Esthetic Brackets Research Articles

Inhibition of the Growth of Escherichia coli and Staphylococcus aureus Microorganisms in Aesthetic Orthodontic Brackets through the In Situ Synthesis of Ag, TiO2 and Ag/TiO2 Nanoparticles.

Plaque control is especially important during orthodontic treatment because areas of the teeth near brackets and wires are difficult to clean with a toothbrush, resulting in debris buildup of food or dental plaque, thus causing caries and periodontal disease. The objective of this study was to evaluate the antimicrobial properties of silver nanoparticles (AgNPs), titanium dioxide nanoparticles (TiO2NPs), and silver/titanium dioxide nanoparticles (Ag/TiO2NPs), synthesized on the surface of α-alumina ceramic brackets. The AgNPs and TiO2NPs were synthesized by a simple chemical method, and these were characterized by XRD, SEM, and XPS TEM; the antimicrobial activity was tested against Staphylococcus aureus and Escherichia coli by diffusion test. The results of this study demonstrated that by this simple chemical method, silver and titanium dioxide nanoparticles can be synthesized on the surface of α-alumina esthetic brackets, and these NPs possess good antimicrobial activity and the possibility of reducing dental caries, periodontal disease, and white spot generated during orthodontic treatment.

Colour Stability between In-House 3D-Printed Resin Brackets and Conventionally Aesthetic Brackets: An In Vitro Study

Background: To evaluate colour stability in artificial saliva by mechanically simulating brushing between in-house 3D-printed resin brackets (IH3DBs) and commercially available brackets. Methods: The samples consist of four sets of ten aesthetic brackets each supplied by four different manufacturers: clear Damon, Synovate C, Crystal and in-house 3D printed brackets (IH3DBs). The brackets were immersed in a plastic tank containing artificial saliva maintained at a constant temperature of 37 °C with a 65-minute brushing system. Staining changes at T0 (pre-brushing) and T1 (post-brushing) were measured with a spectrophotometer according to the VITA and Master scale and brightness values. Statistical analysis compared the colour changes with the Wilcoxon test and in case of significance, severity was investigated. The significance level considered was p < 0.05. Results: The IH3DBs shows statistically significant differences for both scales and brightness values. The Damon and the Crystal brackets report a statistically significant difference only for brightness. The Synovate C bracket shows no statistically significant differences. Conclusions: The IH3DB produced chromaticity differences for the VITA and Master scale possibly due to the surface roughness created during the printing process. However, the IH3DBs together with Damon Clear improved brightness, due to the mechanical action of brushing.

Correlating Frictional Forces Generated by Different Bracket Types during Sliding and Surface Topography Using Scanning Electron Microscopy and Optical Profilometer.

The study aims to correlate the frictional forces (FF) of four different types of commercially available ceramic brackets to their surface topography. Two monocrystalline (MC) brackets (CLEAR™, Adanta, Germany; Inspire ICE™, Ormco, USA), one polycrystalline (PC) bracket (Symetri Clear™, Ormco, USA), one clear hybrid esthetic bracket (DISCREET™, Adanta, Germany), and a stainless-steel (SS) bracket (Victory™, 3M Unitek, USA) served as control. Both static friction (SF) and kinetic friction (KF) were recorded during sliding using an Instron universal machine in dry settings. The bracket slot surface topography was evaluated. A scanning electron microscope (SEM) and a profilometer machine were used for assessment before and after sliding. Frictional forces values during sliding were as follows in descending order; Inspire ICE™, CLEAR™, DISCREET™, Symetri Clear™, and, lastly, Victory™. Also, DISCREET™ scored the highest in surface roughness (Sa) values followed by Symetri Clear™. None of the correlations were statistically significant. Frictional forces produced during sliding were not always directly related to surface roughness. Monocrystalline ceramic brackets appeared to have the greatest FF and a low surface roughness. Furthermore, DISCREET™ scored a very low frictional value comparable to metal brackets yet showed the highest surface roughness. Metal brackets exhibited the greatest surface smoothness before sliding and the least SF. Predicting the FFs produced during sliding mechanics would help the practitioner while choosing the bracket system to be used, and while planning the treatment mechanics, how much force to deliver, and how much tooth movement to expect. How to cite this article: AlBadr AH, Talic NF. Correlating Frictional Forces Generated by Different Bracket Types during Sliding and Surface Topography Using Scanning Electron Microscopy and Optical Profilometer. J Contemp Dent Pract 2024;25(1):41-51.

Evaluation of frictional forces between aesthetic brackets and archwires in wet conditions (An in-vitro study)

Frictional resistance occurs whenever sliding happens, negatively impacting treatment outcomes and duration. It is a clinical challenge and must be dealt with efficiently to achieve the best orthodontic results. Aims of this study: compare and evaluate the static frictional forces under the wet condition to mimic the oral environment produced by using a polycrystalline ceramic bracket, monocrystalline ceramic bracket, 0.014 of an inch nickel-titanium (Rhodium coated archwires, and ilusio aesthetic archwires), and 0.019 x 0.025 of an inch stainless steel (Rhodium coated archwires, and ilusio aesthetic archwires). Ninety-six aesthetic brackets (48 monocrystalline and 48 polycrystalline brackets) were used and stored in different incubation media (distilled water and acid challenge); each 16 bracket-archwire combinations were tested 6 times by Instron testing machine under wet conditions. Polycrystalline ceramic brackets combined with 0.014-inch NiTi rhodiumcoated archwires produced significantly low mean static frictional force in an acidic environment. Furthermore, no significant mean static frictional forces difference between monocrystalline and polycrystalline ceramic brackets if combined with 0.014 of an inch NiTi ilusio or 0.019 x 0.025 of an inch SS rhodium coated archwires. Conclusion: Coupling polycrystalline ceramic brackets with 0.014 of an inch NiTi rhodium coated rather than ilusio archwires in an acidic environment is advisable. At the same time, it is wise to combine with polycrystalline ceramic brackets the 0.019 x 0.025 of an inch SS ilusio archwires in distilled water rather than to combine with monocrystalline brackets

The Optical Translucency, Opalescence, and Reflectance of Different As-Received Ceramic Brackets: A Spectrophotometer Study

Aim: To determine the difference in the reflected color coordinates and to compare the translucency and opacity of different as-received ceramic brackets using a spectrophotometer. Materials and Methods: Four types of ceramic brackets were investigated in this in vitro study. A total of 72 ceramic brackets were examined using a spectrophotometer. Reflected color coordinates of the labial side of bracket were measured according to the Commission Internationale de l’Eclairage (CIE) color scale. Color difference between brackets was calculated using the equation: Δ E*ab = [(Δ L*)2 + (Δ a*)2 + (Δ b*)2] 1/2. Translucency parameter (TP) and opalescence parameter (OP) were calculated to determine translucency and opacity of the brackets, respectively. Data was collected and analyzed using IBM SPSS V25. The significance level was set at p ≤ .05. One-way ANOVA and post hoc multiple comparison tests were utilized. Results: The range for CIE L* (lightness) was 62.69 to 58.83, for a* (red–green parameter) −0.33 to −2.9 and for b* (yellow–blue parameter) −2.19 to 2.29. All these color co-ordinates were influenced by bracket brand ( p < .05). DISCREET™ showed the highest TP = 16.342 and Symetri™ Clear showed the lowest = 10.823. The OP values ranged between 1.783 and 3.781 and Symetri™ Clear showed the highest OP. Conclusion: Color coordinates, TP, and OP of esthetic brackets investigated with a spectrophotometer were significantly different and influenced by the material microstructure and/or manufacturing process.

A comparison of bond strength and adhesive remnant index of 3D-printed and metal orthodontic brackets attached using different adhesives

Abstract Introduction The aim of this in vitro study was to evaluate the shear bond strength (SBS) and adhesive remnant index (ARI) scores of two different adhesive applications of aesthetic brackets produced from permanent crown material using 3D-printing technology. Methods Sixty maxillary premolar teeth extracted for orthodontic reasons were divided into two main groups according to the type of bracket (metal brackets n=30, 3D-printed brackets n=30) and further divided into two subgroups according to the type of adhesive (flowable composite, Tokuyama SuperLow; non-flowable composite; 3M Transbond XT). SBS and ARI score evaluations were conducted in the experimental and control subgroups (n=15). Statistical analysis was performed by a one-way analysis of variance, a post-hoc test, and Fisher’s exact test. Statistical significance was accepted as P < 0.05. Results The bond strength of the specimens was significantly affected by the type of composite and bracket type (P < 0.001). However, the SBS values were within or above the desired range for orthodontic treatment in all groups. The highest SBS value was obtained in the Metal Bracket-Transbond XT group (15.03 ± 6.66), while the lowest SBS value was observed in the 3D-Printed Bracket-Transbond XT group (7.91 ± 3.07). It was noted that of all materials evaluated, the most common non-enamel-damaging adhesive–cohesive fractures were in 3D-Printed Bracket Tokuyama SuperLow group (n=13). Conclusions It is recommended that 3D-printed orthodontic brackets have sufficient and acceptable SBS levels for clinical applications and bonding using non-flowable adhesives to produce high SBS values and using flowable adhesives generating high ARI scores.

(440) Quality of Life, Including Sexual Life of Orthodontic Appliance Users

Abstract Introduction Orthodontic treatment is closely related to the quality of life, including sexual life. Oral health obliges us to take a holistic approach to sexual health. Regarding the sexuality of orthodontic appliance users, no such studies have been conducted so far. Objective The main goal of the study was to analyze the quality of life, including sexual life of orthodontic appliance users. Methods 922 people over 18 years old who were undergoing orthodontic treatment with fixed appliances or aligners were selected for the study. Data for the study were obtained using two standardized questionnaires: The Satisfaction With Life Scale and The Sexual Satisfaction Questionnaire, a metric and an author’s questionnaire. Results The study group consisted of 922 people, including 718 women and 204 men, aged 20 to 56 years. All subjects were undergoing orthodontic treatment. Among the respondents, both men and women, the treatment process with the use of classic fixed appliances with metal brackets (n = 544) was dominating. Another group of orthodontic appliance users were patients with fixed appliances with aesthetic brackets (ceramic, porcelain, crystal) (n = 194). The patients treated with aligners were found only in the women's group (n = 145). The average orthodontic treatment time ranged from 1 to 1.5 years, however, there were individuals treated for more than 2 years. The mean score of satisfaction with life in the study group was 20.85. The study showed that men achieve statistically significantly higher results than women on the Satisfaction With Life Scale (p <0.00). The mean score of sexual satisfaction in the study group was 31.10. Regarding the selfassessment of sexual satisfaction, a statistically significant difference was noticed between women and men (p <0.001) – men assessed their sexual life higher than women. The relationship between sexual satisfaction and self-esteem in sexual life proved to be closely related. The self-esteem of the respondents was consistent with the results obtained in a standardized questionnaire and the high self-esteem rate was accompanied by high, objectively assessed sexual satisfaction scores. Sexual satisfaction was also strongly correlated with the respondents' attitude to the orthodontic appliances, the level of satisfaction with the relationship, and the frequency of sexual intercourse. The study demonstrated positive correlations of the sexual satisfaction score with the overall quality of life. Conclusions The attitude of the respondents to the orthodontic appliances has an impact on their quality of life, including sexual life. The orthodontic appliances may generate difficulties (the reduction of frequency or discontinuation) in subjects' sexual behavior, such as kissing and oral sex. Orthodontic appliances may also cause injury during sexual intercourse. The lack of reliable information on the relationship between orthodontic treatment and sexuality forces a need to raise awareness among dentists and orthodontic appliance users about the topics related to orthodontic treatment and sexual health. Disclosure No

Effects of Ultrasonic Instrumentation on the Shear Bond Strength of Ceramic Brackets: An In Vitro Study

Aim: Accumulation of plaque during orthodontic treatment makes oral prophylaxis a regular necessity. The use of esthetic brackets has gained popularity, it becomes necessary to assess the consequences of ultrasonic instrumentation during oral prophylaxis on ceramic bracket’s shear bond strength (SBS). Materials and Methods: Fifty-four premolar teeth which were extracted due to therapeutic reasons were divided into six groups with each group containing nine teeth each. Ceramic brackets were bonded onto the labial surfaces using two different adhesive systems (Ormco Enlight and Transbond) and were subjected to ultrasonic scaling at different scaler tip angulations. The samples were then rendered a debonding force in a Universal testing machine and the bond strengths were assessed. Results: In terms of angulation of ultrasonic instrumentation, among the groups bonded with the Ormco Enlight, the 45° angulation group had statistically significant higher bond strength values compared to the 0° angulation group. Among the transbond groups, there was no statistically significant difference in the bond strengths even though the 45° angulation group had slightly higher bond strength value than the 0° angulation group. Conclusion: Supragingival scaling around the bracket base at 0° around the ceramic brackets for 1 min resulted in the reduction of SBS. Therefore, the clinicians should be cautious during plaque removal, avoid performing extended ultrasonic instrumentation at the bracket base, especially at 0° angulation.

Comparative Study of Transmission of 2940 nm Wavelength in Six Different Aesthetic Orthodontic Brackets.

Previous studies have confirmed the superiority of using erbium lasers (2940, 2780 nm) over other lasers in the debonding of ceramic brackets due to their safety and effectiveness. The most important factor in the debonding of aesthetic brackets is the transmission of the erbium laser through the aesthetic bracket to the adhesive resin. To identify the transmission of the 2940 nm wavelength through different types of aesthetic brackets. A total of 60 aesthetic brackets were divided into six equal groups (10 monocrystalline sapphire brackets-Radiance, AO; 10 monocrystalline sapphire brackets-Absolute, Star Dentech; 10 polycrystalline brackets-20/40, AO; 10 polycrystalline brackets-3M Unitek Gemini Clear Ceramic; 10 silicon brackets-Silkon Plus, AO; 10 composite brackets-Orthoflex, OrthoTech). The aesthetic brackets were mounted in a Fourier transform infrared spectrophotometer (FTIR IRPrestige-21, SHIMADZU) following the typical spectroscopy lab procedure for such samples. The transmission ratio for the 2940 nm wavelength was obtained using IRsolution software. The mean transmission values of the tested groups were compared using a one-way analysis of variance (ANOVA) test followed by a Bonferroni test (post-hoc test). The highest transmission ratio was observed for the Radiance sapphire brackets (64.75%) and the lowest was observed for the 3M polycrystalline brackets (40.48%). The differences among the Aesthetic brackets were significant (p < 0.05). The thick polycrystalline and composite brackets have the lowest transmissibility, whereas the monocrystalline sapphire brackets have the highest transmissibility for the 2940 nm wavelength, meaning that there is a higher possibility of debonding them with a hard tissue laser through thermal ablation.

Comparative assessment of frictional forces between differently designed esthetic brackets during simulated canine retraction.

To evaluate force loss due to friction (FR) with an emphasis on esthetic brackets and their design differences during simulated canine retraction. The tested brackets were round and sharp-cornered conventional-ligating brackets and round-cornered self-ligating brackets. The tested archwires were stainless steel (0.018 × 0.025″ and 0.019 × 0.025″, and 0.018″) archwires. Atotal of 90bracket-archwire combinations in 9equally-sized groups (n = 10) were analyzed. Canine retraction was experimentally simulated in abiomechanical set-up utilizing the custom-made orthodontic measurement and simulation system (OMSS) using aNiTi coil spring that delivered aconstant force of 1 N. The simulated retraction path was up to 4 mm. FR was compared among groups using the Welch t‑test. Significance level(α) was set to 0.05. The round-cornered conventional-ligating bracket exhibited the least FR (28.6 ± 5.4%), while there were no significant differences in FR between the round-cornered conventional-ligating bracket and the round-cornered self-ligating bracket with 0.018″ stainless steel wires. However, the round-cornered self-ligating bracket exhibited the least FR (34.9 ± 5.1% and 39.3 ± 4.6%) with 0.018 × 0.025″ and 0.019 × 0.025″ stainless steel archwires, respectively. The sharp-cornered conventional-ligating bracket showed the highest FR of 72.4 ± 3.0% among the bracket systems tested in this study. The round-cornered conventional-ligating bracket showed less FR when compared to sharp-cornered conventional-ligating bracket. Conversely, the round-cornered conventional-ligating bracket exhibited greater FR when compared to the round-cornered self-ligating bracket, with an exception with respect to the 0.018″ wire. In general, FR increased with increased wire dimension.

Color Stability of Various Plastic and Ceramic Brackets: An In Vitro Study

Introduction: The aim of this study was to evaluate color stability of various plastic and ceramic brackets after immersing in food solutions. Methods: Three plastic brackets and six ceramic brackets brands (three polycrystalline and three monocrystalline brackets) were selected. Ten brackets per brand were immersed in three dye solutions (red wine, coffee and curry). After immersing for one day, three days and seven days, color changes of the brackets were measured using a spectrophotometer (SpectrolinoTM). Color change, ΔE* was calculated based on the CIE L*, a* and b* system. Results: Plastic brackets, especially Silkon MTM showed the biggest color change in red wine, coffee and curry. 20/40TM bracket showed similar color change with plastic brackets despite that it is a polycrystalline bracket. Other polycrystalline brackets, ClarityTM advanced and VitrineTM, showed smaller color change than plastic but bigger than monocrystalline brackets. Monocrystalline brackets, RadianceTM and Inspire ICETM showed the smallest color change in all three solutions. Conclusions: Significant color change of esthetic brackets can occur based on the bracket composition, dye solution type and immersion time.

Effect of Volatile Oils on De-Bonding of Polycarbonate Bracket Reinforced with Ceramic Filler: A Quantitative Study (Part 1)

Introduction: The introduction of esthetic brackets is a new clinical approach in the field of orthodontics. Two main types of esthetic brackets have been developed and became widely available; the polycarbonate brackets, and the ceramic brackets. Both types have faced two significant de-bonding problems: (1) enamel and bracket fracture. The two problems have been well documented and continue to be of concern to clinicians.&#x0D; Aim: The aim of this in vitro study was to evaluate quantitatively the effect of three volatile oils and their combinations on the de-bonding of ceramic brackets. &#x0D; Material and Method: Polycarbonate brackets reinforced with ceramic filler were bonded to one hundred and eighty (180) sound extracted human premolars using Transbond XT light curing adhesive. The teeth were then distributed into the following groups according to the type of volatile oil and period of application: clove oil (5 &amp; 30 minutes), peppermint oil (5 &amp; 30 minutes), Black seed volatile oil (5 &amp; 30 minutes), and mixture of peppermint + Black seed volatile oils (5 &amp; 30 minutes) in addition to control group. The brackets were then de-bonded using the Instron Universal Testing Machine and the de-bonding force was recorded for each type of the volatile oils in different times of application. &#x0D; Result: The result revealed that the Black seed volatile oil gave the lowest de-bonding force in 5 minutes and 30 minutes of application whereas the mixture of the Black seed oil + peppermint oils gave the highest force in both time of application. Further, the peppermint oil application for 5-minute was found to be in the second rank whereas the Clove oil was in the third rank. Furthermore, in the 30 minutes of application the Clove oil was in the second rank whereas the peppermint was found to be in the third rank and the combination of Black seed oil + peppermint oil shows the highest debonding force.&#x0D; Conclusion: Despite the limitation of the present study result, an assumption has been drawn from the results obtained that (1) the 5- minutes of black seed or peppermint volatile oils application can be considered the best debonding agent compared to the other volatile oils; (2) the clove oil can be used after de-bonding to facilitate the final cleansing-up of enamel surface. To confirm the latter assumption, further investigations are needed.

Comparative in vitro analysis of the sliding resistance of a modern 3D-printed polymer bracket in combination with different archwire types.

ObjectivesTo analyse the sliding resistance of a modern 3D-printed polymer bracket combined with different archwire types and to compare the results with conventionally used polymeric, ceramic and metal brackets. It was of further interest which bracket-archwire combination could be best qualified for clinical use.Materials and methodsThe sliding behaviour was tested using an orthodontic measurement and simulation system (OMSS) for the use of two bracket types of the polymer, ceramic and metal group in combination with a 0.016 inch × 0.022 inch and 0.017 inch × 0.025 inch archwire of nickel-titanium (NiTi), titanium-molybdenum alloy (TMA) and stainless steel. Six bracket types were combined with six different archwire types and compared to each other.ResultsThe sliding resistance showed significant differences between various the bracket-archwire complexes. The combination of 3D-printed polymer brackets with both steel archwire cross-sections showed the least values of sliding resistance (average 23–29%), while the combination of ceramic brackets with TMA archwires presented the highest (average 47%).ConclusionsThe present study could show that modern 3D-printed bracket materials can have similar or even better mechanical properties than conventional ones regarding sliding resistance. Although the combination of bracket and archwire material is decisive for low sliding resistance values, the selection of the bracket material seems to have a greater influence than the selection of the archwire material or its cross section.Clinical relevanceIt might be possible in future to combine aesthetic and biomechanical requirements for aesthetic brackets by using 3D-printing technology.

TAD Assisted Retraction in A Lingual Appliance for Correction of Dentoalveolar Class II Malocclusion

ABSTRACT&#x0D; Orthodontics, in today’s contemporary world, is focused mainly on aesthetics. Most of the adult patients are reluctant to orthodontic treatment due to their un-aesthetic appearance. To answer such problems several options are available, ranging from aesthetic brackets, made from tooth-coloured plastic or ceramic, another option is Invisalign, which is restricted to the treatment of only certain kinds of simple malocclusions. Hence, the lingual appliance selected for this case is by far the best option available from the aesthetic outlook and mechanical aspect however torque control of anterior teeth in lingual orthodontic appliance has always been considered a major problem. For maintaining the torque value of anterior teeth either we have to apply direct moment and force to the lingual brackets or by using a different combination of lever-arm and mini-screws mechanics to deliver force in a line that passes through or near to the center of resistance. In the present case, we utilized the combination of long lever-arm and palatal mini-implant system to produce a controlled en-masse retraction of the anterior teeth. This customised long lever arm created by soldering one power to others such that the point of force application is close the center of resistance.

Effect of cigarette smoke on aesthetic brackets: an in vitro study.

ABSTRACTObjective: The objective of this study was to evaluate the effect of cigarette smoke (CS) on physical and mechanical properties of ceramic, polycarbonate and alumina ceramic brackets. The null hypothesis tested was that aesthetic brackets would not be influenced by CS. Methods: Ninety aesthetic brackets were allocated to three groups (n = 30): ceramic (GCE), polycarbonate (GCO) and alumina ceramic (GPS). Ten samples of each group were assigned to color and surface roughness analysis, performed before (T0) and after (T1) exposure to CS; and twenty samples were allocated into control and experimental groups (n = 10) (not exposed and exposed to CS, respectively) for shear bond strength test (SBS). Exposure to CS followed an adaptation of the method described by Le Mesurier. Colorimetric reading, surface morphology and roughness, SBS and adhesive remnant index (ARI) were assessed. Statistical analysis comprised independent and paired t-tests, ANOVA/Tukey and Fisher’s exact tests (α = 0.05). Results: Changes were observed in brackets’ color (NBS: GCE = 2.4; GCO = 1.9; GPS = 2.1), surface roughness (ΔRa: GCE = 1.1 ± 0.8 µm; GCO = 1.9 ± 1.5µm; GPS = -0.3 ± 0.1 µm / ΔRz: GCE = 1.4 ± 1.0 nm; GPS = -0.5 ± 0.1 nm); and SBS (GPS - experimental = 221.8 ± 48.6 N) after exposure to CS (p< 0.05). Conclusions: Exposure, in vitro, of aesthetic brackets to CS resulted in changes of color to darker and more opaque shades, surface roughness alterations, and higher SBS values. ARI scores were not associated with exposure to CS.

Frictional Resistance of Non Coated and Epoxy Coated Superelastic NiTi Wires used for Aligning in Three Types of Brackets

Introduction: Coated archwires are preferred in combination with aesthetic orthodontic brackets by orthodontists over non metallic aesthetic archwires. Studies evaluating the frictional properties of epoxy coated round superelastic Nickel Titanium (NiTi) archwires are limited to stainless steel brackets. Aim: To evaluate and compare the frictional resistance of an epoxy coated 0.016" superelastic NiTi archwire in stainless steel, composite and ceramic brackets and to compare it with the frictional resistance generated by non coated 0.016" superelastic NiTi archwire in same brackets. Materials and Methods: An in-vitro experimental study was conducted in the Department of Orthodontics at SRM Dental College from January to February 2020. Frictional resistance of 30 epoxy coated aesthetic 0.016" upper superelastic NiTi wires (G4™ Nickel Titanium, 0.016, Upper Trueform™ I, ToothColored) and 30 conventional 0.016" upper superelastic NiTi wires (G4™ Nickel Titanium, 0.016, Upper Trueform™) from G&amp;H® orthodontics while sliding across three different types of brackets were evaluated. Twenty stainless-steel (Gemini® 3M unitek, Monrovia, California), 20 composite (FLI® RMO, Denver, Colo.), and 20 gemini clear ceramic (Gemini clear ® 3M unitek, Monrovia, California) 0.022x0.028" Slot Roth prescription maxillary first premolar brackets were used. The brackets and archwires were divided into six groups of different bracket and archwire combination with 10 samples in each. An Instron testing machine with a 10 N tension was used to measure the frictional resistance. The obtained values were analysed using One-way ANOVA and followed by Post Hoc Tukey HSD for multiple comparison. Results: Coated wires generated significantly high friction in ceramic brackets (136.90±3.79 gms) followed by composite brackets (125.66±3.44 gms) and stainless steel brackets (92.53±8.70 gms). Non non coated wires generated significantly high friction with ceramic brackets (89.60±2.90 gms) whereas the friction generated in composite (70.87±5.79 gms) and stainless steel brackets (67.70±2.80 gms) was not significantly different. Conclusion: Epoxy coating increased the frictional resistance generated by the 0.016 superelastic NiTi archwires irrespective of bracket materials. The coated wires generated less friction in composite brackets compared to ceramic brackets. Further clinical trial are recommended to evaluate the aligning efficacy of these archwires in aesthetic brackets.

Comparison of Frictional Resistance of Different Esthetic Archwires in Different Esthetic Brackets in Dry and Wet Fields: An in vitro Study

Introduction: The patient's desire toward achieving an esthetically pleasing face has not only increased the demand for orthodontic therapy but also necessitates the need for an esthetic appearance during the treatment period which led to the introduction of tooth-colored ceramic brackets and archwires. Materials and Methods: The experimental research was done using esthetic brackets (polycrystalline ceramic brackets with and without metal slot and monocrystalline brackets) and stainless steel archwires (uncoated, Teflon coated, epoxy coated, and rhodium coated) in both dry and wet fields. Two typhodont models were selected onto which the above-mentioned brackets were bonded and frictional resistance was evaluated using Instron machine for each of the archwire-bracket combinations in dry and wet fields. Results: The uncoated stainless steel (SS) wires showed less friction when compared to esthetic-coated SS wires. The frictional resistance was least for wet field when compared with dry field for all the groups and subgroups. It was also found that frictional resistance was minimum for Teflon-coated wires in polycrystalline ceramic bracket with metal slot (wet field) and maximum for rhodium-coated wires in monocrystalline brackets (dry field). Conclusion: Polytetrafluorethylene/Teflon-coated archwire and ceramic bracket with metal slot could be preferred as the esthetic archwire and bracket material of choice, respectively, due to their low frictional properties.

Morphometric evaluation of the slot of aesthetic orthodontic brackets.

Introduction: : Dental malocclusion is a public health problem and orthodontics is the specialty in charge of diagnosing and treating it, aesthetic brackets are an alternative, the costs are varied, which makes its precision doubtful. Objective: Evaluate the measurement and geometry of the slot of three brands of aesthetic brackets and verify their precision. Material and Methods: Twenty-four aesthetic Roth prescription 0.022” slot polycrystalline ceramic brackets were evaluated in three brands: American Orthodontics (United States), Morelli (Brazil) and Class One (China). Eight samples were measured per group in a specialized laboratory certified in measurement and calibration, the measurements of internal and external height were verified, per mesial and distal; and the parallelism of the slot of each bracket. The results were processed with SPSS 22 and tests of variance (ANOVA), Tukey and Student's t were used. Results: The measurements of the brackets' grooves do not correspond to the measurements announced by the manufacturers, these are greater, however, American Orthodontics is within the tolerance range (p&lt;0.01); the slots in the mesio-distal direction and the lingual vestibule are not parallel in Morelli and Class One. Conclusion: The results of this study indicate that the slots of the supports are oversized, their geometry is not precise and varies greatly between brands and prices. The three-dimensional control of the tooth could be compromised.

Comparison of friction of metallic and ceramic brackets during sliding mechanics after prophylaxis with sodium bicarbonate jet: An in vitro study

An in vitro experimental study was carried out with the objective to compare the friction in aesthetic and metallic brackets after prophylaxis with sodium bicarbonate jet during sliding mechanics. Aesthetic monocrystalline (n=24) and polycrystalline (n=24) and metallic brackets (n=24) were used. Each group of brackets was divided into two groups, as follows: the first group received prophylaxis with a bicarbonate jet, while the second group did not. An acrylic plate was attached to the base fixature of the Instron 4411 universal testing machine, simulating the retraction movement of the canine during sliding mechanics. The bracket was pulled at a speed of 0.5mm/minute over a distance of 0.5mm. The data were analysed by analysis of variance (ANOVA) and Tukey test. After the sodium bicarbonate jet, conventional metal brackets showed less friction (P<0.05). While the aesthetic brackets did not show significant difference in friction between the exposed and non-exposed groups with the sodium bicarbonate jet (P>0.05), the polycrystalline brackets showed greater friction when compared to the other groups of brackets. It was concluded that prophylaxis with sodium bicarbonate jet did not influence the resistance to friction in aesthetic brackets; however, metal brackets showed a significant decrease in friction after prophylaxis with sodium bicarbonate jet. Our results suggest that the abrasion of the sodium bicarbonate particles can cause micromorphological changes, which may influence the friction; however, studies with scanning electron microscopy are necessary.

Evaluation of torque moment in esthetic brackets from bendable alloy wires.

To examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb]) wires. This study examined ceramic (CR), zirconium oxide (ZC), polycarbonate (PC), and conventional metallic brackets (MT) (upper, 0.018-inch and 0.022-inch slots) combined with SS, Ti-Mo, and Ti-Nb wires using elastic module ligation. The torque moments delivered by various wire and bracket combinations were measured using a torque gauge apparatus. The wire torque angles at 5-40° were examined. The torque value increased in the order of CR, ZC, MT, and PC brackets for both 0.018-inch and 0.022-inch slots. The fracture points of the CR and ZC brackets combined with SS and Ti-Mo wires were approximately more than 30° and 35°, respectively. No fracture points were detected in the combination of ZC brackets and Ti-Nb wires. The current study identified the material characteristics of CR, ZR, and PC brackets during torque tooth movements. The present results demonstrate a characteristic combined effect between different esthetic brackets and bendable alloy wires.