Esthetic Brackets Research Articles

Colour stability of 3D-printed resin orthodontic brackets.

To evaluate the colour stability of polymeric resins that could be used to 3D-print orthodontic brackets. In vitro, laboratory study. Disc-shaped specimens were fabricated via 3D printing using three resins: Dental LT; Dental SG; and Clear. Five conditions were evaluated for each resin (n = 10 per treatment per resin) to assess its corresponding effect on colour and translucency: immersion in (1) red wine, (2) coffee, (3) tea and (4) distilled water (control), and (5) exposure to accelerated aging. Colour and translucency measurements were made before and after exposure using a spectrophotometer. Mean colour differences (ΔE00) and changes in translucency parameter (ΔTP00) were calculated for each sample using the CIEDE2000 colour difference formula. Statistically significant effects of the resin material, the treatment condition and interactions effects of material and condition were observed for ΔE00 and ΔTP00 (P < 0.001). The most pronounced changes in colour (ΔE00) were a result of the staining effects of wine on all three resins, ranging from 14.5 ± 0.6 to 20.8 ± 1.2. Dental LT, Dental SG and Clear resins all showed changes in colour when exposed to certain staining agents. Dental SG and Clear resins exhibited changes in colour with aging, while the colour of Dental LT resin remained stable with aging. The colour changes of the resins investigated does not support their use in 3D-printed aesthetic bracket applications.

Do orthodontists aim to decrease the duration of fixed appliance treatment?

OBJECTIVES:The aim of the present study was to investigate the trends in the use of fixed appliance and accelerated orthodontics to decrease the treatment duration. Further, this study aimed to assess the effect of demographic factors on the participant's choice of treatment modality.METHODS:This was a cross-sectional study in the form of questionnaire-based online survey especially designed and distributed to 265 orthodontists via email. The questions aimed to collect basic information about the participants and respondents’ choices for decreasing the treatment duration. The data were analyzed according to gender, level of academic education and years of clinical experience using Chi-square test.RESULTS:A response rate of 85.2% was reported. Most of the orthodontists aimed to reduce the treatment duration by the biomechanical (66.8%) and surgical approaches (27.4%). The use of sliding mechanics (69.4%) and one-step retraction was more common (66.3%). MBT bracket prescription was more prevalent (51.7%), followed by Roth (41.1%). Conventional brackets were used more than self-ligating brackets, and aesthetic brackets were avoided by one third of the respondents. NiTi wires were the most commonly used wires during the alignment stage (44.2%). However, the effect of gender, years of clinical experience and specialty level of education showed some effects on the use of certain techniques and clinical practice of the respondents.CONCLUSIONS:Most of the orthodontists aimed to decrease orthodontic treatment duration by using biomechanical and surgical approaches. Gender and clinical experience to a certain extent affected the participants’ choice during orthodontic treatment.

Do dental bleaching sessions prior to orthodontic treatment change the bond strength of esthetic brackets?

ABSTRACTObjective: The aim of this experimental in vitro study was to evaluate whether dental bleaching performed before orthodontic treatment change the shear bond strength (SBS) of monocrystalline and polycrystalline esthetic brackets. Methods: Sixty (60) bovine incisors teeth were used and randomly divided into the following six groups (n=10): SCP (without bleaching/polycrystalline brackets); SCM (without bleaching/monocrystalline brackets); 1CP (one bleaching session/polycrystalline brackets); 1CM (one bleaching session/monocrystalline brackets); 3CP (three bleaching sessions/polycrystalline brackets); and 3CM (three bleaching sessions/monocrystalline brackets). The brackets were bonded seven days after the bleaching sessions. The samples were submitted to the SBS test in a universal testing machine (Instron model 4411) at 1 mm/min crosshead speed. The two-way analysis of variance (ANOVA) and the Tukey tests were performed at a 5% level of significance. After the mechanical test, samples were evaluated to determine the adhesive remnant index (ARI). Results: The SBS values were significantly higher for the monocrystalline brackets, when compared with the polycrystalline type (p< 0.0001), and significantly higher with three bleaching sessions than without bleaching (p< 0.0436). The ARI showed predominance of failures between the bracket and resin for all the groups (score 3). Conclusion: Three dental bleaching sessions increased the SBS values. Monocrystalline brackets showed higher SBS values than the polycrystalline type.

Clear aligners, the aesthetic solution: a review

In the recent past, the demand for adult orthodontic treatment has increased multiple folds. As a repercussion of this stipulation, invisible orthodontic treatment has expanded its horizon. Efforts of using aesthetic brackets, wires, and lingual techniques to meet the expectations of adult patients have been practised. Though these techniques seemed to be promising in the initial days, soon decreased in popularity due to drawbacks associated with them. Clear aligners were offered as a newer and superior aesthetic alternative to overcome the difficulties associated with prior aesthetic approaches. These aligners are made up of different thermoplastic materials intended to move the malpositioned teeth in the desired corrected position following push mechanics. This article deals with new generation orthodontic treatment using aligners. It deals with history, generations, different materials used, and the distances yet to be travelled to become the benchmark and replace the existing conventional braces. This paper also gives a bird’s eye view of the method of aligner fabrication and the significant differences between the regular braces and aligners used in orthodontics.

The impact of various staining substances and immersion time on the stainability of bonded sapphire brackets with three kinds of light cure orthodontic adhesives (An in-vitro study)

Background: The need of the patient for a more reasonable esthetic orthodontic intervention has risen nowadays. Thus, orthodontists make use of esthetic orthodontic materials like brackets, ligature elastics, and arch wires. The esthetic brackets come as different forms of materials, such as ceramic brackets, which have their stainability remaining as the most important consideration for the patients and the orthodontists. This study aimed to compare the staining effects of various staining materials, including black tea, cigarette smoke and Pepsi, as well as the time effect on the color stability of sapphire ceramic brackets bonded with three kinds of light cure orthodontic adhesives: Transbond, Resilience and Enlight. Materials and Methods: Three hundred sixty sapphire brackets were utilized and divided into three different groups (120 brackets per group) based on the type of bonding material. Each group was further subdivided into four subgroups (30 brackets each) based on the media in which the brackets were fully immersed, including distilled water, black tea, cigarette smoke and Pepsi. Moreover, each of these subgroups were further subdivided, based on the time of immersion relative to each media, into 3 different smaller subgroups (10 brackets each): one day, 7 days and 14 days with incubation at 37°C. A UV-visible type of spectrophotometer was utilized in order to perform a light absorption test. ANOVA and post hoc LSD tests were used for comparison. Results: The smoke of cigarette appeared to be the highest potent staining type among the tested materials followed by Pepsi and tea. The staining effects of all kinds of staining materials in relation to the bonded brackets color with all adhesive types were raised with increased time of immersion. Conclusion: The patient’s cooperation and habits should be taken into consideration when using sapphire orthodontic brackets. In addition, the patients should be instructed to decrease the consumption of staining beverages. Keywords: Stainability, staining materials, sapphire brackets.&#x0D; &#x0D;

Esthetic perception of clear aligner therapy attachments using eye-tracking technology

The purpose of this research was to assess and compare esthetic perceptions of clear aligner therapy with attachments and esthetic brackets by measuring differences in eye fixations using eye-tracking technology. The sample involved 250 adult subjects. The subjects gave verbal consent, then viewed photographs showing 4 variations of orthodontic appliances: clear aligner control with minimal attachments, clear aligner with anterior and posterior attachments, esthetic brackets, and clear aligner with posterior attachments. Images were displayed for 6seconds each on a computer monitor. Location and time to first fixation, total fixation duration, and total visit count and duration for each type of appliance were measured. Subjects were then asked to complete an online survey. Participants spent the least amount of time looking at the photograph of the control, followed by those of the ceramic brackets, posterior attachments, and anterior and/or posterior attachments. The anterior and/or posterior image had the least number of visits but garnered the longest visit duration (1.32 visits averaging 0.74seconds per visit). This was followed by the images of the posterior attachments (1.40 visits, 0.70seconds per visit), ceramic brackets (1.43 visits, 0.65seconds per visit), and minimal attachments control (1.45 visits, 0.61seconds per visit). The hierarchy of most preferred appliances across all 250 respondents was as follows: minimal attachments control, ceramic brackets, posterior attachments, and anterior and/or posterior attachments. Overall, 88.4% of subjects would compromise appliance esthetics during treatment for a better outcome (n=221). Eye-tracking data show that time to the first fixation was negatively correlated with its survey ranking and that an increase in attachments led to an increase in total fixation duration. There is a general desire for clear aligners without attachments and ceramic brackets over clear aligners with multiple attachments. Survey data suggest that although respondents viewed appliance esthetics as highly important, nearly all would compromise appliance esthetics during treatment if it resulted in a better outcome.

Laboratory Evaluation of IPS-lithium Disilicate Orthodontic Brackets

The purpose of the study is to evaluate the microhardness and light transmission through new Emax brackets with two ceramic brackets commercially available in the markets. The brackets were divided into three groups: (1) E max brackets (IPS E-max press, Ivoclar, Germany), (2) Gemini clear brackets (Unitek, 3M, USA), and (3) discovery pearl ceramic brackets (Dentaurum, Germany). The Vickers hardness test was used to evaluate the hardness of the wings in addition the light transmission of three brackets types were tested through using an orthodontic light cure device and light meter. The hardness test of discovery pearl ceramic brackets and Gemini clear brackets gave significantly higher than E.max one while later gave significantly more light transmission through it when compared with another two brackets. In conclusion, the noticeable tested brackets make E max material one of choice for modern esthetic brackets in future although the hardness is less comparing the other tested brackets due to the purity of material compering with other test brackets which are reinforced of their material, the new material requiring improving of mechanical performances.

Evaluation and Comparison of the Color Stability of Various Esthetic Brackets, When Exposed to Various Food Dyes: An in vitro Study:

Evaluation and Comparison of the Color Stability of Various Esthetic Brackets, When Exposed to Various Food Dyes: An in vitro Study:

Occlusal height difference between maxillary central and lateral incisors: should aesthetic perception influence bracket placement?

BackgroundThe aim of this study was to verify anecdotal evidence that the maxillary central-to-lateral occlusal height difference (OHD) of more than 0.5 mm is a feature displayed in the majority of media and to discuss its implications for individualized orthodontic treatment planning.MethodsPhotographs of smiling female models were collected from a variety of printed advertisements and allocated to 3 groups (n = 30 each): 1 dental, 2 fashion and 3 orthodontics. Group 4 used female patient images from orthodontic textbooks, assuming an OHD of 0.5 mm between maxillary central and lateral incisors. OHD was assessed by measuring the incisor height on the photographs and using average values to establish height differences.ResultsThe average maxillary central-to-lateral incisor OHD differences were 1.39 mm (dental literature), 1.34 mm (fashion advertisements), 1.23 mm (orthodontics) and 0.62 mm (orthodontic textbooks) respectively. The differences between the advertisement groups were not significant (P > 0.05), but for orthodontic textbooks they were (P < 0.001).ConclusionsAdvertisers seem to prefer greater maxillary central-to-lateral OHD compared to commonly used bracket placement protocols. Therefore, discussing OHD at start of treatment is recommended; modification of commonly used bracket placement protocols may be helpful to achieve desired aesthetic outcome.

Do laypersons perceive aesthetic differences between coated and uncoated orthodontic archwires?

ABSTRACTIntroduction: Aesthetic brackets are routinely combined with metallic wires in fixed orthodontic therapy, mainly due to the disadvantages of the clinical use of aesthetic archwires. The current situation needs to be explored in the literature by considering laypersons’ perceptions. Objective: The objective of this cross-sectional study was to evaluate laypersons’ aesthetic perceptions of metal archwires with and without aesthetic coating. Three age ranges and both sexes were evaluated. Methods: A volunteer using fixed aesthetic orthodontic appliance was photographed wearing the following archwires: stainless steel, nickel-titanium (NiTi), NiTi coated with epoxy resin and NiTi coated with rhodium. Using a 100-mm visual analog scale, 90 laypersons evaluated the photographs. Sex and age ranges (18-30, 31-45, over 46 years of age) were evaluated. The comparisons between the archwires and between age ranges were made using ANOVA and Tukey’s test. Genders were compared using Mann-Whitney test. Results: The results showed that the evaluators considered the archwire coated with epoxy resin to be the most aesthetic (60.64 ± 13.04) and the NiTi wire to be the least aesthetic (30.82 ± 7.79) (p< 0.05). Only the range of 31-45 years of age considered the NiTi archwires less aesthetic, when compared with the other age groups. For the other archwires, no statistically significant difference were found between the age groups. No differences between the sexes were detected. Conclusions: The results indicated that the aesthetic coated archwires represent an improvement in the visual aspect of ceramic brackets. The epoxy-coated metal wire was considered the most aesthetic option.

Comparison of torque expression in esthetic brackets.

BackgroundThe objective of this work is to test the null hypothesis that there is no difference in the torque expression among different esthetic brackets.Material and MethodsFive ceramic self-ligating brackets (In-Ovation C – GAC, Damon Clear–Ormco, QuicKlear-Forestadent, Click-It -TP Orthodontics, Clarity SL-3M Unitek) and 4 ceramic conventional brackets (Inspire Ice–Ormco, InVu Ceramic-TP Orthodontics, Ceramic Roth–Morelli, Clarity Metal-Reinforced Ceramic Bracket-3M Unitek) were selected. Metallic Damon MX self-ligating bracket (Ormco) was used as control. Third-order moments were measured at 12º, 24º and 36º using an archwire torsion device associated with a Universal Testing Machine (EMIC DL2000), with 0.019x0.025-inch stainless steel wire. Anova followed by Tukey tests were used for intergroup comparisons.ResultsIn all tested angulations the Damon Clear bracket presented the highest torque expression, followed by Clarity, Clarity SL and Damon Mx brackets, with the worst torque expression shown by the InVu Ceramic bracket. The InVu Ceramic demonstrated the largest while the Damon Clear brackets demonstrated the smallest slot height and clearance.ConclusionsThe null hypothesis was rejected since torque expression was different among the esthetic brackets evaluated. It was also concluded that the slot height is directly related to torque expression. Key words:Torque, orthodontic brackets, orthodontic appliances, incisor, ceramics.

Evaluation of the force generated by gradual deflection of 0.016-inch NiTi and stainless steel orthodontic wires in self-ligating metallic and esthetic brackets

BackgroundThe purpose of this study was to evaluate the deflection forces of 0.016-inch Nitinol and stainless steel orthodontic wires, in association to different self-ligating brackets.Material and MethodsSpecimens were mounted in a clinical simulation model and evaluated in a Universal Testing Machine (INSTRON 3342), using a 10N load cell and ISO 15,841, as a protocol. Eight of these models were prepared, each one for the bonding of each set of self-ligating accessories to be tested: Damon Q, Damon Clear (Ormco), In-Ovation R, In-Ovation C (GAC), BioQuick, QuickClear (Forestadent), SmartClip and Clarity SL (3M). Data were subjected to One-way ANOVA, followed by Tukey tests (P<0.05).ResultsElastic deflection results showed that the deactivation forces increased with increase in wire deflection in the different brackets evaluated. For the different combinations, Clarity SL generated the greatest force and Damon Clear presented the lowest force when compared to the other brackets in all alloys and deflections. BioQuick and QuicKlear were those with the most similar behavior with each other.ConclusionsStrength values increased with gradual increase in wire deflection in all evaluated brackets. Clarity SL generated the greatest and Damon Clear the lowest force when compared to the other brackets in all alloys and deflections tested. Key words:Brackets, orthodontic wires, deflection.

Flash-Free Orthodontic Adhesive System Bonded on CAD/CAM Produced Resin Restorations

Flash-Free Orthodontic Adhesive System represents the latest technology in the field of orthodontics. In the present study the bonding technique is applied on CAD/CAM produced resin crowns. Ten resin blocks were shaped after an upper premolar crown design from the 3Shape Library, and they were divided ino two groups: on Group 1, control, Clarity Advanced braces (3M Unitek, Monrovia, CA, USA) were bonded using XT Adhesive Paste (3M Unitek, Monrovia, CA, USA), while on Groups 2 same aesthetic brackets were applied, using the APC Flash-Free Adhesive Coated Appliance System (3M Unitek, Monrovia, CA, USA). Bracket positioning time was recorded for each sample. Zwick Zoel Z005 testing machine was used to measure the shear bond strength (SBS) at which debonding takes place. Adhesive remnant index (ARI) was registered, as well as presence or absence of adhesive flash and accuracy of flash cleaning before curing. Group 1 showed a mean bonding time of 46.4 s, while Group 2 needed about 20.6 s for each bracket bonding. Mean SBS values for both groups are considered clinically acceptable (6.27 MPa for Group 1 and 7.77 MPa for Group 2). ARI scores were zero for all samples and after debonding, on group 1 can be observed the adhesive flash. In conclusion, APC Flash-Free Coated Appliance System showed reduced time for bracket positioning compared to the conventional technique. APC Flash-Free System showed acceptable SBS values, higher than the uncoated brackets. No composite was left on the resin crown after debonding, the adhesive flash resulted in the conventional technique remaining on the edges of the debonded brackets.

Comparison of the effect of the feldspathic sample surface preparation method on the strength of the bond with orthodontic aesthetic brackets

As the amount of orthodontically treated adults is steadily increasing, the need arose of adhesive cementation of brackets for crowns and other ceramic restorations. The surface of dentist porcelain does not undergo etching with phosphoric acid (H3PO4) and requires a different procedure protocol. &lt;b&gt;Aim.&lt;/b&gt; The aim of the research was to evaluate the strength of the polycrystalline bracket bonds with feldspathic ceramics processed using some selected methods. &lt;b&gt;Material and methods.&lt;/b&gt; Feldspathic ceramic samples fired onto a metal cylinder were divided into five groups and processed with the selected methods. The surface was subjected to scanning electron microscope (SEM) imaging and roughness profile examination. Next, after cementing the polycrystalline brackets and after conducting a thermocycling process (24h, 1450 cycles), a technical shear resistance test was performed in a strength testing machine. The resulting adhesive-cohesive fracture was evaluated as well as the ARI (Adhesive Remnant Index). The findings were subjected to statistical analysis. &lt;b&gt;Results.&lt;/b&gt; All the samples tested demonstrated that the orthodontic bracket bonding strength with ceramics examined using the shear resistance test amounted to more than 7 MPa, with such bonding strength being considered sufficient to conduct orthodontic treatment. The highest mean strength was obtained and the most frequent adhesive-cohesive fracture with damage to the ceramics was observed in group HF (12,85 MPa). The preparation applied in group MEP (10,03 MPa) had the lowest influence on the ceramics structure. This was observed in the roughness profile test and in the SEM test. The surface structure of the samples in the MEP group did not significantly differ from that in the K group. &lt;b&gt;Conclusions.&lt;/b&gt; The tests demonstrated that the alternative procedure methods applied during the feldspathic ceramics surface preparation for adhesive cementing comply with the requirements set by the contemporary orthodontics. &lt;b&gt;(Włodarczyk-Górniak O, Szczesio A, Nowak J, Klimek L, Szczepańska J, Pawłowska E. Comparison of the effect of the feldspathic sample surface preparation method on the strength of the bond with orthodontic aesthetic brackets. Orthod Forum 2018; 14: 167-77).&lt;/b&gt;

Evaluation of the influence of the type of orthodontic bracket on the perception of age

Background: The demand for orthodontic treatment has increased considerably among adult patients. Factors that contribute to this scenario are the use of new technologies, development of new materials and access to information. However, a large number of adults still do not adhere to treatment due to poor aesthetic appearance of brackets. Objective: To assess the influence of the use of metallic or aesthetic brackets on the perception of age. Methods: A 45-year-old female was photographed smiling and the image was manipulated in an editing program in order to generate a smile without brackets or with metallic or aesthetic brackets. A photographic album was assembled in addition to a questionnaire in which the interviewees answered questions about the age of the individual in the three situations. Results: The proportion of respondents who assigned age > 40 years (actual age) was higher in the group that evaluated the image without the orthodontic appliance. The frequency of respondents who indicated ages < 30 and between 30 and 40 years was higher in the groups that evaluated the images with aesthetic and metallic brackets, respectively. The appearance < 30 years of age was positively associated with the use of aesthetic and metallic brackets. The appearance of 30 to 40 years was positively associated with the use of metallic, but not with the use of aesthetic brackets. Conclusions: It was possible to infer that, according to the participants of this study, the use of orthodontic appliance made the individual look younger. There was no significant difference between aesthetic and metallic appliances in contributing to a more youthful appearance corresponding to age < 30 years. The appearance of 30 to 40 years of age was positively associated with the use of metallic brackets, but not with the use of aesthetic brackets.

The shear bond strength of reconditioned sapphire bracket after rebonding with sandblasting zirconia

Introduction: Sapphire bracket is the best aesthetic bracket with metal bracket-like mechanical properties. In conditions causing attachment lost between sapphire bracket and enamel, a rebonding procedure will needed. The shear bond strength of sapphire bracket decrease after the rebonding procedure. Sandblasting, hydrofluoric acid etching, and silanization as surface treatment are widely used to improve the bracket bond strength. The purpose of this study was to evaluate the effect of zirconia as sandblasting material towards the shear bond strength of reconditioned sapphire bracket. Methods: This study was an experimental laboratory with as much as 27 samples of sapphire bracket divided into 3 groups. Group I was rebonded with sandblasting zirconia and silane, group II with hydrofluoric acid etching and silane, and group III with new bracket bonding. The attachment strength measurement indicator was the shear bond strength test and the SEM analysis. Results: The shear bond strength test showed the average value for each group were 12.97 MPa, 9.26 MPa, and 10.58 MPa, consecutively. The test results were then analysed using a one way ANOVA and LSD (p &lt; 0.05), which showed that significant difference only found in the comparison between group I with group II, but not in the comparison between group I with group III. The SEM analysis result showed that sandblasted surface has homogenous microporosities in high quantities. Conclusion: Zirconia as sandblasting material was effective in increasing the shear bond strength of reconditioned sapphire bracket.

Is laser conditioning a valid alternative to conventional etching for aesthetic brackets?

ER:Yag lasers have been described as a more conservative alternative to conventional acid-etching enamel conditioning technique, when bonding conventional metallic orthodontic brackets. Since the use of aesthetic orthodontic brackets is constantly increasing, the purpose of the present report has been to test laser conditioning with different aesthetic brackets. Study Design: Five different aesthetic brackets (microfilled copolymer, glass fiber, sapphire, polyoxymethylene and sintered ceramic) were tested for shear bond strength and Adhesive Remnant Index scores using two different enamel conditioning techniques (acid etching and ER:Yag laser application). Two hundred bovine incisors were extracted, cleaned and embedded in resin. Specimens were then divided into 10 groups with random tables. Half of the specimens were conditioned with conventional orthophosphoric acid gel, the other half with ER:Yag laser. Different aesthetic brackets (microfilled copolymer, glass fiber, sapphire, polyoxymethylene and sintered ceramic) were then bonded to the teeth. Subsequently all groups were tested in shear mode with a Universal Testing Machine. Shear bond strength values and adhesive remnant index scores were recorded. Statistical analysis was performed. When considering conventional acid etching technique, sapphire, polyoxymethylene and sintered ceramic brackets exhibited the highest SBS values. Lowest values were reported for microfilled copolymer and glass fiber appliances. A significant decrease in SBS values after laser conditioning was reported for sapphire, polyoxymethylene and sintered ceramic brackets, whereas no significant difference was reported for microfilled copolymer and glass fiber brackets. Significant differences in ARI scores were also reported. Laser etching can significantly reduce bonding efficacy of sapphire, polyoxymethylene and sintered ceramic brackets.

Trends in Contemporary Orthodontic Research Publications: Evaluation of Three Major Orthodontic Journals

Background In this study, we aimed to evaluate the inclination of orthodontic research published in original articles in three of the most popular and recognized orthodontic journals with high impact factor; American Journal of Orthodontics and Dentofacial Orthopedics (AJODO), the Angle Orthodontist (AO), and European Journal of Orthodontics (EJO) published in a 5-year duration time frame (2010–2014). Materials and Methods Online search with supplementary hand searching was undertaken for original research articles in these three orthodontic journals from 2010 to 2014. Classification of data was completed autonomously by manual and direct appraisal of the manuscript of each journal. Results and Conclusion Three thousand one hundred and forty articles published in AJODO, AO, and EJO in the particular time period were selected, out of which 1783 original research study articles (56.78%) were appraised for classification in their various respective knowledge domains. AO (82.73%) and EJO (76.99%) were relatively more committed toward publication of research work in comparison to AJODO (34.55%). Research articles based on perception and questionnaires (12%), temporary anchorage devices (11%), cone-beam computed tomography (8%), invisible orthodontics (lingual orthodontics, clear aligners, esthetic brackets, and wires) (5%), and airway examination (5%) were the five most recurrently selected subjects of interest (41%) in these three journals during the observation period. The total number of research articles published in the three journals reduced statistically significantly in 2014 when compared to 2010.

Frictional resistance of active and passive aesthetic self-ligating brackets with different orthodontic wire sizes

The purpose of this study was toinvestigate the effect of passive and active Self-ligation of aesthetic brackets on the static and kinetic friction with different wire sizes. Two types of ceramic brackets were used; Empower Clear (active self-ligatingbracket (ASLB)) and Damon Clear 2 (passive self-ligating bracket (PSLB)). They were coupled with 0.017 x 0.025-in and 0.019 x 0.025-in stainless-steel (SS) wires. A universal testing machine was used to pull the brackets along the distal end of the archwire. The test was performed at 5 mm/min crosshead speed over a distance of 8 mm to measure the static friction (SF) and the kinetic friction (KF) under dry conditions. The results showedthe PSLB’s to have significantly lower SF and KF with both wire sizes.

THE SHEAR BOND STRENGTH OF THE AESTHETIC BRACKETS BY USING SELF ETCHING PRIMERS

Background: Aesthetic brackets have considerably less mechanical undercuts than those on a metal mesh base design, and therefore they might be expected to have a greater bond failure rate if they are used without a silane-coupling agent. Aim: This study was designed to evaluate the effect of using Self etching on the shear bond strength of the Aesthetic brackets. Material and methods: This study was carried out on fivety premolar teeth were collected from orthodontic patients attending out-patient orthodontic clinic, faculty of Dental Medicine, Al-Azhar University who will be treated with premolar extraction. The teeth were cleaned with tap-water, brushed and stored in distilled water with 0.1% thymol until use. The collected teeth were divided into two groups, one of them was used in dry condition and the other was used in contaminated condition. Each group was sub divided into two equal subgroups of teeth with uncoated and pre coated ceramic bracket for testing the shear. Descriptive statistics including the mean; standard deviation; minimum and maximum values for the Shear bond strength (SBS) were calculated for each of the 10 test groups. The results of this study showed that New metal-reinforced orthodontic ceramic brackets (Clarity brackets) presented a clinically acceptable shear bond strength value with Transbond Moisture-insensitive primer and Transbond Plus-self etching primer can be used successfully for bonding clarity ceramic brackets (uncoated and pre coated) under dry and salivary contaminated condition. Conclusion: Pre coated ceramic brackets in contaminated condition presented higher self etching primer than uncoated ceramic brackets.