Types Of Archwires Research Articles

Assessment of Mutans Streptococci Adhesion on Different Esthetic Coatings of Nickel-Titanium (Niti) Archwires: An In Vitro Study

Plaque and enamel demineralization can occur when orthodontic archwires are present in the oral cavity because they provide a unique surface for bacterial adhesion. Bacterial biofilm plays a major role in the development of complications such dental caries and periodontal disease. The purpose of the study was to examine the effect that an esthetic surface coating of NiTi archwires would have on the adherence of mutans streptococci. Material and method: three types of coated NiTi archwires (rhodium, gold and flexy blue) and one uncoated NiTi archwire with round cross section 0.016 inch were tested in the current study. Five pieces of each types of archwire were incubated in phosphate-buffered saline for two hours. Then, these wire segments were immersed for 5, 90, and 180 minutes with mutans streptococci suspension to conduct the bacterial adhesion assay. Result: there were statistically significant differences in the degree to which bacteria adhered to the various archwires at each time interval, with the level of adhesion being statistically highest on the uncoated NiTi wire and the level being statistically lowest on the gold-coated NiTi wire (p < 0.05). The result showed that the highest bacterial adhesion in 180 min followed by 90 min and the lowest in 5 min. A positive correlation was detected between bacterial adhesion and incubation time. Conclusion: the esthetic surface coating were influence the biofilm adhesion on the archwires, gold coated significantly decrease mutans streptococci adhesion when compare with uncoated NiTi wire. Higher incubation time increased the number of bacterial adherence for all types of archwires.

Alignment Efficiency of Two Archwires in Adolescents with Moderate to Severe Crowding

There is no consensus in clinical orthodontics on which aligning arch wire should be used at the initial stage of treatment. This randomized clinical trial evaluated the efficiency of multistranded Nitinol (Supercable) aligning arch-wire versus a standard arch-wire (Nitinol) in the first stage of orthodontic treatment in adolescents with severe crowding. Forty patients ages 12 to 17 with an Irregularity Index as proposed by Little between 5 to 17 mm were selected. Vinyl polysiloxane impressions (VPS) were taken before treatment (T1) at 6 weeks (T2) and 12 weeks (T3). Roth prescription .022 x .028 Edgewise brackets were bonded using light cure adhesive to the six anterior teeth of each dental arch and bands were placed on all first molars. Subjects were paired by gender and Irregularity Index into two groups of 20 each and assigned either to the control group (Nitinol) or the experimental archwire (Supercable). The predictor variables in this study were the type of archwire, type of dental arch and the time intervals. The outcome variable was the Irregularity Index score. The Irregularity Index was measured using 3D digital study models (e-models) and GeoDigm software from the VPS impressions taken at T1, T2 and T3. The data was analyzed with both a Two and Three-way Analysis of Variance (p≤0.05) to identify differences in the alignment of the maxillary and mandibular teeth and to determine differences between the two archwires. The Two and Three way ANOVA showed that there was a statistically significant difference (p≤0.05) in the alignment capabilities between the maxilla and the mandible. However, there was no evidence of a statistically significant difference (p=0.301) between NiTi and Supercable archwires at any time interval.

Comparison of surface roughness and hardness of three different brands of esthetic coated NiTi archwires: invitro study

BackgroundThe purpose of the current in vitro study was to evaluate the surface roughness and hardness of three brands of as-received esthetic coated NiTi archwires and compare them with the same parameters after immersion in artificial saliva.MethodsThree groups of 0.016 × 0.022 inch epoxy-coated NiTi orthodontic wires [Tooth tone coated NiTi (Ortho Technology, West Columbia, USA), EverWhite NiTi (American Orthodontics, Wisconsin, USA) and Nitanium Super Elastic Tooth Tone Plastic coated (Ortho Organizers, San Marcos, CA, USA)] were compared. Each group was subdivided into five as-received archwire specimens and five archwire specimens retrieved following immersion in artificial saliva for 28 days. Atomic force microscopy was used for analysis of average surface roughness (Sa). Hardness testing was performed using Digital Vickers hardness tester. ANOVA and Kruskal-Wallis tests were used for comparing the wire groups.ResultsThe ranking of (Sa) values was as follows: Nitanium Ortho Organizers > Everwhite American Orthodontics > Tooth tone Ortho Technology (P > 0.05). Nitanium Ortho Organizers archwires showed significantly greater (Sa) than both other groups following immersion in saliva (P < 0.001). The coating hardness of as-received and post-immersion archwires from Tooth tone Ortho Technology was significantly lower than the other groups (P < 0.001). For all the three types of archwires, the mean hardness of immersed wires was significantly lower than that of the as-received archwires (P < 0.001).ConclusionsEsthetic coated archwires have shown unpleasant surface changes following exposure to artificial saliva. These surface changes are affected by physical characteristics such as surface roughness and hardness of the coating.

Evaluation of the effect of different toothpastes on the frictional resistance of aesthetic archwires: an in vitro study

there has been a trend for using aesthetic orthodontic treatment by many patients recently. The aim of this study was to evaluate the brushing effect of three brands of toothpaste on the frictional resistance of two brands of aesthetic archwires (in wet conditions). in this study, two brands of fully coated aesthetic archwires, Teflon-coated and Epoxy-coated archwires, were utilized in the study. Forty segments from the straight ends of each archwire were cut (total of 80 wires), inserted into ceramic brackets and ligated with the conventional figure "O" elastomeric ligatures (bonded on CNC blocks). Every ten pieces for each type of aesthetic archwire were brushed for one minute daily for thirty days with three types of toothpaste (Ortho. Kin, GUMOrtho and LACALUT White &amp; Repair) and distilled water (except ten pieces for each type of aesthetic archwire were brushed only with distilled water and without toothpaste). These CNC blocks were tested using an Instron Tinius Olsen machine with distilled water. The tests used for statistical analysis were an Independent t-test and an ANOVA test at a 0.05 level of significance. The study showed no significant difference in static and kinetic frictional resistance between the coated archwire and the kinds of toothpaste. The orthodontists can use either Epoxy or Teflon-coated archwires for patients undergoing orthodontic treatment (working stage) who are using either type of toothpaste (Ortho. Kin, GUMOrtho or LACALUT White &amp; Repair) for maintenance of oral hygiene. Keywords: Aesthetic archwires, Friction, Toothpaste

The in vitro biomechanics of anterior arch expansion using fixed lingual appliances with coil springs or archwire stops.

The presented study investigates differences in the biomechanics of straight and mushroom fixed lingual appliances when implementing coil springs and stops for anterior arch expansion. An in vitro orthodontic simulator was used to measure three-dimensional forces and moments on each tooth of a simulated maxillary arch. Mushroom and straight archwire forms of 0.016″ NiTi round archwire were considered, using 0.010″ × 0.030″ NiTi open coils and 0.016″-0.018″ archwire stops (n= 44 per group). Teeth in the anterior dental arch were moved from a neutral to crowded position to replicate anterior crowding of central and lateral incisors. Forces and moments of interest for lateral incisors and first premolars were compared using repeated measures mixed multivariate analysis of variance (α= 0.05). Three comparisons between straight versus mushroom archwires and two comparisons of coil springs vs. stops were not statistically significant. Overall, it was found that the use of a straight lingual archwire produced larger differences in forces and moments between using stops and coil springs than when using a mushroom archwire. Using stops produced larger forces and moments for both types of archwires as compared to using coil springs. The largest expansion forces were produced using straight archwires with stops, exceeding 3.0N of force. Straight archwires with coil springs produced the lowest expansion forces on lateral incisors, just exceeding 1.5N. The findings of this study have elucidated significant differences in the biomechanics of transverse arch expansion using straight or mushroom fixed lingual appliances with coil springs or stops.

Metal Release and Cytotoxicity of Different Orthodontic Bracket-Wire Combinations: An In Vitro Study.

To quantify and compare the metal ions released from different bracket-wire combinations and to assess their cytotoxicity. A total of 360 fabricated sectional fixed orthodontic appliances were divided into 6 groups. The first three groups consisted of stainless-steel brackets with stainless-steel, snickel-titanium (NiTi), and titanium-molybdenum alloy (TMA) archwires, and the other three groups were fabricated using ceramic brackets (polycrystalline alumina) with stainless-steel, NiTi, and TMA archwires. These appliances were immersed in artificial saliva (pH 6.5 ± 0.5, 37°C), for 1 week, 2 weeks, and 1 month. The nickel and chromium ions released in the artificial saliva were quantified using a flame atomic absorption spectrometer, and cytotoxicity assessment was performed using a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay on human cervical cancer cell line. The stainless-steel bracket groups displayed a significantly greater release of nickel and chromium ions compared to the ceramic bracket groups (P < 0.05). However, no significant differences were identified when comparing the three archwire types within the stainless-steel/ceramic bracket groups. At the end of 1 month, the % cell viability demonstrated by the appliances was in the decreasing order of stainless-steel-TMA > ceramic-stainless steel > stainless-steel-NiTi > ceramic-NiTi > stainless-steel-stainless steel > ceramic-TMA. Considerably greater release of nickel and chromium ions was observed from the appliances utilizing stainless-steel brackets compared to those employing ceramic brackets. However, no remarkable difference in the levels of nickel and chromium ions was observed when comparing the three archwires: stainless steel, NiTi, and TMA. In the cytotoxicity assessment, the ceramic-TMA combination displayed the highest level of cytotoxicity, while the stainless-steel-TMA combination displayed the least cytotoxicity.

An in vitro comparative evaluation of surface roughness characteristics of different orthodontic archwires: An atomic force microscopy study.

Background. The present study evaluated and compared the surface roughness (SR) of five different types of orthodontic archwires made by two different manufacturers. Methods. In this in vitro study, 10 samples of five different archwires comprising of three types of shape memory wires, SmartArch (Ormco), Damon (Ormco), Heat-activated NiTi (HANT) (G&H Orthodontics), Stainless Steel wire (SS) (Ormco), and conventional NiTi (G&H Orthodontics) were examined by atomic force microscopy (AFM). The processing of 3D images was carried out using Gwyddion software, from which the root mean square (rms), the roughness average (Ra), and the maximum height (mh) of the scanned surface profile were documented. The data were analyzed with one-way ANOVA followed by post hoc Tukey tests for intergroup comparisons. Results. The mean SR of SS wires was the least (Ra=8.70±0.17), followed by NiTi wires (10.29±2.00) with a significant difference between them (P<0.05). Among the three shape-memory wires, the HANT wires had the least SR (Ra=22.97±16.56) compared to SmartArch wires (Ra=25.55±3.78) and Damon wires (Ra=25.67±4.54), but the difference was not significant (P>0.05). Conclusion. The SS wires by Ormco had the least SR followed by G&H orthodontics NiTi wires. The three different shape-memory wires tested had no significant difference in SR values.

Nickel Release and the Viability of Streptococcus mutans Corresponding to Low Risk of Dental Caries in Artificial Saliva Containing Orthodontic Appliances: In Vitro Study.

The aims of this study were to determine the effect of different levels of Streptococcus mutans that correspond to a low risk of dental caries on nickel release and to determine the viability of S. mutans. Simulated fixed orthodontic appliances composed of copper nickel titanium, nickel titanium, or stainless steel were immersed in Klimek artificial saliva for 10 days with or without S. mutans inoculation on day 7. Same levels of S. mutans cultures (4 × 104 cfu/mL) were inoculated into the artificial saliva without orthodontic appliances. Nickel release was detected by inductively coupled plasma mass spectrometry. The archwire surface was analyzed by atomic force microscopy and scanning electron microscopy. The density of S. mutans significantly increased in the artificial saliva without orthodontic appliances (P < .05). Appliances with nickel titanium alloys showed higher nickel release in the artificial saliva with or without S. mutans than those with copper nickel titanium or stainless steel archwires (P < .05). However, S. mutans increased nickel release only in orthodontic appliances with stainless steel archwires (P < .05). Although atomic force microscopy showed that the surface of as-received stainless steel archwires was smoother than that of nickel titanium or nickel titanium archwires, S. mutans increased the surface roughness of only the SS archwires. S. mutans adhered to all archwire types. While corrosion or corrosion-related processes may have decreased the growth capacity of S. mutans, reciprocally, S. mutans influenced corrosion. Rough surfaces can also promote corrosion; therefore, the surface roughness of metal alloy orthodontic appliances should be evaluated to determine their corrosion behavior.

EVALUATION AND COMPARISON OF LOAD DEFLECTION RATE OF FOUR INITIAL ORTHODONTIC ARCH WIRES: AN IN VITRO STUDY

Aim: The aim of this study was to evaluate the load-deflection rate of four different types of archwires used in initial stage of orthodontic treatment.&#x0D; Materials and methods: A modified three-point bending test was performed on the sample of 60 wires of superelastic Nickel Titanium(NiTi), everwhite esthetic NiTi, thermal NiTi and multistranded coaxial stainless steel (15 each). The load exerted by each of the wire was measured at the deflections of 2 mm and 4mm, subsequent unloading process at 37°C temperature.&#x0D; Results: Comparison of mean load-deflection values revealed that thermal NiTi wires had lowest value at both 2 and 4mm deflection when compared to other three wires which was statistically significant(p=0.009). Superelastic and esthetic NiTi showed similar values of load deflection ratios at both the deflections where as co-axial wire showed 1.89N at 2mm and 5.22N at 4mm deflection.&#x0D; Conclusion: The heat-activated NiTi wires are acceptable in severe crowding and periodontally compromised patients. Multistranded co-axial wire is acceptable when we need minimal alignment; whereas esthetic NiTi wires can replace superelastic Niti based on patient’s need.

Evaluating the Elemental Composition, Transformation Behavior, Crystalline Structure, and Mechanical Properties of Three 0.016-Inch by 0.022-Inch Nickel-Titanium Archwires: An In Vitro Study.

BackgroundNickel-titanium (NiTi) archwires are considered the most attractive wires during the first stage of orthodontic treatment because of their unique properties throughout several generations. This study aimed to evaluate three different NiTi wires in terms of their elemental composition, transformation behavior, crystalline structure, and mechanical properties.Materials and methodsThe study used three different groups of NiTi archwires with dimensions of 0.016 x 0.022-inch (American Orthodontics®, Sheboygan, WI, USA). The first group included six superelastic NiTi archwires (NT3-SE®), with normal force and a stable structure that was not affected by temperature changes. The second group included six heat-activated NiTi archwires activated at 25°C (Thermal Ti-D®), with moderate force and a sensitive structure to thermal changes, especially at room temperature. The third group included six heat-activated NiTi archwires activated at 35°C (Thermal Ti-Lite®), with light force and a sensitive structure to thermal changes, especially at body temperature. X-ray fluorescence (XRF) was performed to determine wire element composition, whereas differential scanning calorimetry (DSC) was performed to determine the austenite finish temperature (Af). The X-ray diffraction (XRD) analysis was used to identify the crystalline structure at room temperature, and a three-point bending test was carried out under constant temperature (37°C) with respect to the instructions of ISO15841/DIS to evaluate the mechanical properties of these wires.ResultsThe XRF analysis revealed that the superelastic NiTi archwires (NT3-SE) were composed of NiTi and chrome, whereas the heat-activated wires (Thermal Ti-D and Thermal Ti-Lite) were composed of NiTi and copper. The DSC showed the Af was at +16.84°C for the superelastic type (NT3-SE), +23°C for the heat-activated at 25°C (Thermal Ti-D), and +33.99°C for the heat-activated at 35°C (Thermal Ti-Lite). The XRD analysis identified the crystalline structure at room temperature for the superelastic type (NT3-SE) as austenite, while for thermal types (Thermal Ti-D and Thermal Ti-Lite) were a compound structure of austenite and martensite phase. Finally, the bending test showed that the highest forces were delivered from the superelastic type (NT3-SE), followed by heat-activated at 25°C (Thermal Ti-D), while the lowest forces were delivered from heat-activated at 35°C (Thermal Ti-Lite). There was no significant difference between the superelastic type (NT3-SE) and thermally activated type at 25°C (Thermal Ti-D), while there was a significant difference between the two previous types and the thermally activated type at 35°C (Thermal Ti-Lite) for all studied unloading points.ConclusionsThe thermal types of archwires (Thermal Ti-D and Thermal Ti-Lite) had lower unloading values in comparison with the superelastic type (NT3-SE). The elemental composition was different between the superelastic wires and the thermal ones. The superelastic wires were also different from the other two types in terms of crystalline structure. The three types of archwires had an activation degree located in the range of oral cavity variations.

Biofilm and Orthodontic Materials: literature reviews and Scanning Electron Microscopy (SEM) images gallery

Plaque control remains a concern in oral health but also in orthodontics. The aim of this paper was to investigate the dental plaque adhesion to different orthodontic appliances. Four literature reviews were initiated to clarify the accumulation of dental plaque to different orthodontic appliances, namely the type of brackets (conventional versus self-ligating, metal versus clear), the type of ligatures (metal versus elastomeric) in addition to the type of archwires. Moreover, a gallery of Scanning Electron Microscopy (SEM) images was made on different orthodontic appliances before and/or after time in the oral cavity. Considering the strong methodological heterogeneity of the included studies, there is no consensus on which type of bracket should be preferred for the prevention of plaque retention. Metal ligatures would be less prone to plaque accumulation compared to elastomeric ligatures, which are themselves color-dependent. The type of archwire was not investigated in this topic. SEM images highlighted the presence of anfractuosities on the surface of new orthodontic archwires as well as the presence of biofilm at different degrees of maturation on the appliances after time in the oral cavity. Although it is not possible to establish a consensus on which orthodontic appliances should be preferred to decrease plaque retention, different stages of biofilm evolution are observable on their surface and therefore potentially associated with a proportional virulence.

Esthetics of Orthodontic Appliances: Objective Evaluation by Spectrophotometry vs Subjective Evaluation Using the Visual Analog Scale Method

In this study, we quantified the color of brackets and archwire appliances for an objective evaluation and investigated its relationship with subjective esthetic evaluation. Five types of commercially available brackets (ceramic brackets C1, C2, and C3; plastic brackets P1 and P2) and three types of archwires (coated nickel-titanium archwires W1, W2, and W3) were used. The reflectance (%) and color (lightness: L*, hue: a*, b*) of each sample were quantified using a spectrophotometer (n = 5). Fifteen combinations of brackets and archwires were used. The esthetic evaluation was performed using the visual analog scale (VAS) method, and responses were obtained from 30 laypersons and 15 orthodontists. The mean VAS score was calculated, and the relationship between the reflectance and color of the bracket and archwire was discussed. The reflectance and L* of the brackets showed significantly higher values for C3 and C1 than for the others and lower values for P1 and P2. The reflectance and L* of the archwire showed significant differences among all samples. There was a high positive correlation between the reflectance and L*. There were statistically significant positive correlations between the layperson and orthodontist groups, between the VAS score and reflectivity, and between VAS score and L*. Our results showed that as the lightness and reflectance of the brackets and archwires increased, the subjective evaluation concerning their esthetic value was higher. It is extremely difficult to evaluate esthetics despite the fact that patients' demands for esthetics have been increasing in recent years. If a method for evaluating esthetics is established, it should help in the development and selection of esthetic devices. The results of this study will facilitate the development of future study designs.

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.

Evaluating the Effect of Different Mouthwashes on the Titanium and Nickel Ions Released from Ordinary and Blue NiTi Archwires (An In-vitro Study)

Objectives: This studywas carried out to evaluate the effect of alcohol present in mouthwash on the Ni and Ti ions release from ordinary andblue NiTiarchwire.Materials and Methods: Sixty specimens of 2cm length from 0.017×0.025 inch maxillary Flexy and Blue Flexy NiTi archwire (30 per each archwires) were immersed in 15 ml. distilled water, alcoholic and alcohol-free Corsodyl mouthwashes (10 per immersing media for each archwire) for one and half hour. After that, Ni and Ti ions released in mouthwashes and distilled waterwere measured using atomic absorption spectrophotometer. Unpaired sample t-test and one way ANOVA test were used for comparison between the archwire types and among different immersion media.Results: Regarding Ni ion, the release of this ion washigher significantly in distilled water followed by alcohol-free Chlorhexidine while the least amount released in alcoholic Chlorhexidine. For Ti ion, the higher amount of Ti ion was released significantly from alcoholic Chlorhexidine followed by alcoholfree Chlorhexidine and the least amount was released in distilled waterin both types of archwires.Both ions were released significantly more from conventional NiTi archwire in all mouthwashes.Conclusions: Ions released from the tested archwires appear to be low with blue NiTi archwire. Ni ion was released more with alcohol-free mouthwash and just the opposite forTiion.

Change in crown inclination accompanying initial tooth alignment with round archwires.

ABSTRACTObjective: To evaluate, in-vitro, the change in crown inclination that occurs during orthodontic leveling and alignment using different archwire-bracket-ligation combinations. Materials and Methods: Four archwire types were tested: (1) 0.012-in stainless steel and (2) 0.0155-in stainless steel multi-stranded, (3) 0.012-in nitinol Orthonol® and (4) 0.012-in nitinol Thermalloy®. Combinations with five types of 0.022-in slot orthodontic brackets were tested: SmartClipTM and Time3® self-ligating brackets, Mini-Taurus® and Victory SeriesTM conventional brackets, and Synergy® conventional-low friction bracket. Conventional brackets were ligated with both stainless steel and elastomeric ligatures. The simulated malocclusion comprised 2.0mm gingival and 2.0mm labial displacements of a maxillary right central incisor. Rotation around the Y-axis (representing labio-palatal inclination) was measured for the different archwire-bracket-ligation combinations. Results: The largest rotation was measured whith Orthonol® and Thermalloy® wires when combined with SmartClipTM brackets (8.07±0.24º and 8.06±0.26º, respectively) and with Synergy® brackets ligated with stainless steel ligatures (8.03±0.49º and 8.0±0.37º, respectively). The lower rotation was recorded when Thermalloy®, multi-stranded, and Orthonol® wires were ligated with elastomeric rings to Mini-Taurus® brackets (1.53±0.18º, 1.65± 0.23º and 1.70±0.28º, respectively) and to Victory SeriesTM brackets (1.68± 0.78º, 2.92± 1.40º and 1.74±0.46º, respectively). Conclusions: All archwire-bracket-ligation combinations produced lingual crown inclination; however, lower changes were observed when the conventional brackets were ligated with elastomeric rings. The multi-stranded archwire produced less rotation with nearly every bracket-ligation combination, compared to the other archwires. The effect of the archwire-bracket-ligation combination on tooth inclination during leveling and alignment should be considered during planning treatment mechanics.

Orthodontic treatment for crowded teeth in children.

Orthodontic treatment for crowded teeth in children.

Qualitative and Quantitative Evaluation of Different Types of Orthodontic Brackets and Archwires by Optical Microscopy and X-ray Fluorescence Spectroscopy

The wear behaviour and chemical composition of orthodontic components influence the mechanical characteristics of a fixed orthodontic treatment. The purpose of this paper is to evaluate the surface alterations of different types of brackets (aesthetic, metallic, and conventional self-ligating) and archwires (superelastic and thermal) subjected to wear tests through optical microscopy and, subsequently, to identify the chemical elements of accessories by X-ray fluorescence. The cycles (5000 for each bracket and 10,000 for each wire) of the tribological test were carried out in dry conditions inside a machine that allows alternating sliding. The results of the study highlighted different wear behaviours even within the same type of brackets and archwires. The monocrystalline sapphire brackets maintain their aesthetic properties despite traces of wear inside the slots and contain minimal amounts of nickel. Superelastic NiTi archwires have a better overall rating than thermal wires, as they do not show significant surface wear alterations.

Addendum

An Ethical Approval Statement or Statement of Informed Consent should have been included for the articles listed below. Their corresponding statements are presented following the article information: Khakhar PG, Daigavane P, Kamble R, Niranjane P, Dargahwala H, Bidwai P. Evaluation and Comparison of Condylar Head Inclination With Respect to Glenoid Fossa in Cleft, Class III, and Class I Individuals. Journal of Indian Orthodontic Society 2021;55(2):146-149. doi: 10.1177/0301574220963414 Statement of Informed Consent: Since retrospective data was used, informed consent was obtained prior to the study during original data collection. Polke P, Jain U, Marothiya S, Agrawal P, Dixit S, Dubey C. Comparative Evaluation of Biofilm Adhesion to Different Types of Archwire and Microbiological Colonization During Orthodontic Treatment. Journal of Indian Orthodontic Society 2021;55(2):150-157. doi: 10.1177/0301574220957794 Statement of Informed Consent and Ethical Approval: informed consent was obtained during the study along with Institutional ethics approval numbered PCDS/ACAD/8/2015/48. Katti CG, Mohan A. Shopping for an Orthodontist. Journal of Indian Orthodontic Society 2021;55(2):158-168. doi: 10.1177/0301574220960304 Statement of Informed Consent: Informed consent is not required due to the study design being used-anonymous survey. Ramegowda S, Joy S, Gowda NC, Shailaja AM, Reddy B, Goel A. Assessment of Enamel Demineralization Adjacent to Orthodontic Brackets Using a Polarized Microscope. Journal of Indian Orthodontic Society 2021;55(1):49-55. doi: 10.1177/0301574220951694 Statement of Informed Consent and Ethical Approval: Informed consent was obtained during the study along with Institutional ethic approval prior to commencement dated 16 Nov 2016. Raghu Ram RSVM, Ranganayakulu I, Viswanadh KA, Kumar TSSM, Chaitanya TC, Sunil G. Level of Knowledge, Understanding, and Impact of the COVID-19 Pandemic on Continuing Fixed Orthodontic Treatment in Adults: A Questionnaire Study. Journal of Indian Orthodontic Society 2021;55(2):184-189. doi: 10.1177/0301574220988409 Statement of Informed Consent: Informed consent is not required due to the study design being used-anonymous survey. Dargahwala HS, Daigavane P, Vausdevan SD, Kamble R, Shrivastav S, Khakhar PG. Comparison of Cervical Vertebral Body Volume in Class II Vertical and Class II Horizontal Cases With Class I Cases Using 3D-DVT. Journal of Indian Orthodontic Society 2020;54(4):332-337. doi: 10.1177/0301574220947418 Statement of Informed Consent: Since retrospective data was used, informed consent was obtained prior to the study during original data collection. Agarwal SS, Londhe S, Mitra R, Datana D. Pre-treatment Factors Affecting Post-treatment Velopharyngeal Incompetency in Patients with Unilateral Cleft Lip and Palate Treated with Maxillary Rigid External Distraction. Journal of Indian Orthodontic Society 2020;54(3):226-232. doi: 10.1177/0301574220937459 Statement of Informed Consent: Since retrospective data was used, informed consent was obtained prior to the study during original data collection. Bajaj K, Rathee P, Goyal D. CBCT Evaluation of Condylar Changes in Class II Hyperdivergent Adult Patients Following Posterior Maxillary Intrusion Using Miniscrews/Miniplates—A Prospective Study. Journal of Indian Orthodontic Society 2020;54(2):121-126. doi: 10.1177/0301574219891627 Statement of Informed Consent and Ethical Approval: Informed consent was obtained prior to study in addition to ethical clearance which is already mentioned from the Rajasthan University of Health Sciences, Jaipur. Chakraborty S, Kidiyoor H, Patil AK. Effect of Light-Curable Fluoride Varnish and Conventional Topical Fluoride Varnish on Prevention of Enamel Demineralization Adjacent to Orthodontic Brackets: A Comparative Study. Journal of Indian Orthodontic Society 2020;54(1):14-23. doi: 10.1177/0301574219896025 Statement of Informed Consent and Ethical Approval: informed consent was obtained during the study along with Institutional ethics approval- 2016/P/ORTH/41.

Exposure to the oral environment enhances the corrosion of metal orthodontic appliances caused by fluoride-containing products: Cytotoxicity, metal ion release, and surface roughness

This study aimed to evaluate the metal ion release, cytotoxicity, and surface roughness of clinically used metal orthodontic appliances after immersion in different fluoride product solutions compared with those of new appliances. Used fixed appliances were debonded from 36 patients after their treatment was done. New appliances were as-received. Each used and new group comprised 36 sets of 20 brackets and 4 tubes that were divided into 3 groups by archwire type; stainless steel, nickel-titanium, and beta-titanium. The samples in each group were divided into 3 subgroups and immersed in solutions of fluoride toothpaste, 1.23% acidulated phosphate fluoride, or artificial saliva without fluoride as a control group. The immersion times were estimated from the recommended time for using each fluoride product for 3months. The samples were then immersed in Dulbecco's Modified Eagle's Medium for 7days. The cytotoxicity test was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay using primary gingival fibroblasts. Chromium, nickel, and iron ion release were detected using inductively coupled plasma mass spectroscopy. The surface roughness of the brackets and wires was measured by a scanning electron microscope and a noncontact optical 3-dimensional surface characterization and roughness measuring device. The data were analyzed using the paired t test and 2-way analysis of variance. Used brackets demonstrated a significantly higher ion release, surface roughness, and cytotoxicity than the new brackets. Acidulated phosphate fluoride significantly increased the ion release and surface roughness; however, it significantly decreased cell viability, especially in the titanium molybdenum subgroup. Used brackets were significantly prone to further corrosion. Acidulated phosphate fluoride gel should not be used in orthodontic patients with fixed metal appliances.

Effects of Diode and Nd:YAG Laser Irradiation on Friction Forces Between Two Types of Ceramic Brackets and Rhodium-Coated Archwires.

Introduction: Ceramic brackets have gained increasing popularity among dental clinicians and orthodontic patients but friction is a major concern when using them. This study sought to assess the effects of diode and Nd:YAG (neodymium-doped yttrium aluminum garnet) laser irradiation on friction forces between two types of ceramic brackets and rhodium-coated esthetic archwires. Methods: Thirty polycrystalline and 30 poly-sapphire brackets were divided into 6 groups (n=10) as follows: (I) control polycrystalline brackets (no laser irradiation), (II) polycrystalline brackets subjected to diode laser irradiation, (III) polycrystalline brackets subjected to Nd:YAG laser irradiation, (IV) control poly-sapphire brackets (no laser irradiation), (V) poly-sapphire brackets subjected to diode laser irradiation, and (VI) poly-sapphire brackets subjected to Nd:YAG laser irradiation. The bracket slots were laser-irradiated on a custom-made table. Sixty 5-cm pieces of rhodium-coated archwires were used for the friction test in a universal testing machine at a speed of 10 mm/min. Ten brackets from the six groups underwent scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDX). Results: The frictional resistance value of polycrystalline brackets was significantly higher than that of poly-sapphire brackets, irrespective of laser type (P <0.05). Irradiation of diode and Nd:YAG lasers, compared with the control group, had no significant effect on friction, irrespective of bracket type (P >0.05). Conclusion: It appears that diode and Nd:YAG laser irradiation cannot significantly decrease the friction. Future studies are warranted on different laser types with variable exposure.