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At least 19 recordsLinked to original sources
PubMed1990

[Glass ionomer cements as orthodontic bracket adhesives. An in vitro study with 4 glass ionomer cements (GIC) and 2 conventional orthodontic bracket adhesives as the comparative group].

240 orthodontic brackets were bonded to buccal surfaces of bovine teeth. As bonding material we used four glass ionomer cements without etching and two normal orthodontic bracket bonding materials with etching of enamel. Brackets of group 1 were tested with a material testing machine for shear and tensile strength after ten minutes. Brackets of group 2, 3 and 4 were tested after one day, 28 days and 98 days, respectively. In the average the bonding strength of glass ionomer cements was 50% less than the bonding strength of the comparison group with etching. The fracture of the bonding took place to 80% between the mesh base and the glass ionomer cements. Defects of the enamel surface were never observed. The bonding between mesh-base and glass ionomer cements has to be improved before the use of this bonding material can be recommended for the use in a busy practice.

Animals↗
PubMed1993

[Ethyl cyanoacrylate (Cyano-Veneer) as an orthodontic bracket adhesive. A comparative in-vitro study with Cyano-Veneer and a conventional orthodontic bracket adhesive].

According to the claims of the manufacturer, aethylcyanoacrylate can be used to bond orthodontic brackets and some orthodontists have already adopted its use for this purpose. Because, however, the use of the material as thus applied has not yet been the object of research, the question of its adhesion to tensile forces immediately after bonding and after 50, 100, and 150 days of placement in a physiologic saline solution (0.9% NaCl) is the subject of this study. 40 bovine upper incisors were extracted from 20 animals for each of the four points in time. The brackets were bonded with Cyano-Veneer and Mono-Lok according to a randomized list. Mono-Lok, an adhesive from the group of common orthodontic adhesives, functioned as the reference material. The bonding strength of the brackets in relation to the tensile forces was measured by means of a "Zwickuniversalprüfmaschine" (Zwick universal testing machine). Immediately after bonding, the cyanoacrylate demonstrated significantly higher bonding strength values than Mono-Lok. At 50, 100, and 150 days in the physiologic saline solution, the bonding strength of both materials showed no significant difference. It can thus be concluded that, when wires are employed immediately after bonding, the danger of bracket loss is significantly reduced through the use of cyanoacrylate.

Adhesives↗
PubMed1990

The shear bond strengths of stainless steel orthodontic brackets bonded to teeth with orthodontic composite resin and various fissure sealants.

Enamel decalcification (whitened areas) around orthodontic brackets during therapy is a well-recognized problem. If a fissure sealant could be used to isolate the enamel and yet withstand debonding of the bracket during therapy, this problem might be overcome. The objective of this in vitro study was to determine (1) the shear bond strengths of stainless steel orthodontic brackets bonded to teeth with an orthodontic bonding resin together with a primary coating of various fissure sealants and (2) the fracture sites of these debonded samples. Forty noncarious human canine teeth were divided into four groups of 10 teeth each. In group A, the brackets were bonded to the buccal surfaces of the prepared teeth with a macrofilled orthodontic composite resin only. In groups B, C, and D, the brackets were similarly bonded, except that the teeth were first treated with a fissure sealant--group B having a light-cured unfilled clear fissure sealant, group C having a light-cured microfilled fissure sealant, and group D having a chemically cured opaque fissure sealant. After storage at 37 degrees C for 24 hours, the brackets were subjected to a shear force in an instron machine, and the fracture strengths were recorded, together with the sites of fracture.(ABSTRACT TRUNCATED AT 250 WORDS)

Composite Resins↗
PubMed2003

In vivo inhibition of demineralization around orthodontic brackets.

Demineralization around orthodontic appliances is a problem. Suboptimal oral hygiene, long intervals between appointments, and potentially poor patient cooperation with using fluoride dentifrices and mouth rinses necessitate a compliance-free means of preventing tooth decay. The hypothesis of this study was that fluoride released by glass ionomer cement inhibits the formation of carious lesions around orthodontic brackets in vivo. Brackets were bonded on 2 first premolars in 21 randomized, consecutively selected patients 11 to 18 years old. Eleven test-group subjects were bonded with fluoride-releasing glass ionomer cement, and 10 control subjects were bonded with composite resin (no fluoride). The teeth were extracted after 4 weeks, sectioned, and evaluated quantitatively by cross-sectional microhardness testing. Fluoride levels in patient saliva were measured by the Taves diffusion method in samples taken at days 0 (baseline), 1, 2, 3, 7, 14, 21, and 28 to determine whether fluoride from the glass ionomer cement influenced the overall intraoral fluoride levels. The results demonstrated significantly more demineralization around the brackets of the control patients (P <.01, Wilcoxon signed rank test). For whole-mouth salivary fluoride levels, no significant overall difference between the groups (P >.05) and no noticeable trend within groups (P >.05) were found. These results indicate that using fluoride-releasing glass ionomer cement for bonding orthodontic brackets successfully inhibited caries in vivo. This cariostatic effect was localized to the area around the brackets and was statistically significant after 4 weeks.

Acrylic Resins↗
PubMed2001

Effect of using a new cyanoacrylate adhesive on the shear bond strength of orthodontic brackets.

During bonding of orthodontic brackets to enamel, conventional adhesive systems use three different agents: an enamel conditioner, a primer solution, and an adhesive resin. A unique characteristic of some new bonding systems is that they need neither a priming agent nor a curing light to bond brackets. Such an approach should be more cost-effective for the clinician and indirectly also for the patient. The purpose of this study was to determine the effects of using a cyanoacrylate adhesive on the shear bond strength of orthodontic brackets and on the bracket/adhesive failure mode. The brackets were bonded to extracted human teeth according to one of two protocols. Group 1: Teeth were etched with 37% phosphoric acid. After applying the primer, the brackets were bonded with Transbond XT (3M Unitek, Monrovia, Calif) and were light-cured for 20 seconds. Group 2: Teeth were etched with 35% phosphoric acid. The brackets were then bonded with Smartbond (Gestenco International, Göthenburg, Sweden). The present in vitro findings indicated that the use of the cyanoacrylate adhesive to bond orthodontic brackets to the enamel surface did not result in a significantly different (P = .24) shear bond force (mean = 5.8 +/- 2.4 MPa) as compared to the control group (mean = 5.2 +/- 2.9 MPa). The comparison of the Adhesive Remnant Index scores indicated that there was significantly (P = .006) less residual adhesive remaining on the tooth with the cyanoacrylate than on the tooth with the conventional adhesive system. In conclusion, the new adhesive has the potential to be used to bond orthodontic brackets while reducing the total bonding time.

Acid Etching, Dental↗
PubMed2003

Stereomicroscope analysis of enamel surface after orthodontic bracket debonding.

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.

Composite Resins↗
PubMed1996

The effect of etch time and debond interval upon the shear bond strength of metallic orthodontic brackets.

Groups of orthodontic brackets were attached to enamel after etching for 15, 30 or 60 seconds. They were debonded by shear forces after 5 or 15 minutes, or 24 hours. The 15 seconds etch/5 minutes debond time specimens had much lower shear strengths than other groups. Sixty-second specimens showed evidence of tooth surface damage after debonding. Fifteen seconds of etching is therefore recommended routinely for bonding brackets. If a bracket is to be ligated within 5 minutes of placement, 30 seconds etching is recommended. A 60-second etch is considered too severe and should not be used.

Acid Etching, Dental↗
PubMed2002

Roles of salivary proteins in the adherence of oral streptococci to various orthodontic brackets.

Knowledge of salivary pellicles on orthodontic brackets provides a better understanding of microbial adherence. The aim of this study was to analyze the effects of bracket pellicles on the adherence of Streptococcus gordonii and Streptococcus mutans. Bracket pellicles were formed by the incubation of 4 kinds of orthodontic brackets with unstimulated whole saliva for 2 hrs, and analyzed by electrophoresis, immunodetection, and amino acid analysis. Binding assays were then performed by the incubation of tritium-labeled streptococci with the pellicle-transfer blots and orthodontic brackets. The results showed that low-molecular-weight mucin, alpha-amylase, secretory IgA, acidic proline-rich proteins, and cystatins adhered to all kinds of brackets, though the amino acid composition of pellicles differed between bracket types. Some of these proteins increased the binding of S. gordonii to saliva-coated brackets. However, salivary pellicles decreased the binding of S. mutans. Collectively, salivary pellicles were found to play a significant role in the initial adhesion of oral streptococci to orthodontic brackets.

Adult↗
PubMed2006

A comparison of the shear-peel and third-order bond strengths of orthodontic brackets with 2 etch techniques and the role of bracket asymmetry.

INTRODUCTION: Innovations in orthodontic bonding are inevitably followed by a flurry of studies to ascertain efficacy. Unfortunately, the published reports are often contradictory or highly variable. The primary purpose of this study was to analyze protocols that measure orthodontic bracket bond strength. The effects of loading mode and the role of bracket asymmetry were examined. The secondary goal was to test a self-etch enamel preparation system. MATERIALS AND METHODS: Flattened stainless steel orthodontic brackets (.022-in Victory Series, 3M Unitek, Monrovia, Calif) were bonded to a total of 192 flattened bovine incisors with a resin composite bonding agent (Transbond XT, 3M Unitek.) The enamel was prepared with traditional, two-step (TS) acid (37% phosphoric acid gel) etching and priming (Transbond XT Primer, 3M Unitek) or with a single step (SS) self-etch (Transbond Plus, 3M Unitek) material. Cement thickness was held constant and bonding was done under controlled temperature and humidity. The brackets were debonded in the occlusogingival and in the gingivocclusal directions (ie, the 2 senses of shear-peel) and using a new technique in the buccal-root and in the lingual-root directions (ie, the 2 senses of a third-order moment.) RESULTS: Data showed no significant differences between TS and SS regardless of load modality. However, significant differences were revealed between the senses of debonding, indicating bracket asymmetry effects. CONCLUSIONS: The wide clinical use of these newer self-etching primers has been supported by these limited findings. A new third-order debonding protocol has been demonstrated to be a useful tool. Bracket asymmetry affects some bond strength values, and there is a need for standardization of testing protocols.

Acid Etching, Dental↗
PubMed1996

A three-year clinical trial using a glass ionomer cement for the bonding of orthodontic brackets.

Recent clinical studies measuring orthodontic bracket failure, when using glass ionomer cement as an adhesive, have reported a wide range of percentages of bracket failure. The present study recorded bracket failure over a 3-year period, longer than had been previously measured. Seventeen participants were randomly assigned to one of two treatment groups, either using glass ionomer cement or composite resin for bonding. In each group, brackets were bonded to incisors, canines, and premolars. Bracket failure was measured over the duration of comprehensive orthodontic treatment for all participants. Brackets bonded with the glass ionomer cement were more likely to fail (log-rank test; P < or = 0.022). This difference was clinically significant. At the present time, the disadvantage of extra bracket failures appears to outweigh potential advantages when considering glass ionomer cement for the routine bonding of orthodontic brackets.

Adhesives↗
PubMed2003

Adhesives for fixed orthodontic brackets.

BACKGROUND: Bonding of orthodontic brackets to teeth is important to enable effective and efficient treatment with fixed appliances. The problem is bracket failure during treatment which increases operator chairside time and lengthens treatment time. A prolonged treatment is likely to increase the oral health risks of orthodontic treatment with fixed appliances one of which is irreversible enamel decalcification. OBJECTIVES: To evaluate the effectiveness of different orthodontic adhesives for bonding. SEARCH STRATEGY: Electronic databases: the Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. Date of most recent searches: August 2002 (CENTRAL) (The Cochrane Library Issue 2, 2002). SELECTION CRITERIA: Trials were selected if they met the following criteria: randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing two different adhesive groups. Participants were patients with fixed orthodontic appliances. The interventions were adhesives that bonded stainless steel brackets to all teeth except the molars. The primary outcome was debond or bracket failure. DATA COLLECTION AND ANALYSIS: Data were recorded on decalcification as a secondary outcome, if present. Information regarding methods, participants, interventions, outcome measures and results were extracted in duplicate by pairs of reviewers (Nicky Mandall (NM) and Rye Mattick (CRM); Declan Millett (DTM) and Joy Hickman (JH2)). Since the data were not presented in a form that was amenable to meta-analysis, the results of the review are presented in narrative form only. MAIN RESULTS: Three trials satisfied the inclusion criteria. A chemical cured composite was compared with a light cure composite (one trial), a conventional glass ionomer cement (one trial) and a polyacid-modified resin composite (compomer) (one trial). The quality of the trial reports was generally poor. REVIEWER'S CONCLUSIONS: It is difficult to draw any conclusions from this review, however, suggestions are made for methods of improving future research involving orthodontic adhesives.

Dental Cements↗
PubMed2002

Effect of using self-etching primer for bonding orthodontic brackets.

Questions over the use of self-etching primers with composite resin adhesives in the bonding of orthodontic brackets remain unsolved. In addition, there are no previous reports on the efficacy of self-etching primers with resin-modified glass ionomer cements for bonding orthodontic brackets in orthodontic dentistry. The purpose of this study was to determine the shear bond strengths of orthodontic brackets bonded with one of four protocols: (1) a composite resin adhesive used with 40% phosphoric acid, (2) the same composite resin used with Megabond self-etching primer, (3) a resin-modified glass ionomer cement adhesive used with 10% polyacrylic acid enamel conditioner, and (4) the same resin-modified glass ionomer cement used with Megabond self-etching primer. The appearance of the tooth surfaces after acid etching or priming was observed with a field-emission scanning electron microscope (FE-SEM). When used with resin-modified glass ionomer cement, Megabond self-etching primer gave no significantly different shear bond strength compared with polyacrylic acid etching. But when used with composite resin adhesive, Megabond self-etching primer gave significantly lower shear bond strength than phosphoric acid etching. However, the shear bond strength of orthodontic brackets bonded with composite resin adhesive after Megabond priming was almost the same as that of brackets bonded with resin-modified glass ionomer cement after polyacrylic acid etching. FE-SEM observation revealed that Megabond self-etching primer produced less dissolution of enamel surface than did phosphoric acid and polyacrylic acid etching. Megabond self-etching primer may be a candidate for bonding orthodontic brackets using the resin-modified glass ionomer cement for minimizing the amount of enamel loss.

Acid Etching, Dental↗
PubMed1995

Interlayer formation and its effect on debonding polycrystalline alumina orthodontic brackets.

During the debonding of ceramic orthodontic brackets, there is a risk of causing fractures, cracks, or flaking of enamel or of the bracket itself. Preliminary work on the resin-enamel interface under bonded brackets with the indirect (modified Thomas) or the thermal-cured indirect bonding techniques revealed an interlayer of unfilled resin formed between the filled resin and the enamel surface. The direct bonding technique, on the other hand, showed no such layer. This study was designed to determine the effect of the interlayer on conventional debonding techniques for polycrystalline ceramic orthodontic brackets. Variables examined were bracket failure or fracture (BF), amount of remnant adhesive (ARI), and enamel damage. Brackets were bonded to 90 fresh bovine teeth. These were divided into three groups of 30 each, based on three methods of bonding, i.e., direct, indirect (modified Thomas), and an indirect technique that used a thermal-cured resin. Each bonding group was further divided into three groups of 10 each, based on the type of debonding technique used, i.e., lift off, delamination, and twisting. Brackets bonded by the indirect (modified Thomas, BF mean = 0.27, ARI mean = 0.93) and the indirect technique that used a thermal-cured resin (BF mean = 0.03, ARI mean = 0.43) resulted in an overall significantly lower failure (p < 0.01) and ARI score on debonding (p < 0.0001) compared with those bonded by the direct technique (BF mean = 1.03, ARI mean = 1.97). Specimens evaluated under the stereomicroscope revealed that the brackets bonded with the indirect techniques debonded at the filled-unfilled resin interface or within the interlayer of unfilled resin.(ABSTRACT TRUNCATED AT 250 WORDS)

Aluminum Oxide↗
PubMed1995

Retention capacity of the bracket bases of new esthetic orthodontic brackets.

Tensile bond strength and bond failure locations were evaluated in vitro for three types of direct bonding cements (self-cured diacrylate, dual-cured diacrylate, and dual-cured glass ionomer) with four types of brackets (stainless steel, polycarbonate, ceramic, and ceramic-polycarbonate) by using a plastic cylinder as the substrate. A highly filled, self-cured diacrylate cement gave the highest bond strength values with the polycarbonate, stainless steel, and ceramic-polycarbonate brackets. A dual-cured diacrylate cement gave the highest bond strength with a mechanically retained ceramic bracket. The dual-cured glass ionomer cement gave the highest bond strength values with a silanated ceramic bracket. All bond failures occurred at the bracket/cement interface with the stainless steel bracket, whereas failure locations were at the bracket/cement interface and within the cement with the polycarbonate bracket. Bond failures occurred between bracket and cement, within the cement, and within the bracket with the ceramic brackets.

Acrylic Resins↗
PubMed1990

Shear bond strength of ceramic orthodontic brackets to enamel.

The recent introduction of ceramic orthodontic brackets has generated interest among orthodontists. The aim of this investigation was to evaluate the in vitro shear bond strengths to enamel of four ceramic orthodontic brackets and one stainless steel bracket in trials with two separate acid-etching times for enamel. Eighty extracted human central incisors were prepared for bonding to Starfire, Allure, Transcend, Quasar, and stainless steel (in the control group) orthodontic bracket systems. Enamel etching times of 15 seconds and 60 seconds were used. There was a total of 10 groups. After acid etching, one coat of low-viscosity bonding agent was applied and the brackets were bonded to etched enamel with Concise orthodontic bonding resin. The bonded test specimens were stored in distilled water at 37 degrees C for 14 days, after which they were thermocycled for 500 cycles (5 degrees C to 60 degrees C). The bonds were stressed to failure in an Instron machine at a crosshead speed of 0.02 inch per minute. The shear bond strengths were calculated and Weibull analysis was used to obtain a shape factor (the slope of the straight line and a measure of predictability) and the characteristic level (the 63.2% bond strength value of median rank on the strength line) for each group. Predictability and high bond strength, along with other factors, are important in the clinical selection of a bracket system. When either predictability or bond strength was considered independently, several bracket systems, coupled with a particular etch time, had either high predictability or high bond strength. The highest predictability and the highest bond strength were both found with the Allure bracket system.

Acid Etching, Dental↗
PubMed2003

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

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.

Dental Bonding↗
PubMed1993

The influence of bracket material, ligation force and wear on frictional resistance of orthodontic brackets.

Planar static frictional phenomena were investigated for two types of ceramic and one type of stainless steel orthodontic bracket against rectangular stainless steel archwire. The brackets studied were 'Starfire' (single crystal aluminium oxide), 'Allure III' (polycrystalline aluminium oxide), and 'Dentaurum' (stainless steel). The investigative parameters were: bracket material, force of ligation and whether the brackets were new or 'worn'. Without exception, both types of ceramic bracket produced greater frictional resistance than the stainless steel brackets throughout testing. At a ligation force of 500 g, the Starfire bracket gave the greatest frictional resistance. At ligation forces of 200 and 50 g, the greatest frictional resistance was seen with Allure III. After a period of simulated wear, frictional resistance of Starfire tended to increase at the greatest ligation load while that of both ceramics decreased slightly at the two lower ligation loads. The ceramic brackets caused abrasive wear of the archwire surfaces and the consequent wear debris may have contributed to the changes in frictional resistance seen with Starfire and Allure III. Dentaurum brackets produced minimal frictional resistance in any test and negligible change with wear.

Aluminum Oxide↗
PubMed2006

Orthodontic bracket bonding: enamel bond strength vs time.

INTRODUCTION: Tests of bond strength between orthodontic brackets and enamel are generally conducted after at least 24 hours storage in water. However, debonding might occur soon after bracket placement during orthodontic treatment. We investigated the rate of bond strength development for orthodontic adhesives in bracket bonding. METHODS: Four orthodontic adhesive systems were examined. Bovine incisors were mounted in self-curing acrylic resin, and the facial surfaces were wet-ground to expose flat enamel. Orthodontic brackets were bonded according to the manufacturers' instructions. Shear bond strengths were measured after storage in water for 5, 10, and 60 minutes, and 24 hours. Differences between bond strengths at 24 hours and the other test periods were statistically analyzed. RESULTS: All materials tested had the highest bond strengths at 24 hours, and bond strength increased with storage time. The earliest time point at which there was no significant difference in bond strength compared with that at 24 hours was defined as the initial stable time. Differences in this value might have clinical implications for the assessment of orthodontic adhesives, which can incur high stresses immediately after placement. CONCLUSIONS: The rate of development of enamel bond strength must be considered to ensure sufficient maturation of orthodontic adhesives before functional loading.

Animals↗