Ceramic Self-ligating Brackets Research Articles

A comparative evaluation of the antimicrobial efficacy of Chlorhexidine and Chlorine dioxide on self-ligating brackets contaminated with Streptococcus mutans biofilm- An In vitro study

ObjectiveTo evaluate and compare antimicrobial efficacy of Chlorhexidine and Chlorine dioxide mouthwashes on S.mutans biofilm created on metal and ceramic self-ligating brackets. Materials and methodsA total of 162 metal and ceramic self-ligating brackets (3M™ SmartClip™ & Clarity SL™) were randomly divided into 3 groups and 2 subgroups. Standard procedures were followed to coat all brackets with S.mutans biofilm. The biofilms were cultivated which were then subjected to the effects of the mouthwashes. Quantitative assessment was carried out by comparing the number of viable colonies of S.mutans. A Mann-Whitney U test was used to compare the data between the experimental and control groups. (p < 0.05). ResultWhen compared to untreated controls the antimicrobial efficacy of Chlorhexidine Digluconate and Chlorine Dioxide mouthwashes was found to be statistically significant (p = 0.00). The comparison between Chlorhexidine digluconate and Chlorine dioxide mouthwashes was not statistically significant in Ceramic self-ligating group (p = 0.502) and statistically significant in Metal self-ligating group (p = 0.001) ConclusionS mutans colonies on metal and ceramic self-ligating brackets can be reduced effectively by Chlorhexidine digluconate and Chlorine dioxide mouthwashes. Chlorhexidine digluconate more effective for metal bracket group. Both mouthwashes had comparable antimicrobial effectiveness, with the difference in the number of viable colonies following exposure for ceramic bracket groups.

Evaluation of the frictional resistance between different bracket types, archwires and ligation materials: An in-vitro study

In orthodontic treatment, brackets need to slide along the archwire to allow for alignment of the teeth. The lesser the friction between the bracket and the archwire, the easier it is to align the teeth and the lighter the forces required to make such movements. In recent years, patients’ esthetic demands have driven the field of orthodontics to find alternatives to conventional stainless steel bracket systems. While ceramic brackets meet the esthetic demands, their inferior frictional characteristics have always been an issue for orthodontists.The present in-vitro research study evaluates and compares the frictional resistance between various types of brackets, archwire materials and ligation methods. The purpose of the study was to equate the frictional resistance among 12 different groups using the universal testing machine, so as to recognize the factors involved in the in-vitro appraisal of resistance to sliding (RS) and inferring their clinical implications. In this study, 120 pre-adjusted edgewise upper central incisor brackets with MBT 0.022″ slot were used, which included 40 standard metal brackets, 40 ceramic brackets, 20 self-ligating metal brackets and 20 self-ligating ceramic brackets. 0.019″ x 0.025″ SS (stainless steel) archwires, esthetic archwires, Teflon-coated ligatures and conventional elastic modules to ligate the archwire to the brackets except in self-ligating brackets, were used. The average frictional resistance of Group A10 was the minimum succeeded by A9, A12, A4, A11, A8, A3, A7, A2, A6, A1 and A5. In the comparison of the mean frictional resistance of 12 different groups, the ANOVA test showed noticeably different frictional resistance amongst the groups (F=745.80, P&amp;#60; 0.001). Self-ligating metal bracket combinations with different archwires showed a significantly smaller magnitude of friction than self-ligating ceramic, metal and ceramic bracket combinations. Teflon-coated ligature combinations possess less friction in comparison with conventional elastomeric module combinations.

Evaluation of the Failure Rate and Clinical Efficacy of Orthodontic Brackets Indirect Bonding with Computer-Aided Transfer Jig System: An In Vivo Study

This study aimed to evaluate the failure rates and relevant factors of bonded orthodontic brackets with a computer-aided design and manufacturing (CAD/CAM)-based 3D-printed indirect bonding jig system (IDBS) using 2531 natural teeth selected from 99 orthodontic patients. Ceramic self-ligating brackets and metal tubes were used in this study. Proportion analysis was used to calculate the total bracket re-bonding rate and respective proportions of bonding failure and position error. Crossover frequency analysis was used to analyze the total bracket re-bonding, bonding failure, and position error rates in different tooth positions of the maxilla and mandible. Multiple linear regression analysis was used to evaluate the association between dependent variables (age, sex, treatment stage, skeletal divergence, and tooth position) and the bracket bonding failure rate. Pearson’s Chi-square test was used to test the difference between the maxilla and mandible for each variable. The total bracket re-bonding rate was 22.64%, and the bonding failure rate and position error rates accounted for 15.09% and 7.55%, respectively. The bonding failure rate was higher in the mandibular teeth than in the maxillary teeth (p &lt; 0.05). Anterior teeth had a higher position error rate, and mandibular anterior teeth had a higher bonding failure rate. The accuracy of IDBS was higher in the premolars and molars. Sex, age, and treatment stage were affected by IDBS. Patients with hyperdivergent skeletal patterns had higher rates of bracket bonding failure. The results of this study can provide practical guidelines for placing brackets with 3D-printed IDBS on the entire dentition to ensure the precision and accuracy of their use during orthodontic treatments.

Comparison of the sliding resistance between three models of self-ligating ceramic brackets: An in vitro and micro-morphological study

The main objective of our study was to compare a new model of self-ligating ceramic bracket (Clarity™ Ultra by 3M™), to its competitors by evaluating their resistance to sliding during an in vitro simulation of canine retraction. The sample consisted of 120 brackets (30 brackets in each group: Victory Twin Series LP™, Clarity Ultra™ by 3M™, Damon Clear 2™ by Ormco™ and Empower™ 2 Clear by American Orthodontics™). Canine retraction was simulated using a universal testing machine connected to a software that measured the average sliding resistance (ASR) for each group. Five brackets from each group were randomly selected and observed under a digital optical microscope at ×50 magnification. ANOVA test and Tukey's analysis were carried to detect statistically significant differences between the groups' sliding resistance values, at the risk of α=0.05. Measured ASR values of control group (metallic Victory Twin) were the highest ones (70.55g), followed by 3M™ (33.22g) then Damon™ (6.72g) and AO™ (5.49g) (P-value<0.0001). Through microscopic observations, we found that the 3M™ bracket has the lowest percentage of slot chamfering (8%) compared to the other brackets (12%). The 3M™ bracket also has the widest slot followed by AO, and then Damon™. All three bracket types have oversized slots compared to the manufacturer's description, the least oversized being the 3M™ bracket, followed by AO™ and then Damon™. 3M™ and Damon™ brackets have covers that concealed the entire wire in the vertical dimension whereas the AO™ bracket has a curvilinear cover that only shields the gingival part of its slot. Wire-play is zero for the 3M™ group, and 0.1mm for the other two groups. Clarity Ultra™ ceramic bracket produced by 3M™ does not perform well against friction forces compared to its competitors and that is due to its micro-morphological characteristics.

Reducing Friction in Orthodontic Brackets: A Matter of Material or Type of Ligation Selection? In-Vitro Comparative Study.

(1) Background: Orthodontic appliances have changed and improved with the increasing demand for orthodontic treatment of the general population. Patients desire for shorter orthodontic treatments and for the wearing of more aesthetic devices has led to the technological development of orthodontic brackets; these were manufactured from aesthetic materials (ceramics, composite polymers) and presented different designs regarding the way archwires are ligated to the bracket. The aim of this study was to determine whether there were any differences between the static frictional forces generated by stainless steel (metallic) and polycrystalline alumina (ceramics) conventional and self-ligating brackets. (2) Methods: Static friction assessment was carried out in vitro with a universal testing machine, HV-500N-S (Schmidt Control Instruments, Hans Schmidt & Co. GmbH), intended for measuring compression and traction forces. (3) Results: The study revealed significant differences in static frictional forces at the bracket-archwire interface between the tested brackets. Stainless steel brackets produced lower static friction forces than polycrystalline alumina and self-ligating brackets generally produced lower static frictional forces than conventional brackets. The reduction of frictional forces was noticeable in the first stages of treatment, when thin, flexible orthodontic archwires (0.016” NiTi) are used. Engaged with large rectangular stainless steel archwires, (0.019 × 0.025” SS), the frictional forces produced by conventional and self-ligating metal brackets were similar, no significant differences being observed between the two types of metallic design. However, in the case of tested ceramic brackets, the results showed that the self-ligating type allows a reduction in frictional forces even in advanced stages of treatment compared to conventionally ligation. (4) Conclusions: From the perspective of an orthodontic system with low frictional forces, metal brackets are preferable to aesthetic ones, and self-ligating ceramic brackets are preferable to conventional ceramic brackets.

Influence of orthodontic brackets and permanent retainers on the diagnostic image quality of MRI scans: A preliminary study.

Orthodontic treatment with fixed mechanotherapy using appliances and permanent retainers bonded after treatment is a routine procedure performed in clinical dentistry. Patients with braces or retainers sometimes need to undergo magnetic resonance imaging (MRI) for various reasons. Radiologists do not know the exact impact of the materials used in orthodontics on the diagnostic image quality of MRI scans. The aim of the study was to evaluate the influence of different types of orthodontic brackets and permanent retainers on the diagnostic image quality of MRI scans. Twenty patients with bonded brackets (stainless steel buccal/labial, stainless steel lingual, ceramic self-ligating with metal slots, ceramic, and polycarbonate) and 18 patients with bonded fixed retainers (titanium, fiber-reinforced composite, multi-stranded stainless steel, and different combinations of permanent retainers) participated in the study. The same adhesive was used for bonding. Cranial MRI scans of 6 regions were acquired for each subject, using a 1.5T MAGNETOM machine. Six radiologists evaluated the images and provided scores based on the modified receiver operating characteristic (ROC) analysis of distortion. The paired Wilcoxon signed-rank test was used to assess differences between the materials and the anatomic sites with regard to the distortion rating scale. Cohen's kappa coefficient (κ) was applied to establish the interrater reliability. A statistically significant difference was found between stainless steel brackets (both buccal/ labial and lingual) and all other experimental materials in terms of mean distortion scores (p = 0.020 or p = 0.024). The interrater reliability proved to be high. Stainless steel buccal/labial and lingual brackets caused maximum distortion of the images, which became non-diagnostic; hence, such brackets should be removed before MRI. Ceramic and polycarbonate brackets as well as fiber-reinforced composite retainers did not distort the images; thus, they need not be removed. Ceramic self-ligating brackets with metal slots, titanium retainers, multi-stranded stainless steel retainers, and combinations of fixed retainers caused minimal distortion; however, the images were still diagnostic. Hence, patients using these materials may not need to have them removed before MRI.

A Comparison of Shear Bond Strength Values of Recycled Self-Ligating Ceramic Brackets with a New Ones (An-in Vitro Study)

Background: The aim of the current study was to assess the effects of different recyclrd procedures on shearbond strength and morphological characteristics of deboned mechanically retaining self-ligating ceramicbrackets’ bases, then compare the results with the new brackets of the same company.Material and Methods: Forty-eight mechanical retentive self-ligating ceramic brackets from Damon®ClearTM company were used, thirty-six of these brackets were bonded to non-etched and slightly dampbuccal tooth surface in order to permit an easy debonding of these brackets by dental tweezer, these debondedbrackets were then allocated into three experimental groups (12 per group): recycled by sandblasting,recycled via an Er, Cr: YSGG laser irradiation, and recycled by flame. After recycled, twelve new brackets(the control) plus the previously thirty six reconditioned brackets were bonded to the forty-eight premolarteeth following standardized bonding procedure.Results: There were highly significant differences in the mean shear bond strength values among all groupsusing analysis of variance F-test; in addition, the mean shear bond strength of new brackets had the highestmean value of 22.90 Mpa, followed by Er,Cr:YSGG laser group 20.29 Mpa, then sandblasted group of 11.42Mpa, while flame group had the lowest mean shear bond strength value of 7.63 Mpa; furthermore, the resultsshowed a significant difference in adhesive remnant index (ARI) among all groups.Conclusion: all recyclrd procedures would result in a clinically acceptable shear bond strength value. TheEr,Cr:YSGG recyclrd procedure can effectively eradicate the adhesive from the bases of ceramic bracketswithout jeopardizing them; thus, this technique can be preferred over other recyclrd procedures.

Comparison of Shear Bond Strengths and Fiction Forces Among Various Self-ligating Ceramic Brackets

Purpose: Ceramic self-ligating brackets were developed recently, however, only few comparative studies had been reported about their bond strengths and friction. The aim of the study was to compare shear bond strengths and friction forces of various self-ligating ceramic brackets. Materials and methods: The present study is divided into two parts. In shear bond strength test, bovine teeth were used as a substitute for human teeth. Five groups of brackets (three ceramic self-ligating brackets including ClippyC, GeniusCrystal, DamonClear2, ClarityAdvanced (conventional ceramic bracket), Damon3MX (metal self-ligating bracket), were used and debonded with 12 brackets in each group. The shear bond strengths and adhesive remnant index (ARI) scores were compared. In the friction test, several parameters were investigated, including five kinds of bracket, two wire sizes (0.014" Cu-NiTi and 0.016" × 0.022" NiTi) and three angulations (0°, 5°, and 10°). Each bracket/wire/angulation combination was tested five times in 30 settings. A total of 150 runs were performed.

Effects of a ceramic active self-ligating bracket on retraction/tipping/rotation of canine, premolar mesialization, and transverse arch dimensions: A preliminary single-blind split-mouth randomized clinical trial

There is no clinical study on ceramic self-ligating brackets (SLBs). Therefore, this preliminary study was conducted for the first time to address its effects. This split-mouth randomized trial was performed on 32 quadrants in 16 orthodontic patients needing extraction of maxillary premolars and distalization of canines. In each blinded patient, right/left sides were randomized into control (ceramic bracket) and experimental (ceramic SLB) groups. Dental stone models were taken before canine retraction and 3 months into retraction. Models were digitized as three-dimensional models. Changes were measured on superimposed models. Groups were compared using Wilcoxon signed-rank test (α = 0.05, β = 0.1). Both bracket types caused significant changes after 3 months in terms of all assessed clinical outcomes (P ≤ 0.002). Compared to conventional ceramic brackets (control), ceramic SLBs reduced retraction rate (P = 0.001), canine rotation (P = 0.001), canine tipping (P = 0.002), and arch expansion at the canine site (P = 0.003). However, the extents of anchorage loss (P = 0.796) and arch constriction in the premolar area (P = 0.605) were not statistically different between the bracket types. Compared to conventional metal-lined ceramic brackets, active ceramic SLB can increase the duration of canine distalization, while reducing canine rotation and tipping (inducing more bodily movements). The loss of anchorage with ceramic SLB was similar to that of conventional ceramic bracket after 3 months of treatment (considering the lower rate of SLB canine retraction during that time). Both brackets similarly constricted the arch at the premolar site. In the canine area, they expanded the arch, with the SLB causing smaller extents of expansion.

Surface Roughness on the Slots and Wings of Various Ceramic Self-Ligating Brackets and their Potential Concern on Biofilm Formation.

The surface roughness of various orthodontic materials could affect biofilm formation and friction. The purpose of this study was to examine the surface roughness and chemical composition of the slots and wings of several ceramic self-ligating brackets. Four types of ceramic self-ligating brackets were separated into experimental groups (DC, EC, IC, and QK) while a metal self-ligating bracket (EM) was used as the control group. Atomic force microscopy and energy-dispersive x-ray spectroscope were used to examine the surface roughness and chemical composition of each bracket slot and wing. The control group was made of ferrum and chrome while all the experimental groups were comprised of aluminum and oxide. There was a statistically significant difference in the roughness average (Sa) among the various self-ligating brackets (p< 0.001 in slots and p<0.01 in the wing). The slots in the EC group had the lowest Sa, followed by the DC, IC, control, and QK groups. The wings in the IC group had the lowest Sa, followed by the EC, DC, control, and QK groups. There is a significant difference in the surface roughness of the slots and wings among several types of ceramic self-ligating brackets.

AVALIAÇÃO DAS PROPRIEDADES MECÂNICAS DE FIOS E BRAQUETES ORTODÔNTICOS ESTÉTICOS

Objetivo: comparar as forças de deflexão nos fios ortodônticos estéticos em braquetes autoligáveis cerâmicos passivos e interativos. Métodos: Quatro corpos de prova foram montados em um modelo de simulação clínica e avaliados em uma Máquina de Ensaio Universal (Emic). Em uma placa de resina acrílica foram fixados 10 dispositivos, onde foram colados os braquetes, simulando o arco dentário superior em forma de parábola. O dispositivo de acrílico representante do incisivo central direito foi movimentado em ativações de 0 a 3 mm, com velocidade constante de 0,5 mm/min. Testes de Análise de Variância e de Tukey, com significância de 5% (P

Comparative Evaluation of Frictional Resistance of Three Different Types of Passive Self-ligating Ceramic Brackets Using Coated and Uncoated Stainless Steel and Nickel Titanium Arch Wires: An In Vitro Study

Comparative Evaluation of Frictional Resistance of Three Different Types of Passive Self-ligating Ceramic Brackets Using Coated and Uncoated Stainless Steel and Nickel Titanium Arch Wires: An In Vitro Study

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.

Load-deflection characteristics of coated and noncoated nickel-titanium wires in self-ligating brackets using a modified bending test: An in vitro study

To determine and compare the force-deflection values of different types of nickel-titanium (NiTi) wires during unloading phase at varying deflections, that is 1 mm, 1.5 mm, 2 mm, and 2.5 mm, with the use of self-ligating ceramic brackets using modified bending test on a typodont under controlled temperature conditions. In this in vitro study total of 45 wires of ovoid shape of three different NiTi wires - pseudoelastic NiTi (Group I), heat activated NiTi (Group II), and esthetic coated NiTi (Group III) for maxillary arch were tested after insertion in ceramic self-ligating brackets bonded to plastic teeth of phantom jaw. The maxillary left lateral incisor was removed to simulate a malpositioned tooth which acted as the load site, and load-deflection characteristics were measured during unloading using Instron, and data analyzed statically by two-way analysis of variance, Tukey's post hoc test, intraclass correlation coefficient and Pearson correlation coefficient. A two-sided (α = 2) P < 0.05 was considered statistically significant. When wires were compared at each deflection statistically significant difference was observed between the three groups of wires (Group I > Group II > Group III) at all the four levels of deflection except for Group II versus Group III at 1 mm, 1.5 mm, and 2 mm of deflection. Statistically significant difference was noted in mean load values for comparisons made at different deflections for each wire except for the comparison made at 1.5 versus 2 mm for Group II and Group III. Overall comparison showed esthetic coated Ni-Ti wires gave significantly lower mean load values, followed by heat activated and pseudoelastic NiTi wires. Thus, heat activated NiTi wires are best suited in patients with severe malpositions/periodontitis, while for esthetically conscious patients esthetic coated NiTi can be used.

Surface analysis of metal clips of ceramic self-ligating brackets.

ObjectiveThe aim of this study was to analyze the surface composition, roughness, and relative friction of metal clips from various ceramic self-ligating brackets.MethodsSix kinds of brackets were examined. The control group (mC) consisted of interactive metal self-ligating brackets while the experimental group (CC, EC, MA, QK, and WA) consisted of interactive ceramic self-ligating brackets. Atomic force microscopy-lateral force microscopy and scanning electron microscopy-energy-dispersive X-ray spectroscopy were used to analyze the surface of each bracket clip.ResultsAll the clips in the experimental groups were coated with rhodium except for the QK clip. The results showed that the QK clip had the lowest average roughness on the outer surface, followed by the MA, EC, WA, and CC clips. However, the CC clip had the lowest average roughness on the inner surface, followed by the QK, WA, MA, and EC clips. The QK clip also had the lowest relative friction on the outer surface, followed by the MA, EC, CC, and WA clips. Likewise, the CC clip had the lowest relative friction on the inner surface, followed by the QK, WA, MA, and EC clips.ConclusionsThe surface roughness and relative friction of the rhodium-coated clips were generally higher than those of the uncoated clips.

Intrapulpal Temperature Increases Caused by 445-nm Diode Laser-Assisted Debonding of Self-Ligating Ceramic Brackets During Simulated Pulpal Fluid Circulation.

This study investigated temperature increases in dental pulp resulting from laser-assisted debonding of ceramic brackets using a 445-nm diode laser. Eighteen ceramic brackets were bonded in standardized manner to 18 caries-free human third molars. Pulpal fluid circulation was simulated by pumping distilled water at 37°C through the pulp chamber. The brackets were irradiated with a 445-nm diode laser. Temperatures were measured using a thermal camera at points P1 (center of the pulp) and P2 (in the hard dental tissue) at the baseline (T0), at the start and end of laser application (T1 and T2), and the maximum during the sequence (Tmax). Significant differences in the temperatures measured at P1 and P2 were observed among T0, T1, T2, and Tmax. Significant increases in temperature were noted at points P1 and P2, between T1 and T2, T1 and Tmax, and T2 and Tmax. The maximum P2 values were significantly higher than at P1. The maximum temperature increase measured in the pulp was 2.23°C, lower than the critical threshold of 5.5°C. On the basis of the laser settings used, there is no risk to the vitality of dental pulp during laser-assisted debonding of ceramic brackets with a 445-nm diode laser.

Frictional Resistance in Various Ceramic Brackets using Archwires of different Alloys, Sizes and Cross sections: A Comparative Study

Introduction: Friction at the bracket-archwire interface has been observed as one of the most important factors affecting tooth movement. Hence it is importance to assess the friction generated during tooth movement to bring about optimal treatment results.Objective: To compare the frictional resistance of various ceramic brackets using different archwires, and to compare the static and kinetic frictional force of various ceramic brackets using different archwires.Materials &amp; Method: The present study evaluated and compared the friction generated at the bracket archwire interface when 0.018” and 0.019”x0.025” stainless steel archwires and 0.019”x0.025” teflon coated stainless steel archwires were moved through conventionally ligated, passive self-ligating and interactive self-ligating ceramic brackets. The static and kinetic frictional forces were also evaluated and compared.Result: Highly significant differences in kinetic (p&lt;0.001) and static (p&lt;0.001) frictional forces were observed in all three groups when used with the different archwires. On comparing the static and kinetic frictional forces significant differences were observed among all three groups (p&lt;0.05).Conclusion: The passive self-ligating brackets produce the least frictional forces when compared to interactive self-ligating and conventionally ligated brackets. Also, the static frictional forces were found to be more as compared to kinetic frictional forces.Orthodontic Journal of Nepal, Vol. 6 No. 1, June 2016, pp.18-22

Air-powder polishing on self-ligating brackets after clinical use: effects on debris levels.

ABSTRACTIntroduction: Debris buildup on brackets and arch surfaces is one of the main factors that can influence the intensity of friction between bracket and orthodontic wire. Objective: This study sought to evaluate the effect of air-powder polishing cleaning on debris levels of self-ligating ceramic brackets at the end of orthodontic treatment, compared to the behavior of conventional brackets. Methods: Debris levels were evaluated in metal conventional orthodontic brackets (n = 42) and ceramic self-ligating brackets (n = 42) on canines and premolars, arranged in pairs. There were brackets with and without air-powder polishing. At the end of orthodontic treatment, a hemiarch served as control and the contralateral hemiarch underwent prophylaxis with air-powder polishing. Debris buildup in bracket slots was assessed through images, and Wilcoxon test was used to analyze the results. Results: The median debris levels were statistically lower in the conventional metal brackets compared to self-ligating ones (p = 0.02), regarding brackets not submitted to air-powder polishing. Polishing significantly reduced debris buildup to zero in both systems, without differences between groups. Conclusions: Ceramic self-ligating brackets have a higher debris buildup in comparison to conventional metal brackets in vivo, but prophylaxis with sodium bicarbonate jet was effective in reducing debris levels in self-ligating and also in conventional brackets.

Ceramic brackets and low friction : A possible synergy in patients requiring multiple MRI scanning.

To investigate any advantages of low friction biomechanics in orthodontic patients with fixed appliances without producing metal artifacts during magnetic resonance imaging (MRI). Frictional resistance generated by bracket-wire-ligature systems was analyzed via an experimental model that reproduced upper canine misalignment. Each sample was tested 10 consecutive times in a dry state; a total of 160 tests were carried out. We documented the frictional forces generated by a 0.012- and 0.014-inch superelastic nickel-titanium wire (SENT) with ceramic self-ligating brackets (SLB) with metal insert and ceramic monocrystalline brackets with nonconventional elastic ligatures (NCEL) in conjunction with various degrees of canine misalignment (1.5, 3.0, 4.5, and 6.0mm). Comparisons between the frictional forces released by the two different bracket-wire-ligature systems were made by conducting 3-way analysis of variance (ANOVA) with Tukey HSD pairwise test (P<0.005). We observed no clinically relevant difference between the frictional forces released by ceramic SLB and ceramic brackets in conjunction with a 0.012- and 0.014-inch SENT. Statistically significant differences were apparent with a 0.012-inch SENT at 4.5 and 6.0mm of canine misalignment, where the SLB revealed higher frictional forces. Ceramic brackets with NCEL revealed frictional forces similar to those generated in conjunction with ceramic SLB, thereby helping to avoid metal artifacts in case of expected necessary MRI during orthodontic treatment with fixed appliances.

Dimensional accuracy of ceramic self-ligating brackets and estimates of theoretical torsional play.

To ascertain the dimensional accuracies of some commonly used ceramic self-ligation brackets and the amount of torsional play in various bracket-archwire combinations. Four types of 0.022-inch slot ceramic self-ligating brackets (upper right central incisor), three types of 0.018-inch ceramic self-ligating brackets (upper right central incisor), and three types of rectangular archwires (0.016 × 0.022-inch beta-titanium [TMA] (Ormco, Orange, Calif), 0.016 × 0.022-inch stainless steel [SS] (Ortho Technology, Tampa, Fla), and 0.019 × 0.025-inch SS (Ortho Technology)) were measured using a stereomicroscope to determine slot widths and wire cross-sectional dimensions. The mean acquired dimensions of the brackets and wires were applied to an equation devised by Meling to estimate torsional play angle (γ). In all bracket systems, the slot tops were significantly wider than the slot bases (P < .001), yielding a divergent slot profile. Clarity-SLs (3M Unitek, Monrovia, Calif) showed the greatest divergence among the 0.022-inch brackets, and Clippy-Cs (Tomy, Futaba, Fukushima, Japan) among the 0.018-inch brackets. The Damon Clear (Ormco) bracket had the smallest dimensional error (0.542%), whereas the 0.022-inch Empower Clear (American Orthodontics, Sheboygan, Wis) bracket had the largest (3.585%). The largest amount of theoretical play is observed using the Empower Clear (American Orthodontics) 0.022-inch bracket combined with the 0.016 × 0.022-inch TMA wire (Ormco), whereas the least amount occurs using the 0.018 Clippy-C (Tomy) combined with 0.016 × 0.022-inch SS wire (Ortho Technology).