimir

2008-01-01

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Stereomicroscope analysis of enamel surface after orthodontic bracket debonding.  

Science.gov (United States)

After orthodontic brackets debonding, the remaining resin has to be removed. The purpose of this study was to determine the most efficient method as well as to introduce a new method of composite removal. The study was carried out on a sample of 30 premolars, extracted for orthodontic purposes. Brackets had been bonded using the Ortho One Bisco composite resin. After the removal of brackets, samples were randomly divided into three groups of ten. Composite remnants in the first group were removed using the Band Driver (KaVo). For the second group, the tungsten carbide bur (Komet) was applied. In the third group, composite remnants were removed manually, using adhesive removing pliers (ORMCO). The samples were analysed using a light-stereomicroscope (Olympus). Photomicrographs were examined and the ARI (Adhesive Remnant Index) was calculated. Post Hoc tests (Scheffe, Tukey) indicated a statistically significant difference between groups 1 and 2 as well as between groups 1 and 3. The tungsten carbide bur was found to be the most efficient instrument for composite remnant removal. PMID:12971175

Miksi?, Martina; Slaj, Mladen; Mestrovi?, Senka

2003-01-01

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Orthodontic Bracket Manufacturing Tolerances and Dimensional Differences between Select Self-Ligating Brackets.  

Science.gov (United States)

In all manufacturing processes there are tolerances; however, orthodontic bracket manufacturers seldom state the slot dimensional tolerances. This experiment develops a novel method of analyzing slot profile dimensions using photographs of the slot. Five points are selected along each wall, and lines are fitted to define a trapezoidal slot shape. This investigation measures slot height at the slot's top and bottom, angles between walls, slot taper, and the linearity of each wall. Slot dimensions for 30 upper right central incisor self-ligating stainless steel brackets from three manufacturers were evaluated. Speed brackets have a slot height 2% smaller than the nominal 0.559?mm size and have a slightly convergent taper. In-Ovation brackets have a divergent taper at an average angle of 1.47 degrees. In-Ovation is closest to the nominal value of slot height at the slot base and has the smallest manufacturing tolerances. Damon Q brackets are the most rectangular in shape, with nearly 90-degree corners between the slot bottom and walls. Damon slot height is on average 3% oversized. PMID:20981299

Major, Thomas W; Carey, Jason P; Nobes, David S; Major, Paul W

2010-01-01

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Orthodontic Bracket Manufacturing Tolerances and Dimensional Differences between Select Self-Ligating Brackets  

Directory of Open Access Journals (Sweden)

Full Text Available In all manufacturing processes there are tolerances; however, orthodontic bracket manufacturers seldom state the slot dimensional tolerances. This experiment develops a novel method of analyzing slot profile dimensions using photographs of the slot. Five points are selected along each wall, and lines are fitted to define a trapezoidal slot shape. This investigation measures slot height at the slot's top and bottom, angles between walls, slot taper, and the linearity of each wall. Slot dimensions for 30 upper right central incisor self-ligating stainless steel brackets from three manufacturers were evaluated. Speed brackets have a slot height 2% smaller than the nominal 0.559?mm size and have a slightly convergent taper. In-Ovation brackets have a divergent taper at an average angle of 1.47 degrees. In-Ovation is closest to the nominal value of slot height at the slot base and has the smallest manufacturing tolerances. Damon Q brackets are the most rectangular in shape, with nearly 90-degree corners between the slot bottom and walls. Damon slot height is on average 3% oversized.

Thomas W. Major

2010-01-01

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Hypersensitivity reactions to orthodontic materials.  

OpenAIRE

Most allergic reactions that may be observed during orthodontic treatment are manifestations of hypersensitivity to potentially allergenic factors of orthodontic materials. These factors basically include the latex material of disposable elastic surgical gloves and of most elastic orthodontic materials and the nickel contained in the alloys of metal orthodontic appliances. Allergic hypersensitivity reactions may involve extra- and intra-oral clinical signs usually including localized manifest...

Synodinos, Philippos N.; Eleni Voulgari; Papagrigorakis, Manolis I.

2005-01-01

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Rebonding of unused brackets with different orthodontic adhesives  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: To compare in vitro shear bond strength (SBS) of different orthodontic adhesives in bonding and repeatedly rebonding metal brackets, and to evaluate the bond failure site with the adhesive remnant index (ARI). METHODS: Specimens consisted of 90 extracted human first premolars, randomly di [...] vided into three groups (n=30). The adhesives Alpha Plast (AP), ConciseTM (CO) and TransbondTM XT (TB) were used in each group. Three SBS tests were performed, i.e., one at T0 (initial) and the other two at T1 and T2 (first and second rebondings, respectively), observing a 24-hour interval. The tests were performed in a Shimadzu AG-I (10kN) SBS testing machine, at a speed of 0.5 mm/min. RESULTS: SBS data were subjected to ANOVA, Tukey's test and Bonferroni test (p

Emigdio Enrique Orellana, Jimenez; Sérgio Paulo, Hilgenberg; Márcia Cristina, Rastelli; Gibson Luiz, Pilatti; Bruno, Orellana; Ulisses, Coelho.

2012-04-01

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Static-dynamic friction transition of FRP esthetic orthodontic wires on various brackets by suspension-type friction test.  

Science.gov (United States)

A new testing apparatus for the measurement of frictional properties was designed and the frictional coefficients were obtained and compared with each other in various combinations of brackets and orthodontic wires, including esthetic fiber-reinforced plastic (FRP) wire that was especially designed and manufactured. Three kinds of wires (stainless steel, nickel-titanium, and FRP) and four brackets (single-crystal alumina, polycrystalline alumina, polycarbonate, and stainless steel) were used. The testing was done under dry and wet conditions. The friction testing equipment was designed to attach the bracket to a C-shaped bar suspended with a variable mass, and sliding along a fixed wire. The transition between static and dynamic friction was measured as a breakaway force, with the use of a universal test machine. In addition to material properties, this testing fixture eliminates geometrical factors, such as the rotational moment at the edge of the bracket slot, deflection of the orthodontic wire, and tension of the ligature wire. Nearly ideal frictional properties between materials are obtained. The frictional properties of FRP wire were similar to those of metal wires on all brackets, except the polycrystalline alumina bracket. The frictional coefficient between the polycrystalline ceramic bracket and FRP wire was larger than that of other combinations. There was little difference in frictional coefficients between dry and wet conditions. PMID:14598404

Suwa, N; Watari, F; Yamagata, S; Iida, J; Kobayashi, M

2003-11-15

21

Prevention of demineralization around orthodontic brackets using two different fluoride varnishes  

Science.gov (United States)

Objective: This in-vitro study was done to evaluate the effects of two different seal materials, Duraflor™ and Enamel Pro® Varnish, on enamel demineralization adjacent to orthodontic fixed appliances. Methods: Seventy-two extracted solid premolars were allocated to three groups as one control and two study groups after brackets were placed and bonded with Transbond™ XT. The control group received no topical fluoride application after bonding, whereas in the study groups two fluoride varnishes, Enamel Pro® Varnish and Duraflor™ were applied on the teeth adjacent to brackets. All specimens were then immersed separately in demineralization solution for 96 hours at constant temperature. Demineralization of the enamel surface was evaluated quantitatively by cross-sectional microhardness testing: indentations were made at the edge of the bracket base (0 ?m) and at 100 and 200 ?m distant from it. In all of these positions, 5 indentations were made at 10, 20, 40, 70 and 90 ?m of depths from the external surface of the enamel. Results: The results revealed that, Enamel Pro® Varnish and Duraflor™ group values are higher than the values of control group at every depth. The differences between the depths showed that the microhardness values decreased significantly when the depth increased. In the control group, more demineralization occurred in every indentation compared to the study group. Conclusion: Duraflor™ and Enamel Pro® Varnish can be considered for use in clinic as an effective method to prevent or reduce demineralization during orthodontic treatment, especially in patients with poor oral hygiene. PMID:23408742

Nalbantgil, Didem; Oztoprak, Mehmet Oguz; Cakan, Derya Germec; Bozkurt, Kemal; Arun, Tulin

2013-01-01

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Coating and Surface Treatments on Orthodontic Metallic Materials  

Directory of Open Access Journals (Sweden)

Full Text Available Metallic biomaterials have been extensively used in orthodontics throughout history. Gold, stainless steel, cobalt-chromium alloys, titanium and its alloys, among other metallic biomaterials, have been part of the orthodontic armamentarium since the twentieth century. Metals and alloys possess outstanding properties and offer numerous possibilities for the fabrication of orthodontic devices such as brackets, wires, bands, ligatures, among others. However, these materials have drawbacks that can present problems for the orthodontist. Poor friction control, allergic reactions, and metal ionic release are some of the most common disadvantages found when using metallic alloys for manufacturing orthodontic appliances. In order to overcome such weaknesses, research has been conducted aiming at different approaches, such as coatings and surface treatments, which have been developed to render these materials more suitable for orthodontic applications. The purpose of this paper is to provide an overview of the coating and surface treatment methods performed on metallic biomaterials used in orthodontics.

Claudia García

2012-12-01

23

A scanning electron microscopic investigation of ceramic orthodontic brackets  

International Nuclear Information System (INIS)

Ceramic brackets were introduced to overcome the esthetic disadvantages of stainless steel brackets. The clinical impression of these brackets is very favorable. However, the sliding mechanics used in the Straightwire (A Company, San Diego, CA, USA) system appear to produce slower tooth movements with ceramic compared to stainless steel brackets. To determine whether this was due to any obvious mechanical problem in the bracket slot, Transcend (Unitek Corporation/3M, Monrovia, CA, USA) ceramic brackets were examined by a scanning electron microscope and compared to stainless steel brackets.Consistently, large surface defects were found in the ceramic bracket slots that were not present in the metal bracket slots. These irregularities could obviously hinder the sliding mechanics of the bracket slot-archwire system and create a greater demand on anchorage. Conversely, the fitting surface of the Transcend ceramic bracket showed extremely smooth surface characteristics, and it would seem advisable for the manufacturers to incorporate this surface within the bracket slot. (author)

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Effect of bonding protocol on shear bond strength of orthodontic brackets: An in vitro study  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this study was to evaluate the shear bond strength of bracket composites as a function of the application of flow adhesive prior to the composite and light curing time. Material and methods: Freshly extracted bovine permanent central incisors (50) were acid etched and divided into four g [...] roups varying the attachment protocol: (1) no adhesive, composite light-cured for 20s; (2) no adhesive, composite light-cured for 40s; (3) application of adhesive, composite light-cured for 20s; and (4) application of adhesive, composite light-cured for 40s. For comparison, a chemically cured system was used accordingly to the manufacturer instructions. The samples were stored in distilled water (37ºC) for 24 hours prior to the shear test (0,75mm/min) and the adhesive remnant index (ARI) was registered for each tooth. Results: The present in vitro findings showed that both variables, application of adhesive and light curing time, influenced the bond strength of orthodontic brackets. Brackets bonded without adhesive present lower resistance to shear forces (p=0.05) than the samples bonded with adhesive. Higher bond strength values were found for longer light curing times, though statistical difference (p=0.05) was only observed between groups (3) and (4). ARI results show lower scores for extended light curing times. Although the variables in this study significantly affect the shear bond strength of orthodontic brackets, all the experimental groups show bond strength values greater than the normally accepted in the current literature.

Tais, Munhoz.

2014-09-01

25

A study of frictional forces between orthodontic brackets and archwires.  

Science.gov (United States)

The differences in magnitude of static and kinetic frictional forces generated by 0.022 x 0.030-inch stainless steel (Dentaurum) and polycrystalline ceramic (Transcend) brackets in combination with archwires of different sizes (0.018 inch and 0.019 x 0.025 inch) and materials (stainless steel, nickel-titanium, and beta-titanium) at a constant ligature force were investigated. A friction-testing assembly using the Instron machine was used. In all cases, the static frictional force was greater than the kinetic frictional force. There were no significant differences in the frictional forces generated by stainless steel and polycrystalline ceramic brackets. Beta-titanium archwires produced greater frictional forces than the other two materials. Increasing the archwire diameter increased the frictional force. PMID:7857894

Downing, A; McCabe, J; Gordon, P

1994-11-01

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Trial production of titanium orthodontic brackets fabricated by metal injection molding (MIM) with sintering.  

Science.gov (United States)

Safety and esthetics are two indispensable factors to consider when fabricating orthodontic brackets. However, these factors are not easily achieved when conventional techniques (including forging and casting) are used in the mass production of titanium brackets, albeit the brackets exhibit excellent biocompatibility. In the present study, orthodontic brackets were manufactured by metal powder injection molding with sintering. Brackets with three different base designs were made and subjected to compression shear tests for evaluation of their bonding strength to enamel substrate. The shapes given to the dimple of the base were spherical, oval, and grooved. The maximum shear forces for each type were 11.1 kgf, 7.6 kgf, and 18.5 kgf, respectively. The bonding strengths of the titanium bracket were equivalent to those obtained with conventional stainless steel brackets. Moreover, uniform distribution of Vickers hardness values (average, 240 +/- 40 Hv) measured at three locations indicated that the titanium bracket was uniformly sintered. Accordingly, titanium brackets thus fabricated exhibit a potential for clinical application. PMID:8876601

Deguchi, T; Ito, M; Obata, A; Koh, Y; Yamagishi, T; Oshida, Y

1996-07-01

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Evaluation of shear bond strength of orthodontic resin and resin modified glass ionomer cement on bonding of metal and ceramic brackets  

OpenAIRE

Objective: The aim of this study was to evaluate the shear bond strength of orthodontic resin and resin-modified glass ionomer cement on bonding of metal and ceramic brackets. Material and methods: Forty bovine teeth were sectioned and embedded into PVC with chemically-cured acrylic resin. The labial surfaces were flattened and received prophylaxis with pumice and water. Then they were divided into four groups, according to the bonding material and the type of bracket. Group 1: metallic brac...

Rosana Costa Casanovas de Carvalho; Natália Maria Porto de Carvalho; Synara Santos Herênio; José Roberto de Oliveira Bauer; Antonio Ernandes Macedo Paiva; José Ferreira Costa; Elizabeth Lima Costa

2012-01-01

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Spectrophotometric evaluation of dental bleaching under orthodontic bracket in enamel and dentin  

OpenAIRE

Aware of the diffusion capacity of bleaching in the dental tissues, many orthodontists are subjecting their patients to dental bleaching during orthodontic treatment for esthetic purposes or to anticipate the exchange of esthetic restorations after the orthodontic treatment. For this purpose specific products have been developed in pre-loaded whitening trays designed to fit over and around brackets and wires, with clinical efficacy proven. Objective: The objective of this study was to evaluat...

Lunardi, Nadia; Correr, Americo-bortolazzo; Rastelli, Alessandra-nara-souza; Lima, De?bora-alves-nunes-leite; Consani, Rafael-leonardo-xediek

2014-01-01

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Shear bond strength comparison between direct and indirect bonded orthodontic brackets.  

Science.gov (United States)

The purpose of this study was to compare the shear bond strength of orthodontic brackets bonded to teeth with either an indirect bonding technique and a new adhesive resin or a direct bonding technique and a light-activated adhesive. Fifty-four extracted premolars were mounted in acrylic blocks and randomly divided into 2 groups (n = 27). In one group, orthodontic brackets were bonded to premolars with an indirect bonding adhesive system; in the other, brackets were bonded with the direct method. Seventy-two hours later, the brackets were placed in a testing machine and subjected to a shear force with a crosshead speed of 1 mm/minute. The mean shear bond strengths for the indirect and direct groups were 11.2 and 10.9 MPa, respectively, both exceeding the minimum shear bond strength range of 5.9 to 7.8 MPa often cited in the literature for clinical success. Data were analyzed with Student t tests. No significant difference in shear bond strength between the 2 groups was detected (P =.76). Resin remnants on orthodontic bracket pads were observed with a dissecting microscope at 30x magnification and scored with a modified adhesive remnant index. There was no significant difference between groups (P >.05). There was also no correlation between shear bond strength and the percentage of adhesive resin remnants left on the orthodontic bracket. Under the conditions of this study, no evidence suggests a difference in shear bond strength of orthodontic brackets bonded to tooth enamel, whether they are bonded with the direct or indirect technique. PMID:14614426

Yi, Gia K; Dunn, William J; Taloumis, Louis J

2003-11-01

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Evaluation of shear bond strength of orthodontic resin and resin modified glass ionomer cement on bonding of metal and ceramic brackets  

Directory of Open Access Journals (Sweden)

Full Text Available Objective: The aim of this study was to evaluate the shear bond strength of orthodontic resin and resin-modified glass ionomer cement on bonding of metal and ceramic brackets. Material and methods: Forty bovine teeth were sectioned and embedded into PVC with chemically-cured acrylic resin. The labial surfaces were flattened and received prophylaxis with pumice and water. Then they were divided into four groups, according to the bonding material and the type of bracket. Group 1: metallic bracket + Transbond XT; Group 2: metallic bracket + Vitremer; Group 3: ceramic bracket + Transbond XT; Group 4: ceramic bracket + Vitremer. The bonding was performed according to the manufacturers’ recommendations. The shear bond strength test was conducted in a universal testing machine (TIRAtest 2420 at a crosshead speed of 0.5 mm/min. Then, the fractured surfaces were evaluated using a stereomicroscope (x15 magnification to check the adhesive remnant index. Data was subjected to two-way ANOVA and Tukey’s test for pairwise comparisons (? = 0.05. Results: The results suggested a non-significant effect of the interaction (p > 0.97, and only main factors were significant (p = 0.0001. The bond strength of Transbond XT was statistically higher than Vitremer. Ceramic brackets obtained the highest values of resistance when compared with metal brackets. Conclusion: The ceramic brackets bonded with Transbond XT orthodontic resin have excellent bond strength results.

Rosana Costa Casanovas de Carvalho

2012-06-01

31

Electron microscopy analysis of different orthodontic brackets and their adhesion to the tooth enamel.  

Science.gov (United States)

This study proposed to evaluate the surface morphology of different types of orthodontic brackets and the characteristics of their adhesion to the tooth enamel. There have been taken into study six metallic, five ceramic and one polymeric bracket from different brands (Ormco, Lancer, Leone, Damon, 3M, Ultradent, American Orthodontics, Rocky Mountain). The surface base of the each bracket it have been ESEM analyzed using scanning electron microscope Phillips XL-30 ESEM. There have been investigated several parameters that have a potential influence of the bracket-bonding agent interface joint: chemical composition, roughness, surface morphology and wideness. After ESEM analysis, the same metallic and ceramic brackets have been afterwards collated on extracted teeth and subjected to mechanical tests. After the mechanical testing, the samples were once again ESEM investigated. All fractures occurred in the area of the adhesive system, recording adhesive fractures of the tooth-composite resin and composite-bracket, cohesive fractures and both. The metallic brackets surfaces that are optima for a good adhesion is that of a mesh sand blasted and acid etched. From the esthetic brackets, the ceramic ones are superior to polymeric ones regarding bonding to teeth. PMID:25178330

Ciocan, Delia Ioana; Stanciu, Drago?; Popescu, Manuela Anca; Miculescu, Florin; Plotog, Ioan; V?rzaru, Gauden?iu; Ciocan, Lucian Toma

2014-01-01

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Orthodontic brackets in high field MR imaging: experimental evaluation of magnetic field interactions at 3.0 tesla  

International Nuclear Information System (INIS)

Purpose: To evaluate static magnetic field interactions for 32 commonly used orthodontic brackets in a 3.0 T magnetic resonance imaging (MRI) system. Materials and methods: 32 orthodontic brackets consisting of a steel alloy (n=27), a cobalt-chromium alloy (n=2), ceramic (n=1), ceramic with a steel slot (n=1), and titanium (n=1) from 13 different manufacturers were tested for magnetic field interactions in a static magnetic field at 3.0 T (Gyroscan Intera 3.0 T, Philips Medical Systems, Best, Netherlands). The magnetic deflection force FZ [mN] was evaluated by determining the deflection angle ?[ ] using the established deflection angle test according to the ASTM guidelines. The magnetic-field-induced rotational force Frot or torque was qualitatively determined using a 5-point grading scale (0: no torque; +4: very strong torque). Results: In 18 of the 32 brackets, the deflection angle ? was found to be > 45 and the translational force exceeded the gravitational force FG on the particular bracket (FZ: 1.2-45.7 mN). The translational force FZ was found to be up to 68.5 times greater than the gravitational force FG (FZ/FG: 1.4-68.5). The rotational force Frot was correspondingly high (+3/+4) for those brackets. For the remaining 14 objects, the deflection angles were < 45 and the torque measurements ranged from 0 to +2. The static magnetic field did not affect the titaniumgnetic field did not affect the titanium bracket and the ceramic bracket. No measurable translational and rotational forces were found. (orig.)

33

Hypersensitivity reactions to orthodontic materials.  

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Full Text Available Most allergic reactions that may be observed during orthodontic treatment are manifestations of hypersensitivity to potentially allergenic factors of orthodontic materials. These factors basically include the latex material of disposable elastic surgical gloves and of most elastic orthodontic materials and the nickel contained in the alloys of metal orthodontic appliances. Allergic hypersensitivity reactions may involve extra- and intra-oral clinical signs usually including localized manifestations, at the site of contact with the allergen, such as erythema, edema, itching of the skin or oral mucosa and more rarely systemic manifestations, such as generalized rash and dyspnea, whereas in extreme situations aphylactic reaction may be observed. In any case, when taking the patient’s medical history, it is necessary to record in detail all previous allergic episodes of any type. Where considered necessary, the diagnosis of hypersensitivity to specific materials is documented by the allergiologist following specialized dermatological or hematological tests. Although the phenomenon of hypersensitivity to orthodontic materials is not common in routine clinical practice, in cases where an allergic reaction is observed, the prompt diagnosis is of utmost importance, and it should be followed by the immediate interruption of exposure to the allergen along with the substitution of any suspected /potent allergens or/and modification of treatment planning. The aim of this review is to describe, on the basis of modern literature, the latest evidence-based scientific data concerning etiology, diagnosis and treatment of allergic reactions to materials most frequently used during orthodontic treatment.

Philippos N. Synodinos

2005-01-01

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Biodegradação de braquetes ortodônticos: avaliação da liberação iônica in vitro / Biodegradation of orthodontic brackets: in vitro ion release  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: avaliar, in vitro, a biodegradação de aparelhos ortodônticos simulados constituídos de braquetes e fios de aço inoxidável. METODOLOGIA: a amostra foi dividida em 2 grupos, de acordo com a marca dos braquetes usados: grupo A - Dyna-Lock, 3M/Unitek (AISI 303); e grupo B - LG Edgewise Standar [...] d, American Orthodontics (AISI 316L). Os corpos-de-prova permaneceram incubados em solução salina (0,05%) a 36ºC, sob agitação por um período de até 60 dias. A análise da liberação iônica foi realizada por meio de espectrofotometria de absorção atômica. O peso em massa dos braquetes também foi medido antes e após o experimento. RESULTADOS: os resultados indicaram que o grupo A apresentou maior liberação de íons ferro, níquel e cromo do que o grupo B. Além disso, os braquetes do grupo A também mostraram perda de massa, considerada outro indicativo de corrosão. CONCLUSÃO: concluiu-se que, nas condições deste experimento, os braquetes do grupo A apresentaram maior biodegradação que os acessórios do grupo B, o que pode estar associado à liga metálica e/ou ao processo de fabricação dos mesmos. Abstract in english OBJECTIVE: The purpose of this study was to evaluate, in vitro, the biodegradation of simulated orthodontic appliances consisting of stainless steel brackets and wires. MATERIALS AND METHODOS: The sample was divided in 2 groups, according to brackets brand: group A - Dyna-Lock, 3M/ Unitek (AISI 303) [...] ; and group B - LG Edgewise Standard, American Orthodontics (AISI 316L). The specimens (simulated orthodontic appliances) were incubated in saline solution (0.05%), in shake, at 36ºC, for 60 days. The ion release was detected by atomic absorption spectrophotometer. The weight of brackets was also measured before and after the test. RESULTS: The results indicated that group A released more ions iron, nickel and chromium than group B. Moreover, the brackets in group A also presented weight loss, which is considered an indicator of corrosion. CONCLUSION: It was concluded that, under the present study conditions, the brackets from group A presented a higher biodegradation than group’s B brackets, what could be associated to composition and manufacturing process of these brackets.

Gabriel Schmidt, Dolci; Luciane Macedo de, Menezes; Rodrigo Matos de, Souza; Berenice Anina, Dedavid.

2008-06-01

35

Biodegradação de braquetes ortodônticos: avaliação da liberação iônica in vitro Biodegradation of orthodontic brackets: in vitro ion release  

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: avaliar, in vitro, a biodegradação de aparelhos ortodônticos simulados constituídos de braquetes e fios de aço inoxidável. METODOLOGIA: a amostra foi dividida em 2 grupos, de acordo com a marca dos braquetes usados: grupo A - Dyna-Lock, 3M/Unitek (AISI 303; e grupo B - LG Edgewise Standard, American Orthodontics (AISI 316L. Os corpos-de-prova permaneceram incubados em solução salina (0,05% a 36ºC, sob agitação por um período de até 60 dias. A análise da liberação iônica foi realizada por meio de espectrofotometria de absorção atômica. O peso em massa dos braquetes também foi medido antes e após o experimento. RESULTADOS: os resultados indicaram que o grupo A apresentou maior liberação de íons ferro, níquel e cromo do que o grupo B. Além disso, os braquetes do grupo A também mostraram perda de massa, considerada outro indicativo de corrosão. CONCLUSÃO: concluiu-se que, nas condições deste experimento, os braquetes do grupo A apresentaram maior biodegradação que os acessórios do grupo B, o que pode estar associado à liga metálica e/ou ao processo de fabricação dos mesmos.OBJECTIVE: The purpose of this study was to evaluate, in vitro, the biodegradation of simulated orthodontic appliances consisting of stainless steel brackets and wires. MATERIALS AND METHODOS: The sample was divided in 2 groups, according to brackets brand: group A - Dyna-Lock, 3M/ Unitek (AISI 303; and group B - LG Edgewise Standard, American Orthodontics (AISI 316L. The specimens (simulated orthodontic appliances were incubated in saline solution (0.05%, in shake, at 36ºC, for 60 days. The ion release was detected by atomic absorption spectrophotometer. The weight of brackets was also measured before and after the test. RESULTS: The results indicated that group A released more ions iron, nickel and chromium than group B. Moreover, the brackets in group A also presented weight loss, which is considered an indicator of corrosion. CONCLUSION: It was concluded that, under the present study conditions, the brackets from group A presented a higher biodegradation than group’s B brackets, what could be associated to composition and manufacturing process of these brackets.

Gabriel Schmidt Dolci

2008-06-01

36

Influence of surface treatments on the shear bond strength of orthodontic brackets to porcelain  

Science.gov (United States)

The purpose of this study was to investigate the effect of various surface treatments after different storage time and thermocycling on the shear bond strength of orthodontic brackets to the feldspathic porcelain surfaces. 128 disc-shaped porcelain specimens were randomly assigned to the following surface treatments: 9.6% HFA, 9.6% HFA combined with silane, 50 ? aluminum trioxide sandblasting followed by silane and application of silane after 37% phosphoric acid. Metal or ceramic brackets were bonded onto each treated porcelain facet with light cured resin. The samples were stored in 37 °C water 1 day or 7 days, thermocycled 500 times from 5 to 55 °C. The shear bond strengths were measured (1 mm/min), and statistically analyzed. The bond failure sites were classified according to ARI system. The surface of the glazed, sandblasted, hydrofluoric and phosphoric acid etched porcelain were examined with SEM. All groups achieved reasonable bond strengths to withstand the application of orthodontic forces. Water storage for 7 days caused lower shear bond strength than that of 1 day. But there is no statistically significant difference between the two groups. The mean shear bond strength provided by ceramic bracket with mechanical retention had no statistical difference with that of metal bracket. Therefore, the optimal treatment for orthodontic brackets bonding to feldspathic porcelain was to apply phosphoric acid combined with silane.

Wang, Cong; Zeng, Jishan; Wang, Shaoan; Yang, Zheng; Huang, Qian; Chen, Pixiu; Zhou, Shujuan; Liu, Xiaoqing

2008-11-01

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In vitro evaluation of corrosion and cytotoxicity of orthodontic brackets.  

Science.gov (United States)

The corrosion resistance of AISI 304 stainless steel (AISI 304 SS) and manganese stainless steel (low-nickel SS) brackets in artificial saliva was investigated. The cytotoxic effects of their corrosion products on L929 cell culture were compared by two assays, crystal violet, to evaluate cell viability, and MTT (3-[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide), for cell metabolism and proliferation. The atomic absorption spectroscopic analysis of the corrosion products demonstrated that nickel and manganese ion concentrations were higher for the AISI 304 SS-bracket immersion solution as compared with the low-nickel SS brackets. Scanning electron microscopy and energy-dispersive spectroscopy demonstrated less corrosion resistance for the AISI 304 SS brackets. Although none of the bracket extracts altered L929 cell viability or morphology, the AISI 304 SS-bracket extracts decreased cellular metabolism slightly. The results indicated that the low-nickel SS presents better in vitro biocompatibility than AISI 304 SS brackets. Abbreviations used: AISI, American Iron and Steel Institute; EDS, energy-dispersive spectroscopy; OD, optical density; ISO, International Organization for Standardization; MTT, (3-{4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; NiSO(4), nickel sulfate; SEM, standard error of the mean; WHO, World Health Organization; and TNF, tumor necrosis factor. PMID:17452565

Costa, M T; Lenza, M A; Gosch, C S; Costa, I; Ribeiro-Dias, F

2007-05-01

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The tensile bond strength of new and rebonded stainless steel orthodontic brackets.  

Science.gov (United States)

The study investigated the effect on the tensile/peel bond strength of the variables associated with the bracket base, the enamel surface, and the type of adhesive when both new and used brackets were rebonded to a previously bonded enamel surface. The tensile/peel bond strength was firstly evaluated for three different types of stainless steel orthodontic bracket/base combinations. The cast integral base gave a significantly lower bond strength than the foil-mesh and photo-etched bases. Following debonding, a group of new brackets were bonded to the teeth using a chemically-activated or a light-cured adhesive. The old adhesive had been removed from the enamel by either a hand scaler or a tungsten-carbide bur. The rebonded new brackets demonstrated a small, but statistically significant fall in bond strength. No differences were found between the enamel preparations or the adhesives. A further group of previously debonded brackets were rebonded to the same teeth. The bracket bases were prepared by either smoothing with a green stone or heating in a bunsen flame followed by sandblasting and electropolishing. Highly significant falls in bond strength were obtained with all the bases. No significant differences were found between the two methods of bracket preparation. PMID:8500538

Regan, D; LeMasney, B; van Noort, R

1993-04-01

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Effectiveness of varnish with CPP-ACP in prevention of caries lesions around orthodontic brackets: an OCT evaluation.  

Science.gov (United States)

Summary OBJECTIVE: To evaluate the in vitro efficiency of applying varnish containing casein phosphopeptide (CPP) and amorphous calcium phosphate (ACP) in prevention of caries lesions around orthodontic brackets. PMID:24997026

Pithon, Matheus M; Dos Santos, Mariana J; Andrade, Camilla S S; Leão Filho, Jorge César B; Braz, Ana Karla S; de Araujo, Renato E; Tanaka, Orlando M; Fidalgo, Tatiana K S; Dos Santos, Adrielle M; Maia, Lucianne C

2014-07-01

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Enamel Surface Roughness after Debonding of Orthodontic Brackets and Various Clean-Up Techniques  

Science.gov (United States)

Objective: This study aimed to evaluate enamel roughness after adhesive removal using different burs and an Er:YAG laser. Materials and Methods: The buccal surfaces of forty human premolars were sealed by two layers of nail varnish, except for a circular area of 3 mm in diameter on the middle third. The enamel surfaces were initially subjected to profilometry analysis and four parameters of surface irregularity (Ra, Rq, Rt and Rz) were recorded. Following bracket bonding and debonding, adhesive remnants were removed by tungsten carbide burs in low- or high- speed handpieces (group 1 and 2, respectively), an ultrafine diamond bur (group 3) or an Er:YAG laser (250 mJ, long pulse, 4 Hz) (group 4), and surface roughness parameters were measured again. Then, the buccal surfaces were polished and the third profilometry measurements were performed. Results: The specimens that were cleaned with a low speed tungsten carbide bur showed no significant difference in surface irregularity between the different treatment stages (p>0.05). Surface roughness increased significantly after clean-up with the diamond bur and the Er:YAG laser (p<0.01). In comparison between groups, adhesive removal with tungsten carbide burs at slow- or high-speed handpieces produced the lowest, while enamel clean-up with the Er:YAG laser caused the highest values of roughness measurements (P<0.05). Conclusion: Under the study conditions, application of the ultrafine diamond bur or the Er:YAG laser caused irreversible enamel damage on tooth surface, and thus these methods could not be recommended for removing adhesive remnants after debonding of orthodontic brackets. PMID:23724206

Ahrari, Farzaneh; Akbari, Majid; Akbari, Javad; Dabiri, Ghahraman

2013-01-01

41

Enamel Surface Roughness after Debonding of Orthodontic Brackets and Various Clean-Up Techniques  

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Full Text Available Objective: This study aimed to evaluate enamel roughness after adhesive removal using different burs and an Er:YAG laser.Materials and Methods: The buccal surfaces of forty human premolars were sealed by two layers of nail varnish, except for a circular area of 3 mm in diameter on the middle third. The enamel surfaces were initially subjected to profilometry analysis and four parameters of surface irregularity (Ra, Rq, Rt and Rz were recorded. Following bracket bonding and debonding, adhesive remnants were removed by tungsten carbide burs in low- or high- speed handpieces (group 1 and 2, respectively, an ultrafine diamond bur (group 3 or an Er:YAG laser (250 mJ, long pulse, 4 Hz (group 4, and surface roughness parameters were measured again. Then, the buccal surfaces were polished and the third profilometry measurements were performed.Results: The specimens that were cleaned with a low speed tungsten carbide bur showed no significant difference in surface irregularity between the different treatment stages (p>0.05. Surface roughness increased significantly after clean-up with the diamond bur and the Er:YAG laser (p<0.01. In comparison between groups, adhesive removal with tungsten carbide burs at slow- or high-speed handpieces produced the lowest, while enamel clean-up with the Er:YAG laser caused the highest values of roughness measurements (P<0.05.Conclusion: Under the study conditions, application of the ultrafine diamond bur or the Er:YAG laser caused irreversible enamel damage on tooth surface, and thus these methods could not be recommended for removing adhesive remnants after debonding of orthodontic brackets.

Farzaneh Ahrari

2013-01-01

42

Evaluation of acquired acid resistance of enamel surrounding orthodontic brackets irradiated by laser and fluoride application.  

Science.gov (United States)

Demineralization of enamel around orthodontic brackets is a clinical problem which can lead to some esthetic concerns like white spot lesions. The aim of this in vitro study was to evaluate the effect of the Er, Cr:YSGG laser and fluoride application on the acid resistance of enamel adjacent to orthodontic brackets. A total of 60 healthy, permanent, human premolars were selected and bonded with brackets, then they were randomly assigned to four groups (n?=?15): topical APF gel (1.23% F, pH 3.5, for 4 min); Er,Cr:YSGG laser (P:0.25 W, E:12.5 mJ, RR:20 Hz, PD:140 ?s, 11% air, without water, for 10 s); fluoride + laser group (F + L), and control group (C). All specimens were demineralized for 10 days in a 0.2 M acetate buffer solution, and the calcium content were subsequently determined with atomic absorption spectrometry. There were significant differences between the calcium content of F + L and F group in comparison to control group. The least concentration of calcium was seen in F + L group, and the most value was observed in C group. Combination of Er, Cr:YSGG laser with fluoride and fluoride alone decreased enamel solubility significantly more than laser alone. In addition, combination of laser and fluoride leads to less consumption of fluoride amount. And patients can use it at the beginning of treatment instead of daily use of fluoride. So we suggest using it in preventing enamel demineralization around orthodontic brackets. PMID:23624699

Fekrazad, Reza; Ebrahimpour, Leila

2014-11-01

43

Microhardness of enamel adjacent to orthodontic brackets after CO2 laser irradiation and fluoride application.  

Science.gov (United States)

This study evaluated the effectiveness of carbon dioxide (CO2) laser combined or not with fluoride application on the surface microhardness of enamel adjacent to orthodontic brackets. Fifteen human molars were selected from which 30 enamel fragments measuring 4 mm2 were obtained. The fragments were embedded in PCV tubes with acrylic resin and prepared using water abrasive paper, felt disks and alumina. Orthodontic brackets cut in half were bonded to enamel and 3 microhardness readings were performed on the adjacent surface, as follows: initial, after cariogenic challenge and final. The specimens were divided into the following 3 groups (n=10): Group C: control, Group L: irradiated with CO2 laser, and Group FL: topical fluoride application and CO2 laser irradiation. After initial reading, the specimens were placed in a demineralizing solution for 32 h and the second reading was to verify if demineralization was uniform in all groups. After the treatments, the specimens were submitted to DES-RE cycling for 8 days followed by final surface microhardness reading. The data were analyzed statistically using ANOVA and Duncan test (?=0.05). At the final measurement Group FL obtained higher microhardness value than Groups C and L (ptopical fluoride application was effective to increase the surface microhardness of enamel. PMID:24474294

Stangler, Leonardo Pucci; Romano, Fábio Lourenço; Shirozaki, Mariana Umekita; Galo, Rodrigo; Afonso, Alessandra Marques Correa; Borsatto, Maria Cristina; Matsumoto, Mírian Aiko Nakane

2013-01-01

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Effect of toothbrushing with different manual toothbrushes on the shear bond strength of orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this study was to evaluate the effect of brushing with a Colgate 360º or Oral B Indicator 35 toothbrush on the shear bond strength of orthodontic brackets bonded to extracted human teeth. The bristle wear and bristle tip morphology were also examined after simulated tooth-brushing. Orthod [...] ontic brackets (Roth-P/1st and 2nd premolar S/D- Slot 0.18") were bonded (Transbond XT®) to the smoothest surface of each of 45 extracted human molar and premolar teeth. Test specimens were randomly divided into three groups: Group 1, control group with no brushing; Group 2, brushing with the Oral B Indicator 35; Group 3, brushing with the Colgate 360º. Samples were adapted to a machine that simulated tooth-brushing. The bond strength of each bracket to each tooth was assessed with a mechanical testing machine. The bristle wear and bristle tip morphology indices were also assessed. Statistically significant differences were defined for p

Guilherme José Pimentel Lopes de, Oliveira; Chaine, Pavone; Maurício Ribeiro, Costa; Rosemary Adriana Chiérici, Marcantonio.

2010-09-01

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Friction between different wire bracket combinations in artificial saliva: an in vitro evaluation  

OpenAIRE

OBJECTIVE: The objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment. MATERIAL AND METHODS: Stainless steel (SS) and titanium-molybdenum alloy (TMA) wires of 0.019x0.025-in diameter (American Orthodontics) and polycarbonate bracket (American Orthodontics), ceramic bracket (American Orthodontics), and metal bracket (3M Unitek) with slots of 0.022x0.030-in were used. The friction coefficient ...

Tatiana Kelly da Silva Fidalgo; Matheus Melo Pithon; José Vinicius Bolognesi Maciel; Ana Maria Bolognese

2011-01-01

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Comparison of shear bond strength of orthodontics brackets on composite resin restorations with different surface treatments  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese INTRODUÇÃO: frequentemente, os pacientes ortodônticos apresentam restaurações de resina composta; no entanto, existem poucos estudos que avaliam a melhor forma de colagem ortodôntica nessa situação. OBJETIVO: o objetivo do presente trabalho foi avaliar a força adesiva de braquetes ortodônticos em re [...] staurações resinosas com tratamento de superfície. MÉTODOS: foram utilizados 51 incisivos inferiores bovinos divididos aleatoriamente em três grupos. No grupo controle (GC), os braquetes foram colados em esmalte dentário; nos grupos experimentais com tratamento (GCT) e sem tratamento (GST), os braquetes foram colados em restauração de resina previamente realizada, diferenciando-se pelo tratamento de superfície com broca diamantada. Os dentes foram incluídos em tubos de PVC com resina acrílica autopolimerizável. O ensaio de cisalhamento foi executado em máquina universal de ensaios Emic. Os grupos foram submetidos à ANOVA com pós-teste de Tukey para verificação da diferença estatística entre os grupos (? = 0,05). RESULTADOS: GC (6,62MPa) e GCT (6,82MPa) apresentaram resultados semelhantes, enquanto o GST (5,07MPa) obteve resultados estatisticamente menores (p Abstract in english INTRODUCTION: Orthodontic patients frequently present composite resin restorations, however there are few studies that evaluate the best way for orthodontic bonding in this situation. OBJECTIVE: The objective of this work was to evaluate the bond strength of orthodontic brackets in resin restoration [...] s with surface treatment. METHODS: Fifty one bovine lower incisors were randomly divided into three groups. On the control group (CG) the brackets were bonded to dental enamel; on experimental groups, brackets were bonded to resin restoration with diamond drill treatment (EGT) and with no treatment (EGN). The teeth were placed in PVC tubes with autopolymerized acrylic resin. The shear test was performed in EMIC universal testing machine. The groups were submitted to ANOVA analysis of variance with Tukey post test to verify the statistical difference between groups (? = 0.05). RESULTS: CG (6.62 MPa) and EGT (6.82 MPa) groups presented similar results, while EGN (5.07 MPa) obtained statistically lower results (p

Alexandre Antonio, Ribeiro; Ariane Vicente de, Morais; Daniel Paludo, Brunetto; Antonio Carlos de Oliveira, Ruellas; Monica Tirre Souza de, Araujo.

2013-08-01

47

A Comparison of the Shear Bond Strength of Orthodontic Brackets Bonded With Light-Emitting Diode and Halogen Light-Curing Units  

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Full Text Available Statement of the problem: Various methods such as light emitting diode (LED have been used to enhance the polymerization of resin-based orthodontic adhesives. There is a lack of information on the advantages and disadvantages of different light curing systems.Purpose: The aim of this study was to compare the effect of LED and halogen light curing systems on the shear bond strength of orthodontic brackets.Materials and Methods: Forty extracted human premolars were etched with 37% phosphoric acid and cleansed with water spray and air dried. The sealant was applied on the tooth surface and the brackets were bonded using Transbond adhesive (3M Unitek,Monrovia, Calif. Adhesives were cured for 40 and 20 seconds with halogen (Blue Light, APOZA, Taiwan and LED (Blue dent, Smart, Yugoslavia light-curing systems,respectively. Specimens were thermocycled 2500 times (from 5 to 55 °C and the shear bond strength of the adhesive system was evaluated with an Universal testing machine (Zwick GmbH, Ulm, Germany at a crosshead speed of 1 mm/min until the bracketswere detached from the tooth. Adhesive remnant index (ARI scores were determined after bracket failure. The data were submitted to statistical analysis, using Mann-Whitney analysis and t-test.Results: No significant difference was found in bond strength between the LED and halogen groups (P=0.12. A significant difference was not observed in the adhesive remnant index scores between the two groups (P=0.97.Conclusion: Within the limitations of this in vitro study, the shear bond strength of resin-based orthodontic adhesives cured with a LED was statistically equivalent to those cured with a conventional halogen-based unit. LED light-curing units can be suggested for the polymerization of orthodontic bonding adhesives.

SM. Abtahi

2006-09-01

48

Effect of Fast Curing Lights, Argon Laser, and Plasma Arc on Bond Strengths of Orthodontic Brackets: An In Vitro Study  

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Full Text Available Objective: Nowadays light-cured composites are used widely by orthodontists to bond brackets. As these composites require 20-40 seconds time per tooth to be light cured, more chair-time in needed compared to self-cured composites. In recent years, the argon laser and plasma arc lights have been introduced in dentistry to reduce this curing time. The purpose of this study was to compare bond strength of brackets bonded with the argon la-ser and plasma arc light with those bonded with the conventional halogen light.Materials and Methods: Fifty-one intact human premolars were randomly divided into three groups of 17 teeth each. Stainless steel twin premolar brackets (018- in Dyna lock, 3M Unitek were bonded to the teeth using one of these curing devices in each group: the halogen unit (Coltolux 75, Switzerland, the argon laser unit (Bo-5, Iran , and the plasma arc unit (Remecure 15, Belgium. The orthodontic adhesive was the same in the three groups (Transbond XT, 3M Unitek. After thermal cycling, the diametral tensilebond strength of specimens was measured using a debonding plier in a Zwick Universal Testing machine (Z/100, Germany.Results: The mean bond strengths was 17.344 MPa (SD=4.567 for halogen 19.172 MPa(SD=6.328 for laser and 19.322 MPa (SD=4.036 for plasma arc groups. No statistically significant difference existed in the mean bond strengths among three groups.Conclusion: Argon laser lights, significantly reducing the curing time of orthodonticbrackets without affecting bond strength, have the potential to be considered as advanta-geous alternatives to conventional halogen light.

M. Hashem-Hoseini

2008-12-01

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Bonding Orthodontic Ceramic Brackets to Ceramic Restorations: Evaluation of Different Surface Conditioning Methods  

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Full Text Available The purpose of this study was to compare the shear bond strength and Adhesive Remnant Index of four different veneering ceramic materials to ceramic brackets. Additionallly, a further aim of this study was to overcome the etching using hydrofluoric acid which is noxious and could seriously damage the corneas of the eyes. Two surface conditioning methods of four ceramic materials before bonding brackets were examined: in group 1 an air particle abrasion with 25 ?m aluminium trioxide (4 seconds at a pressure of 2.5 bars and subsequently a silane coupling agent (Espe Sil, 3M Unitek, Monrovia, USA was applicated on one side of each ceramic specimen (10 per group. In group 2 one side of each sample (20 per group was etched with 37.0 per cent orthophosphoric acid for two minutes and was followed by a silane application (Espe Sil, 3M Unitek, Monrovia, USA. After this procedure the self-ligating ceramic brackets Clarity SL (3M Unitek, Monrovia, USA brackets were bonded to the ceramic blocks and a thermocycling process started (5°C - 55°C, 6000 cycles. Then, shear bond strength and Adhesive Remnant Index (ARI were measured. To determine statistical differences Oneway-ANOVA and Tukey Post-hoc test were performed. Hydrofluoric acid seems not to be justifiable anymore for preparing the surface of dental ceramic restorations before bracket bonding. Sandblasting with 25 ?m aluminium trioxide and the use of orthophosphoric acid (37.0 per cent seem to prepare the surface of ceramic restoration sufficiently before ceramic bracket bonding. The found level of shear bond strength values seems to be sufficient for bonding ceramic brackets to ceramic restorations.

Andreas Faltermeier

2013-07-01

50

Are torque values of preadjusted brackets precise?  

OpenAIRE

OBJECTIVE: The aim of the present study was to verify the torque precision of metallic brackets with MBT prescription using the canine brackets as the representative sample of six commercial brands. MATERIAL AND METHODS: Twenty maxillary and 20 mandibular canine brackets of one of the following commercial brands were selected: 3M Unitek, Abzil, American Orthodontics, TP Orthodontics, Morelli and Ortho Organizers. The torque angle, established by reference points and lines, was measured by an ...

Alessandra Motta Streva; Flávio Augusto Cotrim-Ferreira; Daniela Gamba Garib; Paulo Eduardo Guedes Carvalho

2011-01-01

51

Effect of fluoride solutions on the shear bond strength of orthodontic brackets  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo deste estudo foi o de avaliar in vitro a resistência adesiva de bráquetes após o pré-tratamento do esmalte com diferentes soluções fluoretadas. Foram utilizados 48 incisivos bovinos hígidos recém-extraídos que foram aleatoriamente divididos em 4 grupos experimentais (n=12). CG (controle): [...] sem tratamento; FN: aplicação de flúor neutro por 4 min; FFA: aplicação de flúor fosfato acidulado (FFA) a 1,23% por 4 min; e VFS: aplicação de verniz de fluoreto de sódio a 5% por 6 h. Após o tratamento dos grupos, foi realizada a profilaxia do esmalte e os bráquetes foram fixados utilizando o compósito Transbond XT (3M), seguindo as especificações do fabricante. A resistência adesiva foi verificada através do teste de cisalhamento, realizado na Máquina de Ensaio Universal DL-2000 24 h após a fixação dos bráquetes. As superfícies dos dentes foram analisadas para verificação do índice de adesivo remanescente (IAR). Por meio dos testes estatísticos ANOVA e Tukey (?=5%), observou-se diferença estatisticamente significante entre os grupos estudados (p0,05). A análise dos escores do IAR revelou que grande parte das falhas ocorreram na interface esmalte-resina. Conclui-se que o tratamento do esmalte com FFA 1,23% e VFS a 5%, previamente à fixação de bráquetes ortodônticos, reduziu os valores de resistência adesiva ao cisalhamento Abstract in english The aim of this in vitro study was to evaluate the shear bond strength of brackets after pre-treatment with different fluoride solutions. This study used 48 freshly extracted sound bovine incisors that were randomly assigned to 4 experimental groups (n=12). CG: (control) without treatment; NF: 4 min [...] application of neutral fluoride; APF: application of 1.23% acidulated phosphate fluoride (APF) for 4 min; and SFV: application of 5% sodium fluoride varnish for 6 h. For each group, after surface treatment, prophylaxis of enamel and bracket bonding with Transbond XT composite resin (3M) were performed following the manufacturer's specifications. The shear bond strength was performed with a universal testing machine 24 h after fixing the brackets. The tooth surfaces were analyzed to verify the adhesive remnant index (ARI). Data were analyzed statistically by ANOVA and Tukey's test (?=0.05). There was statistically significant difference among the groups (p0.05). The analysis of ARI scores revealed that most failures occurred at the enamel-resin interface. It may be concluded that the pre-treatment of enamel with 1.23% APF and 5% SFV prior to fixing orthodontic brackets reduces shear bond strength values.

Gabriela da Rocha, Leódido; Hianna Oliveira, Fernandes; Mateus Rodrigues, Tonetto; Cristina Dupim, Presoto; Matheus Coêlho, Bandéca; Leily Macedo, Firoozmand.

52

An Investigation about the Influence of Bleaching on Shear Bond Strength of Orthodontic Brackets and on Enamel Colour  

OpenAIRE

The aim of the study was to investigate the effect of bleaching on the colouration of tooth enamel and shear bond strength of orthodontic ceramic brackets based upon current whitening practice. The bleaching and bonding techniques were performed on extracted bovine teeth for the investigation of their colorimetric spectrum and the adhesive bond strength on surface enamel. One group was designated as the control group with no pre-treatment. Another group was treated with a 45% hydrogen peroxid...

Isabell Immerz; Peter Proff; Piero Roemer; Claudia Reicheneder; Andreas Faltermeier

2012-01-01

53

Microhardness of Enamel Adjacent to Orthodontic Brackets After CO2 Laser Irradiation and Fluoride Application  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese Este estudo avaliou a eficácia do laser de CO2, associado ou não à aplicação de flúor na microdureza superficial do esmalte dentário adjacente a bráquetes ortodônticos. Foram selecionados 15 molares humanos, dos quais 30 fragmentos de esmalte com 4 mm2 foram obtidos. Os fragmentos foram incluídos em [...] tubos de PVC, contendo resina acrílica, preparados usando lixas d'água e discos de feltro e alumina. Bráquetes ortodônticos cortados ao meio foram colados no esmalte e 3 leituras de microdureza foram realizadas na superfície adjacente: inicial, após desafio cariogênico e final. Os espécimes foram divididos em 3 grupos (n=10): Grupo C - Controle, Grupo L - irradiado com laser de CO2 e Grupo FL - aplicação tópica de flúor e irradiação com laser de CO2. Após leitura inicial, os espécimes foram colocados em solução desmineralizadora por 32 h e a segunda leitura foi realizada para verificar se desmineralização foi uniforme em todos os grupos. Após os tratamentos, os espécimes foram submetidos a ciclagem DES-RE durante 8 dias seguida da leitura da microdureza superficial final. Os dados foram analisdos estatisticamente utilizando ANOVA e o teste de Duncan (?=0,05). Na mensuração final o grupo FL obteve maior valor de microdureza que os grupos C e L (p Abstract in english This study evaluated the effectiveness of carbon dioxide (CO2) laser combined or not with fluoride application on the surface microhardness of enamel adjacent to orthodontic brackets. Fifteen human molars were selected from which 30 enamel fragments measuring 4 mm2 were obtained. The fragments were [...] embedded in PCV tubes with acrylic resin and prepared using water abrasive paper, felt disks and alumina. Orthodontic brackets cut in half were bonded to enamel and 3 microhardness readings were performed on the adjacent surface, as follows: initial, after cariogenic challenge and final. The specimens were divided into the following 3 groups (n=10): Group C: control, Group L: irradiated with CO2 laser, and Group FL: topical fluoride application and CO2 laser irradiation. After initial reading, the specimens were placed in a demineralizing solution for 32 h and the second reading was to verify if demineralization was uniform in all groups. After the treatments, the specimens were submitted to DES-RE cycling for 8 days followed by final surface microhardness reading. The data were analyzed statistically using ANOVA and Duncan test (?=0.05). At the final measurement Group FL obtained higher microhardness value than Groups C and L (p

Leonardo Pucci, Stangler; Fabio Lourenco, Romano; Mariana Umekita, Shirozaki; Rodrigo, Galo; Alessandra Marques Correa, Afonso; Maria Cristina, Borsatto; Mirian Aiko Nakane, Matsumoto.

2013-09-01

54

Assessment of the dimensions and surface characteristics of orthodontic wires and bracket slots  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o objetivo desse estudo é avaliar as dimensões e as características superficiais de fios retangulares e slots de braquetes de diferentes marcas comerciais. MÉTODOS: trinta braquetes metálicos (0,022" x 0,028" e 0,022" x 0,030") foram divididos em três grupos: Grupo DYN/3M = Dyna-Lock, 3M/U [...] nitek, aço inoxidável (AI); Grupo STD/MO = Slim Morelli (AI); e Grupo NiFree/MO = Slim Morelli (Ni-Free). Já os fios retangulares (0,019" x 0,025"), de aço inoxidável, foram divididos em 2 grupos: Grupo MO = Morelli; Grupo 3M = 3M/Unitek. As mensurações dos slots dos braquetes e dos fios foram realizadas por dois métodos: (a) microscopia eletrônica de varredura (MEV), e (b) projeção de perfil. A análise da topografia superficial foi realizada qualitativamente, baseada em imagens microscópicas (MEV) e/ou por meio de um rugosímetro. Os resultados quantitativos foram submetidos à análise de variância (ANOVA) com o teste de Tukey (p Abstract in english OBJECTIVE: The purpose of this study was to evaluate the dimensions and surface characteristics of orthodontic wires and bracket slots of different commercial brands. METHODS: Thirty metallic brackets (0.022 x 0.028-in and 0.022 x 0.030-in) were divided in three groups: DYN/3M group = Dyna-Lock, 3M/ [...] Unitek (stainless steel, or SS); STD/MO group = Slim Morelli (SS); and Ni-Free/MO group = Slim Morelli (Ni-Free). The stainless steel wires (0.019 x 0.025in) were divided into two groups: MO group = Morelli; and 3M group = 3M/Unitek. The bracket and wire measurements were done by two methods: (a) Surface Electron Microscopy (SEM), and (b) Profile projection. The surface analysis was done qualitatively, based on SEM images and/or by a rugosimeter. The quantitative results were analyzed by ANOVA with Tukey's test (p

Gabriel Schmidt, Dolci; Ana Maria, Spohr; Eduardo Rigon, Zimmer; Ernani Menezes, Marchioro.

2013-04-01

55

Enamel Surface Roughness after Debonding of Orthodontic Brackets and Various Clean-Up Techniques  

OpenAIRE

Objective: This study aimed to evaluate enamel roughness after adhesive removal using different burs and an Er:YAG laser.Materials and Methods: The buccal surfaces of forty human premolars were sealed by two layers of nail varnish, except for a circular area of 3 mm in diameter on the middle third. The enamel surfaces were initially subjected to profilometry analysis and four parameters of surface irregularity (Ra, Rq, Rt and Rz) were recorded. Following bracket bonding and debonding, adhesiv...

Farzaneh Ahrari; Majid Akbari; Javad Akbari; Ghahraman Dabiri

2013-01-01

56

Shear bond strength of orthodontic brackets bonded using halogen light and light-emitting diode at different debond times  

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Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this in vitro study was to compare the photoactivation effects of QTH (Quartz-Tungsten-Halogen) and LED (Light-Emitting Diode) on the SBS (Shear Bond Strength) of orthodontic brackets at different debond times. Seventy-two bovine lower incisors were randomly divided into two groups accord [...] ing to the photoactivation system used (QTH or LED). The enamel surfaces were conditioned with Transbond self-etching primer, and APC (Adhesive Pre-Coated) brackets were used in all specimens. Group I was cured with QTH for 20 s and Group II with LED for 10 s. Both groups were subdivided according to the different experimental times after bonding (immediately, 24 h and 7 days). The specimens were tested for SBS and the enamel surfaces were analyzed according to the Adhesive Remnant Index (ARI). The statistical analysis included the Tukey's test to evaluate the main effects of photoactivation and debond time on SBS. The Chi-square test was used to compare the ARI values found for each group, and no statistically significant difference was observed. The debond time of 7 days for QTH photoactivation showed statistically greater values of SBS when compared to the immediate and 24 h periods. There was no statistically significant difference between the QTH and LED groups immediately and after the 24 h period. In conclusion, bonding orthodontic brackets with LED photoactivation for 10 s is suggested because it requires a reduced clinical chair time.

Rebeca, Di Nicoló; Maria Amelia Maximo de, Araujo; Levy Anderson César, Alves; Rodrigo Othavio de Assunção e, Souza; Daniel Maranha da, Rocha.

2010-03-01

57

Shear bond strength of orthodontic brackets bonded using halogen light and light-emitting diode at different debond times  

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Full Text Available The aim of this in vitro study was to compare the photoactivation effects of QTH (Quartz-Tungsten-Halogen and LED (Light-Emitting Diode on the SBS (Shear Bond Strength of orthodontic brackets at different debond times. Seventy-two bovine lower incisors were randomly divided into two groups according to the photoactivation system used (QTH or LED. The enamel surfaces were conditioned with Transbond self-etching primer, and APC (Adhesive Pre-Coated brackets were used in all specimens. Group I was cured with QTH for 20 s and Group II with LED for 10 s. Both groups were subdivided according to the different experimental times after bonding (immediately, 24 h and 7 days. The specimens were tested for SBS and the enamel surfaces were analyzed according to the Adhesive Remnant Index (ARI. The statistical analysis included the Tukey's test to evaluate the main effects of photoactivation and debond time on SBS. The Chi-square test was used to compare the ARI values found for each group, and no statistically significant difference was observed. The debond time of 7 days for QTH photoactivation showed statistically greater values of SBS when compared to the immediate and 24 h periods. There was no statistically significant difference between the QTH and LED groups immediately and after the 24 h period. In conclusion, bonding orthodontic brackets with LED photoactivation for 10 s is suggested because it requires a reduced clinical chair time.

Rebeca Di Nicoló

2010-03-01

58

Evaluation of different LED light-curing devices for bonding metallic orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo deste estudo foi avaliar a influência de diferentes aparelhos de luz tipo LED na colagem de bráquetes ortodônticos, através do teste de resistência ao cisalhamento e do Índice de Remanescente do Adesivo (IRA). Coroas de 60 incisivos bovinos receberam a colagem de bráquetes com compósito T [...] ransbond XT. A amostra foi dividida em 4 grupos (n=15) de acordo com os seguintes tipos de fotoativação: HL: controle, luz halógena; OR= Ortholux LED; UL= Ultraled XP e RD= Radii LED. Todas as fotoativações foram realizadas por 40 s. O teste de resistência ao cisalhamento foi realizado em máquina universal de ensaios mecânicos à velocidade de 0,5 mm/min. Os dados foram analisados estatisticamente pelo ANOVA e teste de Tukey. Os escores do IRA foram avaliados em lupa estereoscópica e analisados estatisticamente pelo teste de Kruskal-Wallis. O nível de significância de 5% foi adotado para todas as análises. Os valores médios (MPa) e o desvio-padrão do teste de resistência ao cisalhamento foram 9,82 (3,28), 12,70 (3,35), 9,04 (2,80) e 11,22 (2,36) para o grupo HL, OR, UL e RD, respectivamente. O grupo OR apresentou os maiores valores médios de resistência ao cisalhamento. O grupo HL diferiu significativamente (p0,05). Quanto ao escores do IRA, nenhuma diferença estatística significante foi observada (p>0,05) entre os grupos. Concluiu-se que as unidades de luz Ortholux LED e Radii LED proporcionaram maiores valores de resistência adesiva aos bráquetes. Abstract in english The aim of this study was to assess the influence of different light-emitting diodes (LED) light-curing devices for bonding orthodontic brackets, using the shear bond strength and analysis of adhesive remnant index (ARI). Crowns from 60 bovine incisors received brackets bonded with Transbond XT. Spe [...] cimens were divided into 4 groups (n=15) according to the light-curing procedures: HL = control, halogen light; OR = Ortholux LED; UL = Ultraled XP, and RD = Radii LED. All light-curing procedures were performed for 40 s. Shear bond strength test was evaluated using an universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test. The ARI scores were evaluated with a stereoscopic magnifying glass and analyzed statistically by Kruskal-Wallis test. A significance level of 5% was set for all analyses. Shear bond strength means in MPa and standard deviations were 9.82 (3.28), 12.70 (3.35), 9.04 (2.80) and 11.22 (2.36) for HL, OR, UL and RD, respectively. OR presented the highest shear bond strength mean value. HL differed significantly (p0.05). Regarding the ARI scores, no statistically significant difference was observed (p>0.05) among the groups. In conclusion, Ortholux LED and Radii LED units provided the highest values of bracket adhesive strength.

Corina Maia de Souza, Pinto; José Tarcísio Lima, Ferreira; Mírian Aiko Nakane, Matsumoto; Maria Cristina, Borsatto; Raquel Assed Bezerra da, Silva; Fábio Lourenço, Romano.

59

The effect of tooth bleaching on the shear bond strength of orthodontic brackets using self-etching primer systems  

Science.gov (United States)

Objective: The purpose of this study was to determine the effect of 10% carbamide peroxide and 38% hydrogen peroxide bleaching agents on the shear bond strength of orthodontic brackets using self-etching primer systems. Methods: Forty five freshly extracted human premolar teeth were randomly divided into 3 groups of 15 teeth each: control (group 1), 10% carbamide peroxide at-home bleached (group 2), and 38% hydrogen peroxide in-office bleached (group 3). Three weeks later, all brackets were bonded using a self-etching primer system. The shear bond strength of these brackets was measured and recorded in MPa. Adhesive remnant index (ARI) scores were determined after the brackets failed. Data were analyzed using Kruskal- Wallis test, pairwise comparisons were made using the Mann-Whitney U test and ARI scores were analyzed using a chi-square test at a significance level of P.05). ARI scores did not differ significantly among the 3 groups. Conclusions: The use of 10% carbamide peroxide bleaching does not significantly reduce shear bond strength values. In contrast, use of 38% hydrogen peroxide bleaching significantly reduces these values. PMID:23408777

Akin, Mehmet; Aksakalli, Sertac; Basciftci, Faruk Ayhan; Demir, Abdullah

2013-01-01

60

A comparative study on time efficiency management of self ligating brackets with conventional ligating brackets on orthodontic subjects in North Karnataka  

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Full Text Available Background: Self-Ligating brackets were originally designed with the intention to reduce the time needed to change wires compared with the use of wire ligatures. However, the advent of elastomeric ligatures meant that this perceived advantage was diminished. Objective: To compare aligning efficiency, rate of retraction and torque expression of Self Ligating bracket (SLB system with Conventional Pre adjusted Edgewise bracket (CLB system. Materials and Methods: Twelve patients were selected and divided into two groups treated with self ligating brackets (SLB, n=6 and conventional ligating brackets (CLB, n=6. The brackets used were 0.22 slot McLaughlin Bennet Trevesi (MBT prescription. Aligning was evaluated with 0.14 Niti followed by 19X25 Heat Activated Ni Ti and then 19X25 stainless steel wires for retraction within 4 months. The rate of retraction was evaluated per month and torque loss after space closure was also estimated. Results: Alignment Efficiency shows significant changes with SLB compared to CLB and also save more than 30% of chair side time during wire adjustments while rate of en masse retraction in SLB shows statistically non significance as compared to CLB system. In case of upper incisor changes when compared between two groups showed less torque loss in SLB than CLB although which was statistically no significant but % difference show SLB have better improvement result than CLB.

Smita B. Patil

2014-01-01

61

Streptococcus mutans counts in plaque adjacent to orthodontic brackets bonded with resin-modified glass ionomer cement or resin-based composite  

OpenAIRE

This study investigated the number of Streptococcus mutans CFU (colony forming units) in the saliva and plaque adjacent to orthodontic brackets bonded with a glass ionomer cement - GIC (Fuji Ortho) or a resin-based composite - RC (Concise). Twenty male and female patients, aged 12 to 20 years, participated in the study. Saliva was collected before and after placement of appliances. Plaque was collected from areas adjacent to brackets and saliva was again collected on the 15th, 30th, and 45th ...

Solange Machado Mota; Carla Enoki; Izabel Yoko Ito; Ana Maria Elias; Mírian Aiko Nakane Matsumoto

2008-01-01

62

Influence of surface treatment on shear bond strength of orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese INTRODUÇÃO: foram avaliadas as forças de cisalhamento após colagem de braquetes ortodônticos em superfícies resinosas microparticuladas ou micro-híbridas, após diferentes tratamentos de superfície. MÉTODOS: foram utilizados 280 corpos de prova, divididos em grupos de 10 elementos cada, sendo 140 pre [...] enchidos com resina microparticulada Durafill e 140 com resina micro-híbrida Charisma. Os tratamentos de superfície envolveram: ácido fosfórico, ácido fluorídrico, jato de bicarbonato de sódio, jato de óxido de alumínio, pedra e broca. A silanagem foi utilizada em metade dos grupos. O cisalhamento foi realizado com a máquina universal de testes EMIC DL 10000 MF, com célula de 10kg e velocidade de 0,5mm/min. As comparações entre as forças de cisalhamento foram obtidas por meio da análise de variância, e o grau de interação entre os tipos de compósito e o preparo de superfície foram obtidos por meio de uma regressão multivariada. RESULTADOS: as médias e desvios-padrão foram: jato de bicarbonato = 11,27 ± 2,78; broca = 9,26 ± 3,01; pedra = 7,95 ± 3,67; jato de óxido de alumínio = 7,04 ± 3,21; ácido fosfórico = 5,82 ± 1,90; ácido fluorídrico = 4,54 ± 2,87; e sem preparo = 2,75 ± 1,49. Um acréscimo de 1,94MPa foi obtido com o uso do compósito Charisma. A silanagem reduziu em 0,68MPa as médias do compósito Charisma, e aumentou o Durafill com uso do jato de bicarbonato (0,83), broca (0,98) e pedra (0,46). CONCLUSÃO: os preparos com jato de bicarbonato, broca e pedra obtiveram médias de forças apropriadas para colagem. O compósito Charisma apresentou forças de maior intensidade que as da resina Durafill. Abstract in english INTRODUCTION: The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed. METHODS: Two hundred and eighty test samples were divided into 28 groups (n = 10), where 140 specimens were filled with Durafill m [...] icro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane) was applied. The surface treatment methods were: Phosphoric and hydrofluoric acid etching, sodium bicarbonate and aluminum oxide blasting, stone and burs. A Universal Instron Machine was used to apply an occlusal shear force directly to the resin composite bracket surface at a speed of 0.5 mm/min. The means were compared using analysis of variance and multivariate regression to assess the interaction between composites and surface treatment methods. RESULTS: Means and standard deviations for the groups were: Sodium bicarbonate jet 11.27±2.78; burs 9.26±3.01; stone 7.95±3.67; aluminum oxide blasting 7.04±3.21; phosphoric acid 5.82±1.90; hydrofluoric acid 4.54±2.87, and without treatment 2.75±1.49. An increase of 1.94 MPa in shear bond strength was seen in Charisma groups. Silane agent application reduced the Charisma shear bond strength by 0.68 Mpa, but increased Durafill means for bicarbonate blasting (0.83), burs (0.98) and stone drilling (0.46). CONCLUSION: The sodium bicarbonate blasting, burs and stone drilling methods produced adequate shear bond strength and may be suitable for clinical use. The Charisma micro hybrid resin composite showed higher shear bond means than Durafill micro particle composite.

Ione Helena Vieira Portella, Brunharo; Daniel Jogaib, Fernandes; Mauro Sayão de, Miranda; Flavia, Artese.

2013-06-01

63

Orthodontic materials research and applications: part 2. Current status and projected future developments in materials and biocompatibility.  

Science.gov (United States)

The purpose of this 2-part opinion article was to project the developments expected to occur in the next few years in orthodontic materials research and applications. Part 1 reviewed developments in bonding to enamel. Part 2 looks at other orthodontic materials applications and explores emerging research strategies for probing the biological properties of materials. In the field of metallic brackets, expansion of the use of titanium alloys with improved hardness and nickel-free steels with better corrosion resistance and increased hardness is expected. Manufacturing techniques might be modified to include laser-welding methods and metal injection molding. Esthetic bracket research will involve the synthesis of high-crystallinity biomedical polymers with increased hardness and stiffness, decreased water sorption, and improved resistance to degradation. New plastic brackets might incorportate ceramic wings. Fiber-reinforced composite archwires, currently experimental, could soon be commercially available, and long-term applications of shape-memory plastics might become viable. Advancements in elastomeric materials will result in polymers with reduced relaxation, broader use of fluoride-releasing elastomers with decreased relaxation, and large-scale film coating of elastomers to decrease reactivity, water sorption, and degradation. Finally, biocompatibility assessments will incorporate testing of potential endocrinological action. New polymer formulations might be tested in adhesive and plastic bracket manufacturing, based on benzoic ring-free monomers to avoid the adverse effects of the estrogenic molecule bisphenol-A. PMID:17276868

Eliades, Theodore

2007-02-01

64

Orthodontics  

OpenAIRE

The authors of this article offer an introduction to the field of orthodontics. They present the latest advances in orthodontic appliances and some of the possible consequences of orthodontic treatment. They discuss a number of cases and offer examples of some of the more common problems that the orthodontist is asked to treat. Such cases include severe Class II, division 1 malocclusion, surgical orthodontics, “long-face” syndrome, adult orthodontics-TMJ-periodontics, late adult growth, a...

Hemrend, Bernard; Altuna, Gurkan; Tompson, Bryan

1989-01-01

65

Comparison of Shear Bond Strength of Orthodontic Brackets Bonded to Enamel Prepared By Er:YAG Laser and Conven-tional Acid-Etching  

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Full Text Available Introduction: The purpose of this study was to compare shear bond strength (SBS of orthodontic brackets bonded to enamel prepared by Er:YAG laser with two different powers and conventional acid-etching.Materials and Methods: Forty-five human premolars extracted for orthodontic purposes were randomly assigned to three groups based on conditioning method: Group 1- conventional etching with 37% phosphoric acid; Group 2- irradiation with Er:YAG laser at 1 W; and Group 3- irradiation with Er:YAG laser at 1.5 W. Metal brackets were bonded on prepared enamel using a light-cured composite. All groups were subjected to thermocycling process. Then, the specimens mounted in auto-cure acryle and shear bond strength were measured using a universal testing machine with a crosshead speed of 0.5 mm per second. After debonding, the amount of resin remaining on the teeth was determined using the adhesive remnant index (ARI scored 1 to 5. One-way analysis of variance was used to compare shear bond strengths and the Kruskal-Wallis test was performed to evaluate differences in the ARI for different etching types.Results: The mean and standard deviation of conventional acid-etch group, 1W laser group and 1.5W laser group was 3.82 ± 1.16, 6.97 ± 3.64 and 6.93 ± 4.87, respectively.Conclusion: The mean SBS obtained with an Er:YAG laser operated at 1W or 1.5W is approximately similar to that of conventional etching. However, the high variability of values in bond strength of irradiated enamel should be considered to find the appropriate parameters for applying Er:YAG laser as a favorable alternative for surface conditioning.

M.H. Hosseini

2012-01-01

66

[Hardened anodized aluminum as a replacement material for bracket manufacture].  

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Attention has been repeatedly drawn to the problem of corrosion and the risk of allergic reaction to nickel resulting from the use of stainless steel brackets. In the search for a suitable alternative, manufacturers have turned to thin coating technology using hardened anodized aluminium. Applying resistance to corrosion and abrasion as the criteria to be met, they have selected aluminium alloy type 6082 as the material of choice. Purpose of this study is to examine the physical suitability of this material. Using the above noted alloy, 60 prototype brackets were made with a hardened anodized surface. They were then subjected to the following 3 stress tests: first an abrasion test using a tooth polishing machine, second, a deformation test using a device designed to simulate torque movement, and, third, a corrosion test. The effects on the brackets resulting from the three types of stress were evaluated by light microscopy. A quantitative analysis of the corrosion test was performed by ICP spectrometry. The control group consisted of conventional stainless steel brackets. The light microscopic analysis revealed no evidence of surface damage or signs of deformation in the prototype brackets. The steel brackets, on the other hand, showed clear signs of wear and corrosion. The quantitative analysis of the corrosion solution revealed metallic ion wear of 1.75 ng x mm-2 x h-1 for the prototypes subjected to abrasion. The steel brackets showed at a factor of around 104.6 metallic ion wear of 183 ng x mm-2 x h-1. In addition to this, no Ni ions were found in the corrosion solution of the prototype brackets.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7851828

Fischer-Brandies, H; Bönhoff, M

1994-12-01

67

Notching of orthodontic bonding resin to facilitate ceramic bracket debond--an ex vivo investigation.  

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This ex vivo study assessed the potential of introducing a notch in the bond layer, as a means of facilitating the removal of ceramic brackets. Sixty extracted premolar teeth were divided into three groups of 20 teeth and bonded with Intrigue brackets using Concise chemically-cured adhesive. The bonding technique was modified with groups 1 and 2 by introducing a notch in the bond layer. Group 1 was notched from the gingival aspect, group 2 from the occlusal, and group 3 served as a control. The brackets were removed by applying a shear load from the gingival aspect using an Instron universal testing machine. The mean force to debond was calculated for each group. The results showed that introducing a notch significantly reduced the mean and maximal debond forces. This was confirmed with Weibull analysis with the notched specimens having a higher probability of failure at any force. In addition, ceramic bracket fracture was eliminated. Notching the bonding resin may be helpful in facilitating the removal of ceramic brackets. PMID:9884780

Larmour, C J; McCabe, J F; Gordon, P H

1998-11-01

68

Avaliação in vitro da liberação de níquel por braquetes metálicos In vitro nickel release from metallic orthodontic brackets  

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Full Text Available O aço inoxidável austenítico é utilizado para confecção de dispositivos ortodônticos e contém cerca de 8-10% de níquel em sua composição, metal este responsável por reações alérgicas de hipersensibilidade. Acredita-se que a liberação de níquel dos dispositivos metálicos pode provocar dermatites de contato em pacientes suscetíveis. Este estudo laboratorial avaliou a influência de três variáveis na liberação de níquel: 1 o tipo de liga do braquete; 2 o tipo de solução de imersão e 3 o esforço mecânico nas canaletas dos braquetes de aço inoxidável austenítico. Foram avaliados seis grupos experimentais e dois grupos controles. As amostras foram imersas em tubos de ensaio contendo saliva artificial ou solução salina, sendo mantidas sob agitação e temperatura constante (37ºC. A quantidade de níquel presente nas soluções foi avaliada com espectrofotômetro de absorção atômica (Varian - Spectra A55 em dois momentos: após uma semana e após duas semanas. Os resultados revelaram que os braquetes de aço inoxidável com baixo teor de níquel apresentaram menor liberação deste elemento. Foi possível constatar que o tipo de solução alterou o padrão de liberação de níquel pelos dispositivos avaliados. O esforço mecânico aplicado sobre os braquetes de aço inoxidável austenítico não alterou a quantidade de níquel liberada.Austenitic stainless steel is frequently used to fabricate orthodontic appliances, which contains 8-10% of nickel. Such metal is responsible for hypersensitivity allergic reactions. Thus, nickel release of orthodontic appliances may be responsible for contact dermatitis in sensitive patients. This study assessed the influence of three variables in nickel release of metal brackets: 1 type of metal alloy; 2 type of solution used for immersion; and 3 mechanical stress. Six experimental and two control groups were assessed. The specimens were immersed in saline solution or artificial saliva, maintained in constant agitation in controlled temperature environment (37ºC. Nickel present in solutions was measured with atomic spectroscopy (Varian-Spectra A55 in two moments: after one and after two weeks. The results showed that brackets made of low nickel contend alloy released less nickel than standard ones. It was possible to notice that the type of solution alters the pattern of nickel release. Mechanical stress applied in the slots of standard brackets did not influence nickel release.

Marina Lara Sória

2005-06-01

69

Avaliação in vitro da liberação de níquel por braquetes metálicos / In vitro nickel release from metallic orthodontic brackets  

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Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O aço inoxidável austenítico é utilizado para confecção de dispositivos ortodônticos e contém cerca de 8-10% de níquel em sua composição, metal este responsável por reações alérgicas de hipersensibilidade. Acredita-se que a liberação de níquel dos dispositivos metálicos pode provocar dermatites de c [...] ontato em pacientes suscetíveis. Este estudo laboratorial avaliou a influência de três variáveis na liberação de níquel: 1) o tipo de liga do braquete; 2) o tipo de solução de imersão e 3) o esforço mecânico nas canaletas dos braquetes de aço inoxidável austenítico. Foram avaliados seis grupos experimentais e dois grupos controles. As amostras foram imersas em tubos de ensaio contendo saliva artificial ou solução salina, sendo mantidas sob agitação e temperatura constante (37ºC). A quantidade de níquel presente nas soluções foi avaliada com espectrofotômetro de absorção atômica (Varian - Spectra A55) em dois momentos: após uma semana e após duas semanas. Os resultados revelaram que os braquetes de aço inoxidável com baixo teor de níquel apresentaram menor liberação deste elemento. Foi possível constatar que o tipo de solução alterou o padrão de liberação de níquel pelos dispositivos avaliados. O esforço mecânico aplicado sobre os braquetes de aço inoxidável austenítico não alterou a quantidade de níquel liberada. Abstract in english Austenitic stainless steel is frequently used to fabricate orthodontic appliances, which contains 8-10% of nickel. Such metal is responsible for hypersensitivity allergic reactions. Thus, nickel release of orthodontic appliances may be responsible for contact dermatitis in sensitive patients. This s [...] tudy assessed the influence of three variables in nickel release of metal brackets: 1) type of metal alloy; 2) type of solution used for immersion; and 3) mechanical stress. Six experimental and two control groups were assessed. The specimens were immersed in saline solution or artificial saliva, maintained in constant agitation in controlled temperature environment (37ºC). Nickel present in solutions was measured with atomic spectroscopy (Varian-Spectra A55) in two moments: after one and after two weeks. The results showed that brackets made of low nickel contend alloy released less nickel than standard ones. It was possible to notice that the type of solution alters the pattern of nickel release. Mechanical stress applied in the slots of standard brackets did not influence nickel release.

Marina Lara, Sória; Luciane, Menezes; Berenice, Dedavid; Marçal, Pires; Susana, Rizzatto; Luiz Cesar da, Costa Filho.

2005-06-01

70

Influência da secção transversa de fios ortodônticos na fricção superficial de braquetes autoligados / Influence of the cross-section of orthodontic wires on the surface friction of self-ligating brackets  

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Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: o objetivo do presente trabalho foi determinar a força de atrito estático entre braquetes de aço inoxidável autoligados com sistema de fechamento resiliente e fios ortodônticos redondos e retangulares do mesmo material. MÉTODOS: empregaram-se 30 braquetes referentes aos caninos superiores [...] divididos em 6 grupos formados por braquetes autoligados Smartclip, In-Ovation R e convencionais Gemini amarrados com ligaduras elásticas. A hipótese testada neste trabalho foi quanto à possibilidade dos braquetes autoligados ativos serem suscetíveis à elevação da força de atrito com o aumento e alteração da secção transversal dos fios ortodônticos. Os ensaios foram realizados com tração de 30s em fios de aço inoxidável 0,020" e 0,019"X0,025" na máquina de ensaios Emic DL 10000, com uma célula de carga de 20 newtons. Cada conjunto braquete/fio foi responsável pela geração de quatro corpos de prova, totalizando 120 leituras. As comparações entre as médias foram realizadas através da Análise de Variância (one way ANOVA) com correções pelo coeficiente de Bonferroni. RESULTADOS E CONCLUSÃO: os braquetes autoligados apresentaram maior força de atrito do que os braquetes convencionais amarrados com ligaduras elásticas. O grupo Smartclip foi o mais efetivo no controle do atrito (p Abstract in english OBJECTIVES: The purpose of this study was to assess the surface friction produced by self-ligating stainless steel brackets equipped with a resilient closure system and compare the friction generated during traction of round and rectangular orthodontic wires made from the same material. METHODS: Thi [...] rty maxillary canine brackets were divided into six groups comprising SmartClip and In-Ovation R self-ligating brackets, and conventional Gemini brackets tied with elastomeric ligatures. This investigation tested the hypothesis that self-ligating brackets are susceptible to increases in friction that are commensurate with increases and changes in the cross-section of orthodontic wires. Traction was performed with the aid of thirty segments of 0.020" and 0.019" x 0.025" stainless steel wires in an EMIC DL 10000 testing machine with a 2N load cell. Each set of bracket/wire generated four samples, totaling 120 readings. Comparisons between means were performed using analysis of variance (one way ANOVA) corrected with the Bonferroni coefficient. RESULTS AND CONCLUSION: The self-ligating brackets exhibited lower friction than conventional brackets tied with elastomeric ligatures. The SmartClip group was the most effective in controlling friction (p

Roberta, Buzzoni; Carlos N., Elias; Daniel J., Fernandes; José Augusto M., Miguel.

2011-08-01

71

Corrosion Inhibitory Ability of Ocimum Sanctum Linn (Tulsi Rinse on Ion Release from Orthodontic Brack-ets in Some Mouthwashes: An Invitro Study  

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Full Text Available Introduction: In the oral environment, orthodontic appliances are exposed to potentially damaging physical and chemical agents which may cause metallic corrosion. Corrosion will occur continuously in mouth, due to release of irons with abrasion by food, liquids etc. The purpose of this study was to measure the amount of metal ion release from orthodontic brackets when kept in different mouthwashes and effect of tulsi rinse on ion release when combined with different mouthwashes. Methods: Three hundred and twenty stainless steel brackets (0.022” were divided randomly into 8 equal groups and immersed in Mouthwash-A and, Mouthwash-B and mouthwash-C and distilled deionized water. These mouthwashes and distilled deionized water were all sepa-rately mixed with tulsi rinse and incubated at 37°C for 45 days. Nickel, Chromium, iron, copper and manganese released from the orthodontic brackets were measured with an inductively coupled plasma spectrometer. Results: Ion release in deionized water was higher (p<0.05 than in the 3 mouthwashes. Higher ion release was also found with Mouthwash-B compared with other 2 mouthwashes. There is no difference (p>0.05 in nickel, chromium, iron and copper ion release in the Mouthwash-A and Mouthwash-C. Tulsi rinse showed significant reduction (p<0.05 in all ion release in 3 mouthwashes used along with distilled deionzed water group. Conclusion: If ion release is concerned, Mouthwash-C mixed with tulsi rinse might be better option than Mouthwash-A as well as Mouthwash-B for orthodontic patients with stainless steel brackets.

Roopal Patel, Sheron Bhanat, Dolly Patel, Bhadra Shah

2014-01-01

72

Comparison of frictional forces between aesthetic orthodontic coated wires and self-ligation brackets  

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Objective The purpose of this study was to evaluate the clinical efficacy of polymer- and rhodium-coated wires compared to uncoated wires by measuring the frictional forces using self-ligation brackets. Methods 0.016-inch nickel titanium (NiTi) wires and 0.017 × 0.025-inch stainless steel (SS) wires were used, and the angulations between the brackets and wires were set to 0°, 5°, and 10°. Upper maxillary premolar brackets (Clippy-C®) with a 0.022-inch slot were selected for the study and a tensile test was performed with a crosshead speed of 5 mm/min. The maximum static frictional forces and kinetic frictional forces were recorded and compared. Results The maximum static frictional forces and the kinetic frictional forces of coated wires were equal to or higher than those of the uncoated wires (p < 0.05). The maximum static frictional forces of rhodium-coated wires were significantly higher than those of polymer-coated wires when the angulations between the brackets and wires were set to (i) 5° in the 0.016-inch NiTi wires and (ii) all angulations in the 0.017 × 0.025-inch SS wires (p < 0.05). The kinetic frictional forces of rhodium-coated wires were higher than those of polymer-coated wires, except when the angulations were set to 0° in the 0.016-inch NiTi wires (p < 0.05). Conclusions Although the frictional forces of the coated wires with regards to aesthetics were equal to or greater than those of the uncoated wires, a study under similar conditions regarding the oral cavity is needed in order to establish the clinical implications. PMID:25133130

Kim, Yunmi; Cha, Jung-Yul; Hwang, Chung-Ju; Tahk, Seon Gun

2014-01-01

73

Does the time interval after bleaching influence the adhesion of orthodontic brackets?  

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Objective To test the null hypothesis that no difference exists between the effects of at-home bleaching and in-office bleaching on shear bond strength (SBS) with bracket bonding at 4 different time intervals after dental bleaching. Methods Ninety extracted human premolars were randomly divided into 9 groups (n = 10) according to the bleaching methods used (at-home bleaching and in-office bleaching) and the storage time in artificial saliva (30 min, 1 day, 2 weeks, and 3 weeks before bonding). The control group was stored in artificial saliva for 7 days. Brackets were bonded with the Transbond XT adhesive system, and SBS testing was performed. The adhesive remnant index (ARI) was used to assess the amount of resin remaining on the enamel surfaces after debonding. The SBS data were analyzed by analysis of variance (ANOVA) and the Tukey test. For the ARI, the Kruskal-Wallis test was performed. Significance for all statistical tests was predetermined to be p < 0.05. Results The SBS of the unbleached group was significantly higher (p < 0.05) than that of the bleached groups (except for the group bonded 30 min after at-home bleaching). Conclusions The null hypothesis was not totally rejected. All bleaching groups tested had decreased SBS of the brackets to the enamel, except for the group bonded 30 min after at-home bleaching. The SBS returned to values close to those of the unbleached enamel within 3 weeks following bleaching. PMID:24228239

Nascimento, Glaucia Cristina Rodrigues; de Miranda, Cyndi Albuquerque; Machado, Sissy Maria Mendes; Brandão, Gustavo Antonio Martins; de Almeida, Haroldo Amorim

2013-01-01

74

Are torque values of preadjusted brackets precise?  

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Full Text Available OBJECTIVE: The aim of the present study was to verify the torque precision of metallic brackets with MBT prescription using the canine brackets as the representative sample of six commercial brands. MATERIAL AND METHODS: Twenty maxillary and 20 mandibular canine brackets of one of the following commercial brands were selected: 3M Unitek, Abzil, American Orthodontics, TP Orthodontics, Morelli and Ortho Organizers. The torque angle, established by reference points and lines, was measured by an operator using an optical microscope coupled to a computer. The values were compared to those established by the MBT prescription. RESULTS: The results showed that for the maxillary canine brackets, only the Morelli torque (-3.33º presented statistically significant difference from the proposed values (-7º. For the mandibular canines, American Orthodontics (-6.34º and Ortho Organizers (-6.25º presented statistically significant differences from the standards (-6º. Comparing the brands, Morelli presented statistically significant differences in comparison with all the other brands for maxillary canine brackets. For the mandibular canine brackets, there was no statistically significant difference between the brands. CONCLUSIONS: There are significant variations in torque values of some of the brackets assessed, which would clinically compromise the buccolingual positioning of the tooth at the end of orthodontic treatment.

Alessandra Motta Streva

2011-08-01

75

Streptococcus mutans counts in plaque adjacent to orthodontic brackets bonded with resin-modified glass ionomer cement or resin-based composite  

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Full Text Available This study investigated the number of Streptococcus mutans CFU (colony forming units in the saliva and plaque adjacent to orthodontic brackets bonded with a glass ionomer cement - GIC (Fuji Ortho or a resin-based composite - RC (Concise. Twenty male and female patients, aged 12 to 20 years, participated in the study. Saliva was collected before and after placement of appliances. Plaque was collected from areas adjacent to brackets and saliva was again collected on the 15th, 30th, and 45th day after placement. On the 30th day, 0.4% stannous fluoride gel was applied for 4 minutes. No significant modification in the number of Streptococcus mutans CFU in saliva was observed after placement of the fixed orthodontic appliances. On the 15th day, the percentage of Streptococcus mutans CFU in plaque was statistically lower in sites adjacent to GIC-bonded brackets (mean = 0.365 than in those adjacent to RC-bonded brackets (mean = 0.935. No evidence was found of a contribution of GIC to the reduction of CFU in plaque after the 15th day. Topical application of stannous fluoride gel on the 30th day reduced the number of CFU in saliva, but not in plaque. This study suggests that the antimicrobial activity of GIC occurs only in the initial phase and is not responsible for a long-term anticariogenic property.

Solange Machado Mota

2008-03-01

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Streptococcus mutans counts in plaque adjacent to orthodontic brackets bonded with resin-modified glass ionomer cement or resin-based composite  

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Full Text Available SciELO Brazil | Language: English Abstract in english This study investigated the number of Streptococcus mutans CFU (colony forming units) in the saliva and plaque adjacent to orthodontic brackets bonded with a glass ionomer cement - GIC (Fuji Ortho) or a resin-based composite - RC (Concise). Twenty male and female patients, aged 12 to 20 years, parti [...] cipated in the study. Saliva was collected before and after placement of appliances. Plaque was collected from areas adjacent to brackets and saliva was again collected on the 15th, 30th, and 45th day after placement. On the 30th day, 0.4% stannous fluoride gel was applied for 4 minutes. No significant modification in the number of Streptococcus mutans CFU in saliva was observed after placement of the fixed orthodontic appliances. On the 15th day, the percentage of Streptococcus mutans CFU in plaque was statistically lower in sites adjacent to GIC-bonded brackets (mean = 0.365) than in those adjacent to RC-bonded brackets (mean = 0.935). No evidence was found of a contribution of GIC to the reduction of CFU in plaque after the 15th day. Topical application of stannous fluoride gel on the 30th day reduced the number of CFU in saliva, but not in plaque. This study suggests that the antimicrobial activity of GIC occurs only in the initial phase and is not responsible for a long-term anticariogenic property.

Solange Machado, Mota; Carla, Enoki; Izabel Yoko, Ito; Ana Maria, Elias; Mírian Aiko Nakane, Matsumoto.

2008-03-01

77

Properties of Composite Materials Used for Bracket Bonding  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo desse estudo foi avaliar a resistência ao cisalhamento no esmalte, resistência flexural, módulo flexural, tensão de contração de polimerização de duas resinas flow e uma resina ortodôntica. Os bráquetes ortodônticos foram colados em 45 pré-molares humanos e divididos: Transbond XT, Filtek [...] Z-350 flow, Opallis flow e testado para resistência ao cisalhamento (n=15). Para a resistência e módulo flexural espécimes foram confeccionados e testados sob flexão. Para o teste de tensão de contração de polimerização, espécimes cilíndricos foram confeccionados e monitorados com um extensômetro (Instron). Os dados foram submetidos aos testes ANOVA a um critério e Tukey (?=0,05) para contraste de média. (n=15). A resistência de união das resinas flow foram significantemente menos que o da resina ortodôntica (p>0,05). A resistência flexural não demonstrou diferença significante entre os grupos testados (p>0,05). O módulo flexural da resina ortodôntica foi significantemente maior que o grupo das resinas flow (p Abstract in english 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 X [...] T, 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 (?=0.05). The shear bond strength values were significantly lower (p0.05) while the flexural modulus was significantly higher (p

Ana Caroline Silva, Gama; Andre Guaraci de Vito, Moraes; Lilyan Cardoso, Yamasaki; Alessandro Dourado, Loguercio; Ceci Nunes, Carvalho; Jose, Bauer.

2013-06-01

78

In vitro corrosion of metallic orthodontic brackets: influence of artificial saliva with and without fluorides  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: este estudo in vitro verificou a resistência à corrosão de braquetes metálicos, avaliando-se os aspectos superficiais em microscopia eletrônica de varredura (MEV) e os componentes residuais formados. MÉTODOS: a amostra consistiu de 17 conjuntos de braquetes de quatro diferentes ligas metál [...] icas: titânio, cobalto-cromo, aço inoxidável com baixa concentração de níquel e com cobertura de nitreto de titânio (TiN). Doze conjuntos foram submetidos à corrosão por imersão em 50ml de saliva artificial (pH 6,5) e 4 em saliva (pH 6,5) contendo flúor (2g/l), todos sob temperatura de 37ºC, e analisados após 7, 9 e 11 semanas. Uma montagem foi mantida como controle. As análises consistiram na avaliação qualitativa da corrosão por meio das imagens obtidas no MEV, na avaliação semiquantitativa da composição química dos resíduos superficiais por meio de MEV-EDS e da quantidade de íons liberados nas salivas na avaliação da espectrofotometria de absorção atômica. RESULTADOS: os resultados demonstraram que os braquetes com liga de titânio puro e os de aço com baixa concentração de níquel foram superiores em relação à resistência à corrosão. A liga de cobalto-cromo foi a que apresentou maior corrosão. Na presença do flúor, observaram-se maiores alterações em todas as ligas, com destaque para as de aço cobertos com TiN e as de cobalto-cromo. CONCLUSÃO: apesar de se observar a corrosão no MEV, a espectrofotometria mostrou baixo desprendimento de íons nas salivas artificiais, porém a presença do flúor interferiu negativamente na resistência à corrosão. Abstract in english OBJECTIVE: This in vitro study verified the resistance to corrosion of metallic brackets, evaluating the superficial aspects in scanning electron microscopy (SEM) and the residual components. METHODS: The sample consisted of 17 sets of brackets of four different metallic alloys: Titanium, Cobalt-Chr [...] omium, Stainless steel with low nickel concentration and with titanium nitride coating (NiTi). Twelve sets were submitted to corrosion by immersion in 50 ml of artificial saliva (pH 6.5) and four in saliva (pH 6.5) containing fluoride (2 g/l), all at a temperature of 37 ºC and analyzed after 7, 9 and 11 weeks. One was kept as control set. The analysis consisted in qualitative evaluation of the corrosion by the images obtained on the SEM, in semi-quantitative evaluation of chemical composition of the surface residue by SEM-EDS and the amount of ions released in saliva on evaluation of atomic absorption spectrophotometry. RESULTS: The results showed that the pure titanium brackets and the ones with low nickel concentration were superior regarding resistance to corrosion. The cobalt-chromium alloy showed the greatest corrosion. In the presence of fluoride, it was observed greater variation in all alloys, especially in the ones of NiTi coated steel and the ones of cobalt-chromium. CONCLUSION: Although observed corrosion on the SEM, the spectrophotometry showed low ions release in the artificial saliva, however, the presence of fluoride negatively affected the corrosion resistance.

Mônica Pereira, Saporeti; Enio Tonani, Mazzieiro; Wisley Falcco, Sales.

2012-12-01

79

The effect of surface treatment with Er: YAG laser on shear bond strength of orthodontic brackets to fiber-reinforced composite  

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Objectives: This study aimed to investigate the effect of surface treatment with Er:YAG laser on shear bond strength (SBS) of orthodontic brackets to fiber-reinforced composite (FRC). Study Design: Ninety human premolars were randomly divided into six groups of 15. FRC bars were bonded to the teeth with a flowable composite (FC) and then underwent following treatments. In group 1 no further treatment was performed. In group 2 the FRC surfaces were covered by FC. An Er:YAG laser was employed to treat FRCs in groups 3 ( 200 mJ/10 Hz) and 4 (300 mJ/15 Hz). The FRC strips in groups 5 and 6 were first covered by FC and then irradiated with Er:YAG laser at 200 mJ/10 Hz (group 5) or 300 mJ/15 Hz (group 6). Stainless steel brackets were bonded to FRCs using a light-cure adhesive system. After 24 hours, the samples were tested for SBS and the adhesive remnant index (ARI) scores were determined. Results: There was a significant difference in SBS among the study groups (P reinforced composite, orthodontics, Sshear bond strength, laser, Er:YAG, surface treatment, bracket, FRC. PMID:25593660

Dehghani, Mahboobe

2014-01-01

80

The role of friction in orthodontics  

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Full Text Available INTRODUCTION: Sliding mechanics is widely used during orthodontic treatment. One of the disadvantages of this mechanics is the friction generated at the bracket/archwire interface, which may reduce the amount of desired orthodontic movement obtained. Due to the application and great acceptance of this type of mechanics, the role of friction in Orthodontics has been of interest for both clinicians and scientists. OBJECTIVE: Therefore, this article discussed how friction affects orthodontic tooth movement, with an approach to its clinical implications as well as the evolution of dental materials and its properties regarding resistance to sliding.

Mariana Ribeiro Pacheco

2012-04-01

81

Influence of CO2 (10.6 ?m) and Nd:YAG laser irradiation on the prevention of enamel caries around orthodontic brackets.  

Science.gov (United States)

One possible undesirable consequence of orthodontic therapy is the development of incipient caries lesions of enamel around brackets. The aim of this study was to compare the effects of CO2 (??=?10.6 ?m) and Nd:YAG (??=?1,064 nm) lasers associated or not with topical fluoride application on the prevention of caries lesions around brackets. Brackets were bonded to the enamel of 65 premolars. The experimental groups (n?=?13) were: G1-application of 1.23 % acidulated fluoride phosphate gel (AFP, control); G2-Nd:YAG laser irradiation (0.6 W, 84.9 J/cm(2), 10 Hz, 110 ?s, contact mode); G3-Nd:YAG laser irradiation associated with AFP; G4-CO2 laser irradiation (0.5 W, 28.6 J/cm(2), 50 Hz, 5 ?s, and 10 mm focal distance); and G5-CO2 laser irradiation associated with AFP. Quantitative light-induced fluorescence was used to assess enamel demineralization. The data were statistically compared (??=?5 %). The highest demineralization occurred in the Nd:YAG laser group (G2, 26.15 %?±?1.94). The demineralization of all other groups was similar to that of the control group. In conclusion, CO2 laser alone was able to control enamel demineralization around brackets at the same level as that obtained with topical fluoride application. PMID:23812850

Seino, Priscila Yumi; Freitas, Patrícia Moreira; Marques, Márcia Martins; de Souza Almeida, Fernanda Campos; Botta, Sérgio Brossi; Moreira, Maria Stella Nunes Araújo

2015-02-01

82

Effect of self-etching primer/adhesive and conventional bonding on the shear bond strength in metallic and ceramic brackets  

OpenAIRE

Introduction: Bracket debonding from the tooth surface is a common problem in fixed orthodontics. The aims of the present study were to assess the bond strength and failure sites in two ways of bonding technique, with metallic and ceramic brackets. Material and Methods: One hundred premolars were assigned to 4 groups of 25 each: Group A, metallic brackets/ conventional procedure; Group B, metallic brackets/Transbond XT; Group C, ceramic brackets/conventional procedure; and Grou...

Mirzakouchaki, Behnam; Kimyai, Soodabeh; Hydari, Mahboubeh; Shahrbaf, Shirin; Mirzakouchaki-boroujeni, Parvin

2012-01-01

83

Prototype of a new tip developed to be coupled to dental light-curing units for optimizing bonding of orthodontic brackets and accessories  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: desenvolver uma nova ponteira para ser acoplada aos aparelhos fotopolimerizadores utilizados para colagem de braquetes e acessórios ortodônticos, e testar sua da efetividade em ensaio mecânico in vitro. A ponteira é espelhada na superfície interna e baseia-se em conceitos físicos de refraç [...] ão e reflexão de luz. Apresenta como principal vantagem o menor tempo clínico durante o procedimento de colagem, reduzindo a possibilidade de contaminação durante o processo. MÉTODOS: por meio de ensaio de resistência ao cisalhamento e determinação do índice remanescente de adesivo (IRA), testou-se a ponteira desenvolvida em 120 corpos de prova. A amostra foi dividia em dois grupos. No grupo 1, foi utilizado aparelho fotopolimerizador de fonte de luz halógena e, no grupo 2, fonte de LED. Cada grupo foi subdividido. Nos subgrupos H1 e L1, utilizou-se a ponteira convencional. Nos subgrupos H2 e L2 a colagem foi feita utilizando a ponteira desenvolvida para a polimerização do material de colagem. RESULTADOS: os valores dos testes de cisalhamento e IRA para os subgrupos foram comparados entre si. Os resultados mostraram que não houve diferença estatisticamente significativa para o ensaio de resistência ao cisalhamento (p > 0,05) nem para o IRA (p > 0,05) entre os subgrupos. CONCLUSÃO: os testes de ensaio mecânico, assim como a análise do IRA, mostraram que a nova ponteira desenvolvida cumpriu os requisitos necessários à colagem dos acessórios ortodônticos, e que o tempo de colagem foi reduzido pela metade, sendo necessária uma só incidência. Abstract in english OBJECTIVE: development of a new device to be coupled to light-curing units for bonding orthodontic brackets and accessories, and test its efficacy in an in vitro mechanical trial. The inner surface of the device is mirrored and is based on physical concepts of light refraction and reflection. The ma [...] in advantage of such device is the reduced clinical time needed for bonding and the low possibility of contamination during the process. METHODS: One hundred and twenty specimens were used for testing the shear bond strength of brackets bonded with the device. The Adhesive Remnant Index (ARI) was also determined. The sample was divided into 2 groups. In group 1 a halogen light-curing unit was used while in group 2 a led light-curing unit was used. Each group was then subdivided. In subgroups H1 and L1, a conventional light guide rod was used while in subgroups H2 and L2 bonding was performed with the mirrored device coupled to the tip of the guide light rod. RESULTS: The values obtained for the shear bond strength and the ARI in the subgroups were compared. Results showed that there was no statistically significant difference for the shear strength (p > 0.05) and the ARI (p > 0.05) between the subgroups. CONCLUSION: The tests of mechanical trials and the ARI analysis showed that the new device fulfilled the requirements for bonding orthodontic accessories, and that the time for bonding was reduced to half, being necessary only one light exposure.

Sergio Luiz, Mota Júnior; Márcio José da Silva, Campos; Marco Abdo, Gravina; Marcelo Reis, Fraga; Robert Willer Farinazzo, Vitral.

2013-12-01

84

Evaluation of shear bond strength of orthodontic brackets bonded on the tooth surface after internal bleaching / Avaliação da resistência ao cisalhamento de briquettes ortodônticos colados na superfície dentária após clareamento interno  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Introdução : O apelo estético de pacientes que possuem dentes escurecidos é grande, pois atualmente os padrões estéticos se tornaram rigorosos e muitos pacientes antes ou durante o tratamento ortodôntico, realizam o procedimento de clareamento dental. Objetivo: Avaliar a adesão de braquetes or [...] todônticos em molares humanos que receberam clareamento interno. Material e método: Quarenta coroas de molares humanos foram divididas em quatro grupos, de acordo com o agente clareador utilizado: SP) perborato de sódio + água; SP) peróxido de carbamida; CP+SP) peróxido de carbamida + perborato de sódio; Cont) água (grupo controle). Os agentes clareadores colocados no interior das câmaras pulpares foram substituídos a cada 7 dias por 2 semanas, e a colagem dos braquetes foi efetuada após 30 dias do final do clareamento. O teste de resistência ao cisalhamento foi realizado em máquina de ensaios universal (Emic). Resultado: O teste estatístico ANOVA com nível de significância de 5% (p > 0,05), mostrou que não houve diferença estatística significante entre os grupos (p = 0,1214). Conclusão: Concluiu-se que os diferentes agentes clareadores estudados não interferem na resistência de adesão dos braquetes ao esmalte dentário e a colagem dos braquetes 30 dias após o clareamento interno é um procedimento seguro. Abstract in english Introduction: There is great demand for esthetic treatment by patients who have discolored teeth, because currently aesthetic standards have become stricter and many patients have tooth bleaching procedures performed before or during orthodontic treatment. Objective: To evaluate the bonding of [...] orthodontic brackets to human molars after internal tooth bleaching. Material and method: Forty molars were divided into four groups according to the bleaching agent used: PS) sodium perborate + water; PC) carbamide peroxide; PC + PS) carbamide peroxide + sodium perborate; Cont) water (control group). Bleaching agents placed inside the pulp chambers were replaced every 7 days for 2 weeks, and the brackets were bonded 30 days after the end of bleaching. The shear strength test was performed in a universal testing machine (Emic). Result: ANOVA with a significance level of 5% (p > 0.05), showed no statistically significant difference between groups (p = 0.1214). Conclusion: It was concluded that the different bleaching agents studied did not interfere with the bond strength of brackets to enamel and bonding the brackets 30 days after internal bleaching is a safe procedure.

Nadia de Souza, FERREIRA; Patrícia Campos Ferreira da, ROSA; Raffaela Di Iorio Jeronymo, FERREIRA; Marcia Carneiro, VALERA.

2014-06-01

85

Friction between different wire bracket combinations in artificial saliva: an in vitro evaluation  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: The objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment. MATERIAL AND METHODS: Stainless steel (SS and titanium-molybdenum alloy (TMA wires of 0.019x0.025-in diameter (American Orthodontics and polycarbonate bracket (American Orthodontics, ceramic bracket (American Orthodontics, and metal bracket (3M Unitek with slots of 0.022x0.030-in were used. The friction coefficient was assessed by means of mechanical traction with the system immersed in artificial saliva. The mean roughness of both wire surface and bracket slots was evaluated by using a surface profilometer. RESULTS: The system using TMA wire and polycarbonate bracket had the highest roughness (p<0.05. SS wire with ceramic bracket had the highest friction coefficient, whereas the use of metallic bracket yielded the lowest (p<0.05. However, it was observed a statistically significant difference in the system using TMA wire and ceramic bracket compared to that using TMA wire and polycarbonate bracket (p=0.038. CONCLUSIONS: Ceramic brackets in association with SS wire should be judiciously used, since this system showed a high friction coefficient.

Tatiana Kelly da Silva Fidalgo

2011-02-01

86

[The effect of autoclave sterilization on the surface properties of orthodontic brackets after fitting in the mouth].  

Science.gov (United States)

Repeated sterilizations of the orthodontic bands, after fitting in mouth, are likely to involve modifications of their surface properties. Through this study we have tried to observe the effect of sterilization by autoclave on the surface of the orthodontic bands, as well as the contribution of the use of ultrasound in the chain of sterilization. The sample was composed of 30 orthodontic bands divided into 5 groups: a group of new bands (witnesses) and 4 groups having undergone respectively 1 cycle, 3 cycles, 5 cycles and 7 cycles of autoclave sterilization according to the World Health Organization recommendations. For half of each group bands, ultrasonic cleaning has not been provided. The scanning electron microscopy with the elementary microanalysis by X-rays was used for the investigation of surface. At the exam, new bands showed surface irregularities probably due to manufacturing procedures. And the bands, without ultrasonic cleaning, showed the presence of contamination and discolourations. Moreover, there were no modifications on the surface of the bands cleaned by ultrasounds before sterilization. The presence of surface irregularities associated with deposits observed on the bands surface, may be the site of bio corrosion by contributing bio film accumulation. The stay duration of the orthodontic bands in mouth, during orthodontic treatment, is important. So the effect of sterilization on the surface of the orthodontic bands must encourage other scientific research to determine the long term effects of sterilization which remains an essential process in our daily practice. PMID:22457990

Rerhrhaye, W; Ouaki, B; Zaoui, F; Aalloula, E

2011-12-01

87

Friction between different wire bracket combinations in artificial saliva: an in vitro evaluation  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: The objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment. MATERIAL AND METHODS: Stainless steel (SS) and titanium-molybdenum alloy (TMA) wires of 0.019x0.025-in diameter (American Orth [...] odontics) and polycarbonate bracket (American Orthodontics), ceramic bracket (American Orthodontics), and metal bracket (3M Unitek) with slots of 0.022x0.030-in were used. The friction coefficient was assessed by means of mechanical traction with the system immersed in artificial saliva. The mean roughness of both wire surface and bracket slots was evaluated by using a surface profilometer. RESULTS: The system using TMA wire and polycarbonate bracket had the highest roughness (p

Tatiana Kelly da Silva, Fidalgo; Matheus Melo, Pithon; José Vinicius Bolognesi, Maciel; Ana Maria, Bolognese.

2011-02-01

88

Hypersensitivity to conventional and to nickel-free orthodontic brackets / Hipersensibilidade a bráquetes ortodônticos convencionais e a bráquetes "nickel-free"  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Este trabalho teve como objetivo avaliar a capacidade alergênica provocada pelos bráquetes ortodônticos, comparando a sensibilidade cutânea provocada pelos metais presentes nos bráquetes metálicos convencionais com a provocada por bráquetes com baixa concentração de níquel ("nickel-free"). A amostra [...] foi selecionada dos 400 pacientes em tratamento da clínica de Ortodontia da Pontifícia Universidade Católica de Minas Gerais (Belo Horizonte, MG, Brasil), no período compreendido entre o início de 2002 e o final de 2003. A amostra consistiu de 58 pacientes (30 homens e 28 mulheres), com idades variando de 11 a 30 anos, os quais eram portadores de aparelho ortodôntico fixo Morelli® em ambos os arcos. Estes pacientes foram diagnosticados quanto à sensibilidade ao níquel, por meio da aplicação do "patch test" com sulfato de níquel a 5%. Em uma segunda fase, trinta dias após o "patch test", comparou-se a sensibilidade cutânea provocada pelos metais presentes nos bráquetes convencionais e nos "Nickel Free", por meio de um teste de sensibilidade cutânea utilizando-se dois tipos de corpos-de-provas, em formato de disco, com a mesma composição destes bráquetes. A área de eleição para realização deste teste foi a parte interna do antebraço, sendo aplicados vinte corpos-de-prova de cada experimento (referente a uma boca completa de bráquetes). Dos 58 pacientes avaliados, 16 deles foram sensíveis ao "patch test" com sulfato de níquel a 5%. Dentre estes 16 pacientes, 12 deles desenvolveram reação alérgica ao Experimento 1 (corpo-de-prova com níquel), enquanto que no Experimento 2 (corpo-de-prova "Niquel Free") apenas 5 pacientes apresentaram sensibilidade a esta amostra. O teste de McNemar revelou que os corpos-de-prova "nickel-free" provocaram menor reação alérgica quando comparados aos convencionais (p = 0.016). Abstract in english The aim of this study was to evaluate the allergenic potential of orthodontic brackets, comparing the cutaneous sensitivity provoked by metals present in conventional metallic brackets to that provoked by brackets with a low concentration of nickel, known as "nickel-free". A sample was selected from [...] 400 patients undergoing treatment in the orthodontic clinic of the Pontifical Catholic University of Minas Gerais (Belo Horizonte, MG, Brazil), in the period from the beginning of 2002 to the end of 2003. A cutaneous sensitivity patch test containing 5% nickel sulphate was used in 58 patients (30 males and 28 females), aged between 11 and 30, which were using fixed appliances with Morelli® brackets in both arches. In a second phase, 30 days later, a comparative test of cutaneous sensitivity was applied to the whole sample with two types of test specimens, in the form of a disc. Two alloys were tested: discs composed of the alloy used in the construction of conventional brackets and discs composed of a nickel-free alloy. The internal part of the forearm was chosen for testing, and 20 test specimens of each experiment (corresponding to the twenty brackets of a complete fixed appliance) were applied. Of the 58 patients evaluated, 16 patients were sensitive to the patch test with 5% nickel sulphate. Out of these 16 patients, 12 developed an allergic reaction to experiment 1 (test specimen with nickel), while in experiment 2, only 5 patients showed sensitivity to that sample. The McNemar test revealed that the nickel-free test specimens provoked less allergic reaction when compared with the conventional alloy (p = 0.016).

Mariele Cristina Garcia, Pantuzo; Elton Gonçalves, Zenóbio; Helenice de Andrade, Marigo; Madelon Aparecida Fernandes, Zenóbio.

2007-12-01

89

Hypersensitivity to conventional and to nickel-free orthodontic brackets Hipersensibilidade a bráquetes ortodônticos convencionais e a bráquetes "nickel-free"  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this study was to evaluate the allergenic potential of orthodontic brackets, comparing the cutaneous sensitivity provoked by metals present in conventional metallic brackets to that provoked by brackets with a low concentration of nickel, known as "nickel-free". A sample was selected from 400 patients undergoing treatment in the orthodontic clinic of the Pontifical Catholic University of Minas Gerais (Belo Horizonte, MG, Brazil, in the period from the beginning of 2002 to the end of 2003. A cutaneous sensitivity patch test containing 5% nickel sulphate was used in 58 patients (30 males and 28 females, aged between 11 and 30, which were using fixed appliances with Morelli® brackets in both arches. In a second phase, 30 days later, a comparative test of cutaneous sensitivity was applied to the whole sample with two types of test specimens, in the form of a disc. Two alloys were tested: discs composed of the alloy used in the construction of conventional brackets and discs composed of a nickel-free alloy. The internal part of the forearm was chosen for testing, and 20 test specimens of each experiment (corresponding to the twenty brackets of a complete fixed appliance were applied. Of the 58 patients evaluated, 16 patients were sensitive to the patch test with 5% nickel sulphate. Out of these 16 patients, 12 developed an allergic reaction to experiment 1 (test specimen with nickel, while in experiment 2, only 5 patients showed sensitivity to that sample. The McNemar test revealed that the nickel-free test specimens provoked less allergic reaction when compared with the conventional alloy (p = 0.016.Este trabalho teve como objetivo avaliar a capacidade alergênica provocada pelos bráquetes ortodônticos, comparando a sensibilidade cutânea provocada pelos metais presentes nos bráquetes metálicos convencionais com a provocada por bráquetes com baixa concentração de níquel ("nickel-free". A amostra foi selecionada dos 400 pacientes em tratamento da clínica de Ortodontia da Pontifícia Universidade Católica de Minas Gerais (Belo Horizonte, MG, Brasil, no período compreendido entre o início de 2002 e o final de 2003. A amostra consistiu de 58 pacientes (30 homens e 28 mulheres, com idades variando de 11 a 30 anos, os quais eram portadores de aparelho ortodôntico fixo Morelli® em ambos os arcos. Estes pacientes foram diagnosticados quanto à sensibilidade ao níquel, por meio da aplicação do "patch test" com sulfato de níquel a 5%. Em uma segunda fase, trinta dias após o "patch test", comparou-se a sensibilidade cutânea provocada pelos metais presentes nos bráquetes convencionais e nos "Nickel Free", por meio de um teste de sensibilidade cutânea utilizando-se dois tipos de corpos-de-provas, em formato de disco, com a mesma composição destes bráquetes. A área de eleição para realização deste teste foi a parte interna do antebraço, sendo aplicados vinte corpos-de-prova de cada experimento (referente a uma boca completa de bráquetes. Dos 58 pacientes avaliados, 16 deles foram sensíveis ao "patch test" com sulfato de níquel a 5%. Dentre estes 16 pacientes, 12 deles desenvolveram reação alérgica ao Experimento 1 (corpo-de-prova com níquel, enquanto que no Experimento 2 (corpo-de-prova "Niquel Free" apenas 5 pacientes apresentaram sensibilidade a esta amostra. O teste de McNemar revelou que os corpos-de-prova "nickel-free" provocaram menor reação alérgica quando comparados aos convencionais (p = 0.016.

Mariele Cristina Garcia Pantuzo

2007-12-01

90

Fracture strength of different soldered and welded orthodontic joining configurations with and without filling material  

OpenAIRE

The aim of this study was to compare the mechanical strength of different joints made by conventional brazing, TIG and laser welding with and without filling material. Five standardized joining configurations of orthodontic wire in spring hard quality were used: round, cross, 3 mm length, 9 mm length and 7 mm to orthodontic band. The joints were made by five different methods: brazing, tungsten inert gas (TIG) and laser welding with and without filling material. For the original orthodontic w...

Jens Johannes Bock; Jacqueline Bailly; Christian Ralf Gernhardt; Robert Andreas Werner Fuhrmann

2008-01-01

91

Frictional resistance of self-ligating versus conventional brackets in different bracket-archwire-angle combinations  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Objective: To compare the influence of archwire material (NiTi, beta-Ti and stainless steel) and brackets design (self-ligating and conventional) on the frictional force resistance. Material and Methods: Two types of brackets (self-ligating brackets - Smartclip, 3M/Unitek - and conventional brack [...] ets - Gemini, 3M/Unitek) with three (0, 5, and 10 degrees) slot angulation attached with elastomeric ligatures (TP Orthodontics) were tested. All brackets were tested with archwire 0.019"x0.025" nickel-titanium, beta-titanium, and stainless steel (Unitek/3M). The mechanical testing was performed with a universal testing machine eMIC DL 10000 (eMIC Co, Brazil). The wires were pulled from the bracket slots at a cross-head speed of 3 mm/min until 2 mm displacement. Results: Self-ligating brackets produced significantly lower friction values compared with those of conventional brackets. Frictional force resistance values were directly proportional to the increase in the bracket/ wire angulation. With regard to conventional brackets, stainless steel wires had the lowest friction force values, followed by nickel-titanium and beta-titanium ones. With regard to self-ligating brackets, the nickel-titanium wires had the lowest friction values, significantly lower than those of other materials. Conclusion: even at different angulations, the self-ligating brackets showed significantly lower friction force values than the conventional brackets. Combined with nickel-titanium wires, the self-ligating brackets exhibit much lower friction, possibly due to the contact between nickel-titanium clips and wires of the same material.

Maria Regina Guerra, MONTEIRO; Licinio Esmeraldo da, SILVA; Carlos Nelson, ELIAS; Oswaldo de Vasconcellos, VILELLA.

2014-06-01

92

Effect of Fast Curing Lights, Argon Laser, and Plasma Arc on Bond Strengths of Orthodontic Brackets: An In Vitro Study  

OpenAIRE

Objective: Nowadays light-cured composites are used widely by orthodontists to bond brackets. As these composites require 20-40 seconds time per tooth to be light cured, more chair-time in needed compared to self-cured composites. In recent years, the argon laser and plasma arc lights have been introduced in dentistry to reduce this curing time. The purpose of this study was to compare bond strength of brackets bonded with the argon la-ser and plasma arc light with those bonded with the conve...

Hashem-hoseini, M.; Mahmood-hashemi, H.; Soltan-moradi, F.; Hooshmand, T.; Haririan, I.; Motahhary, P.; Chalipa, J.

2008-01-01

93

A bracket design proposal for the first molar  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction: The advent of bracket bonding simplified the assembly of orthodontic braces, besides giving more comfort to the patient and decreasing the risk of decalcification. However, there is no first molar bracket with accessory tube and hooks in the market, except for the convertible type.Objective:To present a patent for utility model of a bracket Roth prescription, Straight-Wire technique for first molar, in order to facilitate orthodontic treatment where there is a need for placing accessories in second molars.Material and methods:This patent consists of a molar bracket for bonding, which contains a retentive base for this, similar to the bracket used in the Edgewise technique,with fins for placing alastic or metal ligature,but containing pre-angles and torques as the tubes of the molar Straight-Wire technique with Roth prescription.It also includes an accessory tube for placing arches or cantilevers and hooks for placing elastics.Results and conclusion:With this bracket design proposal it is possible to obtain an accessory that facilitates the inclusion of the second molar in the assembly of the orthodontic brace without the use of bands.Moreover, this bracket has fins for placing ligatures,accessory tube for placing arches or cantilevers and hooks for placing elastics.

Roberto Scalon

2010-07-01

94

Orthodontic brackets removal under shear and tensile bond strength resistance tests – a comparative test between light sources  

International Nuclear Information System (INIS)

We have investigated if a new LEDs system has enough efficient energy to promote efficient shear and tensile bonding strength resistance under standardized tests. LEDs 470 ± 10 nm can be used to photocure composite during bracket fixation. Advantages considering resistance to tensile and shear bonding strength when these systems were used are necessary to justify their clinical use. Forty eight human extracted premolars teeth and two light sources were selected, one halogen lamp and a LEDs system. Brackets for premolar were bonded through composite resin. Samples were submitted to standardized tests. A comparison between used sources under shear bonding strength test, obtained similar results; however, tensile bonding test showed distinct results: a statistical difference at a level of 1% between exposure times (40 and 60 seconds) and even to an interaction between light source and exposure time. The best result was obtained with halogen lamp use by 60 seconds, even during re-bonding; however LEDs system can be used for bonding and re-bonding brackets if power density could be increased

95

[The materials engineering characteristics of orthodontic nickel-titanium wires].  

Science.gov (United States)

Since their introduction in 1971 nickel-titanium wires have been widely used in orthodontics. Today, there is a multitude of new NiTi-alloys, whose properties are described. Beside the memory effect, these alloys have particular elastic properties, which can be characterized by a low modulus of elasticity, excellent springback, and pseudoelasticity (superelasticity). These properties are a consequence of the fact that depending on temperature and mechanical stress NiTi-alloys have two crystalline structures: martensite and austenite. The transition between these two phases, called martensitic transformation, is responsible for the memory effect, where a one way and a two way effect can be distinguished. For orthodontic applications pseudoelasticity is regarded as a highly favourable property. Pseudoelastic behavior is caused by stress induced martensite. Analysing the elastic properties of the available wires two categories can be distinguished: "work hardened martensite" and "pseudoelastic alloy". The biocompatibility of NiTi is sufficient, it can be used as an implant material. PMID:2286345

Drescher, D; Bourauel, C; Thier, M

1990-12-01

96

Shear bond strength of orthodontic resins after caries infiltrant preconditioning  

OpenAIRE

OBJECTIVE: To investigate the influence of caries infiltrant preconditioning on the shear bond strength of orthodontic resin cements on sound and demineralized enamel. MATERIALS AND METHODS: Stainless-steel brackets were bonded to sound or artificially demineralized (14 d, acidic buffer, pH 5.0) bovine enamel specimens using a resin cement or a combination of caries infiltrant preconditioning (Icon, DMG) and the respective resin cement (light-curing composite: Heliosit Orthodontic, Transbo...

Naidu, Ewelina; Stawarczyk, Bogna; Tawakoli, Pune Nina; Attin, Rengin; Attin, Thomas; Wiegand, Annette

2012-01-01

97

Quantitative analysis of S. mutans and S. sobrinus cultivated independently and adhered to polished orthodontic composite resins  

OpenAIRE

In Orthodontics, fixed appliances placed in the oral cavity are colonized by microorganisms. OBJECTIVE: The purpose of this study was to quantitatively determine the independent bacterial colonization of S. mutans and S. sobrinus in orthodontic composite resins. MATERIAL AND METHODS: Seven orthodontic composite adhesives for bonding brackets were selected and classified into 14 groups; (GIm, GIs) Enlight, (GIIm, GIIs) Grengloo, (GIIIm, GIIIs) Kurasper F, (GIVm, GIVs) BeautyOrtho Bond, (GVm, G...

Ulises Velazquez-Enriquez; Rogelio Jose Scougall-Vilchis; Rosalia Contreras-Bulnes; Jaime Flores-Estrada; Shinsuke Uematsu; Ryozo Yamaguchi

2012-01-01

98

A comparative clinical study of the failure rate of orthodontic brackets bonded with two adhesive systems: conventional and self-etching primer (SEP)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o objetivo do presente estudo foi comparar o desempenho clínico da colagem de braquetes ortodônticos com resina Transbond (3M Unitek) associada a dois sistemas adesivos: convencional em duas etapas (ataque ácido + Transbond XT adhesive Primer) e Self-Etching Primer (SEP), em etapa única (T [...] ransbond Plus). MÉTODOS: a amostra foi constituída de 480 braquetes metálicos (Victory, 3M Unitek), colados em 24 pacientes, que foram tratados durante um período de 36 a 48 meses. A colagem foi feita por meio do sistema split-mouth, utilizando os dois sistemas de colagem em cada paciente. Foi analisada a taxa de queda dos braquetes para cada sistema de colagem, descrita a causa da queda conforme relato do paciente e a posição dos dentes nas arcadas. RESULTADOS: o sistema adesivo convencional apresentou taxa de queda de 5,41%, enquanto a do SEP foi de 4,58%. O sistema convencional apresentou 5 quedas (38,4%) no quadrante superior direito, 2 (15,4%) no quadrante superior esquerdo, 4 (30,8%) no quadrante inferior direito e 2 (15,4%) no quadrante inferior esquerdo. O SEP apresentou 4 quedas (36,4%) no quadrante superior direito, 1 (9%) no quadrante superior esquerdo, 3 (27,3%) no quadrante inferior direito e 3 (27,3%) no quadrante inferior esquerdo. Por meio da análise estatística descritiva e do teste Odds Ratio, constatou-se que não houve diferença significativa entre essas taxas (p = 0,67). CONCLUSÃO: com base nesses resultados, pode-se concluir que o sistema adesivo SEP apresentou eficácia clínica semelhante à do sistema adesivo convencional. Abstract in english OBJECTIVE: This study compared the clinical performance of orthodontic brackets bonded with Transbond adhesive paste after two priming systems: a two-stage conventional system (acid etching + Transbond XT adhesive primer) and a singlestage self-etching primer (SEP) (Transbond Plus). METHODS: The sam [...] ple comprised 480 metal brackets bonded to the teeth of 24 consecutive patients treated for 36 to 48 months. A split-mouth design was used for bonding, and both systems were used in each patient. Bracket failure rates for each system were analyzed; and failure causes as reported by the patients and the quadrant of teeth for which brackets failed were recorded. RESULTS: The conventional system group had a failure rate of 5.41%, whereas the rate for SEP was 4.58%. In this group, there were 5 failures (38.4%) in the right maxillary quadrant, 2 (15.4%) in the left maxillary quadrant, 4 (30.8%) in the right mandibular quadrant, and 2 (15.4%) in the left mandibular quadrant. In the SEP group, there were 4 (36.4%) failures in the right maxillary quadrant, 1 (9%) in the left maxillary quadrant, 3 (27.3%) in the right mandibular quadrant, and 3 (27.3%) in the left mandibular quadrant. Results of descriptive statistical analysis and odds ratio did not show any significant differences between rates (p = 0.67). CONCLUSION: The clinical efficiency of SEP was similar to that of the conventional system.

Gladys Cristina, Dominguez; André, Tortamano; Luiz Vicente de Moura, Lopes; Priscilla Campanatti Chibebe, Catharino; Camillo, Morea.

2013-04-01

99

O efeito do jateamento do esmalte na força de adesão na colagem de braquetes / The effect of air abrasion in enamel adhesion of orthodontic bracket  

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Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: o propósito deste estudo in vitro foi avaliar o efeito do jateamento com óxido de alumínio na adesão de braquetes ortodônticos e compará-lo à tradicional técnica de condicionamento ácido do esmalte. METODOLOGIA: foram utilizados 80 dentes bovinos distribuídos aleatoriamente entre quatro gr [...] upos, sendo que a superfície do esmalte foi tratada da seguinte maneira: grupo 1 (somente jateamento com óxido de alumínio), grupo 2 (profilaxia com pedra-pomes e condicionamento com ácido), grupo 3 (jateamento com óxido de alumínio e condicionamento ácido) e grupo 4 (somente condicionamento ácido). Após, foi aplicado sistema adesivo e o braquete colado com resina. Os corpos-de-prova foram submetidos ao teste de cisalhamento e análise do IAR. Aos resultados foram aplicados o teste de variância múltipla (ANOVA) e a comparação entre pares (Tukey). Para a análise do IAR foi aplicado o teste Qui-quadrado. RESULTADOS: o grupo 1 apresentou a menor resistência ao cisalhamento (3,6MPa) e o 3 a maior (13,27MPa). A análise Qui-quadrado do IAR demonstrou que o tratamento da superfície do esmalte tem influência sobre a quantidade de remanescente de resina sobre o esmalte e os grupos 3 e 4 apresentaram a maior quantidade de resina aderida. CONCLUSÕES: o jateamento de óxido de alumínio não deve ser o único procedimento utilizado no preparo da superfície do esmalte na colagem de braquetes, porém, quando associado ao condicionamento ácido, mostrou-se eficaz no aumento da retenção entre esmalte e resina. Novos estudos são necessários visando menor dano do esmalte e adesão satisfatória. Abstract in english AIM: The purpose of this study in vitro was to evaluate the effect of the air abrasion with Al-oxide in the adhesion of orthodontic brackets and compare with traditional technique of acid conditioning of the enamel. METHODS: Eighty bovine teeth distributed randomly between four groups had been used [...] and the surface of the enamel was prepared in the following way: group 1 (only air abrasion), group 2 (enamel pumiced and acid conditioning), group 3 (air abrasion and acid conditioning) and group 4 (only acid conditioning). After, adhesive system was applied and bracket was bonded with resin. Shear bond was assessed and analysis of the IAR was performed. Test of multiple variance (ANOVA) and the comparison between pairs had been applied (Tukey) on the results. For the analysis of the IAR the Qui-square test was applied. RESULTS: Group 1 presented the lowest shear strength (3,6MPa) and 3 the greater (13,27MPa). The Qui-square analysis of the IAR demonstrated that the treatment of the enamel surface has influence on the amount of resin remainder on the enamel and groups 3 and 4 had presented the biggest amount of adhered resin. CONCLUSIONS: The air abrasion doesn’t have to be the only procedure used in the preparation of the enamel surface in the brackets bonding, however, when associated to the acid conditioning it revealed efficient in adhesion increase. New studies are necessary aiming at lesser damage of the enamel and satisfactory adhesion.

Carla D' Agostini, Derech; Juliana da Silva, Pereira; Margareth Maria Gomes de, Souza.

2008-06-01

100

Scanning electron microscopic examination of enamel surface after fixed orthodontic treatment: In-vivo study  

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Full Text Available Introduction. Therapy with fixed orthodontic appliances starts with bracket bonding and ends with debonding of brackets, leaving enamel surface varied. Objective. The aim of this pilot study was to examine enamel surface before and after debonding of orthodontic brackets by the use of scanning electron microscopy (SEM. Methods. Epoxy replicas of four patients’ premolars indicated for therapy with fixed orthodontic appliances were made and brackets were bonded to their teeth with a different adhesives (Enlight, No-mix, Fuji Ortho LC and Heliosit Orthodontic (n=4. Two months later, brackets on premolars were debonded and amounts of adhesive left on the tooth surfaces and the bracket bases were evaluated with the adhesive remnant index (ARI. After resin removal, epoxy replicas were made and the surface of premolars was evaluated with the enamel surface index (ESI. All replicas of premolars (n=32 were prepared for SEM examination and compared under different magnifications. Tooth damage was estimated based on correlation between ARItooth and ESI. Results. Pearson’s ?2 test showed no significant differences between ARItooth and ARIbracket of four materials used. Nonparametric correlations showed significant differences between ARItooth and ARIbracket, ESI and ARItooth, and between ESI and ARIbracket. Increasing of ARItooth is followed with the descent of ARIbracket and the ascent of ESI. Multivariate regression analysis showed a significant correlation between ESI and ARItooth. Conclusion. Most bond failures took place at enamel-adhesive interface. ARItooth was a predictor to enamel surface damage. The type of material did not affect enamel surface damage.

Sessa Tijana

2012-01-01

101

Interferência dos diferentes glazeamentos na colagem de bráquetes ortodônticos em superfícies cerâmicas Effects of the different glazed ceramic surfaces on the bond of orthodontic brackets  

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Full Text Available Foram avaliadas diferentes formas de glazeamento da superfície de porcelana quanto à resistência ao cisalhamento de bráquetes metálicos colados com diferentes cimentos. Quarenta e dois corpos de prova de metalocerâmica foram confeccionados (2 controles e divididos em quatro grupos de acordo com o tipo de glazeamento, com camada extra de glaze (G ou auto-glazeados (AG, e o cimento utilizado, resina fotopolimerizável (r ou ionômero de vidro resinosos (i, formando os seguintes grupos: Gr, Gi, AGr e AGi com 10 corpos de prova cada grupo. Todas as superfícies dos corpos de prova receberam tratamento com ácido fosfórico 35% por 30 s seguidos de uma camada de silano. Quarenta bráquetes metálicos foram colados. Os corpos de prova foram submetidos a termociclagem e ao teste de resistência ao cisalhamento com uma máquina universal de ensaios mecânicos. Uma amostra de cada grupo após descolagem, remoção da resina e polimento, foi avaliado em microscópio eletrônico de varredura. O índice de fratura coesiva da porcelana foi também avaliado. Os resultados mostram valores acima da média aceitável na literatura para todos os grupos, sendo que o grupo AGr apresentou valor menor (10,38 MPa e estatisticamente significativo em relação aos demais. A análise no microscópio eletrônico de varredura mostrou que as superfícies, após polimento, não readquirem as características de antes da colagem, apesar de se apresentarem aceitáveis clinicamente. Houve fratura da porcelana em todos os grupos. Conclui-se que é possível se conseguir colagem adequada de bráquetes metálicos em superfícies metalocerâmicas auto-glazeadas e com camada extra de glaze, preservando-o, não necessitando reconhecer previamente a forma de glazeamento.Different glazing techniques for porcelain surface were evaluated in terms of shear bond strength of metallic brackets bonded with different cements. Forty-two metal-ceramic samples were made (2 controls and then divided into four groups according to type of glazing technique, either using extra glaze layer (G or self-glazing material (SG, and type of adhesive material, that is, self-curing resin (r or resin glass-ionomer cement (i, thus forming the following groups: Gr, Gi, SGr, and SGi with 10 samples each. The whole surface of all samples was treated with 35% phosphoric acid for 30 s, followed by application of silane layer. Forty metallic brackets were bonded. The samples were submitted to thermocycling process and shear bond strength test with a universal testing machine. After bracket debonding, removal of resin, and polishing, one sample from each group was evaluated with a scanning electron microscope (SEM. The index of cohesive porcelain fracture was also assessed. The results show that all the groups had, on average, values higher than those found in the literature, with AGr presenting the lowest value (10.38 MPa compared to other groups. SEM analysis showed that the porcelain surfaces did not recover their original characteristics before the bracket debonding procedure, although they were considered acceptable for clinical use. Porcelain fracture was observed in all groups. One can conclude that it is possible to bond metallic brackets adequately to metal-ceramic porcelain surfaces previously treated with either self-glazing material or extra glaze layer without having to recognise the glazing technique originally employed.

A. C Dalvi

2010-06-01

102

Interferência dos diferentes glazeamentos na colagem de bráquetes ortodônticos em superfícies cerâmicas / Effects of the different glazed ceramic surfaces on the bond of orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Foram avaliadas diferentes formas de glazeamento da superfície de porcelana quanto à resistência ao cisalhamento de bráquetes metálicos colados com diferentes cimentos. Quarenta e dois corpos de prova de metalocerâmica foram confeccionados (2 controles) e divididos em quatro grupos de acordo com o t [...] ipo de glazeamento, com camada extra de glaze (G) ou auto-glazeados (AG), e o cimento utilizado, resina fotopolimerizável (r) ou ionômero de vidro resinosos (i), formando os seguintes grupos: Gr, Gi, AGr e AGi com 10 corpos de prova cada grupo. Todas as superfícies dos corpos de prova receberam tratamento com ácido fosfórico 35% por 30 s seguidos de uma camada de silano. Quarenta bráquetes metálicos foram colados. Os corpos de prova foram submetidos a termociclagem e ao teste de resistência ao cisalhamento com uma máquina universal de ensaios mecânicos. Uma amostra de cada grupo após descolagem, remoção da resina e polimento, foi avaliado em microscópio eletrônico de varredura. O índice de fratura coesiva da porcelana foi também avaliado. Os resultados mostram valores acima da média aceitável na literatura para todos os grupos, sendo que o grupo AGr apresentou valor menor (10,38 MPa) e estatisticamente significativo em relação aos demais. A análise no microscópio eletrônico de varredura mostrou que as superfícies, após polimento, não readquirem as características de antes da colagem, apesar de se apresentarem aceitáveis clinicamente. Houve fratura da porcelana em todos os grupos. Conclui-se que é possível se conseguir colagem adequada de bráquetes metálicos em superfícies metalocerâmicas auto-glazeadas e com camada extra de glaze, preservando-o, não necessitando reconhecer previamente a forma de glazeamento. Abstract in english Different glazing techniques for porcelain surface were evaluated in terms of shear bond strength of metallic brackets bonded with different cements. Forty-two metal-ceramic samples were made (2 controls) and then divided into four groups according to type of glazing technique, either using extra gl [...] aze layer (G) or self-glazing material (SG), and type of adhesive material, that is, self-curing resin (r) or resin glass-ionomer cement (i), thus forming the following groups: Gr, Gi, SGr, and SGi with 10 samples each. The whole surface of all samples was treated with 35% phosphoric acid for 30 s, followed by application of silane layer. Forty metallic brackets were bonded. The samples were submitted to thermocycling process and shear bond strength test with a universal testing machine. After bracket debonding, removal of resin, and polishing, one sample from each group was evaluated with a scanning electron microscope (SEM). The index of cohesive porcelain fracture was also assessed. The results show that all the groups had, on average, values higher than those found in the literature, with AGr presenting the lowest value (10.38 MPa) compared to other groups. SEM analysis showed that the porcelain surfaces did not recover their original characteristics before the bracket debonding procedure, although they were considered acceptable for clinical use. Porcelain fracture was observed in all groups. One can conclude that it is possible to bond metallic brackets adequately to metal-ceramic porcelain surfaces previously treated with either self-glazing material or extra glaze layer without having to recognise the glazing technique originally employed.

A. C, Dalvi; A. M, Bolognese.

2010-06-01

103

Comparison of deformation and torque expression of the orthos and orthos Ti bracket systems.  

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Orthodontic torque expression is the result of axial rotation of rectangular archwires within a rectangular bracket slot. This study investigates the effect of bracket material on torque expression. Torque exerted by a rotating archwire on each bracket will be measured as well as the relative deformation of each bracket slot. A total of 60 tests were performed where archwires were rotated within a bracket slot to produce torque within a bracket. Thirty Ormco Orthos Ti and 30 Orthos SS were compared to investigate the effect of torque on bracket material. Each bracket was mounted on a six-axis load cell that measured forces and moments in all directions. The archwire was rotated from an initial angle of 0 degree in 3 degrees increments to maximum angle of 51 degrees and then returned to the initial position. An overhead camera took images at each 3 degrees increment. The bracket images were post-processed using a digital image correlation technique to measure the relative deformation of each bracket slot. The maximum torque expressed at 51 degrees was 99.8 Nmm and 93.0 Nmm for Orthos Ti and Orthos SS, respectively. Total plastic deformation measured at 0 degrees post-torquing of the Orthos SS was 0.038 mm compared to 0.013 mm for Orthos Ti. The Orthos Ti brackets plastically deformed less than the Orthos SS brackets after torquing. The Orthos SS bracket plastic deformation was 2.8 times greater than that of Orthos Ti brackets. The Orthos Ti brackets expressed more torque than the stainless steel brackets but exhibited substantial variation. PMID:22015820

Melenka, Garrett W; Lacoursiere, Ryan A; Carey, Jason P; Nobes, David S; Heo, Giseon; Major, Paul W

2014-08-01

104

Fracture strength of different soldered and welded orthodontic joining configurations with and without filling material.  

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The aim of this study was to compare the mechanical strength of different joints made by conventional brazing, TIG and laser welding with and without filling material. Five standardized joining configurations of orthodontic wire in spring hard quality were used: round, cross, 3 mm length, 9 mm length and 7 mm to orthodontic band. The joints were made by five different methods: brazing, tungsten inert gas (TIG) and laser welding with and without filling material. For the original orthodontic wire and for each kind of joint configuration or connecting method 10 specimens were carefully produced, totalizing 240. The fracture strengths were measured with a universal testing machine (Zwick 005). Data were analyzed by ANOVA (p=0.05) and Bonferroni post hoc test (p=0.05). In all cases, brazing joints were ruptured on a low level of fracture strength (186-407 N). Significant differences between brazing and TIG or laser welding (pwelding with filling material and 3 mm joint length (998 N). Using filling materials, there was a clear tendency to higher mean values of fracture strength in TIG and laser welding. However, statistically significant differences were found only in the 9-mm long joints (pwelded joints was positively influenced by the additional use of filling material. TIG welding was comparable to laser welding except for the impossibility of joining orthodontic wire with orthodontic band. PMID:19089229

Bock, Jens Johannes; Bailly, Jacqueline; Gernhardt, Christian Ralf; Fuhrmann, Robert Andreas Werner

2008-01-01

105

Comparison of the effect of hydrogel and solution forms of sodium ascorbate on orthodontic bracket-enamel shear bond strength immediately after bleaching: An in vitro study  

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Full Text Available Aim: This study compared the effects of hydrogel and solution forms of sodium ascorbate (SA with two different application times on bracket bond strength subsequent to bleaching. Materials and Methods: A total of 72 sound premolars were randomly divided into six groups (n = 12: An unbleached control group (group one and five experimental groups of carbamide peroxide. Specimens in group two were bonded immediately after bleaching; specimens in groups three and four were bleached, then treated with SA solution for ten minutes and three hours, respectively, and then bonded. In groups five and six, SA hydrogel was used and the specimens were prepared similar to groups three and four, respectively. Following debonding, bond strengths were recorded in MPa. To evaluate the amount of resin left on the enamel surfaces, adhesive remnant index (ARI scores were used. Statistical Analysis: The bond strength data were analyzed with ANOVA and pairwise comparisons were made by Tukey test. The ARI data were subjected to Kruskal-Wallis test and two-by-two comparisons were made by the Mann-Whitney U test. Results: There were significant differences in bond strengths between the groups ( P < 0.0005. However, the differences between groups three, four, five and six were not significant. Furthermore, there were no significant differences between group one and groups four and six, whereas the differences between the other groups were significant ( P < 0.05. Regarding ARI, there were significant differences among the groups ( P = 0.004. Conclusion: Bleaching significantly decreased the bracket bond strength. Compromised bonding was reversed with a three-hour application of both forms of SA.

Kimyai Soodabeh

2010-01-01

106

Application of particle-induced X-ray emission, backscattering spectrometry and scanning electron microscopy in the evaluation of orthodontic materials  

International Nuclear Information System (INIS)

The focus of this investigation was on orthodontic materials used in the manufacture of dental brackets. The properties of these dental materials are subjected to various physical parameters such as elongation, yield strength and elasticity that justify their application. In turn, these parameters depend on the quantitative elemental concentration distribution (QECD) in the materials used in the manufacture. For compositional analysis, proton-induced X-ray emission (PIXE), backscatter spectrometry (BS) and scanning electron microscopy (SEM) were applied. QECD analysis was performed to correlate the physical parameters with the composition and to quantify imperfections in the materials. PIXE and BS analyses were performed simultaneously with a 3 MeV proton beam while electrons accelerated at 25 keV were used for the SEM analysis. From the QECDs it was observed that: (1) the major elements Cr, Fe and Ni were homogeneously distributed in the orthodontic plate; (2) the distribution of Mo and O correlated with one another; (3) there was a spread of Cr around regions of high C concentration; and, (4) areas of high concentrations of Mo and O corresponded to a decrease in C concentrations. Elemental concentration correlations are shown to indicate the similarities and differences in the ease of formation of phases, based on the tangent of linearity. (author)

107

Fracture strength of different soldered and welded orthodontic joining configurations with and without filling material  

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Full Text Available The aim of this study was to compare the mechanical strength of different joints made by conventional brazing, TIG and laser welding with and without filling material. Five standardized joining configurations of orthodontic wire in spring hard quality were used: round, cross, 3 mm length, 9 mm length and 7 mm to orthodontic band. The joints were made by five different methods: brazing, tungsten inert gas (TIG and laser welding with and without filling material. For the original orthodontic wire and for each kind of joint configuration or connecting method 10 specimens were carefully produced, totalizing 240. The fracture strengths were measured with a universal testing machine (Zwick 005. Data were analyzed by ANOVA (p=0.05 and Bonferroni post hoc test (p=0.05. In all cases, brazing joints were ruptured on a low level of fracture strength (186-407 N. Significant differences between brazing and TIG or laser welding (p<0.05, Bonferroni post hoc test were found in each joint configuration. The highest fracture strength means were observed for laser welding with filling material and 3 mm joint length (998 N. Using filling materials, there was a clear tendency to higher mean values of fracture strength in TIG and laser welding. However, statistically significant differences were found only in the 9-mm long joints (p<0.05, Bonferroni post hoc test. In conclusion, the fracture strength of welded joints was positively influenced by the additional use of filling material. TIG welding was comparable to laser welding except for the impossibility of joining orthodontic wire with orthodontic band.

Jens Johannes Bock

2008-10-01

108

The role of friction in orthodontics  

OpenAIRE

INTRODUCTION: Sliding mechanics is widely used during orthodontic treatment. One of the disadvantages of this mechanics is the friction generated at the bracket/archwire interface, which may reduce the amount of desired orthodontic movement obtained. Due to the application and great acceptance of this type of mechanics, the role of friction in Orthodontics has been of interest for both clinicians and scientists. OBJECTIVE: Therefore, this article discussed how friction affects orthodontic too...

Mariana Ribeiro Pacheco; Wellington Corrêa Jansen; Dauro Douglas Oliveira

2012-01-01

109

Nanoparticles in orthodontics, a review of antimicrobial and anti-caries applications.  

Science.gov (United States)

Nanoparticles (NPs) are insoluble particles smaller than 100 nm in size. In order to prevent microbial adhesion or enamel demineralization in orthodontic therapy, two broad strategies have been used. These are incorporating certain NPs into orthodontic adhesives/cements or acrylic resins (nanofillers, silver, TiO2, SiO2, hydroxyapatite, fluorapatite, fluorohydroxyapatite) and coating surfaces of orthodontic appliances with NPs (i.e. coating bracket surfaces with a thin film of nitrogen-doped TiO2). Although the use of NPs in orthodontics can offer new possibilities, previous studies investigated the antimicrobial or physical characteristic over a short time span, i.e. 24 hours to a few weeks, and the limitations of in vitro studies should be recognized. Information on the long-term performance of orthodontic material using nanotechnology is lacking and necessitates further investigation and so do possible safety issues (toxicity), which can be related to the NP sizes. PMID:24325608

Borzabadi-Farahani, Ali; Borzabadi, Ebrahim; Lynch, Edward

2014-08-01

110

Evaluación in vitro de la resistencia friccional entre brackets cerámicos y arcos de acero inoxidable con y sin recubrimiento vítreo aplicado por el método Sol-Gel In vitro evaluation of frictional resistance between ceramic brackets and orthodontic steel wires with and without glass coatings applied by Sol-Gel method  

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Full Text Available INTRODUCCIÓN: comparar la resistencia friccional estática y dinámica in vitro entre brackets cerámicos y alambres de acero inoxidable con recubrimiento vítreo aplicado por el método Sol-Gel y sin él. MÉTODOS: se prepararon 58 alambres de acero inoxidable AISI 304 de 0.016 x 0.016 con recubrimiento vítreo aplicado por Sol-Gel y sin él. Posteriormente se evaluó la resistencia a la fricción estática y dinámica in vitro de los alambres sobre brackets cerámicos de zafiro monocristalino y se caracterizaron las superficies en contacto por microscopia óptica y electrónica de barrido (SEM. RESULTADOS: se encontraron diferencias estadísticamente significativas entre ambos grupos tanto para la fuerza de fricción estática (p = 0,000 como dinámica (p = 0,001. El grupo de los alambres recubiertos presentó una fuerza de fricción estática y dinámica mayor (estática: 1,78 ± 0,44 N, dinámica: 1,75 ± 0,49 N que el grupo sin recubrimientos (estática: 1,37 ± 0,31 N, dinámica: 1,41 ± 0,27 N. La caracterización por SEM mostró que se producen defectos superficiales en los recubrimientos después de las pruebas de fricción. CONCLUSIÓN: los recubrimientos evaluados no mostraron mejor comportamiento friccional sobre brackets de zafiro monocristalino cuando son comparados con el grupo control.INTRODUCTION: to compare the in vitro static and dynamic frictional resistance between ceramic brackets and stainless steel wires with and without glass coatings applied by sol-gel method. METHODS: 58 commercial stainless steel orthodontic wires AISI 304 (0.016 x 0.016 inch were prepared with and without vitreous coating applied by Sol- Gel method. The in vitro static and dynamic frictional resistance of the wires on the mono-crystalline ceramic brackets were evaluated; also, the wire surfaces were characterized by means of Optical Microscopy and scanning electronic microscopy (SEM. RESULTS: statistically significant differences were found between both groups under static (p = 0.000 as well as dynamic (p = 0.001 friction test. The friction values found in the coated group were higher (Static friction: 1.78 ± 0.44 N, Dynamic friction: 1.75 ± 0.49 N than the group with no coating (Static friction: 1.37 ± 0.31 N, Dynamic friction: 1.41 ± 0.27 N. Characterization by SEM showed surface defects in both groups after the friction tests. CONCLUSION: the evaluated coatings did not perform better in terms of frictional behavior on sapphire mono-crystalline ceramic brackets when compared with the control group.

Luz Adriana Rendón Arias

2008-12-01

111

Biocompatibilidade dos materiais em Ortodontia: mito ou realidade? Biocompatibility of orthodontic materials: myth or reality?  

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Full Text Available O objetivo deste trabalho é apresentar uma revisão sobre os conceitos relacionados à biocompatibilidade dos materiais empregados em Ortodontia. Fatos relacionados às reações de hipersensibilidade aos diversos materiais ortodônticos são discutidos, sendo apresentadas as condutas recomendáveis nestas situações.The aim of this paper is to present a review on the biocompatibility of orthodontic materials. Hypersensitivity reactions to these materials are discussed and the recommended conduct in this kind of situation are presented.

Luciane Macedo de Menezes

2009-04-01

112

An Indigenously Designed Apparatus for Measuring Orthodontic Force  

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Aim: An indigenous apparatus is designed to measure the orthodontic force delivered from elastomeric chains and compare this force with values obtained from the Instron universal testing machine. Material and Methods: An indigenously designed apparatus is developed to evaluate forces delivered by various orthodontic auxiliaries. The apparatus consists of a flat steel platform, movable arm, and a mounted screw gauge arm. Orthodontic brackets can be attached to these arms. An electric circuit is connected, to the movable arm, which will estimate the forces exerted between brackets with elastomeric chain. The circuit is connected to the signal conditioner which will display the reading. Elastomeric chain with four links is attached to the arms. The movable arm is adjusted to create orthodontic forces and calibrated on the digital displayer. Twenty Elastomeric chains are used and forces are calibrated with the indigenously designed apparatus. The values of the force is compared with the forces calibrated with Instron universal testing machine to compare the efficacy of the indigenous apparatus. Results: The force values obtained from activation of elastomeric chain segments, in the Instron universal testing machine and the indigenous apparatus were in the range of 100 to 150 grams, initially at 1mm activation then, took a steep rise to 300 to 350 grams at 5mm activation and then, had a gradual increase for the remaining 5mm activation, reaching 400 to 450 grams. Conclusion: The Indigenous apparatus can be considered efficient in measuring tensile force generated by orthodontic auxiliaries. PMID:24392423

Dinesh, S.P. Saravana; Arun, A.V.; Sundari, K.K. Shantha; Samantha, Christine; Ambika, K.

2013-01-01

113

Fracture strength of different soldered and welded orthodontic joining configurations with and without filling material  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this study was to compare the mechanical strength of different joints made by conventional brazing, TIG and laser welding with and without filling material. Five standardized joining configurations of orthodontic wire in spring hard quality were used: round, cross, 3 mm length, 9 mm lengt [...] h and 7 mm to orthodontic band. The joints were made by five different methods: brazing, tungsten inert gas (TIG) and laser welding with and without filling material. For the original orthodontic wire and for each kind of joint configuration or connecting method 10 specimens were carefully produced, totalizing 240. The fracture strengths were measured with a universal testing machine (Zwick 005). Data were analyzed by ANOVA (p=0.05) and Bonferroni post hoc test (p=0.05). In all cases, brazing joints were ruptured on a low level of fracture strength (186-407 N). Significant differences between brazing and TIG or laser welding (p

Jens Johannes, Bock; Jacqueline, Bailly; Christian Ralf, Gernhardt; Robert Andreas Werner, Fuhrmann.

2008-10-01

114

Tiedown Bracket  

Science.gov (United States)

Tiedown bracket secured to concrete slab with lag anchor and lag bolt. A trailer or other heavy equipment can be anchored by tethering it to strapping bolt. When bracket is no longer needed, it can be removed, leaving behind only lag anchor. Bracket is easily installed and removed without damage to concrete slab.

Mashburn, D.; Wald, J. E.; Helmsin, F. K.

1982-01-01

115

Influência do agente clareador peróxido de carbamida a 10% na resistência mecânica da colagem de braquetes ortodônticos Influence of 10% carbamide peroxide gel on the shear bond strength of orthodontic brackets  

Directory of Open Access Journals (Sweden)

Full Text Available O propósito deste estudo in vitro foi determinar a influência do agente clareador peróxido de carbamida a 10% na resistência mecânica da colagem de braquetes ortodônticos. Foram estudados três grupos denominados G1 (não submetido ao clareamento, G2 (com clareamento e colagem realizada 1 semana após e G3 (com clareamento e colagem realizada 24h após. O teste de cisalhamento foi conduzido na máquina de ensaios mecânicos Emic, com a velocidade de deformação de 0,5 mm/min.A resitência ao cisalhamento em relação à área de colagem foi calculada para cada dente e expressa em MPa. Os resultados mostraram aumento estatisticamente significante (pThe purpose of this in vitro study was to determine the influence of 10% carbamide peroxide gel on the shear bond strength of orthodontic brackets. Three group were studied: G1 (without bleaching, G2 (bleaching and bonding after 1 week and G3 (bleaching and bonding after 24h. The shear test was conduced in a Emic testing machine with a crosshead speed of 0,5 mm/min. The shear bond strength was calculated for each tooth and expressed in MPa. The results show enhance statistical significant (p<0,001 on the shear bond strength after bleaching and encreased with the time interval between bleaching and bonding, significantily.

Edgard Norões R. da Matta

2005-04-01

116

Influência do agente clareador peróxido de carbamida a 10% na resistência mecânica da colagem de braquetes ortodônticos / Influence of 10% carbamide peroxide gel on the shear bond strength of orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O propósito deste estudo in vitro foi determinar a influência do agente clareador peróxido de carbamida a 10% na resistência mecânica da colagem de braquetes ortodônticos. Foram estudados três grupos denominados G1 (não submetido ao clareamento), G2 (com clareamento e colagem realizada 1 semana após [...] ) e G3 (com clareamento e colagem realizada 24h após). O teste de cisalhamento foi conduzido na máquina de ensaios mecânicos Emic, com a velocidade de deformação de 0,5 mm/min.A resitência ao cisalhamento em relação à área de colagem foi calculada para cada dente e expressa em MPa. Os resultados mostraram aumento estatisticamente significante (p Abstract in english The purpose of this in vitro study was to determine the influence of 10% carbamide peroxide gel on the shear bond strength of orthodontic brackets. Three group were studied: G1 (without bleaching), G2 (bleaching and bonding after 1 week) and G3 (bleaching and bonding after 24h). The shear test was c [...] onduced in a Emic testing machine with a crosshead speed of 0,5 mm/min. The shear bond strength was calculated for each tooth and expressed in MPa. The results show enhance statistical significant (p

Edgard Norões R. da, Matta; José de Albuquerque Calasans, Maia; Orlando, Chevitarese.

2005-04-01

117

A study in vitro on radiation effects by Er:YAG laser combined with the fluorine therapy in the acid resistance of the dental enamel submitted to orthodontical brackets  

International Nuclear Information System (INIS)

Several researches have been demonstrating an increase in the resistance acid of the enamel surface when irradiated by some lasers types as Nd:YAG, C02, Er:YAG, and others, mainly when combined with the fluoride therapy after the irradiation of the laser. This study in vitro used the laser of Er:YAG which density of energy of 8.1 J/cm2 on the enamel about of orthodontical brackets of teeth extracted pre-molars. These teeth were then submitted to a rich way in S. mutans for twenty one days. The cases were analyzed: (1) enamel surface without any treatment, (2) enamel surface without any irradiation laser, but with therapy with acidulated phosphate fluoride, (3) enamel surface irradiated with laser of Er:YAG and (4) enamel surface irradiated by laser of Er:YAG and with application of acidulated phosphate fluoride. The results were analyzed through optical microscopy and scanning electron microscopy. The morphologic changes observed to the scanning electron microscopy suggest increase in the acid resistance of the enamel surface. However, to the optical microscopy, it was still possible to visualize undesirable white stains in the surface of the enamel. (author)

118

Shear bond strength of brackets to demineralize enamel after different pretreatment methods  

OpenAIRE

Objective: To compare the influence of demineralized and variously pretreated demineralized enamel on the shear bond strength of orthodontic brackets. Materials and Methods: Sixty bovine enamel specimens were allocated to five groups (n ?=? 12). Specimens of group 1 were not demineralized and were not pretreated, but served as controls. The other specimens were demineralized to form artificial carious lesions. Samples from group 2 were only demineralized and were kept untreated ...

Attin, R.; Stawarczyk, B.; Kec?ik, D.; Kno?sel, M.; Wiechmann, D.; Attin, T.

2012-01-01

119

Antimicrobial and fluoride release capacity of orthodontic bonding materials  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: The aim of this study was to evaluate the antimicrobial and fluoride releasing capacity of 3 bonding materials. MATERIAL AND METHODS: Thirty nine specimens with standardized surface smoothness and dimensions were prepared. The antimicrobial capacity of the materials against S. mutans, [...] L. casei and C. albicans was evaluated by determining the percentage of growth inhibition of these microorganisms in an inoculated medium, obtained by optical density readouts on a spectrophotometer. The potential to interfere in microbial growth on the surface of the studied materials was observed by means of scanning electron microscopy (SEM). The fluoride release capacity in ultrapure water for 14 days was analyzed by means of ion chromatography. RESULTS: The PLUS group presented the highest percentage of microbial inhibition and the most contamination-free surface. The FUJI group presented the best fluoride release capacity. CONCLUSIONS: The TransbondTM Plus Color Change was the one that presented the best general behavior considering the evaluated aspects.

Erika Machado, Caldeira; Amanda, Osorio; Edna Lucia Couto, Oberosler; Delmo Santiago, Vaitsman; Daniela Sales, Alviano; Matilde da Cunha Goncalves, Nojima.

2013-07-01

120

An ex vivo study of self-, light-, and dual-cured composites for orthodontic bonding.  

Science.gov (United States)

It was postulated that using a dual-cured composite to bond orthodontic brackets could result in bond strengths comparable with those of chemically-activated materials and higher than those for light-activated materials. The shear bond strength of four composite resins used to attach mesh-backed orthodontic brackets was measured at 24 hours and following mechanical insult in the ball-mill. Analysis of variance and an SNK range test showed that at 24 hours Dual-cured Porcelite gave a significantly higher mean bond strength than the other materials (P < 0.05). However, following ball-milling the mean bond strength for Right-on was apparently significantly higher than that of the other materials. (P < 0.05). In this study, the mode of bond failure is also analysed and the use of Weibull analysis in bond strength testing is described. PMID:8580097

Sargison, A E; McCabe, J F; Gordon, P H

1995-11-01

121

Avaliação da atividade antimicrobiana de adesivo ortodôntico associado a verniz de clorexidina e timol na colagem de braquetes Evaluation of antimicrobial activity of orthodontic adhesive associated with chlorhexidine-thymol varnish in bracket bonding  

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Full Text Available OBJETIVO: avaliar a atividade antimicrobiana da associação de um adesivo ortodôntico com um verniz de clorexidina e timol. MÉTODOS: foram utilizados 32 pré-molares humanos divididos em 4 grupos. O grupo 1 consistiu do grupo controle, no qual o adesivo utilizado para a colagem do braquete não estava associado a nenhum agente antimicrobiano. Os grupos 2, 3 e 4 foram colados com um sistema adesivo associado a um verniz de clorexidina e timol. Os grupos 3 e 4 foram armazenados em água por 7 dias e 30 dias, respectivamente, enquanto os corpos de prova do grupo 2 foram, logo depois da colagem, colocados em ágar semeado com Streptococcus mutans por 48h a 37ºC. RESULTADOS: os grupos experimentais, com exceção do grupo controle, apresentaram atividade antimicrobiana com tendência de redução do seu potencial de ação com maior tempo de imersão em água. CONCLUSÃO: a associação do verniz de clorexidina a um sistema adesivo utilizado em Ortodontia apresenta-se vantajosa pela sua atividade antimicrobiana.OBJECTIVE: To assess the antimicrobial activity resulting from the association of an orthodontic adhesive with chlorhexidine-thymol varnish. METHODS: Thirty-two extracted human premolars were used, divided into four groups. In Group 1, the control group, the adhesive used to bond the bracket was not associated with any antimicrobial agent. Groups 2, 3 and 4 were bonded with an adhesive system associated with chlorhexidine-thymol varnish. Groups 3 and 4 were stored in water for 7 days and 30 days, respectively, while the specimens from group 2 were, soon after bonding, placed on agar seeded with Streptococcus mutans for 48 hours, at 37º C. RESULTS: The experimental groups, with the exception of the control group, showed antimicrobial activity whose action tended to decline commensurately with the amount of time that they remained immersed in water. CONCLUSIONS: The association of chlorhexidine-thymol varnish with an adhesive system used in orthodontics proved to be advantageous due to its antimicrobial activity.

Carolina Freire de Carvalho Calabrich

2010-08-01

122

Influência do tempo pós-fixação na resistência ao cisalhamento de bráquetes colados com diferentes materiais Influence of post-fixation time on shear bond strength of brackets fixed with different bonding materials  

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Full Text Available Este estudo avaliou a resistência ao cisalhamento da união, nos tempos pós-fixação de 10 minutos e 24 horas, de quatro materiais para colagem de bráquetes e os tipos de falhas na fratura. Foram utilizados 64 pré-molares humanos recém-extraídos embutidos em resina. As faces vestibulares de 32 pré-molares foram condicionadas com ácido fosfórico a 35%, por 30 segundos e em 16 deles, os bráquetes foram colados com Concise Ortodôntico (3M e nos demais com resina composta Z100 (3M. Em 32 dentes, os bráquetes foram colados sem condicionamento do esmalte, com ionômeros de vidro Fuji I (GC e Fuji Ortho LC (GC. Após a fixação, 32 corpos-de-prova foram armazenados em água destilada a 37ºC, por 10 minutos e o restante por 24 horas e submetidos ao teste de cisalhamento numa máquina com velocidade de 0,5 mm/min. Os resultados submetidos à ANOVA e ao teste de Tukey (5% mostraram que os maiores valores de resistência ao cisalhamento aos 10 minutos e 24 horas foram observados com o Concise Ortodôntico, com diferença estatística significativa em relação ao Fuji Ortho LC, Z100 e Fuji I. Nenhuma diferença estatística foi observada entre Fuji Ortho LC, Z100 e Fuji I. Os autores concluíram que o Concise Ortodôntico apresentou maiores valores de resistência ao cisalhamento em relação aos outros materiais, nos tempos de 10 minutos e 24 horas, os valores obtidos no período de 24 horas foram superiores em relação aos de 10 minutos, para todos materiais e um grande número de falhas adesivas foi observada para o Fuji I, Concise Ortodôntico e Z100.The purpose of this study was to evaluate the shear bond strength of four bonding materials for brackets, 10 minutes and 24 hours after their fixation, as well as the kinds of fracture observed. The buccal surfaces of 32 premolars were etched for 30 seconds with 35% phosphoric acid, and brackets were bonded using Orthodontic Concise (3M and Z100 (3M. In other 32 premolars, brackets were bonded with Fuji I (GC and Fuji Ortho LC (GC on the buccal surfaces, without acid etching. After the bonding procedures, 32 samples were stored in distilled water at 37ºC for 10 minutes, and 32 samples were stored at the same temperature for 24 hours. The samples were then submitted to shear bond strength testing in an Instron testing machine, at a crosshead speed of 0.5 mm/min. The results were submitted to ANOVA and Tukey’s test (p < 0.05. The results indicated that, for 10 minutes and 24 hours, Orthodontic Concise showed shear bond strength values (6.22 and 7.73 MPa, respectively higher than Fuji Ortho LC (3.32 and 5.10 MPa, Z100 (2.72 and 4.51 MPa and Fuji I (2.52 and 4.54 MPa. No statistical difference was verified between Fuji Ortho LC, Z100 and Fuji I (p < 0.05. In conclusion, Orthodontic Concise showed better shear bond strength values than the other three bonding materials, for both 10-minute and 24-hour storage periods; the shear bond strength averages were higher for the storage time of 24 hours, for all tested materials, and a great number of adhesive fractures were observed in the specimens which received Fuji I, Orthodontic Concise and Z100.

Lourenço CORRER SOBRINHO

2002-03-01

123

Staining of esthetic brackets by plaque disclosing solutions  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english AIM: To evaluate the staining of esthetic orthodontic brackets by plaque disclosing solutions. METHODS: Two types of brackets manufactured by GAC/DENTSPLY(r) were evaluated: ceramic (n=30) and polycarbonate (n=30). The brackets were divided into 6 groups. Two control groups (n=6) were immersed [...] in absolute ethanol: GI - ceramic brackets and GII - polycarbonate brackets. Four experimental groups (n=12) were immersed in different plaque disclosing solutions: GIII (ceramic brackets) and GIV (polycarbonate brackets) were immersed in Replak(r); GV (ceramic brackets) and GVI (polycarbonate brackets) were immersed in Replasul "S"(r). Relative quantitative analysis of the influence of plaque disclosing tablets on bracket staining was performed using reflectance spectrophotometry of stain deposition. Exploratory analysis of the data was performed using Analysis of Variance (ANOVA) in a 2x2 factorial setup (bracket x immersion) with additional treatments (controls). RESULTS: The results demonstrated that the ceramic brackets presented the highest amount of staining when Replasul "S"(r) was used (pd"0.05). However, when Replak(r) was used, no statistically significant difference was found in comparison with the control group (p>0.05). For polycarbonate brackets, staining was detected for both disclosing solutions (p>0.05). CONCLUSIONS: The disclosing solutions caused stain formation on polycarbonate brackets and, under the tested conditions, use of Replak(r) on ceramic brackets did not cause staining.

Luiza Novelino Acatauassú, Ismael; Mauro de Amorim Acatauassú, Nunes; Ana Maria Novelino Acatauassú, Nunes; Rogério Heládio Lopes, Motta; Ana Paula Dias, Demasi; Flávia Martão, Flório.

2014-04-01

124

Effect of self-etching primer/adhesive and conventional bonding on the shear bond strength in metallic and ceramic brackets  

Science.gov (United States)

Introduction: Bracket debonding from the tooth surface is a common problem in fixed orthodontics. The aims of the present study were to assess the bond strength and failure sites in two ways of bonding technique, with metallic and ceramic brackets. Material and Methods: One hundred premolars were assigned to 4 groups of 25 each: Group A, metallic brackets/ conventional procedure; Group B, metallic brackets/Transbond XT; Group C, ceramic brackets/conventional procedure; and Group D, ceramic brackets/Transbond XT. Transbond XT composite paste was used for bracket bonding and cured by conventional light-cure device. Specimens were subjected to thermocycling. One week after bonding shearing force was applied to the bracket-tooth interface. Bonding failure site optically examined using a stereomicroscope under 10 × magnifications and scoring was done using the adhesive remnant index (ARI). Data were subjected to analysis of One-way variance, Tukey post hoc, Chi-square and Spearman’s tests. Results: Mean bond strength (in MPa) were: group A=9.2, group B=8.5, group C=6.2 and group D=5.7. Bond strength differences between groups A and B, and between C and D were not significant, (p<0.0005). Insignificant difference found in ARI in all groups. Conclusion: The bond strengths of metallic brackets were significantly higher than ceramic ones and the selfetching primer produce fewer bonds than the conventional method (clinically acceptable). A positive correlation found between changes in shearing bond strength and ARI. Key words: Acid etching, adhesive remnant index, orthodontic brackets, self-etching primer, shearing bond strength. PMID:21743430

Kimyai, Soodabeh; Hydari, Mahboubeh; Shahrbaf, Shirin; Mirzakouchaki-Boroujeni, Parvin

2012-01-01

125

Comparative evaluation of ceramic bracket base designs.  

Science.gov (United States)

Since the initial introduction of ceramic brackets, base designs have been modified to reduce tooth damage during debonding. The purpose of this study was to compare shear and tensile bond strengths and fracture sites of four second-generation ceramic brackets: Allure IV (A) (GAC International, Inc., Central Islip, N.Y.), Ceramaflex (C) (TP Orthodontics, Inc., LaPorte, Ind.), Intrigue (I) (Lancer Orthodontics, Carlsbad, Calif.), Transcend 2000 (T) (Unitek Corp., Monrovia, Calif.), and a foil-mesh base stainless steel bracket, DynaBond II (D) (Unitek Corp., Monrovia, Calif.). Twenty brackets of each type were bonded to 100 mandibular bovine incisor teeth with Concise bonding adhesive. The samples were thermocycled for 24 hours and the brackets were debonded with an Instron universal testing machine (Instron Corp., Canton, Mass.). A modified Transcend debonding instrument was used for tensile debonding, whereas a chisel was used for shear debonding. An analysis of variance was performed with a 0.05 level of confidence. Mean shear strengths (kg/cm2) necessary to debond were 174.0 (A), 71.0 (C), 189.0 (I), 228.0 (T), and 160.0 (D). Mean tensile strengths (kg/cm2) were 27.0 (A), 26.7 (C), 51.3 (I), 56.5 (T), and 48.6 (D). Fracture sites examined with a light microscope showed no enamel damage with any of the ceramic brackets. Intrigue was the only bracket to fracture and had 30% bracket fracture in the tensile mode and 20% bracket fracture in the shear mode. The percentage of fractures at the adhesive-bracket base interface for shear and tensile modes, respectively, were 80, 100 (A); 100, 90 (C); 10, 60 (I); 60, 90 (T); and 90, 80 (D).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8198079

Bordeaux, J M; Moore, R N; Bagby, M D

1994-06-01

126

Experiense with remineraling means in patients undergoing orthodontic treatment  

Directory of Open Access Journals (Sweden)

Full Text Available In patients undergoing orthodontic treatment using bracket-technology a high risk of caries development. The algorithm of preventive interventions for the prevention of hair demineralization of enamel of the teeth

Stepanova Ye.A.

2011-03-01

127

Stomatitis or systemically-induced contact dermatitis from metal wire in orthodontic materials.  

Science.gov (United States)

5 patients with dermatitis or stomatitis related to the use of orthodontic appliances are described. All the patients were patch tested with the European standard series. One had a ++ reaction to potassium dichromate, one a ++ reaction to nickel, and the remaining 3 no positive patch tests. 3 of the patients had recurrent vesicular hand eczema, which flared after oral challenge with 1 of the metals used in their orthodontic appliances. 2 of these 3 patients had negative patch tests. The dermatitis of 4 of the 5 patients cleared completely upon the removal of their metal orthodontic appliances or their replacement with appliances made of acrylics. PMID:8033545

Veien, N K; Borchorst, E; Hattel, T; Laurberg, G

1994-04-01

128

Esthetic orthodontic considerations for the adult patient: a general dentist's perspective.  

Science.gov (United States)

Esthetic orthodontics is a viable treatment option for patients seeking cosmetic enhancement. Today, the use of preadjusted orthodontic brackets and straight wire allow general dentists to create optimum esthetic results in a short period of time. Two cases are presented to demonstrate a clinical technique to enhance a patient's smile through adjunctive orthodontic therapy. PMID:10321200

Brooks, S A; Polk, M

1998-01-01

129

Orthodontics: Braces and More  

Science.gov (United States)

Orthodontics: Braces and More What Is Orthodontics? Why Seek Orthodontic Care? Who Can Benefit From Orthodontic Care? Types of Bad Bites Treatment: Braces and Retainers Risks and Limitations of Orthodontic Care ...

130

The accuracy of brackets placement in direct bonding technique: a comparison between the pole-like bracket positioning gauge and the star-like bracket positioning gauge  

Directory of Open Access Journals (Sweden)

Full Text Available The accuracy of brackets placement is a key factor in successful orthodontic therapy. An in vitro study was conducted in ten models from a natural maxillary teeth model in order to compare the accuracy of brac- kets placement between two direct bonding instru- ments: the Pole-like Bracket Positioning Gauge and the Star-like Bracket Positioning Gauge. Our results have shown that: The Star-like Bracket Positioning Gauge is more precise in placing brackets vertically, whereas the Pole-like Bracket Positioning Gauge al-lows a better angulation of the bracket. Considering each tooth separately, there is no statistically signifi-cant difference between the two positioning gauges, except that the Star-like gauge gives better results in bracket’s height for the second premolar and the ca-nine, whereas the Pole-like gauge allows for a better positioning and a better vertical angulation of the brackets for the lateral incisor. No statistically signi- ficant difference was found between the two gauges on the mesiodistal position. Overall, the Star-like gau- ge showed a better accuracy in positioning brackets.

Lahcen Ousehal

2011-12-01

131

Influence of lingual bracket position on microbial and periodontal parameters in vivo  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: Lingual orthodontics is becoming more popular in dental practice. The purpose of the present investigation was to compare plaque formation on teeth bonded with the same bracket onto buccal or lingual surface, with non-bonded control teeth, via an in vivo growth experiment over a 30-day pe [...] riod. MATERIAL AND METHODS: A randomized controlled trial with split-mouth design was set up enrolling 20 dental students. Within each subject sites with buccal and lingual brackets and control sites were followed. Clinical periodontal parameters (periodontal pocket depth: PPD; bleeding on probing: BOP) were recorded at baseline and on days 1, 7 and 30. Microbiological samples were taken from the brackets and the teeth on days 1, 7 and 30 to detect colony-forming units (CFU). Total CFU, streptococci CFU and anaerobe CFU were measured. RESULTS: No significant differences (P>0.05) were found between buccal and lingual brackets in terms of clinical periodontal parameters and microbiological values. Conclusion: Bracket position does not have significant impact on bacterial load and on periodontal parameters.

Maria Francesca, Sfondrini; Maurizia, Debiaggi; Francesca, Zara; Roberto, Brerra; Mario, Comelli; Marco, Bianchi; Sara Ramella, Pollone; Andrea, Scribante.

2012-06-01

132

Analysis of mesiodistal angulations of preadjusted brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Manufacturers offer various prescriptions of preadjusted brackets for use in the “straight-wire” orthodontic technique. However, the need to incorporate bends in the rectangular wires during orthodontic finishing has led to concerns regarding the type of prescription chosen and the credibility of in [...] formation provided by the manufacturer. The aim of this study was to compare the slot angulations of Roth prescription preadjusted metallic brackets for the maxillary left central incisor and maxillary left canine. For each tooth type, 10 brackets of three commercial brands (GAC, Forestadent and Morelli) were selected. Two individual metal matrices for brackets and tooth positioning were made for each group of teeth. Captured images were obtained by standardized ortho-radial photography with a digital camera. Images were exported and analyzed with the Image J software package. One-way ANOVA and Tukey statistical analyses were performed at the 5% significance level. For brackets of the maxillary left central incisor, differences in mean angulation were observed between the Morelli and GAC groups (p

Marcos Rogério de, MENDONÇA; Ana Caroline Gonçales, VERRI; Aubrey Fernando, FABRE; Osmar Aparecido, CUOGHI.

2014-08-21

133

Evaluation of failure characteristics and bond strength after ceramic and polycarbonate bracket debonding: effect of bracket base silanization.  

Science.gov (United States)

The objectives of this study were to evaluate the effect of silanization on the failure type and shear-peel bond strength (SBS) of ceramic and polycarbonate brackets, and to determine the type of failure when debonded with either a universal testing machine or orthodontic pliers. Silanized and non-silanized ceramic and polycarbonate brackets (N = 48, n = 24 per bracket type) were bonded to extracted caries-free human maxillary central incisors using an alignment apparatus under a weight of 750 g. All bonded specimens were thermocycled 1000 times (5-55 degrees C). Half of the specimens from each group were debonded with a universal testing machine (1 mm/minute) to determine the SBS and the other half by an operator using orthodontic debonding pliers. Failure types of the enamel surface and the bracket base were identified both from visual inspection and digital photographs using the adhesive remnant index (ARI) and base remnant index (BRI). As-received ceramic brackets showed significantly higher bond strength values (11.5 +/- 4.1 MPa) than polycarbonate brackets [6.3 +/- 2.7 MPa; (P = 0.0077; analysis of variance (ANOVA)]. Interaction between bracket types and silanization was not significant (P = 0.4408). Silanization did not significantly improve the mean SBS results either for the ceramic or polycarbonate brackets (12.9 +/- 3.7 and 6.3 +/- 2.7 MPa, respectively; P = 0.4044; two-way ANOVA, Tukey-Kramer adjustment). There was a significant difference between groups in ARI scores for ceramic (P = 0.0991) but not polycarbonate (P = 0.3916; Kruskall-Wallis) brackets. BRI values did not vary significantly for ceramic (P = 0.1476) or polycarbonate (P = 0.0227) brackets. Failure type was not significantly different when brackets were debonded with a universal testing machine or with orthodontic debonding pliers. No enamel damage was observed in any of the groups. PMID:18209212

Ozcan, M; Finnema, K; Ybema, A

2008-04-01

134

Influência do tempo pós-fixação na resistência ao cisalhamento de bráquetes colados com diferentes materiais / Influence of post-fixation time on shear bond strength of brackets fixed with different bonding materials  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este estudo avaliou a resistência ao cisalhamento da união, nos tempos pós-fixação de 10 minutos e 24 horas, de quatro materiais para colagem de bráquetes e os tipos de falhas na fratura. Foram utilizados 64 pré-molares humanos recém-extraídos embutidos em resina. As faces vestibulares de 32 pré-mol [...] ares foram condicionadas com ácido fosfórico a 35%, por 30 segundos e em 16 deles, os bráquetes foram colados com Concise Ortodôntico (3M) e nos demais com resina composta Z100 (3M). Em 32 dentes, os bráquetes foram colados sem condicionamento do esmalte, com ionômeros de vidro Fuji I (GC) e Fuji Ortho LC (GC). Após a fixação, 32 corpos-de-prova foram armazenados em água destilada a 37ºC, por 10 minutos e o restante por 24 horas e submetidos ao teste de cisalhamento numa máquina com velocidade de 0,5 mm/min. Os resultados submetidos à ANOVA e ao teste de Tukey (5%) mostraram que os maiores valores de resistência ao cisalhamento aos 10 minutos e 24 horas foram observados com o Concise Ortodôntico, com diferença estatística significativa em relação ao Fuji Ortho LC, Z100 e Fuji I. Nenhuma diferença estatística foi observada entre Fuji Ortho LC, Z100 e Fuji I. Os autores concluíram que o Concise Ortodôntico apresentou maiores valores de resistência ao cisalhamento em relação aos outros materiais, nos tempos de 10 minutos e 24 horas, os valores obtidos no período de 24 horas foram superiores em relação aos de 10 minutos, para todos materiais e um grande número de falhas adesivas foi observada para o Fuji I, Concise Ortodôntico e Z100. Abstract in english The purpose of this study was to evaluate the shear bond strength of four bonding materials for brackets, 10 minutes and 24 hours after their fixation, as well as the kinds of fracture observed. The buccal surfaces of 32 premolars were etched for 30 seconds with 35% phosphoric acid, and brackets wer [...] e bonded using Orthodontic Concise (3M) and Z100 (3M). In other 32 premolars, brackets were bonded with Fuji I (GC) and Fuji Ortho LC (GC) on the buccal surfaces, without acid etching. After the bonding procedures, 32 samples were stored in distilled water at 37ºC for 10 minutes, and 32 samples were stored at the same temperature for 24 hours. The samples were then submitted to shear bond strength testing in an Instron testing machine, at a crosshead speed of 0.5 mm/min. The results were submitted to ANOVA and Tukey’s test (p

Lourenço, CORRER SOBRINHO; Gisele Maria, CORRER; Simonides, CONSANI; Mário Alexandre Coelho, SINHORETI; Rafael Leonardo Xediek, CONSANI.

2002-03-01

135

[Developments in fixed orthodontic appliances].  

Science.gov (United States)

The Edgewise system and the Begg technique were until the early 1970's two of the most familiar and well-known fixed appliance techniques in orthodontics. During the following years they both underwent some slight adaptations that were generally based on more straightforward biomechanics. These changes have led to what in recent years is called the 'Straight Wire technique'. The latter claims to be the treatment option of choice based on preadjusted appliances and preformed arch wires. Besides biomechanics, treatment tools also concentrated on esthetics. It resulted in the development of smaller brackets as well as tooth coloured ones made from polycarbonates or ceramics. Finally lingual orthodontics starts to play a more important role in the orthodontic treatment options for the new millennium. PMID:11382972

Willems, G; Carels, C E

2000-04-01

136

Evaluation of friction of stainless steel and esthetic self-ligating brackets in various bracket-archwire combinations.  

Science.gov (United States)

This study measured and compared the level of frictional resistance generated between stainless steel self-ligating brackets (Damon SL II, SDS Ormco, Glendora, Calif), polycarbonate self-ligating brackets (Oyster, Gestenco International, Göthenburg, Sweden), and conventional stainless steel brackets (Victory Series, 3M Unitek, Monrovia, Calif), and 3 different orthodontic wire alloys: stainless steel (Stainless Steel, SDS Ormco), nickel-titanium (Ni-Ti, SDS Ormco), and beta-titanium (TMA, SDS Ormco). All brackets had a.022-in slot, whereas the orthodontic wire alloys were tested in 3 different sections:.016,.017 x.025, and.019 x 0.025 in. Each of the 27 bracket and archwire combinations was tested 10 times, and each test was performed with a new bracket-wire sample. Both static and kinetic friction were measured on a custom-designed apparatus. All data were statistically analyzed (Kruskal-Wallis and Mann Whitney U tests). Stainless steel self-ligating brackets generated significantly lower static and kinetic frictional forces than both conventional stainless steel and polycarbonate self-ligating brackets, which showed no significant differences between them. Beta-titanium archwires had higher frictional resistances than stainless steel and nickel-titanium archwires. No significant differences were found between stainless steel and nickel-titanium archwires. All brackets showed higher static and kinetic frictional forces as the wire size increased. PMID:14560269

Cacciafesta, Vittorio; Sfondrini, Maria Francesca; Ricciardi, Andrea; Scribante, Andrea; Klersy, Catherine; Auricchio, Ferdinando

2003-10-01

137

Evaluation of friction of conventional and metal-insert ceramic brackets in various bracket-archwire combinations.  

Science.gov (United States)

The purpose of the study was to measure and compare the level of frictional resistance generated between conventional ceramic brackets (Transcend Series 6000, 3M Unitek, Monrovia, Calif), ceramic brackets with stainless steel slot (Clarity, 3M Unitek), conventional stainless steel brackets (Victory Series, 3M Unitek), and 3 different orthodontic wire alloys: stainless steel (stainless steel, SDS Ormco, Glendora, Calif), nickel-titanium (Ni-Ti, SDS Ormco), and beta-titanium (TMA, SDS Ormco). All brackets had a 0.022-in slot, and orthodontic wire alloys were tested in 3 different sections: 0.016 in, 0.017 x 0.025 in, and 0.019 x 0.025 in. Each of the 27 bracket-archwire combinations was tested 10 times, and each test was performed with a new bracket-wire sample. Static and kinetic friction were measured on a specially designed apparatus. All data were statistically analyzed (analysis of variance and Scheffé for the bracket effect, Kruskal-Wallis and Mann Whitney for the alloy and section effects). Metal-insert ceramic brackets generated significantly lower frictional forces than did conventional ceramic brackets, but higher values than stainless steel brackets, in agreement with the findings of the few previous reports. Beta-titanium archwires had higher frictional resistances than did stainless steel and nickel-titanium archwires. No significant differences were found between stainless steel and nickel-titanium archwires. All the brackets showed higher static and kinetic frictional forces as the wire size increased. Metal-insert ceramic brackets are not only visually pleasing, but also a valuable alternative to conventional stainless steel brackets in patients with esthetic demands. PMID:14560270

Cacciafesta, Vittorio; Sfondrini, Maria Francesca; Scribante, Andrea; Klersy, Catherine; Auricchio, Ferdinando

2003-10-01

138

DNA Damage in Oral Mucosa Cells of Patients with Fixed Orthodontic Appliances  

Science.gov (United States)

Objective: The release of toxic metal ions from orthodontic alloys has induced concerns regarding the biocompatibility of fixed appliances. This study investigated the genotoxic effect of metal appliances in a sample of patients undergoing fixed orthodontic treatment. Materials and Methods: The study included twenty-five healthy individuals requiring orthodontic therapy in both jaws. The patients were treated by stainless steel orthodontic brackets and nickel-titanium or stainless steel arch wires. The oral mucosa cells were gathered just before the appliance placement and 9 months later. The cells were centrifuged, fixed and dropped onto slides. After staining, the micronucleus (MN) assay was used to determine genome alteration. The data were analyzed by paired sample t-test. Results: The mean micronuclei frequency in the buccal mucosa was 10.6 ± 5.7 per 1000 cells before the appliance placement and 9.2 ± 6.37 per 1000 cells 9 months later. No significant difference was found in the MN count before and 9 months after therapy (p=0.336). Conclusion: Under the conditions used in this study, application of fixed orthodontic appliances did not expose healthy individuals to increased risk of DNA damage in oral mucosa cells. PMID:24910659

Heravi, Farzin; Abbaszadegan, Mohammad Reza; Merati, Mohsen; Hasanzadeh, Nadia; Dadkhah, Ezzat; Ahrari, Farzaneh

2013-01-01

139

Shear bond strength of new and recycled brackets to enamel.  

Science.gov (United States)

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-microm 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-microm aluminum oxide particle air-abrasion was efficient and technically simple, and might provide cost reduction for orthodontists and patients alike. PMID:16721464

Tavares, Stenyo Wanderley; Consani, Simonides; Nouer, Darcy Flávio; Magnani, Maria Beatriz Borges de Araújo; Nouer, Paulo Roberto Aranha; Martins, Laura Moura

2006-01-01

140

[Enamel cracks: influence of orthodontic process].  

Science.gov (United States)

The presence of enamel cracks is not only due to the removal process. It is all the stages before that we need to consider. 1. The presence of risks factors before the treatment (cracks, trauma...) have to be explained to the patient and recorded. 2. The choice of bracket placement: the buccal side is responsible for less cracks than the lingual one. 3. Ceramic brackets need higher debonding forces than metal ones; metal reinforced orthodontic ceramic brackets could be an interesting approach. 4. CVIMR could be better than classic bonds. 5. In case of multiple rebondings, it is better not to etch enamel again but only to level the resin left on tooth surface. 6. Alternatives to removing brackets by pliers are studied, especially for the removal of ceramic brackets to thwart the high debonding force problem : heat, laser... PMID:25158747

Bernard-Granger, Chloé; Gebeile-Chauty, Sarah

2014-09-01

141

Evaluación in vitro de la resistencia friccional entre brackets cerámicos y arcos de acero inoxidable con y sin recubrimiento vítreo aplicado por el método Sol-Gel In vitro evaluation of frictional resistance between ceramic brackets and orthodontic steel wires with and without glass coatings applied by Sol-Gel method  

OpenAIRE

INTRODUCCIÓN: comparar la resistencia friccional estática y dinámica in vitro entre brackets cerámicos y alambres de acero inoxidable con recubrimiento vítreo aplicado por el método Sol-Gel y sin él. MÉTODOS: se prepararon 58 alambres de acero inoxidable AISI 304 de 0.016 x 0.016 con recubrimiento vítreo aplicado por Sol-Gel y sin él. Posteriormente se evaluó la resistencia a la fricción estática y dinámica in vitro de los alambres sobre brackets cerámicos de zafiro monocristal...

Luz Adriana Rendón Arias; Gustavo Adolfo Cano Correa; Alejandro peláez Vargas; Jaramillo Vallejo, Pedro M.; Claudia García Garcia; Yessid Montoya Góez

2008-01-01

142

Adult Orthodontics  

OpenAIRE

Adult orthodontics is becoming a larger proportion of many practices. Adult orthodontics is concerned with striking a balance between achieving optimal proximal and occlusal contact of the teeth, acceptable dentofacial esthetics, normal function, and reasonable stability. With the adult, it is more frequently concerned with physiological adaptation and is often symptom related, whereas with the child the dealing is with the signs. In the past three decades, a major reorientation of orthodonti...

Anita G; Asiya Begum

2010-01-01

143

Adult Orthodontics  

Directory of Open Access Journals (Sweden)

Full Text Available Adult orthodontics is becoming a larger proportion of many practices. Adult orthodontics is concerned with striking a balance between achieving optimal proximal and occlusal contact of the teeth, acceptable dentofacial esthetics, normal function, and reasonable stability. With the adult, it is more frequently concerned with physiological adaptation and is often symptom related, whereas with the child the dealing is with the signs. In the past three decades, a major reorientation of orthodontic thinking has occurred regarding adult patients. Changed lifestyles and patient awareness have increased the demands for adult orthodontic treatment and multidisciplinary dental therapy has allowed better management of the more complicated and unique requirements of the adult patient population, thereby greatly improving the quality of care and treatment prognosis. In addition to goal clarification, adult patients desire treatment efficiency, convenience in appointment timings and good communication with other health care professionals. Almost 80% of the adult patients require interdisciplinary treatment planning and treatment execution. With the adult, consultation with another specialist isn’t occasional. It is the rare adult whom one treats orthodontically without finding it necessary to collaborate with another specialist. This represents both the challenge and the excitement of adult orthodontics.

Anita G

2010-04-01

144

The Orthodontic CYBERJournal  

Science.gov (United States)

The Orthodontic CYBERJournal is a collection of specific case studies, descriptions of procedures and other issues relating to the practice of Orthodontics. While the front page is a bit crowded, the materials within the site are worth all the distractions. A visitor to the site will find journal articles on topics from Thalassemia patients with malocclusion to a simple and effective technique for augmenting molar anchorage. The articles in the CYBERJournal are submitted by professionals in the field and are approved by an esteemed panel which includes practicing and retired orthodontists, professors, and other journal editors. Overall, this site is a valuable tool for anyone interested in the field of orthodontry.

Lifshitz, Abraham

2006-11-09

145

Bonded orthodontic retainers: a review.  

Science.gov (United States)

Recent reports have suggested that long-term retention may be required to prevent posttreatment changes. The bonded orthodontic retainer constructed from composite and multistrand orthodontic wire provides an esthetic and efficient system for maintained retention. The development, indications for use, and clinical techniques are described. The range of materials reported for clinical use in construction of bonded orthodontic retainers are reviewed. Recommmendations based on the literature are made. This review implicates placement of insufficient resin or use of a resin with inadequate abrasion resistance in the failure of bonded fixed retainers. PMID:7625397

Bearn, D R

1995-08-01

146

Lingual Orthodontics  

OpenAIRE

At the early stages of the 80's, most of the practitioners and the patients have been seduced by lingual But the difficulties of the technique have rapidly given a disappointment. Today ten years later the authors present the progress which have been realized: the evolution of the brackets, the accuracy of their placement in the lab procedures, the making of the wire, the increase in patient's comfort. So this article attempts to review some of the advantages, disadvantages, bracket systems a...

Vasu murthy S; Saritha T

2009-01-01

147

Contact allergy problem - danger for doctor and patient during orthodontic treatment. Literature review. Problem alergii kontaktowej - zagro?enie dla lekarza i pacjenta podczas terapii ortodontycznej. Przegl?d pi?miennictwa.  

Directory of Open Access Journals (Sweden)

Full Text Available Allergy has currently become important problem of social life. Development of industry, civilization progress, change of lifestyle lead to increase of hypersensitivities incidents provoked by alimentary, inhaled and contact allergens. This problem especially concerns employees of health service, therefore dentists are highly exposed to the risk. Allergens such as disinfectants, metals, chemical compounds of medical rubber, synthetic materials or aromatic substances are mostly often responsible for occupational diseases developed in doctors. Problem of allergy in dentistry and especially in orthodontics was studied. Polish and foreign medical textbooks and journals containing results of research dealing with nickel, acrylate and latex allergy. Authoresses also searched medical bases: EBSCO and PUBMED, typing following keywords: nickel in orthodontics, contact allergy in orthodontics, acrylate in orthodontics and dentistry, latex in orthodontic treatment and in dentistry. A literature review and searching of internet bases did not interchangeably prove influence of orthodontic treatment on development of allergy to nickel. The studies find evidence of either intensification of allergy symptoms as well as of decrease of skin hypersensitivity in patients with nickel contact found in the past. Frequent application of latex and acrylates materials can cause allergy in medical staff and their patients. Since number of allergy-incidents increase, detailed anamnesis enabling early diagnosis of this problem should become basic procedure in dental or orthodontic offices. If potential hypersensitivity is revealed, sensitizing materials should be eliminated and replaced with non sensitizing ones. Therefore, nickel free orthodontic brackets and archwires, as well as latex free elastics may be promising solution conquering allergy-occurrence. Problem of allergy in dentistry and especially in orthodontics was widely discussed basing on Polish and foreign literature. Allergy against latex, nickel and acrylates were discussed in details. Furthermore, issue of hypersensitivity in medical stuff and patients was also highlighted.

Agnieszka Sieja

2010-03-01

148

Using Little's Irregularity Index in orthodontics: outdated and inaccurate?  

LENUS (Irish Health Repository)

Little\\'s Irregularity Index (LII) was devised to objectively score mandibular incisor alignment for epidemiological studies but has been extended to assess the relative performance of orthodontic brackets, retainer or treatment modalities. Our aim was to examine the repeatability and precision of LII measurements of four independent examiners on the maxillary arch of orthodontic patients. The hypothesis was that the reproducibility of individual contact point displacement measurements, used to calculate the LII score, are inappropriate.

Macauley, Donal

2012-12-01

149

A study in vitro on radiation effects by Er:YAG laser combined with the fluorine therapy in the acid resistance of the dental enamel submitted to orthodontical brackets; Um estudo in vitro sobre os efeitos da irradiacao pelo laser de Er:YAG combinado com a terapia com fluor na resistencia acida do esmalte de dentes submetidos a aparelho ortodontico fixo  

Energy Technology Data Exchange (ETDEWEB)

Several researches have been demonstrating an increase in the resistance acid of the enamel surface when irradiated by some lasers types as Nd:YAG, C0{sub 2}, Er:YAG, and others, mainly when combined with the fluoride therapy after the irradiation of the laser. This study in vitro used the laser of Er:YAG which density of energy of 8.1 J/cm{sup 2} on the enamel about of orthodontical brackets of teeth extracted pre-molars. These teeth were then submitted to a rich way in S. mutans for twenty one days. The cases were analyzed: (1) enamel surface without any treatment, (2) enamel surface without any irradiation laser, but with therapy with acidulated phosphate fluoride, (3) enamel surface irradiated with laser of Er:YAG and (4) enamel surface irradiated by laser of Er:YAG and with application of acidulated phosphate fluoride. The results were analyzed through optical microscopy and scanning electron microscopy. The morphologic changes observed to the scanning electron microscopy suggest increase in the acid resistance of the enamel surface. However, to the optical microscopy, it was still possible to visualize undesirable white stains in the surface of the enamel. (author)

Yoshiyasu, Roseli Y.A

2001-07-01

150

Orthodontics and dentistry for the hemophilic patient.  

Science.gov (United States)

In this presentation we have contrasted the normal blood-clotting mechanism with the failure to form blood clots in hemophiliacs due to the absence of protein factors necessary for conversion of prothrombin to thrombin. The statistics, hereditary basis, and long-term disabling consequences of hemophilia to the severely ffected patient are described. The systemic means of minimizing severe joint disabilities and serious internal bleeding hazards by employing concentrates of antihemophilic factors to reverse the bleeding defects are discussed. Availability and advantages of the types of concentrates are explained. The fatalistic attitude of hemophiliacs toward hepatitis is discussed, along with admonitions to avoid the use of aspirin, alcohol, and buttock injections. Alternative medications for pain are recommended; and injection sites for pediatric patients are suggested. The details of simplified oral surgical management of hemophilic patients without hospitalization are described, including local anesthetic injection technique, method of performing extractions, general anesthesia techniques when indicated, materials for packing of extraction sockets, regimen and precautions in use of Amicar administration for clot maintenance, postoperative diet, and postsurgical activity guidelines. Also noted is the self-administration of intravenous concentrate infusions at home in the event of hemorrhagin, so that bleeding is on the way to bein controlled even before the patient reaches the hospital. We avoided orthodontic treatment of hemophilic patients in the past; however, recently developed bracket-fixation techniques and auxiliary aids; along with an enlightened understanding that gingival bleeding is ot to be feared, have changed our attitude, and we now treat hemophilic patients in much the same manner as otherwise normal orthodontic patients... PMID:1101695

Grossman, R C

1975-10-01

151

Shear bond strength of metallic and ceramic brackets using color change adhesives  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: determinar a resistência adesiva à tração de braquetes ortodônticos usando resinas coloridas que se propõem a ajudar na remoção do excesso de material adesivo e compará-las com um adesivo tradicional. MÉTODOS: Noventa braquetes metálicos e 90 cerâmicos foram colados com dois adesivos color [...] idos e com um adesivo tradicional em incisivos inferiores bovinos, sendo aplicada tração com uma máquina de ensaios universal. Após a descolagem, os dentes foram observados em microscópio para a determinação do índice de adesivo remanescente (ARI). RESULTADOS: a análise estatística (testes ANOVA, de Tukey e de Kruskall-Wallis) demonstrou que a força de união média foi significativa entre os adesivos usados. Os ARIs mais comuns foram aqueles onde o adesivo permaneceu no esmalte. CONCLUSÃO: a resistência adesiva foi similar entre braquetes metálicos e cerâmicos quando o mesmo adesivo foi usado. Os resultados do ARI demonstraram que esses adesivos são seguros, mesmo com o uso de braquetes cerâmicos. A resistência adesiva foi muito baixa para Ortodontia no grupo colado com Ortho Lite Cure. Abstract in english OBJECTIVE: To determine the shear bond strength of orthodontic brackets using color change adhesives that are supposed to aid in removing excess of bonding material and compare them to a traditional adhesive. METHODS: Ninety metallic and ninety ceramic brackets were bonded to bovine incisors using t [...] wo color change adhesives and a regular one. A tensile stress was applied by a universal testing machine. The teeth were observed in a microscope after debonding in order to determine the Adhesive Remnant Index (ARI). RESULTS: The statistical analysis (ANOVA, Tukey, and Kruskall-Wallis tests) demonstrated that the mean bond strength presented no difference when metallic and ceramic brackets were compared but the bond resistance values were significantly different for the three adhesives used. The most common ARI outcome was the entire adhesive remaining on the enamel. CONCLUSIONS: The bond strength was similar for metallic and ceramic brackets when the same adhesive system was used. ARI scores demonstrated that bonding with these adhesives is safe even when ceramic brackets were used. On the other hand, bond strength was too low for orthodontic purposes when Ortho Lite Cure was used.

Aisha de Souza Gomes, Stumpf; Carlos, Bergmann; José Renato, Prietsch; Juliane, Vicenzi.

2013-04-01

152

Nd:YAG Laser-aided ceramic brackets debonding: Effects on shear bond strength and enamel surface  

Energy Technology Data Exchange (ETDEWEB)

In order to evaluate the efficiency of Nd:YAG laser-aided ceramic brackets debonding technique, both ceramic brackets and metallic brackets were bonded with orthodontic adhesive to 30 freshly extracted premolars. The specimens were divided into three groups, 10 in each, according to the brackets employed and the debonding techniques used: (1) metallic brackets with shear debonding force, (2) ceramic brackets with shear debonding force, and (3) ceramic brackets with Nd:YAG laser irradiation. The result showed that laser irradiation could diminish shear bond strength (SBS) significantly and produce the most desired ARI scores. Moreover, scanning electron microscopy investigation displayed that laser-aided technique induced little enamel scratch or loss. It was concluded that Nd:YAG laser could facilitate the debonding of ceramic brackets and diminish the amount of remnant adhesive without damaging enamel structure.

Han Xianglong [State Key Laboratory of Oral Diseases, Sichuan University, Chengdu 610041 (China); Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Liu Xiaolin [Department of Orthodontics, Stomatology Hospital, Dalian University, Dalian 116021 (China); Bai Ding [State Key Laboratory of Oral Diseases, Sichuan University, Chengdu 610041 (China); Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China)], E-mail: baiding88@hotmail.com; Meng Yao; Huang Lan [Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China)

2008-11-15

153

Nd:YAG Laser-aided ceramic brackets debonding: Effects on shear bond strength and enamel surface  

International Nuclear Information System (INIS)

In order to evaluate the efficiency of Nd:YAG laser-aided ceramic brackets debonding technique, both ceramic brackets and metallic brackets were bonded with orthodontic adhesive to 30 freshly extracted premolars. The specimens were divided into three groups, 10 in each, according to the brackets employed and the debonding techniques used: (1) metallic brackets with shear debonding force, (2) ceramic brackets with shear debonding force, and (3) ceramic brackets with Nd:YAG laser irradiation. The result showed that laser irradiation could diminish shear bond strength (SBS) significantly and produce the most desired ARI scores. Moreover, scanning electron microscopy investigation displayed that laser-aided technique induced little enamel scratch or loss. It was concluded that Nd:YAG laser could facilitate the debonding of ceramic brackets and diminish the amount of remnant adhesive without damaging enamel structure

154

Bracket for photovoltaic modules  

Science.gov (United States)

Brackets for photovoltaic ("PV") modules are described. In one embodiment, a saddle bracket has a mounting surface to support one or more PV modules over a tube, a gusset coupled to the mounting surface, and a mounting feature coupled to the gusset to couple to the tube. The gusset can have a first leg and a second leg extending at an angle relative to the mounting surface. Saddle brackets can be coupled to a torque tube at predetermined locations. PV modules can be coupled to the saddle brackets. The mounting feature can be coupled to the first gusset and configured to stand the one or more PV modules off the tube.

Ciasulli, John; Jones, Jason

2014-06-24

155

Allergy and orthodontics  

OpenAIRE

The aim of this paper is to review the current literature on allergy in orthodontics and to identify the predisposing factors and the implications of the allergic reaction in the management of patients during orthodontic treatment. A computerized literature search was conducted in PubMed for articles published on allergy in relation to orthodontics. The MeSH term used was allergy and orthodontics. Allergic response to alloys in orthodontics, particularly nickel, has been extensively studied a...

Chakravarthi, Sunitha; Padmanabhan, Sridevi; Chitharanjan, Arun B.

2012-01-01

156

Model and Analysis on Car Seat Mounting Bracket  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract--In this paper, we are desiged a car seat mounting bracket with seat arrangement by using Pro/E Softwarefor Automobile Applications. We have Conducted, structural analysis by varying the seat bracket material. By extracting the results Comparison is done for three materials to validate better material for car seat mounting bracket to find out which material is best for the withstand in loading condition. Analysis is by using ANSYS software.

M.V.Srinivasan#1 , M. Lava Kumar

2013-08-01

157

Morphological characterization of as-received and in vivo orthodontic stainless steel archwires.  

Science.gov (United States)

This study was undertaken to evaluate the material degradation of clinical bracket-archwire-contacting surfaces after in vivo orthodontic use. Twenty-four stainless steel multiloop edgewise archwires with two different cross sections (0.016 x 0.016 and 0.016 x 0.022 inches) were used for at least 6 months in the mouths of 14 patients. The surfaces of both as-received (cross-section of 0.016 x 0.016, 0.016 x 0.022, and 0.017 x 0.025 inches) and the in vivo wires were examined using scanning electron microscopy. The as-received wires exhibited an inhomogeneous surface with different surface irregularities resulting from the manufacturing process. For the in vivo archwires, an increase in the variety, type, and number of surface irregularities were observed. Crevice corrosion occurred not only at surface irregularities formed during manufacturing and orthodontic handling but also at the bracket-archwire-contacting surfaces and at the archwire surfaces coated with plaque and food remnants. This corrosion may be linked to the formation of a micro-environment at these locations. In addition, a limited number of signs of degradation induced during in vivo testing due to wear and friction were observed. PMID:19188281

Daems, Julie; Celis, Jean-Pierre; Willems, Guy

2009-06-01

158

Comparison of the debonding characteristics of two innovative ceramic bracket designs.  

Science.gov (United States)

Two new ceramic brackets-one designed with a metal-lined arch wire slot and the other with an epoxy resin base-have been recently introduced. The new brackets are thought to combine the esthetic advantages of ceramics and the functional advantages of debonding metal brackets. The purpose of this study was to compare the following: 1) the shear bond strength of the 2 brackets, and 2) the bond failure location when the brackets are debonded with pliers. Sixty-one Clarity (3M Unitek) collapsible ceramic brackets and 66 MXi (TP Orthodontics, Inc) brackets were bonded to the teeth with the same bonding system. The Zwick Universal Test Machine (Zwick Gm bH & Co) was used to determine the shear bond strength force levels needed to debond the brackets. The appropriate pliers also were used to debond both types of brackets to determine the mode of bond failure that will be encountered clinically. After debonding, all the teeth and brackets were examined with 10x magnification. Any adhesive that remained after the bracket removal was assessed according to the Adhesive Remnant Index. The findings indicated that the shear bond strength of the Clarity ceramic brackets was significantly greater than that of the MXi ceramic brackets. However, both brackets exhibited forces that were adequate for clinical use. The Adhesive Remnant Index scores for both the shear test and the plier debonding indicated a similar bond failure pattern when the 2 ceramic brackets were compared with each other. This suggests that, when these brackets are debonded with the Weingart (Ormco) and ETM (Ormco) pliers, there was a greater tendency for most of the adhesive to remain on the enamel surface. In conclusion, the most efficient method to debond the MXi ceramic bracket is by placing the blades of the ETM 346 pliers between the bracket base and the enamel surface. On the other hand, the most efficient method of debonding the Clarity bracket is by using the Weingart pliers and applying pressure to the tiewings. When the 2 ceramic brackets were debonded as recommended here, most of the residual adhesive remained on the enamel surface, a pattern similar to the one observed previously with metal brackets. The failure at the bracket-adhesive interface decreases the probability of enamel damage but necessitates the removal of more residual adhesive after debonding. PMID:10393585

Bishara, S E; Olsen, M E; VonWald, L; Jakobsen, J R

1999-07-01

159

In vivo bracket bond strength using two adhesive systems applied under wet and dry conditions.  

Science.gov (United States)

The purpose of this study was to investigate, in vivo, the bond strength of two adhesive materials: a moisture insensitive primer (MIP)* and a one step self etching primer (SEP)*, both used with Transbond XT* on dry and wet enamel and an adhesion time of 10-15 minutes. First or second upper and/or lower bicuspids (n = 124), to be extracted for orthodontic reasons, were used. A comparison of the materials' behavior was conducted under four different situations: 1) MIP on enamel etched and dry; 2) MIP on a surface etched and wetted with patient's saliva; 3) SEP on a dry field, 4) SEP on a saliva-wet enamel. For statistical analysis, Dunn-Sidak's multiple comparison test was applied with a probability of less than 0.05 (before correction). Stainless steel brackets with mesh-backed pads were bonded to the teeth. Bond strength was tested with modified orthodontic pliers on which a strain-gage was fixed to measure handle deformation while debonding. Moisture insensitive primer tested on wet enamel showed the highest mean bond strength outcomes (8.98 MPa) compared to one step etching primer (5.81 MPa). Statistical difference between these groups was significant (p = 0.000). Standard deviation was lower for the one-step technique, under dry and wet conditions. Since the media bond strength of SEP proved sufficient for clinical purposes and its behavior tended to be more homogeneous, this was considered the best choice. PMID:17121197

Ciola, Elida N; Picco, Alicia M; Sois, Ana M; Lucena, Mercedes H; Alonso, Verónica; Valvo, Maela; García, Luis; Geazzi, Ariel

2006-01-01

160

Development and evaluation of a reinforced polymeric biomaterial for use as an orthodontic wire  

Science.gov (United States)

Composite archwires have the potential to provide esthetic and functional improvements over conventional wires. As part of an ongoing effort to bring these materials into general use, composite wires were fabricated using a photo-pultrusion manufacturing technique, and subsequently coated with a 10 mum layer of poly(chloro-p-xylylene). Coated and uncoated composites were subjected to several different evaluations to assess their ability to perform the functions of an orthodontic archwire. An investigation of the viscoelastic behavior of uncoated composite wires was conducted at a physiological temperature of 37°C using a bend stress relaxation test. Over 90 day testing periods, energy losses increased with decreasing reinforcement levels from to 8% of the initial wire stress. Final viscous losses were 1% for all reinforcement levels. Relaxed elastic moduli for the composite wires were comparable to the reported elastic moduli of conventional orthodontic wires that are typically used for initial and intermediate alignment procedures. Frictional characteristics were evaluated in passive and active configurations for uncoated composite wires against three contemporary orthodontic brackets. Kinetic coefficients of friction were the same for all wire-bracket combinations tested and were slightly lower than the reported coefficients of other initial and intermediate alignment wires. Wear patterns on the wires, which were largely caused by sharp leading edges of the bracket slots, were characteristic of plowing and cutting wear behaviors. This wear caused glass fibers to be released from the surface of the wires, presenting a potential irritant. Coated composite wires were subjected to the same frictional analysis as the uncoated wires. A mathematical model of the archwire-bracket system was derived using engineering mechanics, and used to define a coefficient of binding. The coating increased the frictional coefficients of the wires by 72%, yet the binding coefficient was unchanged. When frictional data for initial and intermediate alignment wires were compared, the coated composites had higher friction than all but one couple. However, binding coefficients were comparable. Glass fibers were contained for all testing conditions, although the coating was often damaged by plowing or cutting wear. Overall, the coating improved the clinical acceptability of the composite wires.

Zufall, Scott William

161

Quantitative analysis of S. mutans and S. sobrinus cultivated independently and adhered to polished orthodontic composite resins  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english In Orthodontics, fixed appliances placed in the oral cavity are colonized by microorganisms. OBJECTIVE: The purpose of this study was to quantitatively determine the independent bacterial colonization of S. mutans and S. sobrinus in orthodontic composite resins. MATERIAL AND METHODS: Seven orthodont [...] ic composite adhesives for bonding brackets were selected and classified into 14 groups; (GIm, GIs) Enlight, (GIIm, GIIs) Grengloo, (GIIIm, GIIIs) Kurasper F, (GIVm, GIVs) BeautyOrtho Bond, (GVm, GVs) Transbond CC, (GVIm, GVIs) Turbo Bond II, (GVIIm, GVIIs) Blugloo. 60 blocks of 4x4x1 mm of each orthodontic composite resin were made (total 420 blocks), and gently polished with sand-paper and ultrasonically cleaned. S. mutans and S. sobrinus were independently cultivated. For the quantitative analysis, a radioactive marker was used to codify the bacteria (³H) adhered to the surface of the materials. The blocks were submerged in a solution with microorganisms previously radiolabeled and separated (210 blocks for S. mutans and 210 blocks for S. sobrinus) for 2 hours at 37ºC. Next, the blocks were placed in a combustion system, to capture the residues and measure the radiation. The statistical analysis was calculated with the ANOVA test (Sheffè post-hoc). RESULTS: Significant differences of bacterial adhesion were found amongst the groups. In the GIm and GIs the significant lowest scores for both microorganisms were shown; in contrast, the values of GVII for both bacteria were significantly the highest. CONCLUSIONS: This study showed that the orthodontic composite resin evaluated in the GIm and GIs, obtained the lowest adherence of S. mutans and S. sobrinus, which may reduce the enamel demineralization and the risk of white spot lesion formation.

Ulises, Velazquez-Enriquez; Rogelio Jose, Scougall-Vilchis; Rosalia, Contreras-Bulnes; Jaime, Flores-Estrada; Shinsuke, Uematsu; Ryozo, Yamaguchi.

2012-10-01

162

Quantitative analysis of S. mutans and S. sobrinus cultivated independently and adhered to polished orthodontic composite resins  

Directory of Open Access Journals (Sweden)

Full Text Available In Orthodontics, fixed appliances placed in the oral cavity are colonized by microorganisms. OBJECTIVE: The purpose of this study was to quantitatively determine the independent bacterial colonization of S. mutans and S. sobrinus in orthodontic composite resins. MATERIAL AND METHODS: Seven orthodontic composite adhesives for bonding brackets were selected and classified into 14 groups; (GIm, GIs Enlight, (GIIm, GIIs Grengloo, (GIIIm, GIIIs Kurasper F, (GIVm, GIVs BeautyOrtho Bond, (GVm, GVs Transbond CC, (GVIm, GVIs Turbo Bond II, (GVIIm, GVIIs Blugloo. 60 blocks of 4x4x1 mm of each orthodontic composite resin were made (total 420 blocks, and gently polished with sand-paper and ultrasonically cleaned. S. mutans and S. sobrinus were independently cultivated. For the quantitative analysis, a radioactive marker was used to codify the bacteria (³H adhered to the surface of the materials. The blocks were submerged in a solution with microorganisms previously radiolabeled and separated (210 blocks for S. mutans and 210 blocks for S. sobrinus for 2 hours at 37ºC. Next, the blocks were placed in a combustion system, to capture the residues and measure the radiation. The statistical analysis was calculated with the ANOVA test (Sheffè post-hoc. RESULTS: Significant differences of bacterial adhesion were found amongst the groups. In the GIm and GIs the significant lowest scores for both microorganisms were shown; in contrast, the values of GVII for both bacteria were significantly the highest. CONCLUSIONS: This study showed that the orthodontic composite resin evaluated in the GIm and GIs, obtained the lowest adherence of S. mutans and S. sobrinus, which may reduce the enamel demineralization and the risk of white spot lesion formation.

Ulises Velazquez-Enriquez

2012-10-01

163

Impact resistance of ceramic brackets according to ophthalmic lenses standards.  

Science.gov (United States)

The overall resistance to accidental blows of the many ceramic brackets that are sold today has not been explored. Facing a similar diversity, the eyeglasses industry has chosen to standardize the testing of lenses by subjecting them to the drop of a steel ball. By slightly modifying this test, 10 brands of ceramic brackets were examined. In most cases, the findings coincided with those found by other authors when duplicating debonding. Thus, polycrystalline ceramics with bulkier structures and glazed surfaces were found to be more resistant to impact than the monocrystalline brackets, the loftier real "twins," and the less dense attachments. Protruding tie wings and bases were liabilities, and domed configurations seemed to deflect the blows. Bulkier "single" designs alone did not offer a guarantee of impact resistance when not accompanied by an appropriate microstructure and a smooth surface. The ceramic brackets most resistant to impact were found to be 20/20 by American Orthodontics and Fascination by Dentaurum. Medium resistance was displayed by Lumina by Ormco, Allure III and Allure by GAC, Transcend 2000 and Transcend by Unitek/3M; the last was not as good as the other four. The least resistant were Illusion by Ortho-Organizers, Intrigue by Lancer Orthodontics, and Starfire TMB by "A"-Co. Probably because of its real twin design, the last bracket lends itself to the highest probability for accidental breakage. Although resistance to impact and accidental debonding is desirable from the point of view of treatment, the advantage should be weighted against the chance of enamel fracture. Indeed a weak bracket attached with a soft adhesive may be preferable when the chance of an increased exposure to accidental blows is probable. In such cases, the ceramic may take the brunt of the force, instead of the tooth. PMID:9971927

Matasa, C G

1999-02-01

164

Effect of calcium hydroxide-based materials on periapical tissue healing and orthodontic root resorption of endodontically treated teeth in dogs.  

Science.gov (United States)

This study evaluated periapical tissue healing and orthodontic root resorption of endodontically treated teeth sealed with calcium hydroxide in dogs. The sample consisted of three contralateral pairs of maxillary incisors and two contralateral pairs of mandibular incisors in each of two dogs using a split mouth design. After biomechanical preparation of the teeth in the first group (n = 10), a Ca(OH)(2) dressing was placed for 14 days before root canal filling with Ca(OH)(2)-based sealer (Sealapex) and gutta-percha points. In the second group (n = 10), root canals were obturated immediately after the mechanical preparation with gutta-percha points and zinc oxide and eugenol (ZOE)-based sealer (Endofill). After completion of endodontic treatment, the teeth were moved with an orthodontic appliance with a calibrated force of 200 g, reactivated every 21 days. After 105 days, the animals were killed and the teeth were removed upon completion of active treatment, without a period of recovery, and prepared for histomorphological analysis. All sections of each tooth were graded subjectively on a scale from one to four to obtain the average of the 16 histomorphological parameters analysed. Evaluation of the differences between the two treatment protocols was made with Mann-Whitney U-test. It was observed that the teeth treated with Ca(OH)(2)-based materials provided better outcomes (P = 5%), with complete repair of all root resorption areas, high rate of biological closure of the main canal and apical accessory canals by newly formed cementum, less intense and extensive chronic inflammatory infiltrate, and better organization of the periodontal ligament. Under the tested conditions, Ca(OH)(2)-based materials had a favourable action on periapical tissue healing and repair of orthodontic root resorption in endodontically treated dogs' teeth. PMID:19290903

de Souza, Ricardo Sampaio; de Souza, Valdir; Holland, Roberto; Gomes-Filho, João Eduardo; Murata, Sueli Satomi; Sonoda, Celso Koogi

2009-04-01

165

Face Adaptation in Orthodontics  

OpenAIRE

Bilateral Controversy in orthodontic science is widely present in different patterns; one of the most common is the debate between early versus late orthodontic treatment. This paper is going to demonstrate two clinical cases of class III malocclusion which are treated orthodontically, one in early mixed dentition and the other in permanent dentition. The face is highly capable to adapt to the changes achieved by orthodontics provided the earlier treatment begins, the more the face adapts to ...

Maen Mahfouz

2014-01-01

166

Cellulose Nanofibre Mesh for Use in Dental Materials  

OpenAIRE

The aim of this study was to produce a 3D mesh of defect free electrospun cellulose acetate nanofibres and to use this to produce a prototype composite resin containing nanofibre fillers. This might find use as an aesthetic orthodontic bracket material or composite veneer for restorative dentistry. In this laboratory based study cellulose acetate was dissolved in an acetone and dimethylacetamide solvent solution and electrospun. The spinning parameters were optimised and lithium chloride adde...

Ireland, Anthony J.; Boyd, Stephen A.; Bo Su; Sandy, Jonathan R.

2012-01-01

167

Influence of in vitro pigmenting of esthetic orthodontic ligatures on smile attractiveness  

OpenAIRE

OBJECTIVE: To evaluate the perception of dental students and orthodontists on the degree of influence that pigmented esthetic elastic ligatures have on smile attractiveness, by judging clinical photographs. METHODS: Sixteen clinical facial photographs of the smile and 16 close up images of the smile of a single patient wearing monocrystalline porcelain orthodontic brackets, Teflon coated NiTi wire brackets and esthetic elastic ligatures of five different commercial brands were distributed int...

Camila Ferraz; Marcelo de Castellucci; Márcio Sobral

2012-01-01

168

Dental Health and Orthodontic Problems  

Science.gov (United States)

... Orthodontic Problems Healthy Living Listen Dental Health and Orthodontic Problems Article Body Dental Health Twin studies conducted ... color can be tinted to match the teeth. Orthodontic Problems Crooked teeth, overbites and underbites are best ...

169

Exploring the publications in three major orthodontic journals  

OpenAIRE

Objective: To analyze the types of articles and authorship characteristics of three orthodontic journals-American Journal of Orthodontics and Dentofacial Orthopedics (AJODO), The Angle Orthodontist (AO), and European Journal of Orthodontics (EJO)-published between 2008 and 2012 and to assess the differences in content within this period and an earlier period of 1998 to 2002. Materials and Methods: Each journal's content was accessed through the web edition. From each article, the following pa...

Baumgartner, Stefan; Pandis, Nikolaos; Eliades, Theodore

2014-01-01

170

Impact of brackets on smile esthetics: laypersons and orthodontists perception  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: esse estudo analisou a influência dos aparelhos ortodônticos na estética do sorriso em avaliação por adolescentes, adultos e ortodontistas. MÉTODOS: foram utilizadas fotografias faciais do sorriso de uma jovem mulher, usando-se as seguintes combinações: aparelho ortodôntico de metal com li [...] gaduras de diferentes cores (verde, vermelho e cinza); aparelho ortodôntico cerâmico (ligadura transparente); e sem aparelho - resultando em cinco fotografias de 15x20cm. Para a avaliação das fotografias, 16 adolescentes leigos, 16 adultos leigos e 16 ortodontistas foram selecionados de forma randômica. As fotografias foram aleatoriamente organizadas em um álbum, acompanhadas de uma escala visual analógica (EVA) para o registro das notas. As notas das duas avaliações de cada grupo (adolescentes, adultos e ortodontistas) foram submetidas à análise de erro (teste pareado de Wilcoxon) e comparação múltipla de grupos pelo teste de Kruskal-Wallis com significância de 5%. RESULTADOS: ortodontistas, adultos e adolescentes concordaram em suas opiniões, porém, os ortodontistas deram notas menores em suas avaliações. Pôde ser observado que os braquetes cerâmicos foram mais aceitos, considerando-se a estética do sorriso, uma vez que os braquetes metálicos tiveram as menores notas. CONCLUSÃO: ortodontistas, adultos e adolescentes parecem preferir soluções estéticas durante o tratamento ortodôntico. Abstract in english OBJECTIVE: This study evaluated the influence of orthodontic appliances on smile esthetics assessed by lay adolescents, lay adults and orthodontists. METHODS: A facial photograph of a smiling young woman was used under the following conditions: With metal orthodontic brackets ligated by different el [...] astic ligature colors (green, red and gray), with ceramic bracket brackets (transparent elastic ligature) and without brackets, totaling five 15 x 20 cm pictures. For the photograph assessment, 16 lay adolescents, 16 lay adults and 16 orthodontists were randomly selected. The photographs were randomly arranged in an album, followed by a visual analog scale (VAS) for the scores registration. Scores in both evaluations of each group of evaluators (adolescents, adults and orthodontists) were submitted to error analysis by WILCOXON test and multiple comparison among groups performed by Kruskal - Wallis at 5% significance. RESULTS: Orthodontists, adults and adolescents agreed in their opinions, although the orthodontists gave lower scores in their assessments. It could be observed that ceramic brackets were more acceptable concerning the smile esthetics, whereas the metal brackets received the lowest scores. CONCLUSION: Orthodontists, adults and even adolescents seem to prefer esthetic solutions during orthodontic treatment.

Seandra Cordeiro de, Oliveira; Rachel D' Aurea, Furquim; Adilson Luiz, Ramos.

2012-10-01

171

Laser Application in Prevention of Demineralization in Orthodontic Treatment  

OpenAIRE

One common negative side effect of orthodontic treatment with fixed appliances is the development of incipient caries lesions around brackets, particularly in patients with poor oral hygiene. Different methods have been used to prevent demineralization such as fluoride therapy and application of sealant to prevent caries. The recent effort to improve the resistance against the demineralization is by the application of different types of lasers. The purpose of this review article is discuss...

Hooman Sadr Haghighi; Mahsa Skandarinejad; Amir Ardalan Abdollahi

2013-01-01

172

Fractional Poisson Bracket  

OpenAIRE

In the present paper fractional Hamilton-Jacobi equation has been derived for dynamical systems involving Caputo derivative. Fractional Poisson-bracket is introduced. Further Hamilton's canonical equations are formulated and quantum wave equation corresponds to the fractional Hamilton-Jacobi equation is suggested. Illustrative examples have been worked out to explain the formalism.

Golmankhaneh, Alireza Khalili

2008-01-01

173

Quantizing Dirac and Nambu Brackets  

OpenAIRE

We relate classical and quantum Dirac and Nambu brackets. At the classical level, we use the relations between the two brackets to gain some insight into the Jacobi identity for Dirac brackets, among other things. At the quantum level, we suggest that the Nambu bracket is the preferred method for introducing constraints, although at the expense of some unorthodox behavior, which we describe in detail.

Curtright, Thomas; Zachos, Cosmas

2003-01-01

174

Face Adaptation in Orthodontics  

Directory of Open Access Journals (Sweden)

Full Text Available Bilateral Controversy in orthodontic science is widely present in different patterns; one of the most common is the debate between early versus late orthodontic treatment. This paper is going to demonstrate two clinical cases of class III malocclusion which are treated orthodontically, one in early mixed dentition and the other in permanent dentition. The face is highly capable to adapt to the changes achieved by orthodontics provided the earlier treatment begins, the more the face adapts to our standards; the later treatment begins, the more our standards have to adapt to the face.

Maen Mahfouz

2014-07-01

175

Allergy and orthodontics.  

Science.gov (United States)

The aim of this paper is to review the current literature on allergy in orthodontics and to identify the predisposing factors and the implications of the allergic reaction in the management of patients during orthodontic treatment. A computerized literature search was conducted in PubMed for articles published on allergy in relation to orthodontics. The MeSH term used was allergy and orthodontics. Allergic response to alloys in orthodontics, particularly nickel, has been extensively studied and several case reports of nickel-induced contact dermatitis have been documented. Current evidence suggests that the most common allergic reaction reported in orthodontics is related to nickel in orthodontic appliances and allergic response is more common in women due to a previous sensitizing exposure from nickel in jewellery. Studies have implicated allergy in the etiology of hypo-dontia. It has also been considered as a high-risk factor for development of extensive root resorption during the course of orthodontic treatment. This review discusses the relationship and implications of allergy in orthodontics. PMID:24987632

Chakravarthi, Sunitha; Padmanabhan, Sridevi; Chitharanjan, Arun B

2012-10-01

176

Finite element modeling of superelastic nickel-titanium orthodontic wires.  

Science.gov (United States)

Thanks to its good corrosion resistance and biocompatibility, superelastic Ni-Ti wire alloys have been successfully used in orthodontic treatment. Therefore, it is important to quantify and evaluate the level of orthodontic force applied to the bracket and teeth in order to achieve tooth movement. In this study, three dimensional finite element models with a Gibbs-potential-based-formulation and thermodynamic principles were used. The aim was to evaluate the influence of possible intraoral temperature differences on the forces exerted by NiTi orthodontic arch wires with different cross sectional shapes and sizes. The prediction made by this phenomenological model, for superelastic tensile and bending tests, shows good agreement with the experimental data. A bending test is simulated to study the force variation of an orthodontic NiTi arch wire when it loaded up to the deflection of 3mm, for this task one half of the arch wire and the 3 adjacent brackets were modeled. The results showed that the stress required for the martensite transformation increases with the increase of cross-sectional dimensions and temperature. Associated with this increase in stress, the plateau of this transformation becomes steeper. In addition, the area of the mechanical hysteresis, measured as the difference between the forces of the upper and lower plateau, increases. PMID:25458153

Naceur, Ines Ben; Charfi, Amin; Bouraoui, Tarak; Elleuch, Khaled

2014-10-16

177

Effect of Activation Mode on Shear Bond Strength of Metallic Brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo deste estudo foi avaliar a resistência de união ao cisalhamento (RUC) de braquetes ortodônticos metálicos colados ao dente bovino utilizando resinas compostas ativadas por luz ou quimicamente ativadas. Cento e vinte incisivos mandibulares bovinos foram divididos em 6 grupos (n=20), de aco [...] rdo com o material de colagem: Transbond XT (T); Enforce Dual (ED); Enforce químico (EC); Enforce ativado por luz (EL); Concise Ortodontico (C); e RelyX Unicem Capsula (UN). Braquetes metálicos foram posicionados e firmemente colados aos dentes. A ativação por luz para os grupos T, ED, EL e UN foi realizada em quatro exposições, sendo uma em cada lado do braquete, para um tempo total de exposição de 20 s usando o aparelho XL2500 (3M ESPE). Os grupos EC e C foram ativados quimicamente. Após, todas as amostras foram armazenadas em água deionizada a 37 °C por 24 h. O teste de resistência de união ao cisalhamento foi realizado após o período de armazenagem, à velocidade de 1 mm/minuto. Os dados foram submetidos à Análise de Variância e ao teste de Tukey (?=0,05). O índice de remanescente adesivo (IRA) foi avaliado em aumento de 8x. O valor de RUC (MPa) do grupo C (17,72±4,45) foi significantemente maior do que o de outros grupos (p Abstract in english The aim of this study was to evaluate the shear bond strength (SBS) of metallic orthodontic brackets bonded to bovine teeth using light-activated or chemically activated composite resins. One hundred and twenty bovine mandibular incisors were divided into 6 groups (n=20), according to the bonding ma [...] terials: Transbond XT (T); Enforce Dual (ED); Enforce chemical (EC); Enforce Light-activated (EL); Concise Orthodontic (C); and RelyX Unicem Capsule (UN). Metallic brackets were positioned and firmly bonded to the teeth. Light-activation for T, ED, EL and UN was carried out with four exposures on each side of the bracket with 20 s total exposure times using XL2500 (3M ESPE). EC and C were chemically cured. Next, all specimens were stored in deionized water at 37 °C for 24 h. The shear bond strength was carried out at a crosshead speed of 1.0 mm/min. Data were subjected to one-way ANOVA and Tukey's test (?=0.05). The adhesive remnant index (ARI) was evaluated at 8× magnification. C (17.72±4.45) presented significantly higher SBS means (in MPa) than the other groups (p

Americo Bortolazzo, Correr; Ana Rosa, Costa; Adriana Simoni, Lucato; Silvia Amelia, Vedovello; Heloisa Cristina, Valdrighi; Mario, Vedovello Filho; Lourenco, Correr-Sobrinho.

2013-09-01

178

Halogen light versus LED for bracket bonding: shear bond strength  

Directory of Open Access Journals (Sweden)

Full Text Available INTRODUCTION: LED light-curing devices seek to provide a cold light activator which allows protocols of material polymerization with shorter duration. OBJECTIVE: The present study aimed to evaluate the shear bond strength of bracket bonding using three types of light-curing devices: One with halogen light (Optilight Plus - Gnatus and two with LEDs (Optilight CL - Gnatus and Elipar Freelight - 3M/ESPE. RESULTS: Comparing the results by analysis of variance, the Gnatus LED device showed an inferior statistical behavior in relation to other light sources, when activated by a short time. But, when it was used for 40 seconds, the polymerization results were consistent with the other evaluated sources. The device with the best average performance was the halogen light, followed by the 3M/ESPE LED. CONCLUSION: It was concluded that the LEDs may be indicated in orthodontic practice, as long as a protocol is used for the application of light with the activation time of 40 seconds.INTRODUÇÃO: os aparelhos de fotopolimerização por LED buscam proporcionar uma luz ativadora fria, que possibilite protocolos de polimerização do material com menor tempo de duração. OBJETIVO: avaliar a resistência à tração da colagem de braquetes, utilizando três tipos de aparelhos fotoativadores: um de luz halógena (Optilight Plus - Gnatus e outros dois de LED (Optilight CL - Gnatus; e Elipar Freelight - 3M/Espe. RESULTADOS: comparando os resultados por meio da análise de variância, o aparelho de LED Gnatus apresentou comportamento estatístico inferior em relação às outras fontes de luz, quando ativado por tempo reduzido. Já quando foi utilizado o tempo de 40 segundos, os resultados de polimerização foram compatíveis com as demais fontes avaliadas. O aparelho que apresentou melhor desempenho médio foi o de luz halógena, seguido pelo LED 3M/Espe. CONCLUSÃO: concluiu-se que os LEDs podem ser indicados na prática ortodôntica, uma vez que seja utilizado um protocolo de aplicação da luz com tempo de ativação de 40 segundos.

Paulo Eduardo Guedes Carvalho

2013-02-01

179

Bacterial colonization associated with fixed orthodontic appliances. A scanning electron microscopy study.  

Science.gov (United States)

This investigation was undertaken to assess bacterial plaque accumulation adjacent to orthodontic brackets. Experiments were carried out on 11 subjects who were scheduled for orthodontic treatment including extraction of two or four premolars. Metal brackets were bonded to the premolars to be extracted using macro-filled bonding composite. A conventional elastomeric ring was placed around one bracket and a steel ligature wire around the bracket on the contralateral tooth. The subjects were told to continue their normal oral hygiene regimen. Teeth were extracted at 1, 2, or 3 weeks after bracket bonding. Scanning electron microscopic (SEM) examination of brackets, excess composite, and buccal enamel revealed that mature plaque was present on excess composite at 2 and 3 weeks after bonding, whereas plaque on the gingival enamel surface was still at an early stage of development. The results demonstrate that excess composite around the bracket base is the critical site for plaque accumulation due to its rough surface and the presence of a distinct gap at the composite-enamel interface. The method of ligation does not appear to influence the bacterial morphotypes on both composite and enamel surfaces. PMID:11668867

Sukontapatipark, W; el-Agroudi, M A; Selliseth, N J; Thunold, K; Selvig, K A

2001-10-01

180

[Preprosthetic orthodontic treatments].  

Science.gov (United States)

The objective of a preprosthetic orthodontic treatment is to position the teeth in such a way that a treatment with (fixed) dental prostheses is made possible or simplified or to affect the result of this treatment positively. Conceivable preprosthetic orthodontic treatments are: correcting primary orthodontic anomalies, closing or reducing interdental spaces and correcting the migration of teeth. In the case of unfavourable maxillomandibular relations, a preprosthetic surgical treatment is usually needed together with a preprosthetic orthodontic treatment. For children with agenesis and/or early loss of teeth and/or aberrant morphology of teeth, a treatment with fixed dental prostheses, either implant-supported or not, may be indicated after the tooth development or in some cases earlier. Until that time, preprosthetic orthodontic treatments may be indicated to offer an aesthetically sound provisional solution and to achieve optimal teeth positions for the final fixed dental prostheses. PMID:24684136

Prahl-Andersen, B; Prahl, C; de Baat, C; Creugers, N H J

2014-03-01

181

Effect of light-curing units in shear bond strength of metallic brackets: an in vitro study  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVES: To determine the influence of the light curing units on the shear bond strength of orthodontic brackets. MATERIAL AND METHODS: Seventy-two premolars were divided into six groups (n=12: Group I: brackets bonded with Transbond and polymerization with halogen light; Group II: Transbond and LED; Group III: Fuji Ortho and halogen light; Group IV: Fuji Ortho and LED; Group V: Fuji Ortho, without acid and halogen light; Group VI: Fuji Ortho, without acid and LED. The groups were tested to shear strength in a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test. RESULTS: The composite resin presented higher shear bond strength than the resin-modified glass ionomer cement (p0.05. CONCLUSION: The shear bond strength was influenced by the material but not by the light-curing unit. The use of LED reduced the experimental time by approximately 60%, with the same curing efficiency.

Luciana Borges Retamoso

2010-02-01

182

Effect of light-curing units in shear bond strength of metallic brackets: an in vitro study  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVES: To determine the influence of the light curing units on the shear bond strength of orthodontic brackets. MATERIAL AND METHODS: Seventy-two premolars were divided into six groups (n=12): Group I: brackets bonded with Transbond and polymerization with halogen light; Group II: Transbond and [...] LED; Group III: Fuji Ortho and halogen light; Group IV: Fuji Ortho and LED; Group V: Fuji Ortho, without acid and halogen light; Group VI: Fuji Ortho, without acid and LED. The groups were tested to shear strength in a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test. RESULTS: The composite resin presented higher shear bond strength than the resin-modified glass ionomer cement (p0.05). CONCLUSION: The shear bond strength was influenced by the material but not by the light-curing unit. The use of LED reduced the experimental time by approximately 60%, with the same curing efficiency.

Luciana Borges, Retamoso; Niége Michelle Lazzari, Onofre; Luciane, Hann; Ernani Menezes, Marchioro.

2010-02-01

183

Glass transition and degree of conversion of a light-cured orthodontic composite  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: This study evaluated the glass transition temperature (Tg) and degree of conversion (DC) of a light-cured (Fill Magic) versus a chemically cured (Concise) orthodontic composite. MATERIAL AND METHODS: Anelastic relaxation spectroscopy was used for the first time to determine the Tg of a de [...] ntal composite, while the DC was evaluated by infrared spectroscopy. The light-cured composite specimens were irradiated with a commercial LED light-curing unit using different exposure times (40, 90 and 120 s). RESULTS: Fill Magic presented lower Tg than Concise (35-84ºC versus 135ºC), but reached a higher DC. CONCLUSIONS: The results of this study suggest that Fill Magic has lower Tg than Concise due to its higher organic phase content, and that when this light-cured composite is used to bond orthodontic brackets, a minimum energy density of 7.8 J/cm² is necessary to reach adequate conversion level and obtain satisfactory adhesion.

Michela M. D. S., Sostena; Renata A., Nogueira; Carlos R., Grandini; João Carlos Silos, Moraes.

2009-12-01

184

Glass transition and degree of conversion of a light-cured orthodontic composite  

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Full Text Available OBJECTIVE: This study evaluated the glass transition temperature (Tg and degree of conversion (DC of a light-cured (Fill Magic versus a chemically cured (Concise orthodontic composite. MATERIAL AND METHODS: Anelastic relaxation spectroscopy was used for the first time to determine the Tg of a dental composite, while the DC was evaluated by infrared spectroscopy. The light-cured composite specimens were irradiated with a commercial LED light-curing unit using different exposure times (40, 90 and 120 s. RESULTS: Fill Magic presented lower Tg than Concise (35-84ºC versus 135ºC, but reached a higher DC. CONCLUSIONS: The results of this study suggest that Fill Magic has lower Tg than Concise due to its higher organic phase content, and that when this light-cured composite is used to bond orthodontic brackets, a minimum energy density of 7.8 J/cm² is necessary to reach adequate conversion level and obtain satisfactory adhesion.

Michela M. D. S. Sostena

2009-12-01

185

Shear bond strength of new and recycled brackets to enamel  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo deste estudo foi avaliar in vitro a resistência ao cisalhamento de bráquetes reciclados. Foram utilizados 50 pré-molares humanos, extraídos com finalidade ortodôntica, nos quais foi feita a colagem de bráquetes (S2C-03Z; Dental Morelli, Brasil) com resina composta quimicamente ativada (Co [...] ncise Ortodôntico; 3M, EUA). Os dentes foram divididos aleatoriamente em 5 grupos (n=10). No grupo I (controle), os bráquetes colados permaneceram fixados até o momento do teste de cisalhamento (ou seja, não foram feitos procedimentos de remoção e nova colagem dos bráquetes). Nos grupos II, III e IV, os bráquetes foram removidos e reutilizados após reciclagem com jateamento de óxido de alumínio (90 µm), desgaste com ponta abrasiva de carboneto de silício ou processo industrial por uma empresa especializada (Abzil-Lancer, Brasil), respectivamente. No grupo V, os bráquetes foram removidos e bráquetes novos foram colados sobre o esmalte. Os ensaios de cisalhamento foram realizados numa máquina Instron com velocidade de 0,5 mm/min e os resultados foram submetidos à análise de variância e teste de Tukey com nível de significância de 5 %. Não houve diferença estatisticamente significante (p>0,05) entre os bráquetes do grupo controle (0,52 kgf/mm²), reciclados com óxido de alumínio (0,34 kgf/mm²) e bráquetes novos colados sobre o esmalte onde anteriormente havia bráquetes fixados (0,43 kgf/mm²). Bráquetes reciclados pela empresa especializada (0,28 kgf/mm²) e pelo desgaste com carboneto de silício (0,14 kgf/mm²) apresentaram os menores valores de resistência ao cisalhamento, com diferença estatisticament significante (p Abstract in english 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 we [...] re 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

Stenyo Wanderley, Tavares; Simonides, Consani; Darcy Flávio, Nouer; Maria Beatriz Borges de Araújo, Magnani; Paulo Roberto Aranha, Nouer; Laura Moura, Martins.

186

Evaluation In Vitro of Frictional Resistance of Self-Ligating Esthetic and Conventional Brackets / Evaluación In Vitro de la Resistencia Friccional en Brackets de Autoligado Estéticos y Convencionales  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish El objetivo fue evaluar la resistencia a la fricción producida en de brackets de autoligado estéticos y convencionales durante la simulación mecánica de deslizamiento ortodóncico. Se utilizaron cuatro tipos diferentes de soportes: 3 de tipo autoligado de diferentes marcas (Clarity SL, 3M Unitek; Dam [...] on 3®, Ormco Corporation; In-Ovation C®, GAC International), además de brackets estéticos convencionales (Radiance®, American Orthodontics) asociado con ligaduras elásticas convencionales (Sani-tie®, GAC International) y ligaduras de baja fricción (Slide®, Leone). Para simular la mecánica de deslizamiento, se utilizaron alambres de acero inoxidable con un espesor de 0,018" y 0,017"x0.025" (GAC Internacional). Cinco grupos (n = 10) fueron sometidos a cinco pruebas mecánicas consecutivas en una máquina de prueba universal modelo Emic DL ® 500. Los resultados mostraron niveles bajos de fricción en todos brackets de autoligado probados y con el uso de alambre de 0.018" (p0,05). Por otra parte, los brackets estéticos convencionales asociados con ligaduras convencionales resultaron tener una mayor resistencia a la fricción con ambos alambres probados (p>0,05). Todos los brackets de autoligado presentan niveles de fricción más bajo que los accesorios convencionales. El brackets activo de autoligado In-Ovation C, demostró un mayor grado de fuerza friccional cuando se asocia con alambre rectangular. La ligadura Slide® puede ser una alternativa al uso de brackets de autoligado. Abstract in english The objective of this study was to evaluate the frictional resistance created in self-ligating esthetic and conventional brackets during simulated orthodontic sliding mechanics. Four different types of brackets were used: 3 self-ligating type of different brands (Clarity SL, 3M Unitek; Damon 3®, Orm [...] co Corporation; In-Ovation C®, GAC International), in addition to conventional esthetic brackets (Radiance®, American Orthodontics) associated with conventional elastic ligatures (Sani-tie®, GAC International) and low friction ligatures (Slide®, Leone). To simulate sliding mechanics, stainless steel wires with thicknesses of 0.018" and 0.017"x0.025" (GAC International) were used. Five groups (n=10) were submitted to five consecutive mechanical tests in a universal test machine model Emic® DL 500. The results showed low frictional levels in all tested self-ligating brackets and with use of 0.018" wire (p0.05). Moreover, conventional esthetic brackets associated with conventional ligatures resulted in greater frictional resistance with both wires tested (p>0.05). All the self-ligating brackets presented lower frictional levels than the conventional accessories. Active self-ligating bracket In-Ovation C, demonstrated higher degree of frictional force when associated with rectangular wire. The Slide® ligature may be an alternative to the use of self-ligating brackets.

Maria Rita Danelon do, Amaral; Perrim Smith, Neto; Matheus Melo, Pithon; Dauro Douglas, Oliveira.

2014-09-01

187

The influence of different types of fixed orthodontic appliance on the growth and adherence of microorganisms (in vitro study).  

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Orthodontic appliances serve as different impact zones and modify microbial adherence and colonization, acting as foreign reserves and possible sources of infection. This study was conducted to investigate the effect of different types of fixed orthodontic appliances on the growth and adherence of microorganisms in oral flora which are Streptococcus mutans (S. mutans) and Candida albicans. Sixty-four of four different fixed orthodontic appliance-samples were used, divided into four groups of sixteen. Type I: Sapphire brackets- Coated wires, type II: Sapphire brackets- Stainless steel wires, type III: Stainless steel brackets- Coated wires and type IV: Stainless steel brackets- Stainless steel wires. Oral strains of S. mutans and Candida albicans were studied in the present study using biochemical test then microbial suspensions were prepared to do the tests of each microorganism including the antimicrobial effects of different appliance-samples on the growth of microorganisms and their adhesion tests. The results showed significant differences between the different appliances in terms of inhibition zone formation (Pesthetic appearance, sapphire brackets and coated arch wire, showed the least adherence of S. mutans and Candida albicans in comparison to other appliances with less esthetic and more metal components. Key words:Orthodontic appliance, Adherence, Streptococcus mutans, Candida albicans. PMID:24455049

Saloom, Hayder F; Mohammed-Salih, Harraa S; Rasheed, Shaymaa F

2013-02-01

188

Improvement of orthodontic friction by coating archwire with carbon nitride film  

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In order to reduce frictional resistance between archwire and bracket during orthodontic tooth movement, carbon nitride (CNx) thin films were deposited on the surface of archwires with ion beam assisted deposition (IBAD). The energy-dispersive X-ray spectrometer (EDS) analysis showed that the CNx film was successfully deposited on the surface of the orthodontic wires. X-ray photoelectron spectroscopy (XPS) analysis suggested that the deposited CNx film was sp{sup 2} carbon dominated structures, and diversiform bonds (N-C, N{identical_to}C, et al.) coexisted in the film. The friction tests indicated that the CNx film significantly reduced the wire-bracket friction both in ambient air and in artificial saliva. The sp{sup 2}C rich structure of the CNx film as well as its protection function for the archwire was responsible for the low friction of the wire-bracket sliding system.

Wei Songbo [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Shao Tianmin, E-mail: shaotm@mail.tsinghua.edu.cn [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Ding Peng [Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing 100081 (China)

2011-10-01

189

Improvement of orthodontic friction by coating archwire with carbon nitride film  

International Nuclear Information System (INIS)

In order to reduce frictional resistance between archwire and bracket during orthodontic tooth movement, carbon nitride (CNx) thin films were deposited on the surface of archwires with ion beam assisted deposition (IBAD). The energy-dispersive X-ray spectrometer (EDS) analysis showed that the CNx film was successfully deposited on the surface of the orthodontic wires. X-ray photoelectron spectroscopy (XPS) analysis suggested that the deposited CNx film was sp2 carbon dominated structures, and diversiform bonds (N-C, N?C, et al.) coexisted in the film. The friction tests indicated that the CNx film significantly reduced the wire-bracket friction both in ambient air and in artificial saliva. The sp2C rich structure of the CNx film as well as its protection function for the archwire was responsible for the low friction of the wire-bracket sliding system.

190

The effect upon friction of the degradation of orthodontic elastomeric modules.  

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Orthodontic elastomeric modules are susceptible to degradation and deformation after time in the mouth. The aims of this study were to determine whether degradation of elastomeric modules significantly affects friction during sliding mechanics and to investigate whether there is a difference in the behaviour of elastomeric modules after storage in both in vivo and in vitro environments. An Instron testing machine was used to determine the friction generated by elastomeric modules on 0.019 × 0.025 inch stainless steel archwires at 4 degrees of bracket tip. Four brands of modules were tested straight from the packet (n = 15), after storage in artificial saliva (n = 15), and after being in patients' mouths (n = 32). Modules were tested after 24 hours, 1 week, and 6 weeks after storage in both in vivo and in vitro. Analysis of variance revealed that the degradation of elastomeric modules had a variable affect upon friction and that each storage medium produced a distinct pattern of frictional resistance. Modules stored in artificial saliva experienced a significant reduction in friction (P < 0.001) while modules collected from patients' mouths produced similar friction to modules tested straight from the packet. TP Super Slick® modules under dry test conditions produced significantly greater friction than the other three types of test modules (P < 0.001). The structure and surface characteristics of elastomeric modules may affect frictional resistance when a bracket slides along an archwire. These effects vary according to time, storage medium, and brand of elastomeric material. PMID:21771803

Edwards, Ian Robert; Spary, David John; Rock, William Peter

2012-10-01

191

Relationship between friction force and orthodontic force at the leveling stage using a coated wire  

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Full Text Available SciELO Brazil | Language: English Abstract in english The relationship between orthodontic force and friction produced from an archwire and brackets affects the sliding of the wire in the leveling stage. Objective: The purpose of this study was to evaluate the relationship between force and friction in a small esthetic nickel-titanium (Ni-Ti) wire. [...] Material and Methods: Five esthetic wires (three coated and two plated) and two small, plain Ni-Ti wires (0.012 and 0.014 inches) were used. We performed a three-point bending test according to ISO 15841 and the drawing test with a dental arch model designed with upper linguoversion of the lateral incisor in the arch (displacements of 0.5, 1.0, 2.0 and 3.0 mm), and evaluated the relationship between them. Results: Unloading bending forces of all wires at displacements of less than 1.0 mm were larger than friction forces, but all friction forces at displacements exceeding 2.0 mm were larger than unloading bending forces. The arch likely expands when displacement from the proximal brackets exceeds 1.0 mm. The friction force of a martensite 0.014-inch Ni-Ti wire was significantly greater than those of the other esthetic and austenitic wires. Conclusions: A wire with the smallest possible friction force should be used in cases with more than 1.0 mm displacement.

Masaki, MURAYAMA; Yasuhiro, NAMURA; Takahiko, TAMURA; Hiroaki, IWAI; Noriyoshi, SHIMIZU.

2013-12-01

192

Comparison of personality traits, attitude toward orthodontic treatment, and pain perception and experience before and after orthodontic treatment.  

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ABSTRACT Objective: To compare personality traits, attitude toward orthodontic treatment, and pain perception and experience before and after orthodontic treatment. Materials and Methods: One hundred subjects (50 male and 50 female) were included in this study. The mean (SD) age was 17.5 (2.05) years at T1 and 19.15 (2.32) years at T2. The instruments for data collection were questionnaires that included assessment of patients' personality traits, attitudes toward orthodontic treatment, and pain perception/experience. Subjects completed the questionnaires at two different times: before orthodontic treatment (T1) and after fixed orthodontic treatment (T2). Subjects were treated by fixed orthodontic appliances for an average (SD) period of 18.64 (0.35) months. Paired sample t-test and chi-square test were used to detect any differences. Results: Significant changes in personality traits were detected after orthodontic treatment irrespective of gender. Neuroticism, openness, agreeableness, and conscientiousness scores were improved (P < .001). A positive attitude toward orthodontic treatment was reported at T1 (4.31 [±1.26]) and improved at T2 (3.98 [±1.16]) irrespective of gender (P < .05). The average (SD) expected pain score (T1) was 4.73 (1.88) and the average (SD) experienced pain score (T2) was 4.63 (1.58). Significant difference in the expected and experienced pain scores was not detected (P ?=? .11). Conclusions: Personality traits and attitude toward orthodontic treatment improved after orthodontic treatment. Reported actual pain experience during orthodontic treatment was similar to that expected before treatment. PMID:25279723

Abu Alhaija, Elham S; Abu Nabaa, Mona A; Al Maaitah, Emad F; Al-Omairi, Mahmoud K

2014-10-01

193

Minor Periodontal Surgical Procedures Associated with Orthodontic Treatment  

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Full Text Available In recent years, advances in techniques and dental materials as well as a growing public interest in developing and maintaining a healthy and attractive smile, has resulted in a greater understanding of the interrelationships between periodontics and orthodontics. A multidisciplinary approach is often necessary to treat and prevent dental problems in patients. Orthodontics and Periodontics are interrelated in a variety of situations. Orthodontic instrumentation may be necessary in certain situations for a successful restoration of periodontal health as well as for satisfactory maintenance of tissue integrity. At par successful orthodontic treatment for many patients will depend on the periodontal preparation before and after treatment and the maintenance of periodontal health throughout all phases of mechanotherapy. However this article will be mainly concentrating on the minor periodontal surgical procedures which would render optimal orthodontic therapeutic results. This makes an interdisciplinary approach a paramount in achieving a predictable outcome.

Ruchi Banthia

2010-07-01

194

Internet and Orthodontics.  

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Full Text Available Internet is spreading at on incredible rate. Orthodontics has already started adapting to this new environment and future developments are something to look forward to. This article presents main addresses directly or indirectly related to orthodontics. Because of the Web dynamics, changes occur so fast that some addresses may not be valid by the time this article is published and there may be new ones that are not included.

P. Karvelas

1998-01-01

195

Laser diagnostics in orthodontics  

Science.gov (United States)

The results of statistical analysis of Doppler spectra of intensity fluctuations of light, scattered from mucose membrane of oral cavity of healthy volunteers and patients, abused by the orthodontic diseases, are presented. Analysis of Doppler spectra, obtained from tooth pulp of patients, is carried out. New approach to monitoring of blood microcirculation in orthodontics is suggested. Influence of own noise of measuring system on formation of the speckle-interferometric signal is studied.

Ryzhkova, Anastasia V.; Lebedeva, Nina G.; Sedykh, Alexey V.; Ulyanov, Sergey S.; Lepilin, Alexander V.; Kharish, Natalia A.

2003-10-01

196

Internet and Orthodontics.  

OpenAIRE

Internet is spreading at on incredible rate. Orthodontics has already started adapting to this new environment and future developments are something to look forward to. This article presents main addresses directly or indirectly related to orthodontics. Because of the Web dynamics, changes occur so fast that some addresses may not be valid by the time this article is published and there may be new ones that are not included.

Karvelas, P.

1998-01-01

197

Plaque Index in Multi-Bracket Fixed Appliances  

International Nuclear Information System (INIS)

To compare the plaque index in patients receiving multi-bracket fixed orthodontic treatment for various factors like age, gender, socio-economic status, brushing practices, meal habits, types of brackets, types of ligations, use of mouthwash and duration of treatment. Study Design: Cross-sectional analytical study. Place and Duration of Study: Orthodontics Clinic, The Aga Khan University Hospital, from September to November 2011. Methodology: Socio-demographic and clinical modalities were defined and recorded for 131 patients having multi-bracket fixed appliances. The plaque index of subjects were recorded according to the Silness and Loe plaque index method. Independent sample t-test was used to see difference in plaque index in factors having two variables. One way ANOVA and Post-Hoc Tukey tests were used to see difference in plaque index in factors having three variables. Kappa statistics was used to assess inter examiner reliability. P-value 0.05 was taken to be significant. Results: The sample comprised of 37% males (n = 48) and 63% females (n = 83). The plaque index had statistically significant association with practice of brushing i.e., timing of brushing (p=0.001), method of brushing (p=0.08), type of ligatures (p=0.05) and frequency of visits (p=0.01). Conclusion: The plaque accumulation is significantly decreased in subjects who brush the teeth twice or more than twice a day and those who brush their teeth after breakfast. The use of interdental brush and stainless steel ligatures had significantly low plaque. Subjects presenting with more frequent appointments of short-period had significantly less plaque. (author)

198

Beta titanium: a new orthodontic alloy.  

Science.gov (United States)

Historically, few alloys have been used in the fabrication of orthodontic appliances. This article reviews the gold-based, stainless steel, chrome-cobalt-nickel, and nitinol alloys, as well as beta titanium, a new material for orthodontics. Mechanical properties and manipulative characteristics are summarized to develop a basis for the selection of the proper alloy for a given clinical situation. The beta titanium wire has a unique balance of low stiffness, high springback, formability, and weldability which indicates its use in a wide range of clinical applications. A number of such applications are described. PMID:6928342

Burstone, C J; Goldberg, A J

1980-02-01

199

[Changes in the enamel after in vitro debonding of brackets bonded with a modified glass ionomer cement].  

Science.gov (United States)

The aim of this study was to assess the incidence on the enamel behavior of debonding two types of orthodontic brackets, bonded with two different adhesives. Ninety recently extracted human premolars were bonded with two types of brackets (30 Minitrim and 60 Discovery). Two bonding protocols were used. The first one consisted in bonding 30 Minitrim and 30 Discovery brackets on etched and dried enamel surfaces with No Mix orthodontic resin. The second one consisted in bonding 30 Discovery brackets on unetched and wet enamel surfaces with a modified glass ionomer cement, Fuji Ortho LC. Teeth were stored in hydrated ambiance at 37 degrees C for 7 days before debonding. A LLOYD (LR 30K) testing machine was used to evaluate the orthogonal tensile bond strength. The debonded base brackets were examined with a scanning electron microscope (JEOL JSM 6400) and qualitatively analyzed with an OXFORD-LINK-ISIS to assess the site of bond failure and the enamel detachments. An Enamel Detachment Index (EDI) was defined. The results showed that the types of orthodontics brackets and adhesives influenced the bond strength and the enamel detachment. The Discovery/No Mix couple presented higher bond strength (214.9 N) than observed with the Discovery/Fuji Ortho LC (98.5 N) or the Minitrim/No Mix (82.3 N) couples. The surfaces of enamel detachment were insignificant and not extended for all brackets. Nevertheless, the Discovery/No Mix couple presented 42% of an EDI score of 1, compared to the Discovery/Fuji Ortho LC and Minitrim/No Mix couples which presented, respectively, 8% an 20% of an EDI score of 1. The laser sculpted base (Discovery) bonded on unetched and wet enamel surfaces with the modified glass ionomer cement (Fuji Ortho LC) offers a good resistance to debonding forces and preserve enamel integrity. PMID:10916640

Sorel, O; el Alam, R; Chagneau, F; Cathelineau, G

2000-04-01

200

Degradation of orthodontic wires under simulated cariogenic and erosive conditions  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english This study examined the effect of cariogenic and erosive challenges (CCs and ECs, respectively) on the degradation of copper-nickel-titanium (CuNiTi) orthodontic wires. Sixty wire segments were divided into four treatment groups and exposed to CCs, ECs, artificial saliva, or dry storage (no-treatmen [...] t control). CC and EC were simulated using a demineralizing solution (pH 4.3) and a citric acid solution (pH 2.3), respectively. Following treatment, the average surface roughness (Ra) of the wires was assessed, and friction between the wires and a passive self-ligating bracket was measured. CuNiTi wires subjected to ECs exhibited significantly higher Ra values than did those that were stored in artificial saliva. In contrast, surface roughness was not affected by CCs. Finally, friction between the treated wires and brackets was not affected by ECs or CCs. Our results indicate that CuNiTi orthodontic wires may suffer degradation within the oral cavity, as ECs increased the surface roughness of these wires. However, rougher surfaces did not increase friction between the wire and the passive self-ligating bracket.

Laura Cavalcante Lima, JABER; José Augusto, RODRIGUES; Flávia Lucisano Botelho, AMARAL; Fabiana Mantovani Gomes, FRANÇA; Roberta Tarkany, BASTING; Cecilia Pedroso, TURSSI.

2014-08-04

201

The Bracketless Fixed Orthodontics: nine years of clinical experimentation.  

Science.gov (United States)

The Bracketless Fixed Orthodontics (BFO) is an innovative appliance made up of wires and resin. It comes from the observation of the instable position of frontal teeth still bonded to a fixed retainer and from a period of nine year of clinical experimentation on a way to preactivate a wire to obtain a wished dental movements without brackets. For this historical reasons the first experimental name was: Preactivated Retainers. It can be used to levelling teeth, as in case of relapse, or to remove the brackets before the end of the therapy. But it can be used also in more complicated clinical cases in patient that never have been treated with orthodontic therapy, alone or associated to other appliances. In this article are showed only some exemplificative clinical cases. The resolution of crowded teeth, the torque correction and the closing diastema. This appliance applied whether on the buccal aspect or on the lingual aspect of the teeth offers different advantages, as it guarantees a good control of the dental movement, also in the root movement, does not interfere in patients' phonetics and does not interfere in oral hygiene. Since don't exist neither precise references, like brackets, nor a codified therapeutic sequence the best results could be achieved accurately applying the principles of biomechanics described by Burstone and Melsen in their segmented approach. PMID:19294242

Musilli, Marino

2008-01-01

202

Viscoelastic properties of an aesthetic translucent orthodontic wire.  

Science.gov (United States)

The objective of this study was to evaluate the time-dependent viscoelastic properties of an aesthetic orthodontic archwire. The wire is based on a recently developed translucent polyphenylene thermoplastic, whose rigid molecular structure provides high strength. While the wire has good instantaneous mechanical properties, over time all polymers may relax so it is important to understand the potential impact of the relaxation on orthodontic force systems. Four samples of 0.020 inch round and six samples of 0.021 × 0.025 inch rectangular wire were loaded in tension to a range of initial stresses, and relaxation of the stress was monitored for 7 days. Sixty-three additional samples were maintained in edgewise bracket pairs with vertical displacement for up to 6 weeks. The deformation of these wires was measured immediately after removal from the brackets and for 2 days as the samples recovered. Tensile stress decayed about 10-30 per cent over 24-48 hours depending on the initial stress. The relaxation behaviour was proportional to the initial tensile strain and therefore these data were combined into a single curve using regression. Deformation of the samples placed in the bracket pairs increased with increasing vertical displacement and time, evaluated with analysis of variance, but 19-100 per cent of the deformation was recoverable. The force systems from polyphenylene wires could vary with time and activation, but this behaviour is predictable. PMID:21159774

Goldberg, A Jon; Liebler, Stephenie A H; Burstone, Charles J

2011-12-01

203

Tips for maintaining sterilization in your orthodontic work station.  

Science.gov (United States)

Sterilization and disinfection have been a matter of concern amongst dental health care workers since long. Delicate materials, electrical parts, orthodontic pliers, orthodontic wire cutters, are to be treated according to the manufacturer's instructions to safe guard the life of the instrument as well as to claim warranty for any damage incurred. Sterilization procedures used in Orthodontics should be simple but effective and of relatively short duration so that there is a readily available supply of sterile instruments and materials. The procedure should not cause any appreciable damage to dental instruments and other materials. An attempt has been made through this article, to provide information concerning methods and means of disinfection and sterilization of orthodontic clinics, instruments, materials and also waste disposal which can be adopted in private clinics as well as in hospital set ups. PMID:25109055

Batra, Panchali; Jyothikiran, H

2014-01-01

204

Evaluation of shear bond strength of different treatments of ceramic bracket surfaces / Avaliação da resistência ao cisalhamento de diferentes tratamentos na superfície de braquetes cerâmicos  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: avaliar a resistência à união da interface entre braquete cerâmico e restauração de resina composta, empregando quatro tipos de tratamento na base do braquete. MÉTODOS: foram utilizados 48 discos de resina fotoativada (Filtek® Z250) incluídos em corpos de prova, divididos em quatro grupos, [...] com 12 espécimes em cada grupo, de acordo com o tipo de tratamento realizado na base do braquete. Uma vez colados os braquetes, os corpos de prova foram submetidos à tensão de cisalhamento, realizado numa máquina universal de ensaios (MTS: 810 Material Test System) calibrada com velocidade fixa de 0,5mm/min. Os valores obtidos foram registrados e comparados por meio de médias, utilizando-se testes estatísticos adequados (análise de Variância e, posteriormente, teste de Tukey). RESULTADOS E CONCLUSÕES: o condicionamento das superfícies dos braquetes cerâmicos com ácido hidrofluorídrico a 10% por 1 minuto, seguido do jateamento com óxido de alumínio com 50um de tamanho, e posterior aplicação do silano e, depois, aplicação de adesivo, foi considerado o melhor método para o preparo de superfícies de braquetes cerâmicos previamente à colagem estética ortodôntica. Abstract in english OBJECTIVE: To evaluate the bonding strength of the ceramic bracket and composite resin restoration interface, using four types of treatment on the base of the bracket. METHODOLOGY: 48 photoactivated composite resin discs were used (FiltekTM Z250) contained in specimens and divided into 4 groups of 1 [...] 2 specimens for each group according to the type of treatment performed on the base of the brackets. Once the brackets were bonded, the specimens were subjected to shear stress carried out in a universal testing machine (MTS: 810 Material Test System) calibrated with a fixed speed of 0.5 mm / minute. The values obtained were recorded and compared by means of appropriate statistical tests - analysis of variance and then Tukey's test. RESULTS AND CONCLUSIONS: The surfaces of ceramic brackets conditioned with 10% hydrofluoric acid for 1 minute, followed by aluminum oxide blasting, 50µ, after silane application and primer application, was considered the best method to prepare surfaces of ceramic brackets prior to orthodontic esthetic bonding.

Patrícia Helou Ramos, Andrade; Rogério Vieira, Reges; Marcos Augusto, Lenza.

2012-08-01

205

Evaluation of shear bond strength of different treatments of ceramic bracket surfaces Avaliação da resistência ao cisalhamento de diferentes tratamentos na superfície de braquetes cerâmicos  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: To evaluate the bonding strength of the ceramic bracket and composite resin restoration interface, using four types of treatment on the base of the bracket. METHODOLOGY: 48 photoactivated composite resin discs were used (FiltekTM Z250 contained in specimens and divided into 4 groups of 12 specimens for each group according to the type of treatment performed on the base of the brackets. Once the brackets were bonded, the specimens were subjected to shear stress carried out in a universal testing machine (MTS: 810 Material Test System calibrated with a fixed speed of 0.5 mm / minute. The values obtained were recorded and compared by means of appropriate statistical tests - analysis of variance and then Tukey's test. RESULTS AND CONCLUSIONS: The surfaces of ceramic brackets conditioned with 10% hydrofluoric acid for 1 minute, followed by aluminum oxide blasting, 50µ, after silane application and primer application, was considered the best method to prepare surfaces of ceramic brackets prior to orthodontic esthetic bonding.OBJETIVO: avaliar a resistência à união da interface entre braquete cerâmico e restauração de resina composta, empregando quatro tipos de tratamento na base do braquete. MÉTODOS: foram utilizados 48 discos de resina fotoativada (Filtek® Z250 incluídos em corpos de prova, divididos em quatro grupos, com 12 espécimes em cada grupo, de acordo com o tipo de tratamento realizado na base do braquete. Uma vez colados os braquetes, os corpos de prova foram submetidos à tensão de cisalhamento, realizado numa máquina universal de ensaios (MTS: 810 Material Test System calibrada com velocidade fixa de 0,5mm/min. Os valores obtidos foram registrados e comparados por meio de médias, utilizando-se testes estatísticos adequados (análise de Variância e, posteriormente, teste de Tukey. RESULTADOS E CONCLUSÕES: o condicionamento das superfícies dos braquetes cerâmicos com ácido hidrofluorídrico a 10% por 1 minuto, seguido do jateamento com óxido de alumínio com 50um de tamanho, e posterior aplicação do silano e, depois, aplicação de adesivo, foi considerado o melhor método para o preparo de superfícies de braquetes cerâmicos previamente à colagem estética ortodôntica.

Patrícia Helou Ramos Andrade

2012-08-01

206

Effect of different enamel conditionings on the bond strength of glass ionomer cement and ceramic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Aim: To evaluate the effect of different enamel conditionings on the shear bond strength (SBS) and bond failure patterns of a resin modified glass ionomer cement (RMGIC) used to bond ceramic brackets. Methods: 105 human premolars extracted for orthodontic reasons were divided into 7 groups according [...] to the enamel surface treatments: conditioners (35% phosphoric acid and 10% polyacrylic acid), type of adhesive (Transbond(r) and Fuji Ortho LC Capsule(r)), washing time and drying of the surface. Results: A significant p0.05) to the group that had brackets bonded with composite resin. The two groups that had enamel prepared with polyacrylic acid and brackets bonded with GIC on a wet surface showed significantly lower shear bond strength than the control group (p

Dauro Douglas, Oliveira; Thomas Gerard, Bradley; Matheus Melo, Pithon; Mariele Cristina Garcia, Pantuzo; Emílio, Akaki; Virendra, Dhuru.

2014-12-01

207

Avaliação da resistência ao cisalhamento de braquetes da técnica lingual colados sobre superfície cerâmica / Evaluation of shear strength of lingual brackets bonded to ceramic surfaces  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: avaliar a resistência ao cisalhamento de braquetes metálicos (American Orthodontics) utilizados na técnica lingual, colados em facetas de cerâmica. MÉTODOS: foram utilizados 40 corpos de prova divididos em quatro grupos de 10, de acordo com o material de colagem e do preparo da porcelana: [...] Grupo I -resina Sondhi Rapid-Set e ácido fluorídrico; Grupo II -resina Sondhi Rapid-Set e óxido de alumínio; Grupo III -resina Transbond XT e ácido fluorídrico; e Grupo IV -resina Transbond XT e óxido de alumínio. Previamente à colagem, os braquetes foram preparados com base de resina de carga pesada (Z-250) e as facetas de cerâmica receberam aplicação de silano. O teste de cisalhamento foi realizado por uma máquina de ensaios Kratos à uma velocidade de 0,5mm/min. RESULTADOS: os resultados obtidos foram analisados estatisticamente através do teste de Tukey (p Abstract in english OBJECTIVE: The aim of this study was to evaluate the shear strength of lingual metal brackets (American Orthodontics) bonded to ceramic veneers. METHODS: A total of 40 specimens were divided into four groups of 10, according to bonding material and ceramics preparation: Group I -Sondhi Rapid-Set res [...] in and Hydrofluoric acid, Group II -Sondhi Rapid-Set resin and aluminum oxide, Group III -Transbond XT resin and Hydrofluoric acid, and Group IV -Transbond XT resin and aluminum oxide. Prior to bonding, the brackets were prepared with heavy-duty resin base (Z-250) and the ceramic veneers were treated with silane. The shear test was conducted with a Kratos testing machine at a speed of 0.5 mm/min. RESULTS: The results were statistically analyzed by the Tukey test (p

Michele Balestrin, Imakami; Karyna Martins, Valle-Corotti; Paulo Eduardo Guedes, Carvalho; Ana Carla Raphaelli Nahás, Scocate.

2011-06-01

208

Orthodontic rare earth magnets--in vitro assessment of cytotoxicity.  

Science.gov (United States)

The aim of this study was to assess and compare in vitro the cytotoxic effects of uncoated and parylene-coated rare earth magnets, used in orthodontics. Cytotoxicity of samarium-cobalt magnets (SmCo5 and Sm2Co17) and neodymium-iron-boron magnets (Nd2Fe14B) was assessed by two in vitro methods, the millipore filter method and an extraction method. Orthodontic stainless steel brackets served as controls. Uncoated SmCo5-magnets showed high cytotoxicity while uncoated Sm2Co17-magnets demonstrated moderate cytotoxicity. Uncoated neodymium-iron-boron magnets, as well as parylene coated Sm2Co17-magnets and parylene-coated neodymium-iron-boron magnets, showed negligible cytotoxicity. Short-term exposure to a static magnetic field did not cause any cytotoxic effect on the cells. PMID:7857892

Bondemark, L; Kurol, J; Wennberg, A

1994-11-01

209

Mechanical properties of a new thermoplastic polymer orthodontic archwire.  

Science.gov (United States)

A new thermoplastic polymer for orthodontic applications was obtained and extruded into wires with round and rectangular cross sections. We evaluated the potential of new aesthetic archwire: tensile, three point bending, friction and stress relaxation behaviour, and formability characteristics were assessed. Stresses delivered were generally slightly lower than typical beta-titanium and nickel-titanium archwires. The polymer wire has good instantaneous mechanical properties; tensile stress decayed about 2% over 2h depending on the initial stress relaxation for up to 120h. High formability allowed shape bending similar to that associated with stainless steel wires. The friction coefficients were lower than the metallic conventional archwires improving the slipping with the brackets. This new polymer could be a good candidate for aesthetic orthodontic archwires. PMID:25063084

Varela, Juan Carlos; Velo, Marcos; Espinar, Eduardo; Llamas, Jose Maria; Rúperez, Elisa; Manero, Jose Maria; Javier Gil, F

2014-09-01

210

Complications of orthodontic treatment: are soft drinks a risk factor?  

Science.gov (United States)

Soft drink consumption has steadily increased in recent decades in both western and developing countries. The trend is most apparent among children and adolescents. This rise in soft drink consumption has raised concerns among health care professionals, including dental practitioners. Accordingly, the effects of soft drinks on dental health have been investigated. Several studies have shown that dental problems, such as caries, enamel erosion, and corrosion of dental materials, may be associated with soft drink consumption. Because orthodontic appliances restrict toothbrush access, patients undergoing orthodontic treatment need special oral care and advice. This article reviews the risks and implications of soft drink consumption for orthodontic patients. PMID:19388431

Yip, Hilings H Y; Wong, Ricky W K; Hägg, Urban

2009-01-01

211

Long-term fluoride release from resin-reinforced orthodontic cements following recharge with fluoride solution  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo deste estudo foi testar a hipótese que não há diferença no desempenho dos cimentos de ionômero de vidro reforçados com resina entre si quanto à liberação de flúor antes e após recarga com flúor. Os materiais foram divididos em 5 grupos: 2 cimentos de ionômero de vidro reforçados com resin [...] a utilizados para cimentação de bandas ortodônticas: Grupo FOB (Fuji Ortho Band) e Grupo MCB (Multi-Cure Glass Ionomer Orthodontic Band Cement); 2 cimentos de ionômero de vidro reforçados com resina e 1 compósito utilizados para colagem de bráquetes ortodônticos: Grupo OGLC (Ortho Glass LC), Grupo FOLC (Fuji Ortho LC); e Grupo TXT (Transbond XT), respectivamente. A liberação de flúor foi medida durante 60 dias, através de eletrodo íon seletivo conectado a um analisador de íons. Após 4 semanas, os corpos de prova foram expostos a solução de fluoreto de sódio à 0,221%. Os resultados evidenciaram que os cimentos atingiram o pico máximo de liberação de flúor com 24 h após presa inicial. Não houve diferença estatisticamente significante entre a quantidade de flúor liberado após as recargas de fluoreto de sódio entre os grupos FOB e OGLC do 31° ao 36° dia (p>0.05). Concluindo os cimentos FOB e OGLC apresentaram maior capacidade de captação e liberação de flúor comparada aos outros CIVRRs. Abstract in english The aim of this study was to test the hypothesis that there is no difference in the fluoride release behavior of resin-reinforced glass ionomer cements before or after fluoride recharge. The materials were divided into 5 groups: 2 resin-reinforced glass ionomer cements used for attaching orthodontic [...] bands, that is, group FOB (Fuji Ortho Band) and group MCB (Multi-Cure Glass Ionomer Orthodontic Band Cement); 2 resin-reinforced glass ionomer cements and a composite used for bonding orthodontic brackets, that is, group OGLC (Ortho Glass LC), group FOLC (Fuji Ortho LC), and group TXT (Transbond XT), respectively. Fluoride release was measured during a 60-day period by using selective ion electrodes connected to an ionic analyser. After 4 weeks, the samples were exposed to 0.221% sodium fluoride solution. The results showed that cements achieved a maximum fluoride release 24 h after initial setting. No statistically significant differences were observed between groups FOB and OGLC regarding the amount of released fluoride following fluoride recharge from day 31 to day 36 (p>0.05). In conclusion, FOB and OGLC cements showed a higher capacity of capturing and releasing fluoride compared to the other cements studied.

Rogério Lacerda dos, Santos; Matheus Melo, Pithon; Delmo Santiago, Vaitsman; Mônica Tirre de Souza, Araújo; Margareth Maria Gomes de, Souza; Matilde Gonçalves da Cunha, Nojima.

212

Halogen light versus LED for bracket bonding: shear bond strength  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese INTRODUÇÃO: os aparelhos de fotopolimerização por LED buscam proporcionar uma luz ativadora fria, que possibilite protocolos de polimerização do material com menor tempo de duração. OBJETIVO: avaliar a resistência à tração da colagem de braquetes, utilizando três tipos de aparelhos fotoativadores: u [...] m de luz halógena (Optilight Plus - Gnatus) e outros dois de LED (Optilight CL - Gnatus; e Elipar Freelight - 3M/Espe). RESULTADOS: comparando os resultados por meio da análise de variância, o aparelho de LED Gnatus apresentou comportamento estatístico inferior em relação às outras fontes de luz, quando ativado por tempo reduzido. Já quando foi utilizado o tempo de 40 segundos, os resultados de polimerização foram compatíveis com as demais fontes avaliadas. O aparelho que apresentou melhor desempenho médio foi o de luz halógena, seguido pelo LED 3M/Espe. CONCLUSÃO: concluiu-se que os LEDs podem ser indicados na prática ortodôntica, uma vez que seja utilizado um protocolo de aplicação da luz com tempo de ativação de 40 segundos. Abstract in english INTRODUCTION: LED light-curing devices seek to provide a cold light activator which allows protocols of material polymerization with shorter duration. OBJECTIVE: The present study aimed to evaluate the shear bond strength of bracket bonding using three types of light-curing devices: One with halogen [...] light (Optilight Plus - Gnatus) and two with LEDs (Optilight CL - Gnatus and Elipar Freelight - 3M/ESPE). RESULTS: Comparing the results by analysis of variance, the Gnatus LED device showed an inferior statistical behavior in relation to other light sources, when activated by a short time. But, when it was used for 40 seconds, the polymerization results were consistent with the other evaluated sources. The device with the best average performance was the halogen light, followed by the 3M/ESPE LED. CONCLUSION: It was concluded that the LEDs may be indicated in orthodontic practice, as long as a protocol is used for the application of light with the activation time of 40 seconds.

Paulo Eduardo Guedes, Carvalho; Valdemir Muzulon dos, Santos; Hassan, Isber; Flávio Augusto, Cotrim-Ferreira.

2013-02-01

213

Exterior Differentials in Superspace and Poisson Brackets  

OpenAIRE

It is shown that two definitions for an exterior differential in superspace, giving the same exterior calculus, yet lead to different results when applied to the Poisson bracket. A prescription for the transition with the help of these exterior differentials from the given Poisson bracket of definite Grassmann parity to another bracket is introduced. It is also indicated that the resulting bracket leads to generalization of the Schouten-Nijenhuis bracket for the cases of sup...

Soroka, Dmitrij V.; Soroka, Vyacheslav A.

2002-01-01

214

Four Cases of Angular Cheilitis in Orthodontic Patients  

OpenAIRE

Contact dermatitis is an inflammatory reaction of the skin and mucosa to either external or internal factors. It can be divided to two forms of irritant contact dermatitis and allergic contact dermatitis. Nickel is one of the most common materials that causes allergic contact dermatitis and is widely used in orthodontic appliances. The inflammatory reaction to this metal in orthodontics is usually stomatitis and angular cheilitis is very rare. We report 4 cases of angular cheilitis in orthodo...

Kafaie, P.; Yassaei, S.

2006-01-01

215

A Comparison of Apical Root Resorption in Incisors after Fixed Orthodontic Treatment with Standard Edgewise and Straight Wire (MBT Method  

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Full Text Available Statement of Problem: One of the major outcomes of orthodontic treatment is the apical root resorption of teeth moved during the treatment. Identifying the possible risk factors, are necessary for every orthodontist. Purpose: The aim of this study was to compare the rate of apical root resorption after fixed orthodontic treatment with standard edgewise and straight wire (MBT method, and also to evaluate other factors effecting the rate of root resorption in orthodontic treatments.Materials and Method: In this study, parallel periapical radiographs of 127 patients imaging a total of 737 individual teeth, were collected. A total of 76 patients were treated by standard edgewise and 51 patients by straight wire method. The periapical radiographs were scanned and then the percentage of root resorption was calculated by Photoshop software. The data were analyzed by Paired-Samples t-test and the Generalized Linear Model adopting the SPSS 15.0.Results: In patients treated with straight wire method (MBT, mean root resorption was 18.26% compared to 14.82% in patients treated with standard edgewise tech-nique (p< .05. Male patients had higher rate of root resorption,statistically significant (p< .05. Age at onset of treatment, duration of treatment, type of dental occlusion, premolar extractions and the use of intermaxillary elastics had no significant effect on the root resorption in this study.Conclusion: Having more root resorption in the straight wire method and less in the standard edgewise technique can be attributed to more root movement in pre-adjusted MBT technique due to the brackets employed in this method.

Zahed Zahedani SM.

2013-09-01

216

Cephalometry in orthodontic practice  

International Nuclear Information System (INIS)

Cephalometry is applied in orthodontic practice to: - obtain information on the growth of the skull - assist diagnosis of the relationship between the jaws and abnormalities in dentition - evaluate the results of treatment. The course of the diagnostic procedure with the aid of the Ricketts analysis and evaluation of the treatment results using five superimpositions is demonstrated by means of two examples. (Auth.)

217

Burns from orthodontic pliers.  

Science.gov (United States)

A case of burn injury from orthodontic pliers resulting in a partial-thickness burn is presented. A brief description of the injury, a review of the pertinent literature, and general guidelines for out-patient management of such burns are also presented. PMID:21991020

Zagury, A; Baruchin, O; Scharf, S; Baruchin, A M

2006-03-31

218

A influência da variação da curvatura da base do braquete em uma união ortodôntica submetida a diferentes cargas, através do método dos elementos finitos The influence of the variation of the bracket base curvature in a bonded orthodontic attachment submitted by different load cases using the finite element method  

Directory of Open Access Journals (Sweden)

Full Text Available Este trabalho procurou avaliar, através do Método dos Elementos Finitos, a resistência ao deslocamento de quatro diferentes bases de braquetes "straight-wire" (Morelli, Unitek, A-Company e Abzil-Lancer na aplicação de forças de torção e cisalhamento, correlacionando essa resistência à melhor adaptação das bases à superfície vestibular dentária. As curvaturas das bases de braquetes utilizados no presente estudo foram descritas em um estudo prévio, enquanto o contorno dentário foi obtido a partir do escaneamento e cálculo da curvatura média vestibular do canino inferior de uma amostra de 30 indivíduos brasileiros. Empregou-se a análise tridimensional por Elementos Finitos da interface esmalte vestibular/cimento/base do braquete para cada marca testada. Forças de 1N, promovendo deslocamento lateral e torção, foram aplicadas no centro da base do braquete e observou-se a distribuição desses esforços sobre os modelos assim como as tensões normais e de cisalhamento geradas. Os resultados mostraram que a base que melhor se adaptou à superfície vestibular construída foi a da marca Unitek, seguida pela marca A-Company, Abzil-Lancer e Morelli. As deformações sofridas pelos braquetes foram inversamente proporcionais à adaptação à superfície dentária. Os maiores picos de tensão localizaram-se nas proximidades do ponto de aplicação da força. A interface adesivo/esmalte foi mais sujeita à falha na adesão que a interface braquete/adesivo. A força de cisalhamento demonstrou ser mais provável de causar falha na adesão quando comparada à força de torção.The objective of this study was to evaluate the adaptability of the four straight-wire brackets bases (Morelli, Unitek, A-Company and Abzil-Lancer to facial surface of a lower canine. The lower canine facial curvature data to be used in the three-dimensional finite element model were established by 30 Brazilian adult individuals and the brackets bases curvature used were described in a prior study. The three-dimensional finite element analysis of the interface enamel/cement/base of bracket for each tested mark was used. Loads of 1N promoting lateral displacement and torsion had been applied in the center of the base of brackets and the distribution of these efforts on the models was observed as well as the normal and shear tensions generated. The results had shown that the base that better fit to facial surface was the one from Unitek, followed by the A-Company, Abzil-Lancer and Morelli.The brackets deformations were inversely proportional to its adaptation.The biggest peaks of tensions had been situated near to the point of force application. The cement/enamel interface was more likely to fail in the adhesion that the bracket/cement interface. The torsion load was less likely to cause damage in the adhesion when compared with the shear load.

Cláudio Pereira Viana

2005-06-01

219

A influência da variação da curvatura da base do braquete em uma união ortodôntica submetida a diferentes cargas, através do método dos elementos finitos / The influence of the variation of the bracket base curvature in a bonded orthodontic attachment submitted by different load cases using the finite element method  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este trabalho procurou avaliar, através do Método dos Elementos Finitos, a resistência ao deslocamento de quatro diferentes bases de braquetes "straight-wire" (Morelli, Unitek, A-Company e Abzil-Lancer) na aplicação de forças de torção e cisalhamento, correlacionando essa resistência à melhor adapta [...] ção das bases à superfície vestibular dentária. As curvaturas das bases de braquetes utilizados no presente estudo foram descritas em um estudo prévio, enquanto o contorno dentário foi obtido a partir do escaneamento e cálculo da curvatura média vestibular do canino inferior de uma amostra de 30 indivíduos brasileiros. Empregou-se a análise tridimensional por Elementos Finitos da interface esmalte vestibular/cimento/base do braquete para cada marca testada. Forças de 1N, promovendo deslocamento lateral e torção, foram aplicadas no centro da base do braquete e observou-se a distribuição desses esforços sobre os modelos assim como as tensões normais e de cisalhamento geradas. Os resultados mostraram que a base que melhor se adaptou à superfície vestibular construída foi a da marca Unitek, seguida pela marca A-Company, Abzil-Lancer e Morelli. As deformações sofridas pelos braquetes foram inversamente proporcionais à adaptação à superfície dentária. Os maiores picos de tensão localizaram-se nas proximidades do ponto de aplicação da força. A interface adesivo/esmalte foi mais sujeita à falha na adesão que a interface braquete/adesivo. A força de cisalhamento demonstrou ser mais provável de causar falha na adesão quando comparada à força de torção. Abstract in english The objective of this study was to evaluate the adaptability of the four straight-wire brackets bases (Morelli, Unitek, A-Company and Abzil-Lancer) to facial surface of a lower canine. The lower canine facial curvature data to be used in the three-dimensional finite element model were established by [...] 30 Brazilian adult individuals and the brackets bases curvature used were described in a prior study. The three-dimensional finite element analysis of the interface enamel/cement/base of bracket for each tested mark was used. Loads of 1N promoting lateral displacement and torsion had been applied in the center of the base of brackets and the distribution of these efforts on the models was observed as well as the normal and shear tensions generated. The results had shown that the base that better fit to facial surface was the one from Unitek, followed by the A-Company, Abzil-Lancer and Morelli.The brackets deformations were inversely proportional to its adaptation.The biggest peaks of tensions had been situated near to the point of force application. The cement/enamel interface was more likely to fail in the adhesion that the bracket/cement interface. The torsion load was less likely to cause damage in the adhesion when compared with the shear load.

Cláudio Pereira, Viana; Ênio Tonani, Mazzieiro; Janes, Landre Júnior.

2005-06-01

220

Design Modification for Failed Grill Bracket using Finite Element Analysis  

Directory of Open Access Journals (Sweden)

Full Text Available Grill is a part placed on vehicle located in front of the Engine cooling module by means of bracket. The purpose of the Grill is to protect the cooling module from front impact and at the same time provide appropriate aesthetic value to the vehicle. This report presents the failure analysis of grill bracket of Engine cooling module of a Truck using Finite Element Analysis. The Grill bracket has failed in the field before warranty period so it has to be replaced with new one. Replacing old bracket means economic loss to the company. The Failure of this Grill bracket is analysed using Finite Element Analysis. 3 D models were created using Pro –E CAD softwares and Finite element analysis was done using Medina and Permas softwares. After doing Finite Element Analysis it was observed that high stresses were coming at failure location on the Grill bracket. The high stresses were mainly observed due to accelerations loads. Several proposals for alternate designs were created considering the packaging data, availability of the standard materials and manufacturing feasibility. These alternate designs were again checked by finite element analysis. The most optimized design was finalized through this process. The finalized design showed 60% lower stress values at failure location compared to current design. New proposed design was found to pass the given warranty period (100000 miles. Thus Finite element analysis proved to be very suitable tool for the situation where quick solution is expected.

K. S. Kulkarni

2013-03-01

221

The effect of pretreatment with fluoride on the tensile strength of orthodontic bonding  

International Nuclear Information System (INIS)

White spot decalcifications and caries occurring adjacent to bonded orthodontic brackets have long been a concern to orthodontists. One procedure suggested to overcome this problem is fluoride treatment prior to bonding. The purpose of this study was to compare the tensile bond strength of orthodontic self-cured resin from Concise on teeth rinsed 4 minutes in 1.23% APF with untreated controls. Measurements were made on an Instron machine. Debonding interfaces were observed with a scanning electron microscope and energy dispersive x-ray spectrometry. Distributions were calculated. The tensile bond strengths of the fluoride-treated teeth and the untreated teeth were not significantly different. The debonding interfaces between resin and bracket base, within the resin itself, and between enamel and resin were similar in the two experimental groups. However, greater enamel detachment was seen within the fluoride pretreatment group. So while fluoride pretreatment does not significantly affect tensile bond strength, it may cause enamel detachment after debonding

222

Release of Metal Ions from Orthodontic Appliances: An In Vitro Study  

OpenAIRE

In this paper, we report the results of an in vitro experiment on the release of metal ions from orthodontic appliances composed of alloys containing iron, chromium, nickel, silicon, and molybdenum into artificial saliva. The concentrations of magnesium, aluminum, silicon, phosphorus, sulfur, potassium, calcium, titanium, vanadium, manganese, iron, cobalt, copper, zinc, nickel, and chromium were significantly higher in artificial saliva in which metal brackets, bands, and wires used in orthod...

Mikulewicz, Marcin; Chojnacka, Katarzyna; Woz?niak, Barbara; Downarowicz, Patrycja

2012-01-01

223

Backscattering from dental restorations and splint materials during therapeutic radiation  

International Nuclear Information System (INIS)

Models were constructed to simulate as closely as possible the human oral cavity. Radiation absorbed doses were determined for controls and various test situations involving the presence of dental restorative and splint materials during cobalt-60 irradiation of the models. Adjacent gold full crowns and adjacent solid dental silver amalgam cores both increased the dose to the interproximal gingivae by 20%. Use of orthodontic full bands for splinting the jaws increased the dose to the buccal tissues by an average of 10%. Augmentation of dose through backscatter radiation was determined to be only slight for intracoronal amalgam fillings and stainless steel or plastic bracket splints

224

Backscattering from dental restorations and splint materials during therapeutic radiation  

Energy Technology Data Exchange (ETDEWEB)

Models were constructed to simulate as closely as possible the human oral cavity. Radiation absorbed doses were determined for controls and various test situations involving the presence of dental restorative and splint materials during cobalt-60 irradiation of the models. Adjacent gold full crowns and adjacent solid dental silver amalgam cores both increased the dose to the interproximal gingivae by 20%. Use of orthodontic full bands for splinting the jaws increased the dose to the buccal tissues by an average of 10%. Augmentation of dose through backscatter radiation was determined to be only slight for intracoronal amalgam fillings and stainless steel or plastic bracket splints.

Farman, A.G.; Sharma, S.; George, D.I.; Wilson, D.; Dodd, D.; Figa, R.; Haskell, B.

1985-08-01

225

Development of a device to measure bracket debonding force in vivo.  

Science.gov (United States)

The purposes of this study were to develop a device to measure bracket debonding force in vivo and to evaluate, in vitro, the bond strength obtained with the device and with tensile and shear bond strength (SBS) tests performed in a universal testing machine. The device was developed using polypropylene pliers (3M Unitek). The basic principle consisted of measuring the applied force to debond, using two strain gauges (Kyowa) bonded to the region of major deformation of the plier handles. The crowns of 75 bovine incisors were embedded in acrylic resin and orthodontic brackets were bonded to the facial surface with Transbond XT (3M Unitek). In group A (n = 25) debonding was carried out with the device, while tensile bond strength testing was performed in group B (n = 25) and SBS testing in group C (n = 25). A universal testing machine (EMIC-DL-2,000) was used for these last two groups. According to analysis of variance and Tukey's test (alpha = 0.05), the mean bond strength for group C (7.71 MPa) was statistically higher than for groups A (2.98 MPa) and B (2.69 MPa). Groups A and B were not statistically different. The device was shown to be feasible to obtain in vivo bond strength values for orthodontic brackets, and that the bond strength values were dependent on the method and direction of debonding. PMID:17804426

Prietsch, José Renato; Spohr, Ana Maria; Lima da Silva, Isaac Newton; Pinheiro Beck, João Carlos; Silva Oshima, Hugo Mitsuo

2007-12-01

226

A bracket polynomial for graphs  

CERN Document Server

A knot diagram has an associated looped interlacement graph, obtained from the intersection graph of the Gauss diagram by attaching loops to the vertices that correspond to negative crossings. This construction suggests an extension of the Kauffman bracket to an invariant of looped graphs, and an extension of Reidemeister equivalence to an equivalence relation on looped graphs. The graph bracket polynomial can be defined recursively using the same pivot and local complementation operations used to define the interlace polynomial, and it gives rise to a graph Jones polynomial that is invariant under the graph Reidemeister moves.

Traldi, L

2008-01-01

227

Laser Applications in Orthodontics  

Directory of Open Access Journals (Sweden)

Full Text Available A laser is a collimated single wavelength of light which delivers a concentrated source of energy. Soon after different types of lasers were invented, investigators began to examine the effects of different wavelengths of laser energy on oral tissues, routine dental procedures and experimental applications. Orthodontists, along with other specialist in different fields of dentistry, can now benefit from several different advantages that lasers provide during the treatment process, from the beginning of the treatment, when separators are placed, to the time of resin residues removal from the tooth surface at the end of orthodontic treatment. This article outlines some of the most common usages of laser beam in orthodontics and also provides a comparison between laser and other conventional method that were the standard of care prior to the advent of laser in this field.

Somayeh Heidari

2013-09-01

228

Orthodontics : a review  

OpenAIRE

Orthodontics is a branch of dentistry which is concerned with the study of the growth of the craniofacial complex and the occlusion of teeth. It implies the diagnosis, prevention and treatment of abnormalities in these structures. It has been found that only about 25 % of the population has normal occlusions and that 75 % have malocclusions, whether in a lighter or more serious grade. As malocclusion is not a disease, but a result of the variability between the growth and developm...

Muelenaere, J. J. G. G.

1983-01-01

229

Oral health: orthodontic treatment.  

Science.gov (United States)

Improper tooth alignment due to crowding, malocclusion, and missing teeth can cause difficulties with eating and speech, and premature wear. It is estimated that more than 20% of children would benefit from orthodontic treatment to correct these conditions, many of which will persist into adulthood if not corrected. Orthodontic care is gaining popularity among adults for similar concerns, as well as for correction of cosmetic issues. The psychological effects of malocclusion should not be ignored. The American Association of Orthodontists recommends that all children undergo evaluation at the first recognition of an orthodontic condition and no later than age 7 years. Some children will need early treatment to help eliminate developing conditions and improve the foundations of the bite, which can ease later treatment in adolescence. For others, treatment in adolescence without early treatment is recommended. Standard cemented braces or clear, removable aligners may be used, depending on the patient's corrective needs. Average treatment time is approximately 2 years; this may be shortened by the use of accelerative techniques. Routine preventive dental care should be continued during the treatment period. PMID:25594451

Martonffy, Andrea Ildiko

2015-01-01

230

Bonded orthodontic retainers: the wire-composite interface.  

Science.gov (United States)

The bonded orthodontic retainer constructed from multistrand wire and composite is an efficient esthetic retainer, which can be maintained long-term. Clinical failures of bonded orthodontic retainers, most commonly at the wire/composite interface, have been reported. This in vitro investigation aimed to evaluate selected multistrand wires and composite materials that are available for use in the construction of bonded fixed retainers. An in vitro model was developed to simulate the forces encountered at the wire/composite interface. No significant difference was detected between different multistrand wire types and diameters with regard to retention in composite. Wires were placed in one of three groups according to surface characteristics identified with scanning electron microscopy. Increasing the thickness of composite overlying the wire increased the force required to detach the wire from the composite. Thickness of composite greater than 1.0 mm overlying the wire may give little clinical advantage. Greater force was required to detach the wire from Concise Orthodontic (3M Unitek) than any other composite tested. In vitro abrasion resistance testing found Heliosit Orthodontic (Vivadent) and Right On (TP Orthodontics, Inc.) to have poor abrasion resistance, whereas Concise Orthodontic and Transbond (3M Unitek) had abrasion resistance comparable with restorative composites. Clinical recommendations are made based on these findings. PMID:9009926

Bearn, D R; McCabe, J F; Gordon, P H; Aird, J C

1997-01-01

231

Orthodontic movement of endodontically treated teeth: Contemporary views.  

Directory of Open Access Journals (Sweden)

Full Text Available AIM: To collect and assess the contemporary data referring to orthodontic movement of endodontically treated teeth.METHOD: Relevant original and review articles were retrieved from PubMed, Medline, Cochrane, Embase, and Scopus databases, until February 2010. RESULTS: Endodontically treated teeth can be moved equally well to vital teeth and for the same distances, without more frequent adverse consequences. They present a smaller degree of apical resorption in mean values compared to vital teeth, however this difference is not regarded to be statistically or clinically significant. Root resorption seems to be related more to the severity of trauma and the stage of root development rather than orthodontic or surgical manipulations. The obturating material of choice in the event of endodontic treatment of teeth with incomplete apex as well as in cases of teeth with complete apex under orthodontic movement, seems to be Ca(OH2, because of the evidence based action of Ca(OH2 against the frequently observed root resorption. In cases of fractures, a 12 month waiting period is suggested before the start of orthodontic treatment, while in cases with no radiographic findings treatment can begin relatively immediately. CONCLUSIONS: Orthodontic movement of endodontically treated teeth is feasible without negative consequences to the apex. Orthodontic treatment prognosis of endodontically treated teeth depends on the type, the severity and the timing of trauma, as well as the management of the case by the team of therapists.

Ioulia Ioannidou-Marathiotou

2010-01-01

232

Quadratic brackets from symplectic forms  

International Nuclear Information System (INIS)

We give a physicist oriented survey of Poisson-Lie symmetries of classical systems. We consider finite-dimensional geometric actions and the chiral WZNW model as examples for the general construction. An essential point is the appearance of quadratic Poisson brackets for group-like variables. It is believed that upon quantization they lead to quadratic exchange algebras. ((orig.))

233

Poisson brackets with prescribed Casimirs  

OpenAIRE

We consider the problem of constructing Poisson brackets on smooth manifolds $M$ with prescribed Casimir functions. If $M$ is of even dimension, we achieve our construction by considering a suitable almost symplectic structure on $M$, while, in the case where $M$ is of odd dimension, our objective is achieved by using a convenient almost cosymplectic structure. Several examples and applications are presented.

Damianou, Pantelis A.; Petalidou, Fani

2011-01-01

234

Effect of moisture, saliva, and blood contamination on the shear bond strength of brackets bonded with a conventional bonding system and self-etched bonding system  

Science.gov (United States)

Background: The success of bonding brackets to enamel with resin bonding systems is negatively affected by contamination with oral fluids such as blood and saliva. The new self-etch primer systems combine conditioning and priming agents into a single application, making the procedure more cost effective. Objective: The purpose of the study was to investigate the effect of moisture, saliva and blood contamination on shear bond strength of orthodontic brackets bonded with conventional bonding system and self-etch bonding system. Materials and Methods: Each system was examined under four enamel surface conditions (dry, water, saliva, and blood), and 80 human teeth were divided into two groups with four subgroups each of 10 according to enamel surface condition. Group 1 used conventional bonding system and Group 2 used self-etched bonding system. Subgroups 1a and 2a under dry enamel surface conditions; Subgroups 1b and 2b under moist enamel surface condition; Subgroups 3a and 3b under saliva enamel surface condition and Subgroup 4a and 4b under blood enamel surface condition. Brackets were bonded, and all the samples were then submitted to a shear bond test with a universal testing machine with a cross head speed of 1mm/sec. Results: The results showed that the contamination reduced the shear bond strength of all groups. In self-etch bonding system water and saliva had significantly higher bond strength when compared to other groups. Conclusion: It was concluded that the blood contamination showed lowest bond strength from both bonding systems. Self-etch bonding system resulted in higher bond strength than conventional bonding system under all conditions except the dry enamel surface. PMID:24678210

Prasad, Mandava; Mohamed, Shamil; Nayak, Krishna; Shetty, Sharath Kumar; Talapaneni, Ashok Kumar

2014-01-01

235

A Recursive Approach to the Kauffman Bracket  

Directory of Open Access Journals (Sweden)

Full Text Available We introduce a simple recursive relation and give an explicit formula of the Kauffman bracket of two-strand braid link . Then, we give general formulas of the bracket of the sequence of links of three-strand braids . Finally, we give an interesting result that the Kauffman bracket of the three-strand braid link is actually the product of the brackets of the two-strand braid links and . Moreover, a recursive relation for is also given.

Abdul Rauf Nizami

2014-10-01

236

Supersymmetry and the Odd Poisson Bracket  

OpenAIRE

Some applications of the odd Poisson bracket developed by Kharkov's theorists are represented, including the reformulation of classical Hamiltonian dynamics, the description of hydrodynamics as a Hamilton system by means of the odd bracket and the dynamics formulation with the Grassmann-odd Lagrangian. Quantum representations of the odd bracket are also constructed and applied for the quantization of classical systems based on the odd bracket and for the realization of the i...

Soroka, Vyacheslav A.

2002-01-01

237

Branes, Strings, and Odd Quantum Nambu Brackets  

OpenAIRE

The dynamics of topological open branes is controlled by Nambu Brackets. Thus, they might be quantized through the consistent quantization of the underlying Nambu brackets, including odd ones: these are reachable systematically from even brackets, whose more tractable properties have been detailed before.

Curtright, T. L.; Zachos, C. K.

2003-01-01

238

Branes, strings, and odd quantum Nambu brackets.  

Energy Technology Data Exchange (ETDEWEB)

The dynamics of topological open branes is controlled by Nambu Brackets. Thus, they might be quantized through the consistent quantization of the underlying Nambu brackets, including odd ones: these are reachable systematically from even brackets, whose more tractable properties have been detailed before.

Curtright, T. L.; Zachos, C. K.; High Energy Physics; Univ. Miami

2004-10-01

239

How to ... debond Clarity brackets with ease.  

Science.gov (United States)

Debonding ceramic brackets has been difficult due to problems with enamel fractures, enamel tears and patient discomfort. New brackets have weaker bases and the debonding technique has changed, with a recommendation that a pair of Mathieu needle holding pliers is used with Clarity brackets. PMID:16333049

Lee, R T

2005-12-01

240

Relationship between self-concept and satisfaction with tooth alignment and demand for orthodontic treatment and professionally determined orthodontic needs  

Directory of Open Access Journals (Sweden)

Full Text Available AbstractIntroduction: Recognition of psychological factors plays an important role in determination of orthodontic treatment needs as well as achieving a successful treatment. The aim of this study was to investigate the relationship between self-concept, dentofacial body image, subjective orthodontic treatment needs and professionally determined needs for orthodontic treatment among a group of university students.Materials and Methods: In this cross-sectional study, 164 students of Isfahan Faculty of Nursing and Midwifery were studied based on a simple sampling procedure. Data were collected using a standardized questionnaire consisting of 40 questions, including 3 parts for measurement of self-concept, dentofacial body image and self-perceived treatment need. Professionally determined orthodontic need was assessed using IOTN by two orthodontists. Data was analyzed using SPSS 11. Statistical methods for standardization of questionnaire, Cronbach's alpha, Student’s t-test and Spearman’s correlation were used at a significance level of 0.05.Results: Statistically significant correlations were seen between participants' self-concept, dentofacial body image, subjective orthodontic need and the professionally determined orthodontic need, with Spearman’s correlation coefficients of -0.16, 0.19 and -0.036, respectively (p value < 0.05.Conclusion: The majority of the students were satisfied with their teeth alignment and the more satisfied they were, the higher self-concept they had, with lower demand for orthodontic treatment. Moreover, the orthodontic needs determined by orthodontists were less among students with high self-concept. Key words: Health services needs and demand, Malocclusion, Self-assessment, Self-concept.

Amirreza Amnaie

2012-01-01

241

A força de atrito em braquetes plásticos e de aço inoxidável com a utilização de quatro diferentes tipos de amarração / Frictional forces in stainless steel and plastic brackets using four types of wire ligation  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: a finalidade deste estudo in vitro foi avaliar e comparar a resistência friccional em braquetes de aço inoxidável e de policarbonato compósito amarrados com fio metálico e elastômeros. MÉTODOS: foram utilizados quatro braquetes de aço inoxidável e quatro de policarbonato compósito (PC) par [...] a pré-molares levados à máquina universal de ensaio mecânico para a tração de um segmento de fio de aço inoxidável 0,019" x 0,025" na velocidade de 0,5mm/min, com 8mm de deslocamento total. A forma de amarração variou entre as seguintes possibilidades: amarração metálica com pinça de Steiner, metálica com pinça Mathieu, elastômero da marca Morelli e elastômero da marca TP Orthodontics. RESULTADOS E CONCLUSÕES: os módulos elastoméricos geraram mais atrito do que os metálicos e a amarração com pinça Mathieu provocou menor atrito quando comparada a todas as situações avaliadas. Os braquetes de PC geraram menor atrito do que os metálicos, porém, na escolha do material a ser utilizado na clínica, outras variáveis - tais como a resistência ao cisalhamento e à fratura, a estabilidade de cor e a aderência por microrganismos - devem ser consideradas. Abstract in english OBJECTIVE: This in vitro study evaluated and compared the frictional resistance of stainless steel and polycarbonate (PC) composite brackets tied with metal wire and elastomeric ligation. METHODS: Four stainless steel and four polycarbonate composite brackets for premolars were placed in a universal [...] testing machine for the traction of a piece of 0.019 x 0.025-in wire at 0.5 mm/min and total displacement of 8 mm. Ligations were performed according to the following alternatives: metal ligation with Steiner tying pliers; metal ligation using Mathieu tying pliers; Morelli™ elastomeric ligation; and TP Orthodontics™ elastomeric ligation. RESULTS AND CONCLUSIONS: Elastomeric modules generated more friction than the metal ligations, and the ligation with the Mathieu tying pliers caused less friction than all the other conditions under study. PC brackets generated less friction than metal brackets, but the choice of material to be used in clinical conditions should take into consideration other variables, such as resistance to shearing and to fractures, as well as color stability and microorganism adherence.

Vanessa Nínia Correia, Lima; Maria Elisa Rodrigues, Coimbra; Carla D' Agostini, Derech; Antônio Carlos de Oliveira, Ruellas.

2010-04-01

242

A força de atrito em braquetes plásticos e de aço inoxidável com a utilização de quatro diferentes tipos de amarração Frictional forces in stainless steel and plastic brackets using four types of wire ligation  

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: a finalidade deste estudo in vitro foi avaliar e comparar a resistência friccional em braquetes de aço inoxidável e de policarbonato compósito amarrados com fio metálico e elastômeros. MÉTODOS: foram utilizados quatro braquetes de aço inoxidável e quatro de policarbonato compósito (PC para pré-molares levados à máquina universal de ensaio mecânico para a tração de um segmento de fio de aço inoxidável 0,019" x 0,025" na velocidade de 0,5mm/min, com 8mm de deslocamento total. A forma de amarração variou entre as seguintes possibilidades: amarração metálica com pinça de Steiner, metálica com pinça Mathieu, elastômero da marca Morelli e elastômero da marca TP Orthodontics. RESULTADOS E CONCLUSÕES: os módulos elastoméricos geraram mais atrito do que os metálicos e a amarração com pinça Mathieu provocou menor atrito quando comparada a todas as situações avaliadas. Os braquetes de PC geraram menor atrito do que os metálicos, porém, na escolha do material a ser utilizado na clínica, outras variáveis - tais como a resistência ao cisalhamento e à fratura, a estabilidade de cor e a aderência por microrganismos - devem ser consideradas.OBJECTIVE: This in vitro study evaluated and compared the frictional resistance of stainless steel and polycarbonate (PC composite brackets tied with metal wire and elastomeric ligation. METHODS: Four stainless steel and four polycarbonate composite brackets for premolars were placed in a universal testing machine for the traction of a piece of 0.019 x 0.025-in wire at 0.5 mm/min and total displacement of 8 mm. Ligations were performed according to the following alternatives: metal ligation with Steiner tying pliers; metal ligation using Mathieu tying pliers; Morelli™ elastomeric ligation; and TP Orthodontics™ elastomeric ligation. RESULTS AND CONCLUSIONS: Elastomeric modules generated more friction than the metal ligations, and the ligation with the Mathieu tying pliers caused less friction than all the other conditions under study. PC brackets generated less friction than metal brackets, but the choice of material to be used in clinical conditions should take into consideration other variables, such as resistance to shearing and to fractures, as well as color stability and microorganism adherence.

Vanessa Nínia Correia Lima

2010-04-01

243

Orthodontic treatment and referral patterns: A survey of pediatric dentists, general practitioners, and orthodontists  

Science.gov (United States)

Objective This study aims to assess the orthodontic diagnostic skills, referral patterns, and the perceptions of orthodontic benefits of pediatric and general dentists in comparison with orthodontists. Materials and methods Two online surveys were e-mailed to pediatric dentists, general dentistry practitioners, and orthodontists registered as members of the Saudi Dental Society and the Saudi Orthodontic Society. The surveys included questions about the type of orthodontic treatment provided, referral trends, and timing; presumed benefits associated with successful orthodontic treatment; and diagnosis and treatment plans of seven cases representing different malocclusions. Results In total, 25 orthodontists, 18 pediatric dentists, and 14 general practitioners completed the survey. Only 38.8% of pediatric dentists and 7.1% of general practitioners reported that they practiced orthodontics clinically. The perceptions of the three groups toward the benefits of orthodontic treatment were comparable in the psychosocial areas. However, the orthodontists perceived significantly lesser effects of orthodontic treatment on the amelioration of temporomandibular disorder (TMD) symptoms. Pediatric dentists tended to rate the need and urgency of treatment higher, while general practitioners tended to rate the need of treatment lower. The selected treatment plans for three early malocclusion cases showed the greatest discrepancies between the orthodontists and the other two groups. Conclusions The orthodontists consistently and significantly downplayed the perceived benefit of orthodontic treatment to reduce TMD symptoms. Also, while there was a similarity in the diagnosis, there were notable differences in the proposed treatment approaches, perceived treatment need, and timing of intervention between the three groups of practitioners. PMID:25544812

Aldrees, Abdullah M.; Tashkandi, Nada E.; AlWanis, Areej A.; AlSanouni, Munerah S.; Al-Hamlan, Nasir H.

2014-01-01

244

Interrelationships of endodontic- orthodontic treatments  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this article was reviewing the literature related to the mutual effects of endodontics and orthodontics on each other providing documented information that can be used by dentists in clinical practice. The effect of orthodontic treatment on the dental pulp and its role in root resorption, the influence of previous trauma to the tooth and endodontic treatment in orthodontic tooth movements and root resorption, recommendations regarding endodontic treatment during orthodontic tooth movement and the role of the orthodontic forces in provision and outcome of endodontic treatment are being discussed. The effect of the orthodontic tooth movement on the pulp is focused primarily on the neurovascular system which can cause degenerative and/or inflammatory responses in the dental pulp. Although, most of these changes are considered reversible, it seems that teeth with complete apical foramen and teeth subjected to previous insults, such as trauma, caries, restorations and periodontal diseases are more susceptible to pulpal irreversible changes. Teeth with root canal treatment that are well cleaned shaped, and three- dimensionally obturated, exhibit less propensity to apical root resorption during orthodontic tooth movement. This outcome depends on the absence of microleakage for bacterial ingress. A traumatized tooth can be moved orthodontically with minimal risk of resorption, provided that the pulp has not been severely injured (infection or necrosis. If there is evidence of pulpal demise, appropriate endodontic treatment is necessary prior to orthodontic treatment .If a previously traumatized tooth exhibits resorption, there is a greater chance that orthodontic tooth movement will enhance the resorptive process. If a tooth has been severely traumatized (intrusion, avulsion there would be a greater incidence of resorption with tooth movement. It is recommended that teeth requiring root canal treatment during orthodontic movement be initially cleaned and shaped followed by the interim placement of calcium hydroxide. Final canal obturation with gutta-percha should be accomplished upon the completion of orthodontic treatment. Endodontically treated teeth can be moved orthodontically similar to teeth with vital pulps. In case of endodontic procedures like apexification, there may be no need to delay the orthodontic treatment.

Khedmat S

2005-05-01

245

Supersymmetry and the Odd Poisson Bracket  

CERN Document Server

Some applications of the odd Poisson bracket developed by Kharkov's theorists are represented, including the reformulation of classical Hamiltonian dynamics, the description of hydrodynamics as a Hamilton system by means of the odd bracket and the dynamics formulation with the Grassmann-odd Lagrangian. Quantum representations of the odd bracket are also constructed and applied for the quantization of classical systems based on the odd bracket and for the realization of the idea of a composite spinor structure of space-time. At last, the linear odd bracket, corresponding to a semi-simple Lie group, is introduced on the Grassmann algebra.

Soroka, V A

2001-01-01

246

Blood contamination effect on shear bond strength of an orthodontic hydrophilic resin  

OpenAIRE

OBJECTIVE: The aim of this study was to assess the impact of blood contamination on shear bond strength (SBS) and bond failure pattern of metallic brackets bonded using a new hydrophilic resin. MATERIAL AND METHODS: Eighty human premolars were randomly allocated into 4 groups (n=20) according to the bonding material and contamination pattern. GI: brackets bonded with the Transbond XT conventional system without contamination; GII: brackets bonded with the Transbond XT conventional system with...

Taís de Morais Alves da Cunha; Bruna Ariela Behrens; Denise Nascimento; Luciana Borges Retamoso; Luís Filipe Siu Lon; Orlando Tanaka; Odilon Guariza Filho

2012-01-01

247

[White spot lesions and orthodontic treatment. Prevention and treatment].  

Science.gov (United States)

Decalcification of the enamel surface adjacent to fixed orthodontic appliances, in the form of white spot lesions, is a common and frequent well-known side-effect of orthodontic treatment. Fixed appliances and the bonding materials increase the retention of biofilm and encourage the formation of white spot lesions. Management of these lesions begins with a good oral hygiene regime and needs to be associated with use of fluoride agents (fluoridated toothpaste, fluoride containing mouth rinse, gel, varnish, bonding materials, elastic ligature), CPP-ACP, antiseptics, LASER, tooth whitening, resin infiltration, micro-abrasion. The purpose of this review is to access the direct evidence regarding the prevention and management of white spot lesions during and after orthodontic treatment. PMID:25158746

Morrier, Jean-Jacques

2014-09-01

248

Temporary Anchorage Devices in Orthodontics  

Directory of Open Access Journals (Sweden)

Full Text Available Anchorage control is one of the main aspects of orthodontic treatment plan. A good appliance system should put minimum taxation of anchorage on the anchor units. The structures present with in the confinement of oral cavity are very less in number. In such cases the anchor unit gets its reinforcement from extraoral structures or intraoral appliances. Extraoral anchorages have their inherent drawbacks and most of them rely on patient cooperation. The use of implants in orthodontics to reinforce the anchorage is a recent concept. The purpose of this article is to review the implants in the context of orthodontics which are called as TAD- temporary anchorage devices.

Gowri Sankar Singaraju

2009-07-01

249

[Different orthodontic anchorage systems. A critical examination].  

Science.gov (United States)

Every orthodontic measure requires a detailed analysis of the individual anchorage situation in order to absorb (stationary anchorage) or control (reciprocal anchorage) the reactive forces and moments. Basically, an anchorage is oriented to the quality of the biological anchorage of the teeth. This is influenced by a number of factors: size of root surface, attachment level, density and structure of alveolar bone, periodontal reactivity, muscular activity, occlusal forces, craniofacial morphology and the nature of the tooth movement resulting from the planned correction. The quality of the biological anchorage may be enhanced by selective modification of the position of the anchor teeth: cortical anchorage of the first molar (Ricketts), distal inclination of the molars (Tweed, Begg) and differential torque control (Burstone). In this context, undesired anchorage effects also need to be discussed, for example interaction between the teeth being corrected and compact bone structures (symphysis menti, floor of the maxillary sinus) or the loss of anchorage by periodontal hyalinization or excessive friction within the bracket slot. In addition, the anchorage situation of ankylosed teeth and endosseous implants, as well as the advantages and disadvantages of additional mechanical anchorage aids (head-gear, Nance holding arch, lingual arch) are discussed. On the basis of the complexity of the individual biological and biomechanical aspects, guidelines are derived with which to establish anchorage control matched to the specific situation. PMID:8375786

Diedrich, P

1993-08-01

250

Exterior differentials in superspace and Poisson brackets  

Science.gov (United States)

It is shown that two definitions for an exterior differential in superspace, giving the same exterior calculus, yet lead to different results when applied to the Poisson bracket. A prescription for the transition with the help of these exterior differentials from the given Poisson bracket of definite Grassmann parity to another bracket is introduced. It is also indicated that the resulting bracket leads to generalization of the Schouten-Nijenhuis bracket for the cases of superspace and brackets of diverse Grassmann parities. It is shown that in the case of the Grassmann-odd exterior differential the resulting bracket is the bracket given on exterior forms. The above-mentioned transition with the use of the odd exterior differential applied to the linear even/odd Poisson brackets, that correspond to semi-simple Lie groups, results, respectively, in also linear odd/even brackets which are naturally connected with the Lie superalgebra. The latter contains the BRST and anti-BRST charges and can be used for calculation of the BRST operator cogomology.

Soroka, Dmitrij V.; Soroka, Vyacheslav A.

2003-03-01

251

Exterior differentials in superspace and Poisson brackets  

International Nuclear Information System (INIS)

It is shown that two definitions for an exterior differential in superspace, giving the same exterior calculus, yet lead to different results when applied to the Poisson bracket. A prescription for the transition with the help of these exterior differentials from the given Poisson bracket of definite Grassmann parity to another bracket is introduced. It is also indicated that the resulting bracket leads to generalization of the Schouten-Nijenhuis bracket for the cases of superspace and brackets of diverse Grassmann parities. It is shown that in the case of the Grassmann-odd exterior differential the resulting bracket is the bracket given on exterior forms. The above-mentioned transition with the use of the odd exterior differential applied to the linear even/odd Poisson brackets, that correspond to semi-simple Lie groups, results, respectively, in also linear odd/even brackets which are naturally connected with the Lie superalgebra. The latter contains the BRST and anti-BRST charges and can be used for calculation of the BRST operator cogomology. (author)

252

Exterior Differentials in Superspace and Poisson Brackets  

CERN Document Server

It is shown that two definitions for an exterior differential in superspace, giving the same exterior calculus, yet lead to different results when applied to the Poisson bracket. A prescription for the transition with the help of these exterior differentials from the given Poisson bracket of definite Grassmann parity to another bracket is introduced. It is also indicated that the resulting bracket leads to generalisation of the Schouten-Nijenhuis bracket for the cases of superspace and brackets of diverse Grassmann parities. It is shown that in the case of the Grassmann-odd exterior differential the resulting bracket is the bracket given on exterior forms. The above-mentioned transition with the use of the odd exterior differential applied to the linear even/odd Poisson brackets, that correspond to semi-simple Lie groups, results, respectively, in also linear odd/even brackets which are naturally connected with the Lie superalgebra. The latter contains the BRST and anti-BRST charges and can be used for calcul...

Soroka, D V; Soroka, Dmitrij V.; Soroka, Vyacheslav A.

2003-01-01

253

A Comparison of Apical Root Resorption in Incisors after Fixed Orthodontic Treatment with Standard Edgewise and Straight Wire (MBT) Method  

OpenAIRE

Statement of Problem: One of the major outcomes of orthodontic treatment is the apical root resorption of teeth moved during the treatment. Identifying the possible risk factors, are necessary for every orthodontist. Purpose: The aim of this study was to compare the rate of apical root resorption after fixed orthodontic treatment with standard edgewise and straight wire (MBT) method, and also to evaluate other factors effecting the rate of root resorption in orthodontic treatments.Materials a...

Sm, Zahed Zahedani; Oshagh M; Momeni Danaei Sh.; Smm, Roeinpeikar

2013-01-01

254

Influence of in vitro pigmenting of esthetic orthodontic ligatures on smile attractiveness  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: To evaluate the perception of dental students and orthodontists on the degree of influence that pigmented esthetic elastic ligatures have on smile attractiveness, by judging clinical photographs. METHODS: Sixteen clinical facial photographs of the smile and 16 close up images of the smile of a single patient wearing monocrystalline porcelain orthodontic brackets, Teflon coated NiTi wire brackets and esthetic elastic ligatures of five different commercial brands were distributed into eight groups, G1 to G8 (Morelli®, Ortho Tecnology™, TP Orthodontics™, Unitek/3M™clear, Unitek/3M™ obscure, American Orthodontics™ clear, American Orthodontics™ pearl and American Orthodontics™ metallic pearl. Twenty ligatures were used in each group, totaling 160 ligatures. Half of them were used in their natural state, and the other half after in vitro pigmentation. All the photographs were judged by 40 evaluators, 20 orthodontists and 20 dental students. RESULTS: For orthodontists, American™ pearl (G7 ligatures were those that least influenced the degree of attractiveness of the smile in the two types of photographs used. For the dental students, in the facial photographs of the smile, ligatures with the best performance were Morelli® (G1, American™ clear (G6 and American™ pearl (G7 and in the close up photographs of the smile, American™ pearl, metallic pearl and clear (G7, G8 and G6. CONCLUSIONS: For both orthodontists and dental students, pigmentation of the elastic ligatures had a negative influence on the degree of attractiveness of smiles in the two types of clinical photographs evaluated.OBJETIVO: avaliar, através de fotografias clínicas, entre estudantes de Odontologia e ortodontistas, o grau de influência que ligaduras elásticas estéticas pigmentadas exercem sobre a atratividade do sorriso. MÉTODOS: foram utilizadas 16 fotografias clínicas faciais do sorriso e 16 de sorriso aproximado de um único paciente portando braquetes ortodônticos de porcelana monocristalina, fio de NiTi teflonado e ligaduras elásticas estéticas de cinco marcas comerciais diferentes, distribuídas em oito grupos, G1 a G8 (Morelli, Ortho Technology, TP Orthodontics, 3M/Unitek clear, 3M/Unitek obscure, American Orthodontics clear, American Orthodontics pearl e American Orthodontics metalic pearl. Foram utilizadas 20 ligaduras de cada grupo, totalizando 160 ligaduras. Metade delas foi utilizada em estado natural e a outra metade após pigmentação in vitro. Todas as fotografias foram julgadas por 40 avaliadores, sendo 20 ortodontistas e 20 estudantes de Odontologia. RESULTADOS: para ortodontistas, as ligaduras American Orthodontics pearl (G7 foram as que menos influenciaram o grau de atratividade do sorriso nos dois tipos de fotografias utilizadas. Para os estudantes de Odontologia, nas fotografias faciais do sorriso, as que obtiveram o melhor desempenho foram Morelli (G1, American Orthodontics clear (G6 e American Orthodontics pearl (G7 e, nas fotografias de sorriso aproximado, American Orthodontics pearl, metalic pearl e clear (G7, G8 e G6, respectivamente. CONCLUSÕES: tanto para ortodontistas quanto para estudantes de Odontologia, a pigmentação das ligaduras elásticas influenciou de forma negativa o grau de atratividade dos sorrisos nos dois tipos de fotografias clínicas avaliadas.

Camila Ferraz

2012-10-01

255

Influence of in vitro pigmenting of esthetic orthodontic ligatures on smile attractiveness  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: avaliar, através de fotografias clínicas, entre estudantes de Odontologia e ortodontistas, o grau de influência que ligaduras elásticas estéticas pigmentadas exercem sobre a atratividade do sorriso. MÉTODOS: foram utilizadas 16 fotografias clínicas faciais do sorriso e 16 de sorriso aproxi [...] mado de um único paciente portando braquetes ortodônticos de porcelana monocristalina, fio de NiTi teflonado e ligaduras elásticas estéticas de cinco marcas comerciais diferentes, distribuídas em oito grupos, G1 a G8 (Morelli, Ortho Technology, TP Orthodontics, 3M/Unitek clear, 3M/Unitek obscure, American Orthodontics clear, American Orthodontics pearl e American Orthodontics metalic pearl). Foram utilizadas 20 ligaduras de cada grupo, totalizando 160 ligaduras. Metade delas foi utilizada em estado natural e a outra metade após pigmentação in vitro. Todas as fotografias foram julgadas por 40 avaliadores, sendo 20 ortodontistas e 20 estudantes de Odontologia. RESULTADOS: para ortodontistas, as ligaduras American Orthodontics pearl (G7) foram as que menos influenciaram o grau de atratividade do sorriso nos dois tipos de fotografias utilizadas. Para os estudantes de Odontologia, nas fotografias faciais do sorriso, as que obtiveram o melhor desempenho foram Morelli (G1), American Orthodontics clear (G6) e American Orthodontics pearl (G7) e, nas fotografias de sorriso aproximado, American Orthodontics pearl, metalic pearl e clear (G7, G8 e G6, respectivamente). CONCLUSÕES: tanto para ortodontistas quanto para estudantes de Odontologia, a pigmentação das ligaduras elásticas influenciou de forma negativa o grau de atratividade dos sorrisos nos dois tipos de fotografias clínicas avaliadas. Abstract in english OBJECTIVE: To evaluate the perception of dental students and orthodontists on the degree of influence that pigmented esthetic elastic ligatures have on smile attractiveness, by judging clinical photographs. METHODS: Sixteen clinical facial photographs of the smile and 16 close up images of the smile [...] of a single patient wearing monocrystalline porcelain orthodontic brackets, Teflon coated NiTi wire brackets and esthetic elastic ligatures of five different commercial brands were distributed into eight groups, G1 to G8 (Morelli®, Ortho Tecnology™, TP Orthodontics™, Unitek/3M™clear, Unitek/3M™ obscure, American Orthodontics™ clear, American Orthodontics™ pearl and American Orthodontics™ metallic pearl). Twenty ligatures were used in each group, totaling 160 ligatures. Half of them were used in their natural state, and the other half after in vitro pigmentation. All the photographs were judged by 40 evaluators, 20 orthodontists and 20 dental students. RESULTS: For orthodontists, American™ pearl (G7) ligatures were those that least influenced the degree of attractiveness of the smile in the two types of photographs used. For the dental students, in the facial photographs of the smile, ligatures with the best performance were Morelli® (G1), American™ clear (G6) and American™ pearl (G7) and in the close up photographs of the smile, American™ pearl, metallic pearl and clear (G7, G8 and G6). CONCLUSIONS: For both orthodontists and dental students, pigmentation of the elastic ligatures had a negative influence on the degree of attractiveness of smiles in the two types of clinical photographs evaluated.

Camila, Ferraz; Marcelo, Castellucci; Márcio, Sobral.

2012-10-01

256

Comparison between two methods for resin removing after bracket debonding  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o objetivo deste trabalho foi avaliar, por microscopia eletrônica de varredura, a eficácia de dois discos abrasivos de silicone e óxido de alumínio para a remoção da resina remanescente após a descolagem de braquetes ortodônticos. MÉTODOS: foram utilizados 10 dentes bovinos selecionados al [...] eatoriamente, sendo 2 para o grupo controle e os demais divididos em dois grupos, os quais receberam colagem de braquetes ortodônticos com resina ortodôntica Concise (3M). Os métodos de remoção da resina após a descolagem dos acessórios ortodônticos em apenas uma etapa foram: Grupo A - disco Optimize (TDV); e Grupo B - disco Onegloss (Shofu), empregados em baixa rotação. Após a remoção da resina remanescente pelos métodos mencionados, os dentes foram preparados para serem submetidos à análise em microscopia eletrônica de varredura, obtendo-se fotografias da superfície do esmalte com aumento de 50X. Seis examinadores avaliaram as fotografias seguindo a escala de avaliação de Zachrisson e Arthun (1979). RESULTADOS: no Grupo A, observou-se pequenos arranhões na superfície do esmalte, bem como pouco remanescente de resina em algumas das fotografias; enquanto, no Grupo B, observou-se maior lisura, pouco ou nenhum remanescente de resina e alguns riscos nas fotografias. Não houve diferença estatisticamente significativa entre os dois métodos avaliados e o grupo controle. CONCLUSÃO: os dois discos abrasivos mostraram-se eficientes para remoção da resina remanescente após a descolagem de braquete em única etapa. Abstract in english OBJECTIVE: The aim of this study was to assess - using scanning electron microscopy (SEM) - the effectiveness of two abrasive discs, one made from silicon and one from aluminum oxide, in removing adhesive remnants (AR) after debonding orthodontic brackets. METHODS: Ten randomly selected bovine teeth [...] were used, i.e., 2 in the control group, and the other 8 divided into two groups, which had orthodontic brackets bonded to their surface with Concise Orthodontic Adhesive (3M). The following methods were employed - in one single step - to remove AR after debracketing: Group A, Optimize discs (TDV) and Group B, Onegloss discs (Shofu), used at low speed. After removing the AR with the aforementioned methods, the teeth were prepared to undergo SEM analysis, and photographs were taken of the enamel surface with 50x magnification. Six examiners evaluated the photographs applying the Zachrisson and Årtun enamel surface index (ESI) system (1979). RESULTS: Group A exhibited minor scratches on the enamel surface as well as some AR in some of the photographs, while Group B showed a smoother surface, little or no AR and some abrasion marks in the photographs. No statistically significant differences were found between the two methods and the control group. CONCLUSIONS: The two abrasive discs were effective in removing the AR after bracket debonding in one single step.

Rodrigo De, Marchi; Luciana Manzotti De, Marchi; Raquel Sano Suga, Terada; Hélio Hissashi, Terada.

2012-12-01

257

Temporary Anchorage Devices in Orthodontics  

OpenAIRE

Anchorage control is one of the main aspects of orthodontic treatment plan. A good appliance system should put minimum taxation of anchorage on the anchor units. The structures present with in the confinement of oral cavity are very less in number. In such cases the anchor unit gets its reinforcement from extraoral structures or intraoral appliances. Extraoral anchorages have their inherent drawbacks and most of them rely on patient cooperation. The use of implants in orthodontics to reinforc...

Gowri Sankar Singaraju; Vasu Murthy

2009-01-01

258

Review of properties and clinical applications of orthodontic wires.  

Directory of Open Access Journals (Sweden)

Full Text Available During the last decades, a variety of alloys has been used in orthodontics to manufacture wires. The orthodontic clinician is called to select from a large number of materials that meet the biomechanical requirements of the clinical case to be treated. Mechanical properties of orthodontic wires are assessed by different laboratory tests, such as tensile, torsional, and bending tests. Although wire characteristics determined by such tests cannot be directly linked with their clinical application, they provide a basis for useful comparisons. The "ideal" wire characteristics have been specified by a number of authors. However, each wire may be considered ideal or not, depending on the targeted clinical outcome on each case. The clinician should know the properties and biomechanical behavior of available wires in order to choose the appropriate wire depending on the targeted outcome in different orthodontic treatment phases. The aim of this literature review is to summarize orthodontic wire properties and demonstrate their clinical applications as shown by their general properties. Stainless steel, cobalt-chromium, nickel-titanium, beta-titanium and multistranded wires are studied. Moreover, the so-called "aesthetic" wires are reviewed, as well as their potential development expected in the near future.

Ilias Mistakidis

2011-01-01

259

A Recursive Approach to the Kauffman Bracket  

OpenAIRE

We introduce a simple recursive relation and give an explicit formula of the Kauffman bracket of two-strand braid link . Then, we give general formulas of the bracket of the sequence of links of three-strand braids . Finally, we give an interesting result that the Kauffman bracket of the three-strand braid link

Abdul Rauf Nizami; Mobeen Munir; Umer Saleem; Ansa Ramzan

2014-01-01

260

Linear Odd Poisson Bracket on Grassmann Variables  

OpenAIRE

A linear odd Poisson bracket (antibracket) realized solely in terms of Grassmann variables is suggested. It is revealed that the bracket, which corresponds to a semi-simple Lie group, has at once three Grassmann-odd nilpotent $\\Delta$-like differential operators of the first, the second and the third orders with respect to Grassmann derivatives, in contrast with the canonical odd Poisson bracket having the only Grassmann-odd nilpotent differential $\\Delta$-operator of the se...

Soroka, V. A.

1998-01-01

261

Degenerate Odd Poisson Bracket on Grassmann Variables  

Science.gov (United States)

A linear degenerate odd Poisson bracket (antibracket) realized solely on Grassmann variables is presented. It is revealed that this bracket has at once three nilpotent $\\Delta$-like differential operators of the first, the second and the third orders with respect to the Grassmann derivatives. It is shown that these $\\Delta$-like operators together with the Grassmann-odd nilpotent Casimir function of this bracket form a finite-dimensional Lie superalgebra.

Soroka, V. A.

2000-05-01

262

Degenerate Odd Poisson Bracket on Grassmann Variables  

OpenAIRE

A linear degenerate odd Poisson bracket (antibracket) realized solely on Grassmann variables is presented. It is revealed that this bracket has at once three nilpotent $\\Delta$-like differential operators of the first, the second and the third orders with respect to the Grassmann derivatives. It is shown that these $\\Delta$-like operators together with the Grassmann-odd nilpotent Casimir function of this bracket form a finite-dimensional Lie superalgebra.

Soroka, V. A.

1998-01-01

263

Linear Odd Poisson Bracket on Grassmann Variables  

CERN Document Server

A linear odd Poisson bracket (antibracket) realized solely in terms of Grassmann variables is presented. It is revealed that the bracket, which corresponds to a semi-simple Lie group, has at once three Grassmann-odd nilpotent $\\Delta$-like differential operators of the first, the second and the third orders with respect to the Grassmann derivatives. It is shown that this function of this bracket form a finite-dimensional Lie superalgebra.

Soroka, V A

1999-01-01

264

Degenerate Odd Poisson Bracket on Grassmann variables  

CERN Document Server

A linear degenerate odd Poisson bracket (antibracket) realized solely on Grassmann variables is presented. It is revealed that this bracket has at once three nilpotent $\\Delta$-like differential operators of the first, the second and the third orders with respect to the Grassmann derivatives. It is shown that this $\\Delta$-like operators together with the Grassmann-odd nilpotent Casimir function of this bracket form a finite-dimensional Lie superalgebra.

Soroka, V A

2000-01-01

265

Immunosuppressants: implications in Orthodontics  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english INTRODUCTION: There are medications capable of affecting bone metabolism and the rate of tooth movement. Among these medications are the immunosuppressants, which act by repressing the action of T lymphocytes, however they can cause bone loss and consequently lead to osteoporosis. Osteoporosis is a [...] common complication following kidney, heart, liver or lung transplantation. The immunosuppressant treatment for preventing organ rejection after transplantation, in general, includes glucocorticoids, cyclosporine, tacrolimus, and sirolimus. All these drugs can have jeopardizing effects on bone mineral homeostasis and consequently influence tooth movement. In recent years, however, the increasing use of immunosuppressants has raised questions about their effects on bone metabolism in patients undergoing orthodontic treatment. OBJECTIVE: The objective of this review study was to inform orthodontists about the influence of immunosuppressants on bone metabolism and tooth movement.

Rogério Lacerda dos, Santos; Maria Cláudia Mesquita, Lacerda; Renato Torres, Gonçalves; Marco Aurélio, Martins; Margareth Maria Gomes de, Souza.

2012-04-01

266

Immunosuppressants: implications in Orthodontics  

Directory of Open Access Journals (Sweden)

Full Text Available INTRODUCTION: There are medications capable of affecting bone metabolism and the rate of tooth movement. Among these medications are the immunosuppressants, which act by repressing the action of T lymphocytes, however they can cause bone loss and consequently lead to osteoporosis. Osteoporosis is a common complication following kidney, heart, liver or lung transplantation. The immunosuppressant treatment for preventing organ rejection after transplantation, in general, includes glucocorticoids, cyclosporine, tacrolimus, and sirolimus. All these drugs can have jeopardizing effects on bone mineral homeostasis and consequently influence tooth movement. In recent years, however, the increasing use of immunosuppressants has raised questions about their effects on bone metabolism in patients undergoing orthodontic treatment. OBJECTIVE: The objective of this review study was to inform orthodontists about the influence of immunosuppressants on bone metabolism and tooth movement.

Rogério Lacerda dos Santos

2012-04-01

267

Quadratic Poisson brackets compatible with an algebra structure  

CERN Document Server

Quadratic Poisson brackets on a vector space equipped with a bilinear multiplication are studied. A notion of a bracket compatible with the multiplication is introduced and an effective criterion of such compatibility is given. Among compatible brackets, a subclass of coboundary brackets is described, and such brackets are enumerated in a number of examples.

Balinsky, A A

1994-01-01

268

Evaluation of enamel surface after bracket debonding and polishing Avaliação da superfície do esmalte dentário após a remoção do braquete e polimento  

OpenAIRE

INTRODUCTION: Preserving the dental enamel structure during removal of orthodontic accessories is a clinician's obligation. Hence the search for an evidence based debonding protocol. OBJECTIVE: to evaluate and compare, by means of scanning electron microscopy (SEM), the effects of four different protocols of bracket debonding and subsequent polishing on enamel surface, and to propose a protocol that minimizes damage to enamel surface. METHODS: Twelve bovine permanent incisors were divided int...

Lilian Maria Brisque Pignatta; Sillas Duarte Júnior; Eduardo César Almada Santos

2012-01-01

269

Your Child's First Orthodontic Check-Up  

Science.gov (United States)

... the first recognition of the existence of an orthodontic problem, but no later than age 7. By ... teeth for an orthodontist to determine whether an orthodontic problem exists or is developing. Putting off a ...

270

Orthodontics : in Africa or for Africa  

OpenAIRE

The Department of Orthodontics was founded in 1960 with an independent head of department. After 35 years it is appropriate to delineate the field of study of modern orthodontics and also to set course for the future. This inaugural address will contrast orthodontics for Africa in the context of a developing country with orthodontics in Africa in the context of a developed country. The department envisages playing an important role in training the healthcare workers who will provide commun...

Wiltshire, W. A.

1995-01-01

271

Toda brackets and congruences of modular forms  

OpenAIRE

This paper investigates the relation between Toda brackets and congruences of modular forms. It determines the $f$-invariant of Toda brackets and thereby generalizes the formulas of J.F.\\ Adams for the classical $e$-invariant to the chromatic second filtration.

Laures, Gerd

2011-01-01

272

Corrosion of weldments in orthodontic appliances  

International Nuclear Information System (INIS)

The study of corrosion-related problems of dental materials has undergone a considerable development in recent years in order to avoid the use of materials with insufficient corrosion resistance in patients mouth. The subject of the present work was to study a particular type of corrosion: galvanic corrosion. One of the most common case of galvanic couples in patients mouth are the orthodontic appliances. The materials studied in the present work were stainless steel strips and silver-copper wires, isolated and welded between them. The electrochemical tests were performed in a NaCl 0.1M and Lactic Acid 0.1 M solution (pH2.3), and after test, the specimens were observed using the optical and scanning electron microscope. The results show that when stainless steel is coupled with a silver solder, the last is the anode of the galvanic couple. As a consequence of this, the silver solder undergone a severe attack. Stainless steel orthodontic appliances with silver solder are feasibly destroyed due to a severe attack on the filler metal disjoining the welded parts. (author) 9 refs

273

The influence of fixed orthodontic appliances on masticatory and swallowing threshold performances.  

Science.gov (United States)

To test the hypothesis that treatment with orthodontic appliances disturbs masticatory and swallowing performances. Twenty-seven subjects with malocclusions requiring orthodontic treatment were included in this prospective study. The masticatory and swallowing performances were evaluated at five different times: before bracket placement (T0), immediately after archwire placement (T1), 48 h after archwire placement (T2), 30 days after archwire placement (T3) and 3 months after the initial appointment (T4). Masticatory performance was determined by the median particle sizes for the Optocal test food after 15 chewing strokes, and the swallowing thresholds were registered for both the test food and a natural food (peanuts). Pain during mastication was evaluated using a 100-mm visual analogue scale. Masticatory performance was significantly reduced at T2, at which time patients reported the highest pain values. The time spent to the first swallow was increased at T2 for the natural food but not for the test food. The values for pain, masticatory and swallowing performances at T3 and T4 were similar to those at T0. Orthodontic patient masticatory function is only reduced during the period of higher pain experience, which could also disrupt the deglutition of harder foods. However, neither mastication nor deglutition processes were disturbed by orthodontic appliances in long-term treatment. PMID:25155222

Magalhães, I B; Pereira, L J; Andrade, A S; Gouvea, D B; Gameiro, G H

2014-12-01

274

Problems in Standardization of Orthodontic Shear Bond Strength Tests; A Brief Review  

Directory of Open Access Journals (Sweden)

Full Text Available Bonding brackets to the enamel surface has gained much popularity today. New adhesive systems have been introduced and marketed and a considerable increase in research regarding bond strength has been published. A considerable amount of these studies deal with shear bond strength of adhesives designed for orthodontic purpose.Previous studies have used variety of test designs. This diversity in test design is due to the fact that there is no standard method for evaluating shear bond strength in orthodontics. Therefore comparison of data obtained from different study is almost impossible.This article tries to briefly discuss the developments occurred in the process of shear bond strength measurement of orthodontic adhesives with an emphasis on the type of test set up and load application.Although the test designs for measuring shear bond strength in orthodontics are still far from ideal, attempts must be made to standardize these tests especially in order to makecomparison of different data easier. It is recommended that test designs be set up in such a manner that better matches with the purpose of the study.

M.S. A. Akhoundi

2005-03-01

275

Asymmetric extractions in orthodontics  

Directory of Open Access Journals (Sweden)

Full Text Available INTRODUCTION: Extraction decisions are extremely important in during treatment planning. In addition to the extraction decision orthodontists have to choose what tooth should be extracted for the best solution of the problem and the esthetic/functional benefit of the patient. OBJECTIVE: This article aims at reviewing the literature relating the advantages, disadvantages and clinical implications of asymmetric extractions to orthodontics. METHODS: Keywords were selected in English and Portuguese and the EndNote 9 program was used for data base search in PubMed, Web of Science (WSc and LILACS. The selected articles were case reports, original articles and prospective or retrospective case-control studies concerning asymmetrical extractions of permanent teeth for the treatment of malocclusions. CONCLUSION: According to the literature reviewed asymmetric extractions can make some specific treatment mechanics easier. Cases finished with first permanent molars in Class II or III relationship in one or both sides seem not to cause esthetic or functional problems. However, diagnosis knowledge and mechanics control are essential for treatment success.

Camilo Aquino Melgaço

2012-04-01

276

Fricção em braquetes gerada por fios de aço inoxidável, superelásticos com IonGuard e sem IonGuard / Friction force on brackets generated by stainless steel wire and superelastic wires with and without IonGuard  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: o objetivo deste estudo foi verificar a fricção no braquete (Roth, Composite, 10.17.005, 3,2mm, largura 0,022" x 0,030", Torque -2° e angulação +13°, Morelli®, Brasil), utilizando fios ortodônticos retangulares de 0,019" x 0,025" de aço inoxidável (Morelli®, Brasil) e de níquel-titânio sup [...] erelásticos Bioforce com IonGuard e sem IonGuard (Bioforce, GAC®, EUA). MÉTODOS: foram utilizados 24 conjuntos braquetes/segmento de fio, divididos em 3 grupos de acordo com o fio. Cada conjunto braquete/segmento de fio foi testado 3 vezes e obtida uma média. Os ensaios foram realizados em máquina universal de ensaios EMIC DL2000®. Os dados foram submetidos à Análise de Variância com significância de 95%. RESULTADOS: o fio retangular Bioforce com IonGuard apresentou fricção significativamente menor que o Bioforce sem IonGuard, porém sem diferença do fio de aço inoxidável. Entretanto, o coeficiente de variação dos fios Bioforce com e sem IonGuard foi menor que o do fio de aço inoxidável. CONCLUSÃO: os fios retangulares de 0,019" x 0,025" Bioforce com IonGuard apresentam menor fricção que o fio Bioforce sem IonGuard, sem diferença para o fio de aço inoxidável. Abstract in english OBJECTIVE: The aim of this study was to evaluate the friction forces on brackets (Roth, Composite, 10.17.005, 3.2 mm, width 0.022" x 0.030 ", Torque -2° and angulation +13°, Morelli®, Brazil), with stainless steel orthodontic rectangular wire (Morelli®, Brazil) and nickel titanium superelastic Biofo [...] rce wires with and without IonGuard (Bioforce, GAC®, USA). MATERIAL AND METHODS: Twenty-four brackets/wire segment combinations were used, distributed into three groups according to the orthodontic wire. Each bracket/wire segment combination was tested three times. The tests were performed in a universal testing machine Emic DL2000®. The data was submitted to ANOVA one way followed by Tukey's post hoc test (p

Luiz Carlos Campos, Braga; Mario, Vedovello Filho; Mayury, Kuramae; Heloísa Cristina, Valdrighi; Sílvia Amélia Scudeler, Vedovello; Américo Bortolazzo, Correr.

2011-08-01

277

Effect of fixed orthodontic appliances on salivary microbial parameters at 6 months: a controlled observational study  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Objective: The aim of this study was to assess the microbial changes in children with fixed orthodontic appliances compared with a control group of children without orthodontic treatment. Material and Methods: Ninety-five children, aged between 12 and 16 years, participated in this study. Fort [...] y-eight subjects were fitted with fixed orthodontic appliances and forty-seven were free of any such appliances. The follow-up was 6 months for all children. The association between orthodontic appliances and high levels of Streptococcus mutans and Lactobacillus spp was assessed with logistic regression models, taking age, sex, pH and buffer capacity into account. Results: Differences at baseline between the two groups were not statistically significant. We found that wearing a fixed orthodontic appliance was associated with high levels of Streptococcus mutans and Lactobacillus spp (adjusted OR: 6.65, 95% CI [1.98-22.37]; 9.49, 95% CI [2.57-35.07], respectively), independently of other variables. Conclusion: The originality of the present epidemiological study was to evaluate the evolution of salivary microbial parameters in a population of children with fixed orthodontic appliances. Our results show an increase of Streptococcus mutans and Lactobacillus spp values during the follow-up. The whole dental workforce should be aware that preventive measures are of paramount importance during orthodontic treatment.

Delphine, MARET; Christine, MARCHAL-SIXOU; Jean-Noel, VERGNES; Olivier, HAMEL; Marie, GEORGELIN-GURGEL; Lucas, VAN DER SLUIS; Michel, SIXOU.

2014-01-01

278

Effects of different chlorhexidine pretreatments on adhesion of metal brackets in vitro  

OpenAIRE

Abstract Objective To investigate the effect of chlorhexidine applications in various forms and concentrations on adhesion and failure modes of metal brackets in vitro. Material and methods Ninety bovine enamel specimens were allocated to six groups (n=15). Metal brackets were bonded on all specimens after chlorhexidine pre-treatments forming the following groups: (1) untreated specimens (control); (2) 40% varnish (EC40, Biodent BV, Netherlands), remnan...

Frey Corinne; Yetkiner Enver; Stawarczyk Bogna; Attin Thomas; Attin Rengin

2012-01-01

279

Heat Exchanger Support Bracket Design Calculations  

Energy Technology Data Exchange (ETDEWEB)

This engineering note documents the design of the heat exchanger support brackets. The heat exchanger is roughly 40 feet long, 22 inches in diameter and weighs 6750 pounds. It will be mounted on two identical support brackets that are anchored to a concrete wall. The design calculations were done for one bracket supporting the full weight of the heat exchanger, rounded up to 6800 pounds. The design follows the American Institute of Steel Construction (AISC) Manual of steel construction, Eighth edition. All calculated stresses and loads on welds were below allowables.

Rucinski, Russ; /Fermilab

1995-01-12

280

Longitudinal tibial epiphyseal bracket in Nievergelt syndrome  

Energy Technology Data Exchange (ETDEWEB)

A patient is described with lower extremity mesomelic dwarfism associated with bilateral congenital elbow, hip, and knee dislocations. Rhomboid-shaped tibiae and delayed ossification of the primary fibular ossification centers were demonstrated at birth. Plain films and magnetic resonance imaging revealed that the tibial deformities were due to the presence of longitudinal epiphyseal brackets. These brackets were observed at surgery and confirmed histologically. Recognition of the longitudinal epiphyseal bracket and its relationship to the tibial deformities seen in this patient with Nievergelt syndrome is important for planning surgical treatment. (orig.).

Burnstein, M.I.; De Smet, A.A.; Breed, A.L.; Thomas, J.R.; Hafez, G.R.

1989-04-01

281

A critical review of older and contemporary applications of biomechanical methods in orthodontics.  

OpenAIRE

This paper attempts a review of the literature related to the applications and conclusions of methods of theoretical and applied mechanics, experimental strength of materials as well as contemporary computerized methods used in Orthodontics. These methods are evaluated based on contemporary data from both scientific fields, i.e. Mechanics and Orthodontics. Special reference and discussion is made concerning the finite element method which seems to be the best of all. There is also a brief ref...

Provatidis, Ch G.; Toutountzakis, N. E.

1998-01-01

282

Effect of Tramadol (?-opioid receptor agonist) on orthodontic tooth movements in a rat model  

OpenAIRE

Objective: Tramadol is a synthetic analgesic of opioids which has more flexible mechanisms of action than typical opioids. Since it has been reported in previous study that typical opioids like morphine can affect the bone homeostasis, it is worthwhile to examine the effects of tramadol on tooth movement. In this study we investigated effects of tramadol on orthodontic tooth movement in rats.Materials and Methods: 30 male wistar rats were selected and received orthodontic appliance. 3 groups ...

Javadi, E.; Alaeddini, M.; Ar, Dehpour; Ahmad Akhoundi, M. S.; Noroozi, H.; Rashidpour, M.

2012-01-01

283

Effect of dental bleaching after bracket bonding and debonding using three different adhesive systems  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o objetivo desse estudo foi avaliar a influência da colagem e descolagem de braquetes ortodônticos no clareamento caseiro, considerando três diferentes sistemas adesivos. MÉTODOS: quarenta e quatro incisivos bovinos foram divididos em quatro grupos, de acordo com o sistema adesivo utilizad [...] o para colagem dos braquetes. Após a descolagem dos braquetes, os dentes foram pigmentados por 96 horas e depois clareados com peróxido de carbamida a 10% por 6 horas diárias, durante duas semanas. Foram realizadas fotografias digitais padronizadas nos tempos: T0 (inicial); T1 (após descolagem); T2 (após pigmentação); T3, T4 e T5 representando 1, 7 e 14 dias de clareamento. Testes de repetitividade e de estabilidade foram realizados para avaliar a acurácia do método. As imagens foram avaliadas pelo software Adobe Photoshop 7.0, considerando os parâmetros de cor (L*a*b*) e a diferença total de cor adaptada para esse estudo (?;E'). RESULTADOS: os resultados do presente estudo (ANOVA e Tukey; p Abstract in english OBJECTIVE: To evaluate the influence of bonding and debonding of orthodontic brackets on dental in-home bleaching, taking into account three different adhesive systems. METHODS: Forty-four bovine incisors were divided into four groups according to the primer system used for orthodontic bracket bondi [...] ng. Following the debonding of orthodontic brackets, the teeth were stored in staining solution for 96 hours. Then, teeth were whitened using 10% carbamide peroxide for two weeks at a 6-hour-a-day regime. Standardized digital photographs were taken at the following intervals: T0 (initial); T1 (after debonding); T2 (after pigmentation); T3, T4 and T5 representing 1, 7, and 14 days of bleaching. Repeatability and stability tests were carried out to check the method accuracy. Images were analyzed using Adobe Photoshop 7.0 software considering (L*a*b*)color coordinate values and a modified color difference total (?;E'). RESULTS: The results of this study (ANOVA and Tukey; p

Lucianna de Oliveira, Gomes; Paula, Mathias; Patricia, Rizzo; Telma Martins de, Araújo; Maria Cristina Teixeira, Cangussu.

2013-04-01

284

Orthodontic Research Output from Iran in International and National Journals  

Science.gov (United States)

Objective: The number of scientific papers is a conventional metric to measure a country’s research performance in a particular area. The aim of this survey was to demonstrate statistical information about orthodontic research published in international and national journals. Materials and Methods: Pubmed as an international and IranMedex and SID as national databases were searched between1997 and 2012. The keyword searching method was used in English and Persian. Abstracts were reviewed and unrelated articles were omitted. Data were obtained and transferred to Microsoft Excel to survey the scintometric indicators. Results: According to the defined criteria, a total of 733 papers were found showing a considerable increase. Five hundred papers (68.2%) were published in domestic journals, and 233 (31.8%) were published in PubMed indexed journals. Most of the orthodontic articles originated from Shahid Beheshti University of Medical Sciences (22.9%). The Journal of Dental School, Shahid Beheshti University of Medical Sciences published most of the national papers (27.8%) and the Australian Orthodontic Journal published the majority of international papers (9.9%) In terms of study design, 52.5% of the articles were observational and 39.4% were interventional. Conclusion: Orthodontic research production in Iran has made significant strides in the recent years and researchers should focus on the quality of the study in this field in order to apply research production in evidence base dentistry. PMID:24910678

Badri, Samareh; Akhoundi, Mohammad Sadegh Ahmad; Fard, Mohammad JavadKharrazi; Momeni, Nafiseh; Hedayati, Zohreh; Vakili, Vajihe

2014-01-01

285

Learning styles of orthodontic residents.  

Science.gov (United States)

Significant challenges face many orthodontic residency programs, particularly a shortage of full-time experienced faculty members. Due to this shortage, it is critical that program directors design comprehensive curricula that incorporate the most effective and efficient teaching methods. It is theorized that teaching effectiveness and efficiency are optimized when the course design and content closely match students' learning preferences. This survey study was designed to distinguish the learning preferences of orthodontic residents utilizing Felder and Soloman's Index of Learning Styles, which assesses student learning preferences in four dimensions using dichotomous scales, thereby providing insight into how teaching strategies can best be structured. As a secondary focus, additional questions on the survey were asked to gain information about residents' access to the Internet and comfort level with online learning so as to address acceptance of web-based courses in response to the shortage of full-time faculty members. Orthodontic residents, contacted via email, were requested to complete an online survey; 261 responses were collected. The results indicate that orthodontic residents are highly visual learners and show a preference for sensing and sequential learning strategies. In terms of information technology, the residents are comfortable with and have adequate access to current technological assets; therefore, they may be well suited for inclusion of computer-based teaching modules and other multimedia devices in their residency curriculum. PMID:19289721

Hughes, Janeen M; Fallis, Drew W; Peel, Jennifer L; Murchison, David F

2009-03-01

286

A Geometric Action for the Courant Bracket  

CERN Document Server

An important operation in generalized complex geometry is the Courant bracket which extends the Lie bracket that acts only on vectors to a pair given by a vector and a p-form. We explore the possibility of promoting the elements of the Courant bracket to physical fields by constructing a geometric action based on the Kirillov-Kostant symplectic form. The action generalizes Polyakov's two-dimensional quantum gravity which might be viewed as the geometric action for the Virasoro algebra. In particular, we show that the action arising from the centrally extended Courant bracket for a pair of a vector and a zero form is similar to the action obtained from the semidirect product of the Virasoro algebra with the affine Kac-Moody algebra with group U(1). We also discuss the general case of $p$-forms but the situation is more restricted.

Liu, X; Rodgers, V G J; Rodríguez, L; Liu, Xiaolong; Rodriguez, Leo; Zayas, Leopoldo A. Pando

2006-01-01

287

Linear odd Poisson bracket on Grassmann variables  

Energy Technology Data Exchange (ETDEWEB)

A linear odd Poisson bracket (antibracket) realized solely in terms of Grassmann variables is suggested. It is revealed that the bracket, which corresponds to a semi-simple Lie group, has at once three Grassmann-odd nilpotent {delta}-like differential operators of the first, the second and the third orders with respect to Grassmann derivatives, in contrast with the canonical odd Poisson bracket having the only Grassmann-odd nilpotent differential {delta}-operator of the second order. It is shown that these {delta}-like operators together with a Grassmann-odd nilpotent Casimir function of this bracket form a finite-dimensional Lie superalgebra. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Soroka, V.A. [Institute of Theoretical Physics, National Science Center, ' Kharkov Institute of Physics and Technology' , 310108 Kharkov (Ukraine)

1999-04-08

288

Evaluation of frictional forces between ceramic brackets and archwires of different alloys compared with metal brackets  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this study was to evaluate, in vitro, frictional forces produced by ceramic brackets and arch wires of different alloys. Frictional tests were performed on three ceramic brackets: monocrystalline (Inspire ICE, polycrystalline (InVu, polycrystalline with metal slot (Clarity, and one stainless steel bracket (Dyna-Lock. Thirty brackets of each were tested, all with .022" slots, in combination with stainless steel and nickel-titanium wires .019" × .025", at 0° and 10° angulation, in artificial saliva. Arch wires were pulled through the slots at a crosshead speed of 10 mm/min. There were statistically significant differences between the groups of brackets and wires studied (p < .05. The polycrystalline brackets with metal slots had values similar to those of conventional polycrystalline brackets, and the monocrystalline brackets had the highest frictional forces. The nickel-titanium wires produced the lowest friction. The addition of metal slots in the polycrystalline brackets did not significantly decrease frictional values. Nickel-titanium wires produced lower friction than those of stainless steel.

Ariana Pulido Guerrero

2010-03-01

289

Linear Odd Poisson Bracket on Grassmann Algebra  

OpenAIRE

A linear odd Poisson bracket realized solely in terms of Grassmann variables is suggested. It is revealed that with the bracket, corresponding to a semi-simple Lie group, both a Grassmann-odd Casimir function and invariant (with respect to this group) nilpotent differential operators of the first, second and third orders are naturally related and enter into a finite-dimensional Lie superalgebra. A connection of the quantities, forming this Lie superalgebra, with the BRST cha...

Soroka, Vyacheslav A.

2000-01-01

290

Evaluation of frictional resistance in esthetic brackets.  

Science.gov (United States)

The purpose of this study was to measure the frictional forces generated between composite, ceramic, and metal brackets and selected wire alloy-size combinations with elastomeric and stainless steel ligatures in a dry environment. Four types of composite, one ceramic, one sapphire, and one metal bracket were tested with stainless steel, nickel-titanium, and beta-titanium wires. The testing was performed with two wire sizes in the 0.018-inch slot brackets and three wire sizes in the 0.022-inch slot bracket. The recently introduced composite brackets were found to offer lower frictional resistance than the ceramic and stainless steel brackets, regardless of the wire size, wire alloy, and type of ligation. The wire alloy with the least friction was stainless steel, followed by beta-titanium and nickel-titanium. Mean variability in friction, as reflected by the magnitude of the standard deviations, was 2.7 to 3 times more with the stainless steel ligation than the elastomeric ligation. PMID:9267224

Bazakidou, E; Nanda, R S; Duncanson, M G; Sinha, P

1997-08-01

291

Effect of pre-strain on microstructure of Ni-Ti orthodontic archwires  

International Nuclear Information System (INIS)

One of the most important applications of shape memory alloy is in medicine, especially orthodontic archwires. In this category Ni-Ti orthodontic archwires is one of the oldest used materials. Biocompatibility, corrosion resistance, super elasticity, etc. are its outstanding properties. In spite of the importance of dependency of pre-strain on microstructure of Ni-Ti there are limited sources concentrated on the subject. For this reason the main purpose of the current study is determination of the effect of pre-strain on microstructure of Ni-Ti orthodontic archwires. In this regard, three-point bending was performed on the orthodontic archwire specimens to apply different amount of strain. The microstructures were compared with the un-strained wire using optical and scanning electron microscopes. The results showed that the stable phase depends strongly on the value of pre-strain. Increasing pre-strain causes to decrease martensite laths and leads the microstructure toward austenite phase

292

Body dysmorphic disorder in Iranian orthodontic patients.  

Science.gov (United States)

Patient's preoccupations with perceived defect in appearance or excessive concern about minimal flaws are among diagnostic criteria of body dysmorphic disorder (BDD). Sufferers usually seek cosmetic procedures such as orthodontic treatment. This study was conducted to estimate the prevalence of BDD among a sample of Iranian orthodontic patients. A total of 270 orthodontic patients were evaluated with BDD-YBOCS questionnaire for the diagnosis of BDD. Fifteen patients (5.5%) were screened positive for BDD. BDD was more frequent among females, singles and in younger patients. Most of the BDD patients experienced multiple previous orthodontic evaluations. The relative high prevalence of BDD among orthodontic patients in Iran offers that orthodontists should take psychologically based problems such as BDD into account while evaluating patient's orthodontic problems. PMID:25130153

Yassaei, Soghra; Goldani Moghadam, Mahdjoube; Aghili, Hossein; Tabatabaei, Seyed Mahmoud

2014-01-01

293

Distribution of White Spots after Debanding in Orthodontic Patients  

Directory of Open Access Journals (Sweden)

Full Text Available Statement of problem: Fixed orthodontic appliances can interfere with removing bacterial plaques from dental surfaces which can ultimately lead to white spot formation.Purpose: The aim of this study was to evaluate the quantity of white spots and areas of decalcification following fixed orthodontic treatment.Materials and Methods: A total of 100 patients undergoing or scheduled for fixed orthodontic treatment were divided into two groups. Group A consisted of fifty volunteers before the initiation of therapy and group B included fifty patients at the end of their treatment. In group A, the buccal surfaces of the first molars in each quadrant were examined for the presence of enamel decalcifications. After removing the orthodontic bands in group B, the buccal surfaces of the first molars in each quadrant were examined for white spots. Gender, oral hygiene level, plaque index, type of cement and duration of treatment were recorded for all patients. Binomial logistic regression, chi-square and Mann-Whitney U-tests were used for statistical analysis.Results: The number of white spots in group A was 28 (14% which was significantly lower than group B with 83 (41.5% decalcified lesions (P<0.01. Oral hygiene and duration of treatment had a significant effect on the occurrence of white spots (P<0.05.Conclusion: The results showed that patients with orthodontic bands are at higher risk for white spot formation and good oral hygiene demonstrates a protective effect on their reduction. Both professional and daily oral hygiene measures can decrease thecariogenicity of bacterial plaques in these patients.

F. Arbabzadeh Zavareh

2006-12-01

294

Corrosion behaviour of metallic biomaterials used as orthodontic wires  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: The aim of the work was evaluation of the corrosion resistance of the commercial metallic orthodontic wires from different manufacturers in simulated intra-oral environment.Design/methodology/approach: Corrosion resistance tests were carried out in artificial saliva at the temperature 37±1°C with the use of the VoltaLab® PGP 201 system for electrochemical tests. The saturated calomel electrode (SCE was applied as the reference electrode and the auxiliary electrode was a platinum foil. The evaluation of pitting corrosion was realized by recording of anodic polarization curves with the use of the potentiodynamic method. In order to evaluate crevice corrosion resistance the samples were polarized in the potential equalto 0.8 V by 900 seconds.Findings: Results of corrosion resistance tests of the CrNi, NiTi and CuNiTi wires showed comparable data of parameters obtained in the artificial saliva.Research limitations/implications: The obtained results show the influence of artificial saliva on the electrochemical corrosion of orthodontic wires. In order to demonstrate the higher risk of corrosion, which can have two consequences: a loss of the physical properties and the release of Ni ions (which have been shown to be toxic and the cause of allergic reactions - additional research on fatigue corrosion should be carried out.Originality/value: The analysis of the obtained results show that that commonly used materials for making orthodontic wires (because of their interesting properties - elasticity and shape memory can be used in different orthodontic treatment stages to correct numerous clinical conditions. The most favorable characteristics were observed for the new NiTi samples (American Orthodontics.

A. Zi?bowicz

2008-04-01

295

Evaluation of frictional forces between ceramic brackets and archwires of different alloys compared with metal brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this study was to evaluate, in vitro, frictional forces produced by ceramic brackets and arch wires of different alloys. Frictional tests were performed on three ceramic brackets: monocrystalline (Inspire ICE), polycrystalline (InVu), polycrystalline with metal slot (Clarity), and one sta [...] inless steel bracket (Dyna-Lock). Thirty brackets of each were tested, all with .022" slots, in combination with stainless steel and nickel-titanium wires .019" × .025", at 0° and 10° angulation, in artificial saliva. Arch wires were pulled through the slots at a crosshead speed of 10 mm/min. There were statistically significant differences between the groups of brackets and wires studied (p

Ariana Pulido, Guerrero; Odilon, Guariza Filho; Orlando, Tanaka; Elisa Souza, Camargo; Sérgio, Vieira.

2010-03-01

296

Quantitative and qualitative assessment of enamel surface following five composite removal methods after bracket debonding.  

Science.gov (United States)

The search for an ideal enamel surface finishing method following bracket debonding has met with equivocal response. In this study, four other methods were assessed to determine their effectiveness against the slow speed tungsten carbide bur which is regarded as the established method of removing residual composite. Orthodontic brackets were bonded on 50 premolar teeth extracted for orthodontic purpose. After debonding with a standardized technique, the teeth were randomly divided into five equal groups. Samples in each group were subjected to different finishing procedures: Group A--Ormco band removing plier. Group B--Komet slow speed tungsten carbide bur. Group C--High speed ultrafine diamond bur. Group D--Jet high speed tungsten carbide bur. Group E--High speed white stone finishing bur. For consistency, the finishing procedures were limited to 15 seconds with each particular method. The composite remnants which then remained on the enamel surface were graded by four independent raters using the Composite Remnant Index (CRI). Subsequent to this, the enamel surface was examined in a Scanning Electron Miscroscope at x203 magnification. The photomicrographs were then graded by the same four independent raters using the Surface Roughness Index (SRI). Statistical analysis with the Friedman test indicated that there was no significant difference in inter-examiner variability in both the CRI and SRI assessment, but there existed significant difference among groups (P < 0.01) for both the CRI and SRI. It was found that no single absolute method was considered to be ideal for composite removal.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7781720

Hong, Y H; Lew, K K

1995-04-01

297

Fixed appliance orthodontic treatment duration in Brunei Darussalam.  

OpenAIRE

Introduction: Fixed appliance orthodontic treatment (braces) is routinely used to address mal-positions of teeth and create esthetic smiles. Although it is desirable that treatment not exceed two years but, in practice, duration of up to two-and-a-half years is deemed acceptable. This review was undertaken to determine treatment duration for routine state-funded fixed appliance treatment in Brunei Darussalam and identify possible influencing factors. Materials and Methods: 100 consecutive cas...

Ang, Grace; Umesan, Uday Kumar

2011-01-01

298

In vitro corrosion behavior of lingual orthodontic archwires  

OpenAIRE

To investigate the in vitro electrochemical corrosive behavior of archwires used in lingual orthodontics and the effects on the phase transition temperatures. Materials and Methods. Six different types of archwires of stainless steel, titanium-molybdenum, nickel-titanium and nickel-titanium-copper were used. Corrosion tests were performed following ISO-standard 10993-15:2000. Differential scanning calorimetry and scanning electron microscopy were used. Results. The stainless steel ar...

Carlos Suárez; Teresa Vilar; Pablo Sevilla; Javier Gil

2011-01-01

299

Prevalence of malocclusion and orthodontic treatment need in Brazilian adolescents.  

OpenAIRE

AIM: To assess the prevalence and severity of malocclusion and orthodontic treatment needs in adolescents from the northeast of Brazil aged between 12 and 18 years.STUDY DESIGN: Cross sectional study.MATERIALS AND METHODS: The study population was composed by 300 adolescents (47.7% were males, 52.3% females). MAIN MEASUREMENTS: Information regarding occlusal alterations (Dental Aesthetic Index, DAI) and subjective perceptions on occlusal pathologies were collected by means of structured quest...

Alessandro Leite Cavalcanti; Dmitry José de Santana Sarmento; Jalber Almeida dos Santos; Cristiano Moura; Ana Flavia Granville-Garcia

2008-01-01

300

Microbiologically influenced corrosion of orthodontic metallic appliances.  

Science.gov (United States)

Biocorrosion (microbiologically influenced corrosion; MIC) occur in aquatic habitats varying in nutrient content, temperature, stress and pH. The oral environment of organisms, including humans, should be one of the most hospitable for MIC. Corrosion of metallic appliances in the oral region is one cause of metal allergy in patients. In this study, an inductively coupled plasma-optical emission spectrometer revealed elution of Fe, Cr and Ni from stainless steel (SUS) appliances incubated with oral bacteria. Three-dimensional laser confocal microscopy also revealed that oral bacterial culture promoted increased surface roughness and corrosion pits in SUS appliances. The pH of the supernatant was lowered after co-culture of appliances and oral bacteria in any combinations, but not reached at the level of depassivation pH of their metallic materials. This study showed that Streptococcus mutans and Streptococcus sanguinis which easily created biofilm on the surfaces of teeth and appliances, did corrode orthodontic SUS appliances. PMID:24583645

Kameda, Takashi; Oda, Hirotake; Ohkuma, Kazuo; Sano, Natsuki; Batbayar, Nomintsetseg; Terashima, Yukari; Sato, Soh; Terada, Kazuto

2014-01-01

301

Orthodontic treatment standards in Greece.  

OpenAIRE

AIM: To assess the orthodontic treatment service provided by 5 orthodontists in Greece. DESIGN: A retrospective cross-sectional study. SUBJECTS AND METHOD: One hundred cases were randomly selected from the model stores of 5 practices in the Athens area. MAIN OUTCOME MEASURED: The Index of Complexity, Outcome and Need (ICON) was used to assess the need, complexity of the problem, outcome, the degree of improvement and whether the completed case was acceptable or not. STATISTICAL ANALYSES: The...

Richmond, S.; Ikonomou, C.; Williams, B.; Rolfe, B.

2001-01-01

302

Bond strength of fiber-reinforced composite bars for orthodontic attachment.  

Science.gov (United States)

Long fiber-reinforced composites (FRC) have been shown to have enhanced mechanical properties that allow their use in orthodontic appliances as bars that join teeth to form either anchorage or active units. This study was designed to determine if the bonding of an orthodontic attachment has sufficient strength to withstand loading during clinical use. The experimental model consisted of a hydroxyapatite stone that simulated enamel, FRC bars, and a bonded metal hook. Three specimen types were compared: (1) a metal hook-pad (the control), (2) a woven FRC with a hook-pad, and (3) a unidirectional FRC with a hook-pad. Loads were applied both parallel and at 90 degrees to the tooth surface. Under no condition was the FRC pad combination weaker than the control pad. Under some loading conditions, the loads before failure were as much as 3 times greater than those for the control. The lowest strength was found with loads at 90 degrees to the tooth surface for all 3 types. Failure normally occurred in the FRC and rarely at the bracket or tooth interface. The excellent bonding of the orthodontic attachment to the FRC and the high strengths of the FRC attachment combination demonstrate the ability to form connecting bars between teeth for either anchorage or active segmental movements. These bars offer advantages in simplicity in treatment by reducing the need for some bands, attachments, or wires. PMID:11742310

Freudenthaler, J W; Tischler, G K; Burstone, C J

2001-12-01

303

Evaluation of debonding characteristics of a new collapsible ceramic bracket.  

Science.gov (United States)

A new collapsible ceramic bracket designed with a metal-lined arch wire slot has been recently introduced. The bracket also incorporates a vertical slot designed to help create a consistent bracket failure mode during debonding. The new bracket is thought to combine the esthetic advantages of ceramics and the functional advantages of debonding metal brackets. The purpose of this study was to compare (1) the shear bond strength of the new collapsible bracket with a traditional ceramic bracket, (2) the compressive force required to debond the new bracket from the enamel surface with that needed to debond a traditional metal bracket, and (3) the bond failure location when debonding the new bracket and a traditional ceramic bracket when pliers are used. Sixty-one Clarity collapsible ceramic brackets, 41 Transcend 6000 brackets, and 21 Victory Series metal brackets were bonded to the teeth with the same bonding system. The Zwick Universal Test Machine was used to determine the shear bond strength of 21 teeth bonded with the new bracket and 20 teeth bonded with the Transcend brackets. The same testing device was used to determine the compression force levels needed to debond 20 collapsible brackets and 21 metal brackets. Pliers were used to debond both the new ceramic brackets and Transcend brackets to determine the mode of bond failure. After debonding, all teeth and brackets were examined under 10x magnification. Any adhesive remaining after bracket removal was assessed according to the Adhesive Remnant Index (ARI). The findings indicated that the shear bond strength of the new Clarity ceramic bracket was comparable to that of a conventional ceramic bracket. Similarly, there were no significant differences in the results of the compression tests comparing the magnitude of forces needed to deform and debond both the new ceramic and metal brackets. The ARI scores for both the shear and compression tests indicated a similar bond failure pattern when the new collapsible brackets were compared with either the conventional ceramic or metal brackets. On the other hand, the chi-square test results indicated that, when debonding pliers were used, there was a significantly greater incidence of an ARI score of 1 with the collapsible brackets. This indicated that, when debonding the new brackets with the Weingart pliers, there was a greater tendency for most of the adhesive to remain on the enamel surface. In conclusion, the main advantage of the Clarity ceramic brackets is that they can be debonded in the same manner as metal brackets. When the new ceramic brackets are debonded with the Weingart pliers, most of the residual adhesive remained on the enamel surface, a pattern that is similar to the one observed with metal brackets. The failure at the bracket-adhesive interface decreases the probability of enamel damage but necessitates the removal of more residual adhesive after debonding. PMID:9387843

Bishara, S E; Olsen, M E; Von Wald, L

1997-11-01

304

Derived bracket construction and Manin products  

CERN Document Server

It will be shown that a derived bracket construction is a Manin product. We will extend the classical derived (bracket) product construction over binary quadratic operad-algebras. For a given differential graded binary quadratic algebra, we define a new algebra structure by derived product construction. We will show that the operad of the algebras of derived products is given by Manin's white circle product with perm-operad. As an application, we will show that the operad of prePoisson algebras is isomorphic with a black circle product of Poisson operad with preLie operad. A Koszul duality for derived product construction will be discussed.

Uchino, K

2009-01-01

305

Linear Odd Poisson Bracket on Grassmann Algebra  

CERN Document Server

A linear odd Poisson bracket realized solely in terms of Grassmann variablesis suggested. It is revealed that with the bracket, corresponding to asemi-simple Lie group, both a Grassmann-odd Casimir function and invariant(with respect to this group) nilpotent differential operators of the first,second and third orders are naturally related and enter into afinite-dimensional Lie superalgebra. A connection of the quantities, formingthis Lie superalgebra, with the BRST charge, $\\Delta$-operator and ghost numberoperator is indicated.

Soroka, V A

2000-01-01

306

Mushroom composite button for orthodontic use.  

Science.gov (United States)

Composite buttons are a valuable adjunct in orthodontic treatment mechanics and provide an esthetic alternative to metal buttons. In particular, their use warrants application in lingual orthodontic therapy or in any minor tooth movement situations. This paper describes the step by step technique for the fabrication of a mushroom shaped composite button for clinical use. PMID:25109061

Sivakumar, Arunachalam; Varm, Praveen Kumar; Padmapriya, C V; Ravipatti, S V Raghu Ram; Azharuddin, Mohammad; Sudhakar, P

2014-01-01

307

Mechanical properties of one and two-step fluoridated orthodontic resins submitted to different pH cycling regimes  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this study is to assess the in vitro shear bond strength and adhesive remnant index (ARI) of one and two-step fluoridated orthodontic resins under conditions that simulate high cariogenic challenge. Edgewise brackets for maxillary central incisors were randomly bonded to 80 bovine incisor [...] s, using either TransbondTM Plus Color Change orthodontic resin and a self-etching primer adhesive (G1; n = 40) or Orthodontic Fill Magic with a conventional acid-etch technique (G2; n = 40). Each group of resin (n = 10) was divided into: immediate shear (A- pre-cycling control), immersion in artificial remineralizing saliva (neutral saliva) for 14 days (B- post-cycling control) and pH cycling with high cariogenic challenge (C- acid saliva with pH 5.5 and D- acid saliva with pH 4.5). After 14 days of pH cycling, the shear bond strength and ARI were evaluated. Considering the shear bond strength, TransbondTM Plus Color Change resin was stronger than Orthodontic Fill Magic when it was submitted to high cariogenic challenge (p

Paula, Passalini; Tatiana Kelly da Silva, Fidalgo; Erika Machado, Caldeira; Rogério, Gleiser; Matilde da Cunha Gonçalves, Nojima; Lucianne Cople, Maia.

2010-06-01

308

Bonded Bracket Assmebly for Frameless Solar Panels  

Energy Technology Data Exchange (ETDEWEB)

In February 2011 the US Department of Energy announced their new Sunshot Initiative. The Sunshot goal is to reduce the total cost of solar energy systems by about 75 percent before the end of the decade. The DOE estimated that a total installed cost of $1 per watt for photovoltaic systems would be equivalent to 6���¢/kilowatt hour (kWh) for energy available from the grid. The DOE also estimated that to meet the $1 per watt goal, PV module costs would need to be reduced to $.50 per watt, balance of systems costs would need to be reduced to $.40 per watt, and power electronic costs would need to reach $.10 per watt. To address the BOS balance of systems cost component of the $1 per watt goal, the DOE announced a funding opportunity called (BOS-X) Extreme Balance of System Hardware Cost Reductions. The DOE identified eight areas within the total BOS costs: 1) installation labor, 2) installation materials, 3) installation overhead and profit, 4) tracker, 5) permitting and commissioning, 6) site preparation, 7) land acquisition, 8) sales tax. The BOS-X funding announcement requested applications in four specific topics: Topic 1: Transformational Building Integrated Photovoltaic (BIPV) Modules Topic 2: Roof and Ground Mount Innovations Topic 3: Transformational Photovoltaic System Designs Topic 4: Development of New Wind Load Codes for PV Systems The application submitted by ARaymond Tinnerman reflected the requirements listed in Topic #2, Roof and Ground Mount Innovations. The goal of topic #2 was to develop technologies that would result in the extreme reduction of material and labor costs associated with applications that require physical connections and attachments to roof and ground mount structures. The topics researched in this project included component cost reduction, labor reduction, weight reduction, wiring innovations, and alternative material utilization. The project objectives included: 1) The development of an innovative quick snap bracket assembly that would be bonded to frameless PV modules for commercial rooftop installations. 2) The development of a composite pultruded rail to replace traditional racking materials. 3) In partnership with a roofing company, pilot the certification of a commercial roof to be solar panel compliant, eliminating the need for structural analysis and government oversight resulting in significantly decreased permitting costs. 4) Reduce the sum of all cost impacts in topic #2 from a baseline total of $2.05/watt to $.34/watt.

Murray, Todd

2013-01-30

309

Path integral and noncommutative poisson brackets  

CERN Document Server

We find that in presence of noncommutative poisson brackets the relation between Lagrangian and Hamiltonian is modified. We discuss this property by using the path integral formalism for non-relativistic systems. We apply this procedure to the harmonic oscillator with a minimal length.

Valtancoli, P

2015-01-01

310

Branes, Quantum Nambu Brackets, and the Hydrogen Atom  

OpenAIRE

The Nambu Bracket quantization of the Hydrogen atom is worked out as an illustration of the general method. The dynamics of topological open branes is controlled classically by Nambu Brackets. Such branes then may be quantized through the consistent quantization of the underlying Nambu brackets: properly defined, the Quantum Nambu Brackets comprise an associative structure, although the naive derivation property is mooted through operator entwinement. For superintegrable sys...

Zachos, Cosmas; Curtright, Thomas

2004-01-01

311

Hydrodynamic chains and a classification of their Poisson brackets  

OpenAIRE

Necessary and sufficient conditions for an existence of the Poisson brackets significantly simplify in the Liouville coordinates. The corresponding equations can be integrated. Thus, a description of local Hamiltonian structures is a first step in a description of integrable hydrodynamic chains. The concept of $M$ Poisson bracket is introduced. Several new Poisson brackets are presented.

Pavlov, Maxim V.

2006-01-01

312

Assessment of the mechanical properties of glass ionomer cements for orthodontic cementation  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: avaliar as propriedades mecânicas de três cimentos de ionômero de vidro (CIVs) utilizados para cimentação de anéis ortodônticos. MÉTODOS: foram utilizados dois CIVs convencionais (Ketac Cem Easy mix/3M-ESPE e Meron/Voco) e um CIV modificado por resina (Multi-Cure Glass ionomer/3M-Unitek). [...] Para os testes de resistência à compressão e tração diametral, foram confeccionados 12 corpos de prova de cada material. Para os testes de microdureza, foram confeccionados 15 corpos de prova de cada material; para os testes de resistência de união ao cisalhamento, foram utilizados 45 dentes bovinos incluídos em resina acrílica, sobre os quais foi cimentada uma lâmina de anel ortodôntico com braquete soldado a ela para a realização dos ensaios. Para os testes de compressão, tração diametral e cisalhamento, foi utilizada uma máquina universal de ensaios a uma velocidade de 1mm/min; para os testes de microdureza Vickers, foi utilizado um microdurômetro com 200g de carga durante 15 segundos. Os resultados foram submetidos à análise estatística ANOVA, complementada pelo teste de Tukey ao nível de significância de 5%. RESULTADOS: os resultados demonstraram que o Multi-Cure Glass Ionomer apresentou resistência à tração diametral significativamente maior (p Abstract in english OBJECTIVE: To evaluate the mechanical properties of three glass ionomers cements (GICs) used for band cementation in Orthodontics. METHODS: Two conventional glass ionomers (Ketac Cem Easy mix/3M-ESPE and Meron/Voco) and one resin modified glass ionomer (Multi-cure Glass ionomer/3M-Unitek) were selec [...] ted. For the compressive strength and diametral tensile strength tests, 12 specimens were made of each material. For the microhardness test 15 specimens were made of each material and for the shear bond strength tests 45 bovine permanent incisors were used mounted in a self-cure acrylic resin. Then, band segments with a welded bracket were cemented on the buccal surface of the crowns. For the mechanical tests of compressive and diametral tensile strength and shear bond strength a universal testing machine was used with a crosshead speed of 1,0 mm/min and for the Vickers microhardness analysis tests a Microdurometer was used with 200 g of load during 15 seconds. The results were submitted to statistical analysis through ANOVA complemented by Tukey's test at a significance level of 5%. RESULTS: The results shown that the Multi-Cure Glass Ionomer presented higher diametral tensile strength (p

Marcel M., Farret; Eduardo Martinelli de, Lima; Eduardo Gonçalves, Mota; Hugo Mitsuo S., Oshima; Gabriela, Maguilnik; Patrícia Alves, Scheid.

2012-12-01

313

Force-Degradation Pattern of Six Different Orthodontic Elastomeric Chains  

Science.gov (United States)

Objective: An ideal orthodontic force system should exert continuous light force. Thus, many efforts have been made to improve the memory characteristics of elastomeric chains. The aim of this study was to compare elastomeric chains (ECs) claimed by their manufacturers to offer high memory with traditional ones according to their force-extension diagrams. Materials and Methods: In this in-vitro study, ECs were divided into six groups, each containing 40 pieces of chain, from three brands (American Orthodontics, GAC and Ortho-Technology). Each brand was divided into two groups with respect to their claimed characteristics (with or without memory). Each sample was stretched to twice its original length and kept constant in 37°C distilled water. Force-extension diagrams were drawn by universal testing machine at 0,1,8,24,72 hours and 1, 2, 4-week intervals. Additionally, the amounts of elongation required to deliver 200 g force were calculated. To compare the results, ANOVA and Tukey tests were performed. Results: Force-decay rate was significantly different between traditional and memory chains (p<0.05). For traditional chains, there was a substantial decay in force in the first hour and 30–40% of the force was retained at 4 weeeks. The memory chains demonstrated more constant force and retained 60% of the force. The maximum amount of elongation required to deliver 200 g force belonged to American Orthodontics memory chains (61.9% after 24hr) and the minimum to Ortho-Technology ECs (23.4% initially). Conclusion: Memory chains exhibited superior mechanical properties compared to traditional ones. For delivering the same force, memory chains required more elongation. Memory chains of GAC and American Orthodontics showed better characteristics among all chains. PMID:23323182

Mirhashemi, AH.; Saffarshahroudi, A.; Sodagar, A.; Atai, M.

2012-01-01

314

Force-Degradation Pattern of Six Different Orthodontic Elastomeric Chains  

Directory of Open Access Journals (Sweden)

Full Text Available Objective: An ideal orthodontic force system should exert continuous light force. Thus, many efforts have been made to improve the memory characteristics of elastomeric chains. The aim of this study was to compare elastomeric chains (ECs claimed by their manufacturers to offer high memory with traditional ones according to their force-extension diagrams.Materials and Methods: In this in-vitro study, ECs were divided into six groups, each containing 40 pieces of chain, from three brands (American Orthodontics, GAC and Ortho-Technology. Each brand was divided into two groups with respect to their claimed characteristics (with or without memory. Each sample was stretched to twice its original length and kept constant in 37°C distilled water. Force-extension diagrams were drawn by universal testing machine at 0,1,8,24,72 hours and 1, 2, 4-week intervals. Additionally, the amounts of elongation required to deliver 200 g force were calculated. To compare the results, ANOVA and Tukey tests were performed.Results: Force-decay rate was significantly different between traditional and memory chains (p<0.05. For traditional chains, there was a substantial decay in force in the first hour and 30-40% of the force was retained at 4 weeeks. The memory chains demonstrated more constant force and retained 60% of the force. The maximum amount of elongation required to deliver 200 g force belonged to American Orthodontics memory chains (61.9% after 24hr and the minimum to Ortho-Technology ECs (23.4% initially.Conclusion: Memory chains exhibited superior mechanical properties compared to traditional ones. For delivering the same force, memory chains required more elongation. Memory chains of GAC and American Orthodontics showed better characteristics among all chains.

AH Mirhashemi

2012-01-01

315

Periodontally accelerated osteogenic orthodontics: An interdisciplinary approach for faster orthodontic therapy  

Science.gov (United States)

Periodontally accelerated osteogenic orthodontics is a relatively new procedure designed to minimize the time taken for orthodontic treatment. The orthodontist avails of the aid of a periodontist to perform decortication of the bone and places bone graft for rapid orthodontic correction of malocclusion. A PubMed search was carried out to identify papers describing the procedure, and the data were organized in the current format. PMID:25210373

Adusumilli, Srikanth; Yalamanchi, Lohith; Yalamanchili, Pallavi Samatha

2014-01-01

316

Surface roughness of orthodontic band cements with different compositions  

OpenAIRE

OBJECTIVES: The present study evaluated comparatively the surface roughness of four orthodontic band cements after storage in various solutions. MATERIAL AND METHODS: Eight standardized cylinders were made from 4 materials: zinc phosphate cement (ZP), compomer (C), resin-modified glass ionomer cement (RMGIC) and resin cement (RC). Specimens were stored for 24 h in deionized water and immersed in saline (pH 7.0) or 0.1 M lactic acid solution (pH 4.0) for 15 days. Surface roughness readings wer...

Françoise Hélène van de Sande; Adriana Fernandes da Silva; Douver Michelon; Evandro Piva; Maximiliano Sérgio Cenci; Flávio Fernando Demarco

2011-01-01

317

Estudo comparativo da resistência adesiva da interface resina/braquete, sob esforços de cisalhamento, empregando três resinas compostas e três tipos de tratamento na base do braquete Comparative study of the shear bond strength of the resin/bracket interface, using three different resin composites and three different treatments in the base of the bracket  

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: considerando que, até o momento, a união braquete/resina é conseguida mecânica e quimicamente, esse estudo propôs avaliar: 1 a eficiência da metodologia empregada para avaliação da força de união da interface resina/braquete; 2 a resistência adesiva da interface resina/braquete sob esforços de cisalhamento, empregando três marcas comerciais de resina composta (Concise ortodôntico, Transbond-XT e Filtek-Z-250; 3 o efeito, nesta resistência adesiva, do jateamento com óxido de alumínio, aplicado na base do braquete metálico, associado ou não ao sistema adesivo resinoso dentário. METODOLOGIA: para avaliar a união adesiva, especificamente na interface resina/braquete, empregou-se uma máquina universal de ensaios e o teste preconizado foi o de cisalhamento. RESULTADOS E CONCLUSÕES: após análise estatística (análise de Variância e, posteriormente, teste de Tukey e discussão dos resultados, conclui-se que: a ocorrência de 12,5% de fraturas coesivas pode ser considerada mínima, indicando que a metodologia empregada pode ser considerada confiável para avaliar especificamente a força de união da interface resina/braquete; em relação aos tipos de materiais empregados, sem nenhum tratamento prévio, as resinas compostas Concise ortodôntico, Transbond-XT e Filtek-Z-250 apresentaram valores similares de resistência adesiva sob esforços de cisalhamento; os tratamentos que incluíam a aplicação do adesivo específico, com ou sem jateamento com óxido de alumínio na base do braquete, foram mais efetivos para a resina composta Concise ortodôntico, quando comparados ao seu grupo controle; os tratamentos de jateamento com óxido de alumínio, associado ou não ao adesivo específico na base do braquete, foram mais efetivos estatisticamente para a resina composta Transbond-XT, quando comparados ao seu grupo controle; para a resina composta Filtek-Z-250, quando utilizado o adesivo Single Bond na base do braquete, associado ou não ao jateamento com óxido de alumínio, houve uma queda dos valores de resistência ao cisalhamento. O tratamento com jateamento de óxido de alumínio na base dos braquetes melhorou todos os valores de adesividade para todos os materiais de colagem utilizados nesta pesquisa.AIM: Considering that the adhesion between the brackets and the resin is chemo-mechanical, the aim of this study was to investigate: 1 the efficacy of the method used to assess the bond strength at the resin/bracket interface; 2 the shear bond strength of the resin/bracket interface using three resin composites (Concise orthodontic, Transbond XT and Filtek Z-250; 3 the effect of sandblasting of the base of the metallic bracket with aluminum oxide, associated or not to the application of adhesive. METHODS: Shear bond strength was carried out at a universal testing machine. Data were submitted to analysis of variance and Tukey multiple comparison test. RESULS AND CONCLUSIONS: The occurrence of 12.5% of cohesive failures may be considered minimal, thus indicating that the method is appropriate to assess the bond strength at the resin/bracket interface. The different resin composites (Concise Orthodontic, Transbond XT and Filtek Z-250 used for bonding without any previous surface treatment of the bracket (control groups resulted in similar shear bond strength. The application of adhesive, with or without previous sandblasting of the base of the bracket, improved the shear bond strength for the Concise orthodontic resin composite, when compared to its control group. Sandblasting of the bracket, regardless of the combined use of adhesive, was statistically superior for the Transbond XT resin composite when compared to its control group. The application of the adhesive Single Bond in the base of the bracket, with or without previous sandblasting, promoted a decrease in the shear bond strength for the Filtek Z-250 resin composite. Sandblasting of the metallic bracket with aluminum oxide improved the adhesion at the resin/bracket interface for all the resin composites used in this stu

Adriano Lia Mondelli

2007-06-01

318

Association between gingivitis and anterior gingival enlargement in subjects undergoing fixed orthodontic treatment  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o objetivo desse estudo foi verificar a associação entre volume gengival (AG) com condições periodontais e características sócio-demográficas em sujeitos com aparelho ortodônticos fixo. MÉTODOS: uma amostra, de 330 participantes com aparelho ortodôntico fixo, por pelo menos seis mese [...] s, foi examinada, por um único examinador calibrado, para os índices de placa e gengivais, profundidade de sondagem, nível de inserção clínico e aumento de volume gengival. O status socioeconômico, tempo com aparelho ortodôntico fixo e uso de fio dental foram verificados por entrevista oral. A verificação das associações foi realizada por meio de modelos de regressão de Poisson sem ajuste e ajustados. RESULTADOS: a presença de sangramento gengival (RR 1.01; 95% IC 1.00-1.01) e o excesso de resina em torno dos braquetes (RR 1.02; 95% IC 1.02-1.03) foram associadas a um aumento do AG. Não foram encontradas associações entre características sócio-demográficas e AG. CONCLUSÃO: sangramento gengival proximal na região anterior e excesso de resina no entorno dos braquetes estão associados a níveis mais altos de aumento de volume gengival na região anterior em sujeitos com aparelho ortodôntico fixo. Abstract in english OBJECTIVE: The aim of this study was to investigate the association among gingival enlargement (GE), periodontal conditions and socio-demographic characteristics in subjects undergoing fixed orthodontic treatment. METHODS: A sample of 330 patients undergoing fixed orthodontic treatment for at [...] least 6 months were examined by a single calibrated examiner for plaque and gingival indexes, probing pocket depth, clinical attachment loss and gingival enlargement. Socio-economic background, orthodontic treatment duration and use of dental floss were assessed by oral interviews. Associations were assessed by means of unadjusted and adjusted Poisson's regression models. RESULTS: The presence of gingival bleeding (RR 1.01; 95% CI 1.00-1.01) and excess resin around brackets (RR 1.02; 95% CI 1.02-1.03) were associated with an increase in GE. No associations were found between socio-demographic characteristics and GE. CONCLUSION: Proximal anterior gingival bleeding and excess resin around brackets are associated with higher levels of anterior gingival enlargement in subjects under orthodontic treatment.

Fabricio Batistin, Zanatta; Thiago Machado, Ardenghi; Raquel Pippi, Antoniazzi; Tatiana Militz Perrone, Pinto; Cassiano Kuchenbecker, Rösing.

2014-06-01

319

CBCT imaging – A boon to orthodontics  

Science.gov (United States)

The application of innovative technologies in dentistry and orthodontics has been very interesting to observe. The development of cone-beam computed tomography (CBCT) as a preferred imaging procedure for comprehensive orthodontic treatment is of particular interest. The information obtained from CBCT imaging provides several substantial advantages. For example, CBCT imaging provides accurate measurements, improves localization of impacted teeth, provides visualization of airway abnormalities, it identifies and quantifies asymmetry, it can be used to assess periodontal structures, to identify endodontic problems, to plan placement sites for temporary skeletal anchorage devices, and to view condylar positions and temporomandibular joint (TMJ) bony structures according to the practitioner’s knowledge at the time of orthodontic diagnosis. Moreover, CBCT imaging involves only a minimal increase in radiation dose relative to combined diagnostic modern digital panoramic and cephalometric imaging. The aim of this article is to provide a comprehensive overview of CBCT imaging, including its technique, advantages, and applications in orthodontics. PMID:25544810

Machado, Genevive L.

2014-01-01

320

ORTHODONTIC MANAGEMENT IN CHILDREN WITH SPECIAL NEEDS  

Directory of Open Access Journals (Sweden)

Full Text Available Special needs individuals are children or adults pre? vented by a physical or mental condition permitting their full participation to the normal range of activities of their age groups. They usually exhibit high orthodontic treat? ment needs because of an increased prevalence and seve? rity of malocclusions. These conditions often require a coordinated craniofacial orthodontic and surgical treat? ment in a team setting, to achieve optimal outcome. Ort? hodontic treatments for patients born with facial differences tend to be more complex than ordinary ortho? dontics. This multidisciplinary treatment often starts from birth and extends up to the late teen years. The young patient may require treatment by multiple specialists, including a craniofacial surgeon, pediatrician, geneticist, neurosurgeon, ENT, speech and language therapist, pedi? atric dentist, oral surgeon and prosthodontist. The objec? tive of this paper is to summarize protocols of orthodontic treatment and to present various orthodontic management protocols regarding the children with special needs.

Adit ARORA

2013-07-01

321

CBCT imaging - A boon to orthodontics.  

Science.gov (United States)

The application of innovative technologies in dentistry and orthodontics has been very interesting to observe. The development of cone-beam computed tomography (CBCT) as a preferred imaging procedure for comprehensive orthodontic treatment is of particular interest. The information obtained from CBCT imaging provides several substantial advantages. For example, CBCT imaging provides accurate measurements, improves localization of impacted teeth, provides visualization of airway abnormalities, it identifies and quantifies asymmetry, it can be used to assess periodontal structures, to identify endodontic problems, to plan placement sites for temporary skeletal anchorage devices, and to view condylar positions and temporomandibular joint (TMJ) bony structures according to the practitioner's knowledge at the time of orthodontic diagnosis. Moreover, CBCT imaging involves only a minimal increase in radiation dose relative to combined diagnostic modern digital panoramic and cephalometric imaging. The aim of this article is to provide a comprehensive overview of CBCT imaging, including its technique, advantages, and applications in orthodontics. PMID:25544810

Machado, Genevive L

2015-01-01

322

Clinical applications of magnets in orthodontics.  

OpenAIRE

Rare earth magnets, especially the samarium-cobalt (SmCo5, Sm2Co17) and neodymium-iron-boron (Nd2Fe14B) types, have many applications in orthodontics. They can be used to move teeth, to expand the upper dental arch, to correct Class II and Class III malocclusions combined with functional appliances and to retain the therapeutic results achieved. Although the superiority of treatment results with various magnetic appliances in comparison to the conventional orthodontic appliances is supported ...

Papadopoulos, M. A.

1999-01-01

323

Miniscrew appliances and their use in orthodontics  

OpenAIRE

Anchorage is an important factor in orthodontics and must be properly managed for a successful treatment outcome. Orthodontists have historically used many devices to prevent unwanted tooth movement. The use of miniscrews as a source of skeletal anchorage has become routine in present-day orthodontic practice. Skeletal anchorage opens up alternative treatments, to borderline surgery patients for example, who can now be treated b...

Rocío Molina-Solana; Alejandro Iglesias-Linares; Enrique Solano-Reina; Daniel Torres-Lagares; Ya?n?ez-vico, R. M.

2013-01-01

324

Malocclusion Pattern (Angle's) in Mauritian Orthodontic Patients  

OpenAIRE

The aim of the study was to assess the pattern of malocclusion in different ethnic group of Mauritian population visiting the Orthodontic Department at Mauras College of Dentistry and Hospital, Republic of Mauritius. The study population comprised of 624 patients who visited the orthodontic department during 2010. The clinical examination was conducted by a well-calibrated orthodontist. The data were recorded in the case sheets and was analyzed for presence of angles class I, class II, and cl...

Durgesh, B. H.; Prakash, Prashanth; Ramakrishnaiah, Ravikumar; Subashchandra Phulari, Basavaraj; Al Kheraif, Abdul Aziz A.

2012-01-01

325

Computer-assisted learning in orthodontic education: a systematic review and meta-analysis.  

Science.gov (United States)

The purpose of this systematic review and meta-analysis was to compare the efficacy of computer-assisted learning (CAL) with traditional methods of learning in orthodontic education. Comprehensive electronic and manual searches of randomized controlled trials and prospective studies were conducted. Participants considered were undergraduate or postgraduate orthodontic students or orthodontic educators. The main outcome measure of CAL efficacy was knowledge gain. The time efficiency of the method was assessed based on the time spent learning the material, while its qualitative effect was tested by the attitudes of participants. Nine studies assessing CAL in teaching orthodontic diagnosis and treatment planning met the inclusion criteria. A statistically significantly higher knowledge gain favoring CAL was identified in studies that used pre- and post-intervention tests (weighted mean difference [WMD] 9.78 percent, 95 percent confidence intervals [CI] 2.89 percent, 16.67 percent; test of heterogeneity p=0.25). For studies that used only post-intervention tests, significantly greater efficacy was noted, but the effect size was smaller (WMD 3.79 percent, 95 percent CI 0.31 percent, 7.28 percent; test of heterogeneity p=0.003). Overall, student attitudes were positive towards CAL. No conclusions can be drawn about the time efficiency of CAL. Further studies are warranted to examine other important outcomes, including CAL efficacy in teaching other orthodontic topics, cost-effectiveness, and knowledge retention. PMID:19491350

Al-Jewair, Thikriat S; Azarpazhooh, Amir; Suri, Sunjay; Shah, Prakesh S

2009-06-01

326

Shear bond strength of metallic brackets photo-activated with light-emitting diode (LED) at different exposure times  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The purpose of this study was to compare the shear bond strength of orthodontic metallic brackets photo-activated with two different light-curing sources at different exposure times: halogen light (XL 1500, 3M ESPE) and LED light (Ortholux, 3M Unitek). Sixty bovine permanent lower incisors were inse [...] rted into PVC tubes containing plaster. The buccal surfaces were cleaned with pumice and water, and then etched with 37% phosphoric acid gel. The XT Primer bonding agent (3M Unitek) was applied to the enamel surfaces and the metallic pre-coated brackets (Transbond APC II system, 3M Unitek) were attached to upper central incisors. The teeth were randomly divided into four groups (n=15). In Group I (Control), halogen light was used for 40 seconds, while in Groups II, III, and IV were light-cured with LED light unit for 40, 10, and 5 seconds, respectively. The teeth were stored in distilled water at 37°C for 24 hours. The brackets were submitted to shear bond strength test in universal testing machine (Instron) at a crosshead speed of 0.5 mm/minute. Shear bond strength means (MPa) were 4.87 for Group I; 5.89 for Group II; 4.83 for Group III, and 4.39 for Group IV. Tukey's test detected no statistically significant differences among the groups regarding the shear bond strength (p>0.05). Neither of the types of light-curing sources or exposure times influenced the shear bond strength of metallic brackets.

Emanuel Braga, Rêgo; Fábio Lourenço, Romano.

2007-10-01

327

A critical review of older and contemporary applications of biomechanical methods in orthodontics.  

Directory of Open Access Journals (Sweden)

Full Text Available This paper attempts a review of the literature related to the applications and conclusions of methods of theoretical and applied mechanics, experimental strength of materials as well as contemporary computerized methods used in Orthodontics. These methods are evaluated based on contemporary data from both scientific fields, i.e. Mechanics and Orthodontics. Special reference and discussion is made concerning the finite element method which seems to be the best of all. There is also a brief reference of the most recent achievements of Informatics that may be used by clinical orthodontists in the near future.

Ch. G. Provatidis

1998-01-01

328

Ortodoncia acelerada y ortodoncia de transito expreso (OTE)®, un concepto contemporáneo de alta eficiencia / Accelerated orthodontics and express transit orthodontics (ETO)®, a contemporary concept of high efficiency  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish Resumen Acelerar un tratamiento de Ortodoncia permite disminuir los riesgos naturales de desmineralización del esmalte, compromiso periodontal y reabsorción radicular, además de contribuir a tener pacientes mas satisfechos y profesionales con consultas mas eficientes. Varios métodos se han evaluado [...] para mejorar la rata, magnitud y estabilidad del movimiento ortodóncico, entre ellos están, abordajes quirúrgicos, bioquímicos, farmacológicos y terapia con láser. Por otro lado, en el panorama mecánico, la evolución de los sistemas de brackets ha permitido que lleguen al mercado sistemas contemporáneos que garantizan mejores abordajes biológicos por lo menos desde el punto de vista de niveles de fuerza. La sumatoria de aproximaciones diagnósticas de alta calidad, mecanoterapias eficientes y complementos de orden físico y/o biológico y quirúrgico para acelerar los movimientos es lo que llamamos Ortodoncia de Tránsito Expreso (OTE)®, la cual es una alternativa importante para tratamientos de alta calidad y eficiencia. El propósito de esta revisión de literatura, es analizar las nuevas aproximaciones para acelerar el movimiento dentario desde el abordaje biológico, físico y quirúrgico, en sinergia con un complemento mecánico, ya sea con sistemas de Autoligado pasivo convencional o personalizado Abstract in english Accelerated Orthodontic treatment can reduce risks of enamel demineralization, root resorption and periodontal problems, and contribute to have more satisfied patients and professionals with more efficient practices. Several methods have been evaluated to improve the rate, magnitude and stability of [...] orthodontic movement, which include surgical, biochemical, pharmacological and laser therapy approaches. Furthermore, in the mechanical scope, the evolution of brackets systems has allowed contemporary systems to reach the market which guarantee better biological approaches at least from the point of view of strength levels. The sum of high quality diagnostic approaches, efficient mechanics and physical and / or biological and surgical accessories in order to accelerate the movement is what we call Express Transit Orthodontics (OTE)®, which is an important alternative for high quality and efficient treatments. The purpose of this literature review is to analyze new approaches to accelerate tooth movement from the biological, physical and surgical approach, in synergy with a mechanical complement, either conventional or customized self-ligature systems

Juan Fernando, Aristizábal-P.

2014-06-01

329

Assessment of surface friction of self-ligating brackets under conditions of angulated traction / Avaliação da fricção superficial apresentada por braquetes autoligáveis em condições de tracionamento sob angulação  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: avaliar a fricção apresentada por braquetes autoligáveis de aço inoxidável com sistema passivo de tampa deslizante sob angulação de 0 grau e 2,5 graus, e comparar o comportamento desse grupo sob angulação nula com o de um grupo de braquetes autoligáveis com sistema ativo de tampa resilient [...] e. MÉTODOS: foram utilizados 25 braquetes de caninos superiores, divididos em 5 grupos - braquetes autoligáveis passivos Damon SL II sob angulação de 0 grau e de 2,5 graus; braquetes convencionais Gemini amarrados com ligaduras elásticas sob as mesmas angulações; e um grupo formado pelo sistema ativo Time 2, sob angulação nula. A hipótese a ser testada é se artefatos autoligáveis com sistema de tampa passiva são mais efetivos no controle da fricção do que dispositivos contendo coberturas ativas. O tracionamento foi realizado segundo emprego de 25 segmentos de fio de aço inoxidável 0,020" na máquina de ensaios EMIC DL 10000 com célula de carga de 2,0kg. Cada conjunto braquete/fio foi responsável pela geração de quatro corpos de prova, totalizando-se 100 leituras. As comparações entre médias dos valores foram realizadas através da Análise de Variância (one-way ANOVA) com correções pelo coeficiente de Bonferroni. RESULTADOS E CONCLUSÃO: as médias de fricção encontradas confirmaram a hipótese em teste, de que o sistema de braquetes Damon SL II é mais eficiente no controle do atrito do que o sistema de tampa ativa sob angulação de 0 grau (p Abstract in english OBJECTIVE: The aim of this study was to assess resistance to sliding of stainless steel passive self-ligating brackets with 0° and 2.5° angulations and to compare them to active self-ligating brackets at zero angulation. The hypothesis to be tested was that passive self-ligating brackets produce low [...] er frictional forces than active self-ligating brackets. METHODS: Twenty five 0.022 x 0.028-in slot maxillary canine brackets were divided into 5 groups of 5 brackets: Damon SL II (Ormco, CA, USA) self-ligating bracket and Gemini (3M/Unitek, CA, USA) conventional bracket with angulation of 0 and 2.5° and a group of Speed 2 (American Orthodontics, WI, USA) active clip self-ligating system with zero angulation. Twenty five segments of stainless steel 0.020-in archwire (TP Orthodontics, IN, USA) were tested and each bracket/wire interface was evaluated at 4 successive points during sliding. Overall, 100 frictional values were analyzed by parametric analysis of variance and Bonferroni tests. RESULTS AND CONCLUSION: Frictional tests were performed with an Emic DL 10000 testing machine (Emic, Brazil) with a load cell of one kilogram. Passive self-ligating brackets produced lower frictional forces than active self-ligating brackets (p

Roberta, Buzzoni; Carlos N., Elias; Daniel J., Fernandes; José Augusto M., Miguel.

2012-08-01

330

Estudo comparativo da resistência adesiva da interface resina/braquete, sob esforços de cisalhamento, empregando três resinas compostas e três tipos de tratamento na base do braquete / Comparative study of the shear bond strength of the resin/bracket interface, using three different resin composites and three different treatments in the base of the bracket  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: considerando que, até o momento, a união braquete/resina é conseguida mecânica e quimicamente, esse estudo propôs avaliar: 1) a eficiência da metodologia empregada para avaliação da força de união da interface resina/braquete; 2) a resistência adesiva da interface resina/braquete sob esfor [...] ços de cisalhamento, empregando três marcas comerciais de resina composta (Concise ortodôntico, Transbond-XT e Filtek-Z-250); 3) o efeito, nesta resistência adesiva, do jateamento com óxido de alumínio, aplicado na base do braquete metálico, associado ou não ao sistema adesivo resinoso dentário. METODOLOGIA: para avaliar a união adesiva, especificamente na interface resina/braquete, empregou-se uma máquina universal de ensaios e o teste preconizado foi o de cisalhamento. RESULTADOS E CONCLUSÕES: após análise estatística (análise de Variância e, posteriormente, teste de Tukey) e discussão dos resultados, conclui-se que: a ocorrência de 12,5% de fraturas coesivas pode ser considerada mínima, indicando que a metodologia empregada pode ser considerada confiável para avaliar especificamente a força de união da interface resina/braquete; em relação aos tipos de materiais empregados, sem nenhum tratamento prévio, as resinas compostas Concise ortodôntico, Transbond-XT e Filtek-Z-250 apresentaram valores similares de resistência adesiva sob esforços de cisalhamento; os tratamentos que incluíam a aplicação do adesivo específico, com ou sem jateamento com óxido de alumínio na base do braquete, foram mais efetivos para a resina composta Concise ortodôntico, quando comparados ao seu grupo controle; os tratamentos de jateamento com óxido de alumínio, associado ou não ao adesivo específico na base do braquete, foram mais efetivos estatisticamente para a resina composta Transbond-XT, quando comparados ao seu grupo controle; para a resina composta Filtek-Z-250, quando utilizado o adesivo Single Bond na base do braquete, associado ou não ao jateamento com óxido de alumínio, houve uma queda dos valores de resistência ao cisalhamento. O tratamento com jateamento de óxido de alumínio na base dos braquetes melhorou todos os valores de adesividade para todos os materiais de colagem utilizados nesta pesquisa. Abstract in english AIM: Considering that the adhesion between the brackets and the resin is chemo-mechanical, the aim of this study was to investigate: 1) the efficacy of the method used to assess the bond strength at the resin/bracket interface; 2) the shear bond strength of the resin/bracket interface using three re [...] sin composites (Concise orthodontic, Transbond XT and Filtek Z-250); 3) the effect of sandblasting of the base of the metallic bracket with aluminum oxide, associated or not to the application of adhesive. METHODS: Shear bond strength was carried out at a universal testing machine. Data were submitted to analysis of variance and Tukey multiple comparison test. RESULS AND CONCLUSIONS: The occurrence of 12.5% of cohesive failures may be considered minimal, thus indicating that the method is appropriate to assess the bond strength at the resin/bracket interface. The different resin composites (Concise Orthodontic, Transbond XT and Filtek Z-250) used for bonding without any previous surface treatment of the bracket (control groups) resulted in similar shear bond strength. The application of adhesive, with or without previous sandblasting of the base of the bracket, improved the shear bond strength for the Concise orthodontic resin composite, when compared to its control group. Sandblasting of the bracket, regardless of the combined use of adhesive, was statistically superior for the Transbond XT resin composite when compared to its control group. The application of the adhesive Single Bond in the base of the bracket, with or without previous sandblasting, promoted a decrease in the shear bond strength for the Filtek Z-250 resin composite. Sandblasting of the metallic bracket with aluminu

Adriano Lia, Mondelli; Marcos Roberto de, Feitas.

2007-06-01

331

Enamel bonding of self-etching and phosphoric acid-etching orthodontic adhesives in simulated clinical conditions: debonding force and enamel surface.  

Science.gov (United States)

This study aimed to evaluate the effectiveness of self-etching and phosphoric acid-etching orthodontic adhesives for enamel bonding in simulated clinical conditions. By using two self-etching (Transbond Plus, TP; Beauty Ortho Bond, BB) and two acid-etching (Transbond XT, TX; Superbond Orthomite, SB) adhesives, orthodontic brackets were bonded on human premolars (n=10 for each adhesive). Ten teeth without bracket bonding, i.e., intact enamel surfaces, were used as control for SEM observation. After 7-day storage in lactic acid solution, bracket debonding force by means of debonding pliers, adhesive remnant index (ARI), and enamel surface morphology were examined. All the tested adhesives exhibited sufficient bond strength for clinical use. The ARI scores were almost the same among the four adhesives. In terms of SEM observation, the enamel surfaces in the control and TP groups showed a slight change after immersion in lactic acid solution, while the BB group showed less change on the enamel surface compared with the TP group. Meanwhile, the two acid-etching adhesives caused considerable demineralization. Taken together, these findings indicated that the action of self-etching systems was evidently more conservative. PMID:19721278

Horiuch, Shinya; Kaneko, Kazuyuki; Mori, Hiroko; Kawakami, Emi; Tsukahara, Takashi; Yamamoto, Kohji; Hamada, Kenichi; Asaoka, Kenzo; Tanaka, Eiji

2009-07-01

332

Randomized Clinical Trial of Interceptive and Comprehensive Orthodontics  

OpenAIRE

Focusing public insurance programs on interceptive orthodontics (IO) may increase access for low-income children. This report presents outcomes from a randomized clinical trial (RCT) comparing IO with comprehensive orthodontics (CO) in Medicaid patients.

King, G. J.; Spiekerman, C. F.; Greenlee, G. M.; Huang, G. J.

2012-01-01

333

Orthodontics Align Crooked Teeth and Boost Self-Esteem  

Science.gov (United States)

... news feeds delivered directly to your desktop! more... Orthodontics Align Crooked Teeth and Boost Self- esteem Article ... for the patient Reviewed: January 2012 Related Articles: Orthodontics Can Adults Wear Braces? There's More to Dentistry ...

334

Nickel: humoral and periodontal changes in orthodontic patients  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english INTRODUCTION: Although several studies have discussed nickel influence on the development of immunological reactions in orthodontic patients, it is noticed that the evidence towards the appliances, as well as towards the possible consequences of this material on the oral and general health of the in [...] dividual are still inconsistent. OBJECTIVE: The aim of this article is to present the current stage of knowledge on this issue, highlighting the most recent findings considering the periodontal and humoral aspects of allergic subjects.

Leandro Silva, Marques; Camila Alessandra, Pazzini; Mariele Cristina Garcia, Pantuzo.

2012-04-01

335

Effect of moisture on dental enamel in the interaction of two orthodontic bonding systems  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: a proposta desse estudo foi avaliar, por meio de microscopia eletrônica de varredura (MEV), a interface adesiva após a descolagem de acessórios ortodônticos, fixados em dentes bovinos com emprego de adesivo hidrofílico e hidrofóbico, em condições distintas de umidade do substrato dentário. [...] MÉTODOS: foram utilizados 20 incisivos inferiores, divididos em quatro grupos (n = 5): Grupo I , empregou-se o sistema de colagem contendo o primer hidrofílico Transbond MIP e a pasta adesiva Transbond XT, aplicados em substrato úmido; Grupo II, empregou-se o sistema de colagem primer hidrofóbico Transbond XT e pasta adesiva em substrato úmido; Grupos III e IV, os braquetes foram colados com os mesmos sistemas de união dos Grupos I e II, porém com esmalte dentário seco. Removidos os acessórios, avaliou-se em MEV, em diferentes magnificações, a interface adesiva e a interação dos sistemas adesivos com o esmalte dentário. As imagens foram avaliadas qualitativamente, observando-se o embricamento mecânico para o adesivo hidrófilo em quaisquer condições de substrato. RESULTADOS: a falta de umidade no esmalte condicionado permitiu uma melhor interação entre os materiais de ligação e a estrutura adamantina. O adesivo hidrofóbico apresentou o pior resultado de interação micromecânica quando aplicado a uma estrutura dentária úmida; já o sistema hidrofílico mostrou-se versátil, obtendo resultados aceitáveis em condições de umidade e excelente interação na ausência de contaminação. CONCLUSÃO: os autores afirmam que a melhor condição do esmalte dentário para a aplicação de primers é com a ausência de umidade. Abstract in english OBJECTIVE: The purpose of this study was to assess by means of scanning electron microscopy (SEM) the remaining adhesive interface after debonding orthodontic attachments bonded to bovine teeth with the use of hydrophilic and hydrophobic primers under different dental substrate moisture conditions. [...] MATERIAL AND METHODS: Twenty mandibular incisors were divided into four groups (n=5). In Group I, bracket bonding was performed with Transbond MIP hydrophilic primer and Transbond XT adhesive paste applied to moist substrate, and in Group II a bonding system comprising Transbond XT hydrophobic primer and adhesive paste was applied to moist substrate. Brackets were bonded to the specimens in Groups III and IV using the same adhesive systems, but on dry dental enamel. The images were qualitatively assessed by SEM. RESULTS: The absence of moisture in etched enamel enabled better interaction between bonding materials and the adamantine structure. The hydrophobic primer achieved the worst micromechanical interlocking results when applied to a moist dental structure, whereas the hydrophilic system proved versatile, yielding acceptable results in moist conditions and excellent interaction in the absence of contamination. CONCLUSION: The authors assert that the best condition for the application of primers to dental enamel occurs in the absence of moisture.

André Pinheiro de Magalhães, Bertoz; Derly Tescaro Narcizo de, Oliveira; Carla Maria Melleiro, Gimenez; André Luiz Fraga, Briso; Francisco Antonio, Bertoz; Eduardo César Almada, Santos.

2013-08-01

336

Acceptance of orthodontic miniscrews as temporary anchorage devices  

OpenAIRE

Khalid H Zawawi Department of Orthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia Objective: To study the patient’s acceptance, expectation, and experience of pain with ­orthodontic temporary miniscrews. Methods: Questionnaires were distributed to 165 potential temporary orthodontic miniscrew recipients or their parents. Using the numeric rating scale, patients who received miniscrews as part of their orthodontic treatment were also asked to rate th...

Kh, Zawawi

2014-01-01

337

General dentist orthodontic practice in foreign legal systems  

OpenAIRE

OBJECTIVE: General dentist orthodontic practice is a controversial issue and this paper aims to analyze it comparing foreign laws to Brazilian Legal System. METHODS: Regulations and scientific texts concerning orthodontic practice by general dentists, in Portuguese or English language, were sought. RESULTS AND CONCLUSION: Portugal clearly forbids general dentist orthodontic practice; United States of America do not clearly forbid general dentist orthodontic practice, but do regulate and promo...

Ivan Toshio Maruo; Armando Saga; Maria da Glória Colucci; Orlando Tanaka; Hiroshi Maruo

2012-01-01

338

External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation  

International Nuclear Information System (INIS)

This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggestypes of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

339

A bracket polynomial for graphs. III. Vertex weights  

CERN Document Server

In earlier work the Kauffman bracket polynomial was extended to an invariant of marked graphs, i.e., looped graphs whose vertices have been partitioned into two classes (marked and not marked). The marked-graph bracket polynomial is readily modified to handle graphs with weighted vertices. We present some useful formulas involving this weighted version of the bracket: analogues of series-parallel reductions involving twin vertices, and a weight adjustment that reflects the insertion of a tangle into a diagram.

Traldi, Lorenzo

2009-01-01

340

Compatibility, multi-brackets and integrability of systems of PDEs  

OpenAIRE

We establish an efficient compatibility criterion for a system of generalized complete intersection type in terms of certain multi-brackets of differential operators. These multi-brackets generalize the higher Jacobi-Mayer brackets, important in the study of evolutionary equations and the integrability problem. We also calculate Spencer delta-cohomology of generalized complete intersections and evaluate the formal functional dimension of the solutions space. The results are ...

Kruglikov, Boris; Lychagin, Valentin V.

2008-01-01

341

Compatibility, multi-brackets and integrability of systems of PDEs  

CERN Document Server

We establish an efficient compatibility criterion for a system of generalized complete intersection type in terms of certain multi-brackets of differential operators. These multi-brackets generalize the higher Jacobi-Mayer brackets, important in the study of evolutionary equations and the integrability problem. We also calculate Spencer delta-cohomology of generalized complete intersections and evaluate the formal functional dimension of the solutions space. The results are applied to establish new integration methods and solve several differential-geometric problems.

Kruglikov, B; Kruglikov, Boris; Lychagin, Valentin

2006-01-01

342

The 808 nm Laser-Assisted Surgery as an Adjunct to Orthodontic Treatment of Delayed Tooth Eruption  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction: Failure of teeth to erupt from gingival tissues at usual developmental time is called delayed tooth eruption (DTE. Delayed tooth eruption lead to prolonged fixed orthodontic treatment and its eventual complications. The purpose of the present study was to evaluate the effect of laser-assisted (808 nm surgical uncovering, on the tooth emergence and orthodontic treatment of DTE.Methods: A total of 16 orthodontic patients were included in this study and were equally assigned to an experimental and a control group. Subjects for experiment consisted of eight patients (6 girls and 2 boys with a mean age of 14±0.9 years. All patients exhibited delayed second premolar eruption. The laser wavelength was 810 nm and it was set in a continuous wave mode at a power output of 1.6 watt with a 0.3-mm diameter fiber tip. When the target tissue was sufficiently anesthetized, the tip was directed at an angle of 10 to 20 degrees to the tissue (light contact mode; and was applied continuously for approximately 12 Seconds until an acceptable tooth exposure area was visible. The facial axis of the clinical crown (FACC line represents the most prominent portion of the facial central lobe for premolars. All orthodontic brackets are aligned along this reference and are located on FA (Facial Axis point. The standard for adequate tooth eruption was the accessibility of facial axis of the clinical crown (FACC for bonding the brackets. Data gathered from the patients were statistically surveyed and compared by means of Tukey’s Test and Analysis of Variance (ANOVA.Results: All patients showed good gingival status, no significant bleeding during or immediately after the surgery, and acceptable level of healing after laser surgery. The biologic width of the teeth was preserved and no violation of this important periodontal parameter was observed. The average time for accessing the FA point in experimental group was 11±1.1 weeks and the mentioned period was increased to 25±1.8 weeks in control group. The data analysis showed that in patients with DTE, laser intervention significantly accelerated tooth eruption (P Conclusion: Laser-assisted surgical removal of the fibrous tissue over erupting premolars (DTE with appropriate irradiation parameters appears to be a promising adjunct to orthodontic treatment for bringing the premolar to the aligned and leveled dental arch.

Farnaz Younessian

2013-03-01

343

The 808 nm Laser-Assisted Surgery as an Adjunct to Orthodontic Treatment of Delayed Tooth Eruption  

Science.gov (United States)

Introduction: Failure of teeth to erupt from gingival tissues at usual developmental time is called delayed tooth eruption (DTE). Delayed tooth eruption lead to prolonged fixed orthodontic treatment and its eventual complications. The purpose of the present study was to evaluate the effect of laser-assisted (808 nm) surgical uncovering, on the tooth emergence and orthodontic treatment of DTE. Methods: A total of 16 orthodontic patients were included in this study and were equally assigned to an experimental and a control group. Subjects for experiment consisted of eight patients (6 girls and 2 boys) with a mean age of 14±0.9 years. All patients exhibited delayed second premolar eruption. The laser wavelength was 810 nm and it was set in a continuous wave mode at a power output of 1.6 watt with a 0.3-mm diameter fiber tip. When the target tissue was sufficiently anesthetized, the tip was directed at an angle of 10 to 20 degrees to the tissue (light contact mode); and was applied continuously for approximately 12 Seconds until an acceptable tooth exposure area was visible. The facial axis of the clinical crown (FACC) line represents the most prominent portion of the facial central lobe for premolars. All orthodontic brackets are aligned along this reference and are located on FA (Facial Axis) point. The standard for adequate tooth eruption was the accessibility of facial axis of the clinical crown (FACC) for bonding the brackets. Data gathered from the patients were statistically surveyed and compared by means of Tukey’s Test and Analysis of Variance (ANOVA). Results: All patients showed good gingival status, no significant bleeding during or immediately after the surgery, and acceptable level of healing after laser surgery. The biologic width of the teeth was preserved and no violation of this important periodontal parameter was observed. The average time for accessing the FA point in experimental group was 11±1.1 weeks and the mentioned period was increased to 25±1.8 weeks in control group. The data analysis showed that in patients with DTE, laser intervention significantly accelerated tooth eruption (P < 0.05). Conclusion: Laser-assisted surgical removal of the fibrous tissue over erupting premolars (DTE) with appropriate irradiation parameters appears to be a promising adjunct to orthodontic treatment for bringing the premolar to the aligned and leveled dental arch.

Seifi, Massoud; Vahid-Dastjerdi, Elahe; Ameli, Nazila; Badiee, Mohammad-Reza; Younessian, Farnaz; Amdjadi, Parisa

2013-01-01

344

Contact transformations and brackets in classical thermodynamics  

International Nuclear Information System (INIS)

The problem of coordinate transformations in classical equilibrium phenomenological thermodynamics has been solved due to the recognition of the mathematical structure of the space of thermodynamic parameters. Moreover, this structure (contact structure) enables one to introduce, in an intrinsic manner, Lie and semi-Lie algebraic structures to thermodynamics. Three types of brackets are defined which are invariants of any thermodynamically admissible transformation. The role of the so-called Legendre transformations considered by Gibbs has been recognized as a special subgroup of contact transformations. (author)

345

The quaternionic commutator bracket and its implications  

CERN Document Server

A quaternionic commutator bracket for position and momentum shows that the quaternionic wave function, \\emph{viz.} $\\widetilde{\\psi}=(\\frac{i}{c}\\,\\psi_0\\,,\\vec{\\psi})$, represents a state of a particle with orbital angular momentum, $L=3\\,\\hbar$, resulting from the internal structure of the particle. This angular momentum can be attributed to spin of the particle. The vector $\\vec{\\psi}$, points along the direction of $\\vec{L}$. When a charged particle is placed in an electromagnetic fields the interaction energy reveals that the magnetic moments interact with the electric and magnetic fields giving rise to terms similar to Aharonov-Bohm and Aharonov-Casher effects.

Arbab, Arbab I

2014-01-01

346

Experimental study of some mounting brackets to support fuel elements  

International Nuclear Information System (INIS)

In an atomic pile with vertical channels, fuel elements are stacked on one another. According to a possible assembly, fuel element can be contained by a graphite sleeve and be supported by a mounting bracket in this sleeve. Sleeves are then stacked on one another. The authors report the investigation of different designs for these mounting brackets. They describe their mechanical role and their mechanical, aerodynamic, neutronic and test conditions. They report tests performed on brackets made in graphite and on brackets made in stainless steel and graphite, and discuss the obtained results

347

Branes, quantum Nambu brackets and the hydrogen atom  

International Nuclear Information System (INIS)

The Nambu-bracket quantization of the hydrogen atom is worked out as an illustration of the general method. The dynamics of topological open branes is controlled classically by Nambu brackets. Such branes then may be quantized through the consistent quantization of the underlying Nambu brackets: properly defined, the quantum Nambu-brackets comprise an associative structure, although the naive derivation property is mooted through operator entwinement. For superintegrable systems, such as the hydrogen atom, the results coincide with those furnished by Hamiltonian quantization - but the method is not limited to Hamiltonian systems. (author)

348

Branes, Quantum Nambu Brackets, and the Hydrogen Atom  

CERN Document Server

The Nambu Bracket quantization of the Hydrogen atom is worked out as an illustration of the general method. The dynamics of topological open branes is controlled classically by Nambu Brackets. Such branes then may be quantized through the consistent quantization of the underlying Nambu brackets: properly defined, the Quantum Nambu Brackets comprise an associative structure, although the naive derivation property is mooted through operator entwinement. For superintegrable systems, such as the Hydrogen atom, the results coincide with those furnished by Hamiltonian quantization--but the method is not limited to Hamiltonian systems.

Zachos, C K; Zachos, Cosmas; Curtright, Thomas

2004-01-01

349

The Poisson bracket on free null initial data for gravity.  

Science.gov (United States)

Free initial data for general relativity on a pair of intersecting null hypersurfaces are well known, but the lack of Poisson brackets and concerns about caustics have stymied the development of a constraint free canonical theory. Here it is pointed out how caustics and generator crossings can be neatly avoided and Poisson brackets on free data are given. On sufficiently regular functions of the solution spacetime geometry these brackets match the Poisson brackets defined on such functions by the Hilbert action via Peierls' prescription. The symplectic 2-form is also given in terms of free data. PMID:19113400

Reisenberger, Michael P

2008-11-21

350

From Peierls brackets to a generalized Moyal bracket for type-I gauge theories  

CERN Document Server

In the space-of-histories approach to gauge fields and their quantization, the Maxwell, Yang--Mills and gravitational field are well known to share the property of being type-I theories, i.e. Lie brackets of the vector fields which leave the action functional invariant are linear combinations of such vector fields, with coefficients of linear combination given by structure constants. The corresponding gauge-field operator in the functional integral for the in-out amplitude is an invertible second-order differential operator. For such an operator, we consider advanced and retarded Green functions giving rise to a Peierls bracket among group-invariant functionals. Our Peierls bracket is a Poisson bracket on the space of all group-invariant functionals in two cases only: either the gauge-fixing is arbitrary but the gauge fields lie on the dynamical sub-space; or the gauge-fixing is a linear functional of gauge fields, which are generic points of the space of histories. In both cases, the resulting Peierls bracke...

Esposito, G; Esposito, Giampiero; Stornaiolo, Cosimo

2006-01-01

351

Influence of anatomical barriers on maxillary incisor root resorption after orthodontic treatment with premolar extractions  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english INTRODUCTION: Apical root resorption is a frequent and occasionally critical problem in orthodontic patients undergoing induced tooth movement. One of the factors that might influence prognosis, especially in maxillary incisors, which most frequently present resorptions, are the so-called the anatom [...] ical barriers; that is, proximity of the buccal and palatal cortical bones to the maxillary incisor roots. OBJECTIVE: The purpose of this research was to investigate whether patients with excessive vertical growth really present a small distance between the alveolar cortical bones and the maxillary incisor roots, and whether there is a correlation between this distance and the root resorption index in comparison with patients presenting horizontal growth. METHODS: The sample comprised orthodontic records of 18 patients with extraction planning of first maxillary premolars and treatment by the standard and/or preadjusted edgewise brackets. Their initial and final periapical radiographs were evaluated to determine the amount of root resorption that occurred. RESULTS: On the palatal side, patients with excessive vertical growth (Group 2 - SN-GoGn > 43º) showed a narrower alveolar bone than the horizontal growth patients (Group 1 - SN-GoGn

Antonio Geraldo de, Oliveira; Fabiana Guilhermina Ferreira, Castro.

2012-04-01

352

Orthodontic treatment in patients with reduced periodontium.  

Directory of Open Access Journals (Sweden)

Full Text Available The harmonious cooperation among the periodontist, the orthodontist, the general practitioner and other dental specialists is essential in the treatment of periodontal patients with malocclusion. Thus, treatment planning and implementation offer maximum benefit and result in good health and function of the stomatognathic system. The orthodontist’s role in these cases is crucial and raises specific demands and difficulties. The orthodontist should timely diagnose patients with periodontal disease or with increased risk of developing it. He should also have good knowledge of the orthodontic techniques most appropriate for such cases as well as those that should be avoided in order to minimize side effects. Periodontal treatment should be completed before initiation of orthodontic treatment and the periodontal status should be evaluated by the periodontist, so that both the periodontist and orthodontist agree on the treatment planning. Periodontal follow up of these patients along the course of orthodontic treatment is very important. The aim of this study is to discuss the principles of orthodontic treatment in patients with reduced periodontium, its indications and limitations, as well as current views concerning retention of orthodontic result.

N. Topouzelis

2003-01-01

353

Avaliação do atrito em braquetes autoligáveis submetidos à mecânica de deslizamento: um estudo in vitro / Evaluation of friction in self-ligating brackets subjected to sliding mechanics: an in vitro study  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese INTRODUÇÃO: o atrito gerado na interface braquete/fio durante a mecânica de deslizamento pode reduzir a eficiência da movimentação ortodôntica. O método de ligação do fio ao braquete exerce importante papel na determinação desse atrito. MÉTODOS: o presente estudo comparou a força de atrito gerada po [...] r quatro tipos de braquetes autoligáveis (Time®; Damon 2®; In-Ovation R® e Smart Clip®) com um grupo de braquetes ortodônticos convencionais (Dynalock®) associados a ligaduras elásticas tradicionais (Dispens-A-Stix®), que serviu como grupo controle. A força de atrito estático foi mensurada através da máquina universal de ensaios EMIC® DL 500 com dois fios de aço inoxidável com secção transversal 0,018" e 0,017" x 0,025". RESULTADOS: a análise de variância ANOVA e o teste de Tukey mostraram baixos níveis de atrito nos quatro braquetes autoligáveis associados ao fio 0,018" (P Abstract in english INTRODUCTION: Friction generated at the bracket/archwire interface during sliding mechanics can reduce the efficiency of orthodontic movement. The ligation method employed to tie the archwire to the bracket plays an important role in determining this friction. METHODS: This study compared the fricti [...] onal force generated by four different types of self-ligating brackets (Time™, Damon 2™, In-Ovation R™ and Smart Clip™) with a group of conventional orthodontic brackets (Dynalock™) that require the use of traditional elastomeric ligatures (ExDispens-A-Stix™), which served as the control group. Static friction force was measured using an EMIC DL™ 500 universal testing machine using stainless steel round 0.018-in and rectangular 0.017x0.025-in archwires. RESULTS: ANOVA and Tukey's test showed low levels of friction in the four self-ligating brackets in tests with the 0.018-in wire (P

Mariana Ribeiro, Pacheco; Dauro Douglas, Oliveira; Perrin, Smith Neto; Wellington Correa, Jansen.

2011-02-01

354

Uma análise dos testes in vitro de força de adesão em Ortodontia An analysis of in vitro bond strength testing in Orthodontics  

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Full Text Available O objetivo deste estudo foi analisar as metodologias empregadas em testes in vitro de força de adesão em Ortodontia. Foram selecionados nos periódicos American Journal of Orthodontics and Dentofacial Orthopedics e The Angle Orthodontist (do ano de 1993 até 2002 todos os artigos onde foi avaliada a resistência de adesão de braquetes a diferentes superfícies, através de Máquinas de Ensaio Universal Instron ou similares. Foram analisados 127 artigos, e destes 86% foram conduzidos através de ensaios de cisalhamento, ao passo que 14% foram através de ensaios de tração. Dentre os estudos com dentes humanos (68%, os pré-molares foram os mais utilizados (57%, seguidos pelos molares (31%. Quanto ao número de espécimes por grupo, 28 estudos analisaram entre 6 e 10; 30 entre 11 e 15; 33 entre 16 e 20; e 36 analisaram mais de 20 espécimes. Como solução de armazenamento, as mais empregadas foram: água destilada (43%, seguido por Timol a 0,1% (28% e Cloreto de sódio a 0,9% (12%. No que diz respeito à velocidade de operação da máquina, em 25 estudos foi de 0,5 mm/min; em 43 foi de 1,0mm/min; em 8 foi de 2,0 mm/min; e em 38 foi de 5,0 mm/min. Os autores concluem que não existe um consenso na metodologia de tais estudos, sendo então evidenciada a necessidade de uma possível padronização da técnica.The aim of this study was to examine the recent methodology used in laboratory analysis of bond strength in orthodontics. The material used was all the articles published in the American Journal of Orthodontics and Dentofacial Orthopaedics or The Angle Orthodontics in which the bonding between the bracket and several surfaces were evaluated by Instron Universal Testing Machine or similar devices. It was found 127 articles, in which 86% tested the specimens in shear mode, and 14% used the tensile technique. Among the studies with human teeth (68% premolars were the most frequent (57%, followed by molars (31%. According to the number of specimens per group, 28 studies analysed from 6 to 10; 30 from 11 to 15; 33 from 16 to 20; and 36 analyzed more than 20 specimens. According to nature of the storage solution, the most used were distilled water (43%, followed by 0.1% Timol (28% and 0.9% saline solution (12%. With regard to the cross head speed, in 25 studies were of 0,5mm/min; in 43 were of 1.0mm/min; in 8 was of 2.0mm/min; and in 38 was of 5.0mm/min. The authors concluded that there was not an agreement in the methodology on those studies, and so there is a potential need of technique standardization.

Julio Orrico de Aragão Pedra e Cal Neto

2004-08-01

355

Effects of different chlorhexidine pretreatments on adhesion of metal brackets in vitro  

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Full Text Available Abstract Objective To investigate the effect of chlorhexidine applications in various forms and concentrations on adhesion and failure modes of metal brackets in vitro. Material and methods Ninety bovine enamel specimens were allocated to six groups (n=15. Metal brackets were bonded on all specimens after chlorhexidine pre-treatments forming the following groups: (1 untreated specimens (control; (2 40% varnish (EC40, Biodent BV, Netherlands, remnants removed with brushing mimicking patient cleaning; (3 40% varnish (EC40, remnants removed with brushing mimicking professional cleaning; (4 1% varnish (Cervitec Plus, Ivoclar vivadent, Schaan, Liechtenstein, remnants not removed; (5 brushed with% 1 gel (Corsodyl, GlaxoSmithKline, Münchenbuchsee, Germany, remnants not removed; (6 immersed in 0.07% mouthrinse (Corsodyl, GlaxoSmithKline, Münchenbuchsee, Germany, remnant not rinsed. Debonding of brackets was performed using a universal testing machine. Data were analysed using one-way ANOVA and post-hoc Scheffé test. Results Group 4 performed significantly inferior than all the other groups and the control. Group 4 presented the highest number of adhesive failures at the enamel-resin interface whereas in other groups no failures at adhesive-resin interface was observed. Conclusion Presence of chlorhexidine varnish prior to bracket bonding adversely affects adhesion. Concentration of chlorhexidine pre-treatment has no influence on shear bond strength.

Frey Corinne

2012-12-01

356

Treatment of Longitudinal Epiphyseal Bracket by Excision and Polymethylmethacrylate Insertion at the Preossified Disease Stage.  

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Longitudinal epiphyseal bracket is a rare ossification anomaly involving the tubular bones of the hand or foot that have a proximal epiphysis, which becomes deformed as a result of the bracket. Untreated, the deformity becomes worse with age, because longitudinal growth cannot occur. The present report discusses the use of polymethylmethacrylate at the preossified disease stage in 2 patients with first metatarsal involvement. A medical record and radiographic review was performed for 2 children (3 feet), aged 1 year and 2 years and 5 months, who were treated with insertion of polymethylmethacrylate after excision of the aberrant epiphyseal bracket. Two different radiographic parameters (i.e., the intraosseous angulation and the metadiaphyseal length index) were used to measure the effect of treatment on the subsequent longitudinal growth of the metatarsals. An excellent clinical result after a long follow-up period was observed in 2 feet, and a good result was documented in 1 foot, which developed hallux valgus angulation. The use of polymethylmethacrylate as an interposition material after excision of the aberrant metatarsal epiphyseal bracket appeared to be an effective method of treatment during the preossified first stage of the disease, despite the general recommendation to use a cement spacer during the third ossified stage. Normal longitudinal growth of the metatarsals was noted without complications or risk of deformity recurrence. PMID:25441856

Bor, Noam; Rozen, Nimrod; Rubin, Guy

2014-10-23

357

Effect of bracket bonding with Er: YAG laser on nanomechanical properties of enamel  

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Background: The aim of this study was to compare the effects of conventional acid etching and laser etching on the nano-mechanical properties of the dental enamel using nano-indentation test. Materials and Methods: In this experimental in vitro study, buccal surfaces of 10 premolars were divided into three regions. One of the regions was etched with 37% phosphoric acid and another etched with Er:YAG laser, the third region was not etched. The brackets were bonded to both of etched regions. After thermocycling for 500 cycles, the brackets were removed and the teeth were decoronated from the bracket bonding area. Seven nano-indentations were applied at 1-31 ?m depth from the enamel surface in each region. Mean values of the hardness and elastic modulus were analyzed with repeated measures analysis of variance and Tukey HSD tests, using the SPSS software (SPSS Inc., version16.0, Chicago, Il, USA). P < 0.05 was considered as significant. Results: The hardness up to 21 ?m in depth and elastic modulus up to 6 ?m in depth from the enamel surface for laser-etched enamel had significantly higher values than control enamel and the hardness up to 11 ?m in depth and elastic modulus up to 6 ?m in depth for acid-etched enamel had significantly lower values than the control enamel. Conclusion: The mechanical properties of the enamel were decreased after bracket bonding with conventional acid etching and increased after bonding with Er:YAG laser. PMID:24688560

Alavi, Shiva; Birang, Reza; Hajizadeh, Fatemeh; Banimostafaee, Hamed

2014-01-01

358

Occlusal outcome of orthodontic treatment.  

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The aim of this study was to evaluate the overall quality of orthodontic treatment in a university clinic. Dental casts of 1870 patients (799 males and 1071 females) were evaluated at the pretreatment and posttreatment stages using the PAR index. The mean age was 13 +/- 4.1 years at the pretreatment stage and 16 +/- 3.9 years at the posttreatment stage. At both stages, mean and standard deviations of the (weighted) PAR scores were calculated, along with the percentage reductions in the weighted PAR scores. The percentage of perfect scores (score = 0) of the different components of the PAR index was calculated. The analysis of variance and t-test were used to compare quality of treatment for the variables of treatment period and gender, respectively. The mean weighted PAR scores were 27.6 +/- 10 and 7.7 +/- 6.1 for the pretreatment and posttreatment models, respectively. The mean percentage improvement was 68.9%. The mean treatment duration was 3.0 +/- 1.4 years. Great improvement was noted in 42.8% of the sample, while 49.1% of the sample showed moderate improvement, and 8.3% either did not improve or became worse. The improvement of the PAR score at the posttreatment stage could, to some extent, be explained by the treatment period: The more recent the period the better the quality. PMID:9770102

al Yami, E A; Kuijpers-Jagtman, A M; van 't Hof, M A

1998-10-01

359

Orthodontic Micro-implant-absoanchor…An Overview  

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Full Text Available Orthodontists have been straightening teeth for decades relying on the ancient physics principle "every action has a reaction," in which tooth displacement in one part of the jaw causes movement on the other as well. Use of dental implants as orthodontic anchors, however, is changing that principle by expediting treatment times and expanding possibilities for previously untreatable cases. In conventional orthodontics, teeth are used to move other teeth, but implants can serve as excellent anchors from which force is applied to move the targeted teeth without causing shifts in other teeth..Cases progress faster when implants are used as anchorage, but not because teeth are subject to higher force levels. Rather, it's is the result of a more efficient appliance design that provides the ability to move multiple teeth simultaneously rather than individually, as is necessary in conventional orthodontics.

Anitha G

2010-10-01

360

Clinical applications of magnets in orthodontics.  

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Full Text Available Rare earth magnets, especially the samarium-cobalt (SmCo5, Sm2Co17 and neodymium-iron-boron (Nd2Fe14B types, have many applications in orthodontics. They can be used to move teeth, to expand the upper dental arch, to correct Class II and Class III malocclusions combined with functional appliances and to retain the therapeutic results achieved. Although the superiority of treatment results with various magnetic appliances in comparison to the conventional orthodontic appliances is supported by several researchers, this still remains a controversial issue. The aim of this paper is to present and discuss contemporary clinical views and practical applications of magnetic force systems most often used in orthodontic and orthopedic treatment.

M.A. Papadopoulos

1999-01-01

361

Malocclusion Pattern (Angle's) in Mauritian Orthodontic Patients.  

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The aim of the study was to assess the pattern of malocclusion in different ethnic group of Mauritian population visiting the Orthodontic Department at Mauras College of Dentistry and Hospital, Republic of Mauritius. The study population comprised of 624 patients who visited the orthodontic department during 2010. The clinical examination was conducted by a well-calibrated orthodontist. The data were recorded in the case sheets and was analyzed for presence of angles class I, class II, and class III malocclusion in both male and female patients of Asian, African, Caucasian, and Chinese ethnicity aged 5-55 years. Malocclusion was found to be high in females compared to males. 414 patients (150 male?+?264 female) presented with class I, 182 patients (52 male?+?130 female) presented with class II, and 28 patients (12 male + 16 female) presented with class III. Asian ethnic group were more affected and patient seeking orthodontic treatment was high in 11-15 years age group. PMID:22655203

Durgesh, B H; Prakash, Prashanth; Ramakrishnaiah, Ravikumar; Subashchandra Phulari, Basavaraj; Al Kheraif, Abdul Aziz A

2012-01-01

362

Consequences of enamel preparation with sodium hypochlorite, polyacrylic and phosphoric acids for the bonding of brackets with resin-modified glass ionomer cements  

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Full Text Available SciELO Brazil | Language: English Abstract in english The aim of this study was to evaluate the effects of deproteinization with 5.25% sodium hypochlorite (NaOCl) prior to enamel conditioning with 10% polyacrylic acid (PAA) and 35% phosphoric acid (PA) on the bond strength (BS) of brackets bonded with resin-modified glass ionomer cement (RMGIC). One hu [...] ndred human premolars extracted for orthodontic reasons were divided into 5 groups (n = 20 in each group): G1 (control), enamel conditioning with PA, application of adhesive and bonding of brackets with TransbondTM XT composite resin (3M/Unitek, Monrovia, CA, USA); G2, enamel conditioning with PAA and bonding with RMGIC (Fuji OrthoTM LC, GC America, Alsip, IL, USA); G3, NaOCl-treated enamel, conditioning with PAA and bonding with RMGIC; G4, enamel conditioning with PA and bonding with RMGIC; and G5, NaOCl-treated enamel, conditioning with PA and bonding with RMGIC. Once the brackets were bonded, the teeth were stored in distilled water for 24 hours at room temperature and pressure until being subjected to shear stress in a Universal Mechanical Testing Machine (EMIC® DL 500, São José dos Pinhais, PR, Brazil). The BS value was higher in G1 (17.08 ± 6.39) than in any of the experimental groups (p 0.05), except between G3 (9.86 ± 2.90) and G5 (5.00 ± 2.49). No statistically significant differences were noted between the mean Adhesive Remnant Index values among the evaluated groups (p > 0.05). Conclusion: The use of NaOCl combined with PAA increased the BS of brackets bonded with RMGIC. The deproteinization of the group treated with PA reduced the shear bond strength of the brackets.

Alessandra Marques, Trindade; Tatiana Bahia Junqueira, Pereira; Perrin, Smith Neto; Martinho Campolina Rebello, Horta; Matheus Melo, Pithon; Emílio, Akaki; Dauro Douglas, Oliveira.

1423-14-01

363

Anxiety among adolescents and its affect on orthodontic compliance  

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Full Text Available Background: Investigations have suggested that poor compliance could be an indicator of poor relationship with family and could be related to the person?s personality traits. Aim: The aim of this study was to determine the effect of parents attitude, the anxiety during treatment and self-confidence/self-care of the patient on cooperation during orthodontic treatment. Materials and Methods: The study material consisted of questionnaires completed by 82 adolescent patients and their parents. The patients were divided into two groups of 42 compliant and 40 non-compliant patients. The above-mentioned questionnaries were State-Trait Anxiety Inventory-STAI, Piers-Harris Children?s Self Concept Scale and The Exercise of Self-Care Agency for the patients and Mc Master Family Assessment Device and Parental Attitude Research Instrument-PARI for the parents. Results: The problem solving and caring attitude of the father and his determinative role in the family had a positive infulence on the compliance of the child. The patients who showed better compliance also had a lower state of anxiety, which could also be explained by the positive effect of the attitude of the father in the family. Conclusion: It would be useful to overcome the increased state of anxiety of the child in the orthodontic clinic by using educational and relaxation techniques. Besides, it would be wise to ask the father to be present at the first appointment during part of the education of the child.

Trakyali G

2009-01-01

364

Frictional resistance of orthodontic wires tied with 3 types of elastomeric ligatures  

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Full Text Available SciELO Brazil | Language: English Abstract in english The aims of this study were to determine and compare frictional resistance obtained by low-friction and conventional elastomeric ligatures in the presence of artificial saliva, and observe whether this variable changed after 21 days. Super Slick® low-friction elastomeric ligatures and conventional l [...] igatures of the brands TP conventional® and Unitek® were placed on standard edgewise maxillary central incisor metal brackets, slot .022" × .028" tying rectangular orthodontic wires .018" × .025". Three experimental groups were arranged according to the type of ligature and a control group in which no wires were used. The friction values obtained between the bracket/wire/ligature set were measured using a Universal Test Machine at a speed of 20 mm/minute, at two experimental time intervals: T0 - immediately after specimen fabrication; and T1 - 21 days after fabrication and immersion in artificial saliva at 37 ºC. Conventional Unitek ligatures and the low-friction ligature (Super Slick) showed the lowest friction values at T0. After 21 days (T1), however, conventional Unitek ligatures presented the lowest value. All groups assessed from T0 to T1 showed a numerical reduction in friction values, suggesting that time, heat and humidity may cause elastic degradation, however this was not verified statistically (P > 0.05).

Amanda Carneiro da, Cunha; Mariana, Marquezan; Amanda Osório Ayres de, Freitas; Lincoln Issamu, Nojima.

2011-12-01

365

General dentist orthodontic practice in foreign legal systems  

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Full Text Available OBJECTIVE: General dentist orthodontic practice is a controversial issue and this paper aims to analyze it comparing foreign laws to Brazilian Legal System. METHODS: Regulations and scientific texts concerning orthodontic practice by general dentists, in Portuguese or English language, were sought. RESULTS AND CONCLUSION: Portugal clearly forbids general dentist orthodontic practice; United States of America do not clearly forbid general dentist orthodontic practice, but do regulate and promote campaigns to encourage public to seek specialist service; in Australia and England, corrective orthodontics are offered both by orthodontists and general dentists; it was not possible to evaluate how orthodontic services are provided in Eastern Europe; and the fact that general dentists are forbidden to practice corrective orthodontics in Brazilian Legal System is compatible to other countries policy.

Ivan Toshio Maruo

2012-04-01

366

General dentist orthodontic practice in foreign legal systems  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: General dentist orthodontic practice is a controversial issue and this paper aims to analyze it comparing foreign laws to Brazilian Legal System. METHODS: Regulations and scientific texts concerning orthodontic practice by general dentists, in Portuguese or English language, were sought. [...] RESULTS AND CONCLUSION: Portugal clearly forbids general dentist orthodontic practice; United States of America do not clearly forbid general dentist orthodontic practice, but do regulate and promote campaigns to encourage public to seek specialist service; in Australia and England, corrective orthodontics are offered both by orthodontists and general dentists; it was not possible to evaluate how orthodontic services are provided in Eastern Europe; and the fact that general dentists are forbidden to practice corrective orthodontics in Brazilian Legal System is compatible to other countries policy.

Ivan Toshio, Maruo; Armando, Saga; Maria da Glória, Colucci; Orlando, Tanaka; Hiroshi, Maruo.

2012-04-01

367

Quadratic Poisson brackets and Drinfeld theory for associative algebras  

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The paper is devoted to the Poisson brackets compatible with multiplication in associative algebras. These brackets are shown to be quadratic and their relations with the classical Yang--Baxter equation are revealed. The paper also contains a description of Poisson Lie structures on Lie groups whose Lie algebras are adjacent to an associative structure.

Balinsky, A A; Balinsky, A A; Burman, Yu M

1995-01-01

368

Evaluation of the Efficacy of Fluoride Varnish on Enamel Demineralization in Orthodontic Patients: A Split-mouth Clinical Trial  

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Full Text Available The incidence of white spot lesions in patients treated with fixed appliances is very common and can be seen as early as four weeks after band or bracket placement. Many methods can decrease or prevent white spot lesions: improving oral hygiene, modifying diet (low carbohydrate and treating with topical fluoride. Most of these methods, however, rely on patient compliance, which is unreliable and therefore not compliable. The method thus selected is the application of fluoride varnish. The purpose of this study is to evaluate the short-term effect of a single-dose application of fluoride varnish on enamel demineralization adjacent to bonded brackets. Fifteen patients who needed at least two premolars extracted for orthodontic reasons were selected. In each patient, one premolar was considered the test tooth and the other the control. Brackets were bonded on both the premolars, but only the test teeth received fluoride varnish. The premolars were extracted after 90 days and buccolingual sections of the teeth were evaluated with polarized light microscopy. The mean depth of demineralization in each lesion was then measured.

Verdine Virginia Antony

2013-01-01

369

Factors related to orthodontic treatment time in adult patients  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese INTRODUÇÃO: o tratamento ortodôntico de pacientes adultos apresenta grande variabilidade no tempo necessário para sua realização. OBJETIVO: o objetivo desse trabalho foi investigar a influência de diversas variáveis sobre o tempo de tratamento. MÉTODOS: foram examinados 70 casos clínicos, de pacient [...] es adultos, com bom resultado final, coletados em clínicas de três ortodontistas experientes, cujo acervo total inicial era de 4.723 prontuários. A influência das variáveis idade, sexo, padrão facial, severidade inicial da má oclusão (medida por meio do índice PAR), relação sagital de caninos, tipo de braquetes (estético ou metálico), exodontias, faltas às consultas e "quebras" de aparelho, sobre o tempo de tratamento (variável dependente), foram avaliadas por meio da análise de regressão linear múltipla, seguida do método Stepwise, com p Abstract in english INTRODUCTION: The length of time that it takes an orthodontist to treat adult patients varies widely. OBJECTIVE: The aim of this study was to investigate how different variables influence treatment time. METHODS: Seventy clinical case reports of successfully treated adult patients were examined. The [...] patients were selected from 4,723 records held by three experienced orthodontists. The influence exerted by the following variables on treatment time was assessed: age, sex, facial pattern, severity of malocclusion (measured by the PAR index), sagittal relationship of canines, type of brackets (ceramic or metal), tooth extractions, missed appointments and orthodontic appliance issues/breakages, the latter being the dependent variable. Assessment was performed by multiple linear regression analysis, followed by the stepwise method with P

Ana Camila Esteves de Oliveira, Melo; Lilianne Oliveira Thiers, Carneiro; Luana Farias, Pontes; Rodolpho Lobão, Cecim; José Nazareno Rufino de, Mattos; David, Normando.

2013-10-01

370

21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.  

Science.gov (United States)

...2010-04-01 false Bracket adhesive resin and tooth conditioner. 872.3750...Devices § 872.3750 Bracket adhesive resin and tooth conditioner. (a) Identification. A bracket adhesive resin and tooth conditioner is a...

2010-04-01

371

Blood contamination effect on shear bond strength of an orthodontic hydrophilic resin  

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Full Text Available SciELO Brazil | Language: English Abstract in english OBJECTIVE: The aim of this study was to assess the impact of blood contamination on shear bond strength (SBS) and bond failure pattern of metallic brackets bonded using a new hydrophilic resin. MATERIAL AND METHODS: Eighty human premolars were randomly allocated into 4 groups (n=20) according to the [...] bonding material and contamination pattern. GI: brackets bonded with the Transbond XT conventional system without contamination; GII: brackets bonded with the Transbond XT conventional system with blood contamination; GIII: brackets bonded with the Transbond Self Etching Primer and Transbond Plus Color without contamination; GIV: brackets bonded with the Transbond Self Etching Primer and Transbond Plus Color with blood contamination. The specimens were stored in distilled water at 37°C for 24 h and then submitted to SBS test at a crosshead speed of 0.5 mm/min. After bond failure, the enamel surfaces were observed under an optical microscope at 40x magnification. RESULTS: Blood contamination decreased (P

Taís de Morais Alves da, Cunha; Bruna Ariela, Behrens; Denise, Nascimento; Luciana Borges, Retamoso; Luís Filipe Siu, Lon; Orlando, Tanaka; Odilon, Guariza Filho.

2012-02-01

372

Comparación de la Respuesta Biológica generada por un sistema de brackets Convencional y brackets de Autoligado.  

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Full Text Available Antecedentes: No existe evidencia científica suficiente que soporte las ventajas del sistema de fuerzas de autoligado sobre el sistema de fuerzas convencional en ortodoncia. El objetivo de esta investigación  fue Comparar la expresión de OPG y RANKL en el ligamento periodontal de dientes sometido a fuerzas ortodóncicas generadas por un sistema de brackets de autoligado y un sistema convencional. Materiales y Métodos: Se analizó  la expresión de OPG y RANKL mediante RT-PCR en el  ligamento periodontal de 40 dientes con indicación de extracción terapéutica para ortodoncia. El grupo experimental estuvo conformado por  diez premolares que recibieron fuerzas con brackets de autoligado durante quince días  y diez premolares recibieron fuerzas  con brackets de arco recto durante 15 días antes de la extracción y 20 premolares sirvieron como grupo control. Los datos fueron analizados mediante la prueba de Kruskal–Wallis. Resultados: RANKL demostró un aumento estadísticamente significativo en el lado de presión de los dientes sometidos a los dos sistemas de fuerzas ortodóncicas. OPG no mostró diferencias entre las zonas o entre los dos sistemas de fuerzas analizados. Conclusiones: No se encontraron diferencias en la expresión de RANKL y OPG  en el ligamento periodontal de dientes movidos con técnica de ortodoncia de autoligado  comparados con los movidos con técnica de arco recto.

Liseth Wilches Buitrago

2014-09-01

373

Cytotoxicity of intermaxillary orthodontic elastics of different colors: an in vitro study  

OpenAIRE

OBJECTIVES: Natural latex does not fall into the category of materials known to be entirely inoffensive. The purpose of this in vitro study was to test the hypothesis that there is no difference in the cytotoxicity between elastics of different colors and those from different manufacturers. MATERIAL AND METHODS: Different latex intraoral elastics of different colors (5/16 = 7.9 mm, mean load) were compared. The sample was divided into 7 groups of 24 elastics each: Group T (TP Orthodontics, na...

Rogério Lacerda dos Santos; Matheus Melo Pithon; Gabriella da Silva Mendes; Maria Teresa Villela Romanos; Antônio Carlos de Oliveira Ruellas

2009-01-01

374

Minimally invasive dentistry combining orthodontic therapy and single-unit restoration.  

Science.gov (United States)

Today's restorative materials enable dental professionals to deliver predictable aesthetic enhancement, particularly for compromised teeth in the anterior region. Treating a single compromised tooth, however, requires a thorough understanding of the restorative material's optical properties, experience in its clinical performance, and awareness of therapeutic modalities that conserve sound tooth structure. In this presentation, the authors demonstrate the use of orthodontic therapy and careful treatment planning to restore a single central incisor using a minimally invasive approach. PMID:18649827

Lowe, Edward; Rego, Juan; Rego, Nelson

2008-06-01

375

In vitro analysis of femtosecond laser as an alternative to acid etching for achieving suitable bond strength of brackets to human enamel.  

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This study aims to evaluate the effect of laser irradiation and orthophosphoric acid etching on the shear bond strength (SBS) of orthodontic brackets to enamel. Three groups (n = 20) of extracted premolar teeth were randomly established depending on the laser treatment performed on the buccal surfaces: (1) no laser (control); (2) Er:YAG laser (2,940 nm, 0.8 W, 100 ?s/pulse, 10 Hz) and; (3) Ti:Sapphire laser (795 nm, 1 W, 120 fs/pulse, 1 kHz). Each group was divided into two subgroups according to whether 37%-orthophosphoric acid etching was made after laser irradiation or not. Brackets were randomly luted with Transbond(TM) XT adhesive resin. After 72 h, a SBS test was developed in a universal testing machine (crosshead speed, 0.5 mm/min). Representative specimens from each experimental subgroup were examined by means of scanning electron microscopy. Cement residuals remaining on the premolar surfaces were assessed using the adhesive remnant index. ANOVA, post-hoc tests for intergroup comparisons, chi-square test and linear regression were run for data analyses (? = 0.05). After acid etching, SBS values did not differ regardless the laser treatment. When phosphoric acid was not applied, the SBS values of the femtosecond laser group were significantly higher than for the other groups. Femtosecond laser without acid seems to be the most suitable method to improve bond strengths at the bracket/enamel interface, thus avoiding the disadvantages inherent to acid etching. PMID:23483297

Lorenzo, M C; Portillo, M; Moreno, P; Montero, J; Castillo-Oyagüe, R; García, A; Albaladejo, A

2014-05-01

376

Three-dimensional analysis of an orthodontic delta spring  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english INTRODUCTION: The purpose of this study was to analyze the force system, moment-force ratios (M/F) and von Mises stresses in an orthodontic delta spring using a 3D finite element model. The M/F ratio produced by an orthodontic spring is related to the different types of tooth movement that are likel [...] y to occur in the sagittal and occlusal planes. METHODS: Analyses were performed using a 3D finite element model, and a data acquisition system was used to validate the numerical results. RESULTS: Reactive forces between 0.0 and 2.0 N were observed along the x-axis, while null values were observed along the y- and z-axes. The maximum activation that ensured geometric stability and mechanical stresses below the elastic limit of the material was 10.0 mm. CONCLUSION: The results indicate that a delta spring can provide (i) uncontrolled tipping for activation of less than 1.0 mm; (ii) controlled counterclockwise tipping for activation between 1.0 and 4.5 mm; (iii) translation for activation between 4.5 and 5.0 mm; and (iv) controlled clockwise tipping in the sagittal plane for activation between 5.0 and 10.0 mm. No tooth movement was observed in the occlusal plane for the M/F ratios observed.

Fábio Rodrigo Mandello, Rodrigues; Paulo César, Borges; Marco Antônio, Luersen; Marcelo do Amaral, Ferreira.

2014-09-01

377

Effect of Low Llevel Therapy on Orthodontic Movement in Human  

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Full Text Available Background and Aims: Lasers with different characteristics have been used to stimulate orthodontic tooth movement. Considering the contradictory findings in this regard, this study was designed to assess the effect of low level laser therapy (LLLT on the rate of orthodontic tooth movement.Materials and Methods: In this randomized clinical trial study, 12 patients (4 boys and 8 girls; average age:16.9 ± 3.4 with extracted upper first premolars and required canine retraction into extraction site were included. While in both sides canines were retracted by NiTi coil spring, one side was exposed to GaAlAs laser (890 nm. LLLT was done (on the buccal and palatal mucosa by slow movement of probe at the beginning of the first month. Impression and cast fabrication performed at the beginning of retraction, one and two months later. The amount of retraction on the cast was measured with the aid of a reference plaque fabricated on the rogae using a digital caliper. Data were analyzed using paired sample T-test and one-sample Kolmogorov-Simirnov test. Results: There was no significant difference in the amounts of canine movement between laser exposed and control sides (P>0.05. Conclusion: The energy dose of laser used in this study (72 J per each tooth was not appropriate for increasing dental movement.

Hosseini MH

2011-12-01

378

Changes in Incisor Third-Order Inclination Resulting from Vertical Variation in Lingual Bracket Placement  

OpenAIRE

Objective: To test the null hypothesis that third-order measurements are not correlated to lingual incisor features seen on radiographs. Material and Methods: The lateral headfilms of 38 untreated, norm-occlusion subjects without incisor abrasions or restorations were used for third-order measurements of upper and lower central incisors and assessment of the inclination of four sites suitable for lingual bracket placement with reference to the occlusal plane perpendicular. Lingual section...

Kno?sel, Michael; Jung, Klaus; Gripp-rudolph, Liliam; Attin, Thomas; Attin, Rengin; Sadat-khonsari, Reza; Kubein-meesenburg, Dietmar; Bauss, Oskar

2009-01-01

379

Biological aspects of the use of permanent magnets and static magnetic fields in Orthodontics.  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this review was to address the possible biologic effects of the use of permanent magnets and static magnetic fields in orthodontics. In recent decades, the development of new, small and highly effective rare earth magnets, producing static magnetic fields, as well as their potential for multiple applications in orthodontics have significantly increased the interest in their use. The influence of static magnetic fields on osteoblastic activity and orthodontic movement still remains an issue requiring further investigation. The author examined the effect of static magnetic fields on osteoblastic cell cultures under the influence magnetic fields with an intensity of 178 mT (miliTesla, produced by neodymium-iron-boron (Ne2Fe14B magnets. The results of this in vitro study, did not show any influence of static magnetic fields on osteoblastic activity. Today, it is well known that static magnetic fields produced by small, permanent, rare earth magnets used in orthodontics have no harmful effect on tissues or cells. It seems that the better or quicker therapeutic results achieved by some researchers with permanent magnets, are due more to the biomechanical properties of some magnetic systems and less to the biologic effects of magnetic fields. When used in clinical practice, permanent magnets should be plated with biocompatible materials in order to avoid corrosion and toxicity.

M.A. Papadopoulos