The effect of salbutamol sulphate inhalation (an anti-asthmatic medication) on the surfaces of orthodontic Archwires.

OBJECTIVES: This study aimed to compare the surface roughness and friction of different orthodontic archwires after exposure to salbutamol sulphate inhalation, an anti-asthmatic medication. METHODS: Orthodontic archwires (stainless-steel [StSt], nickel-titanium [NiTi], beta-titanium [ß-Ti], and copper-NiTi [Cu-NiTi]) were equally divided into two groups. The exposed groups were subjected to 20 mg salbutamol sulphate for 21 days and kept in artificial saliva. The control groups were only kept in artificial saliva. Surface changes were visualized using scanning electron microscopy (SEM). The average surface roughness (Ra) was evaluated using atomic force microscopy (AFM), and friction resistance forces were assessed using a universal testing machine. Statistical analyses were performed using t-tests and ANOVA followed by post hoc tests. RESULTS: Salbutamol sulphate did not change the surface roughness of StSt and NiTi archwires (p > .05). However, the change in the surfaces of ß-Ti and Cu-NiTi archwires was significant (p < .001). The frictional forces of exposed StSt, NiTi, and Cu-NiTi archwires did not change (p > .05). However, the frictional forces of ß-Ti archwires increased significantly after exposure to salbutamol sulphate (p = .021). Brushing with fluoride after exposure to salbutamol sulphate increased the frictional forces of ß-Ti only (p = .002). CONCLUSIONS: Salbutamol sulphate inhalation significantly affected the surface texture of ß-Ti and Cu-NiTi orthodontic archwires and increased the friction of ß-Ti archwires. These deteriorating effects were not detected on the surface of StSt and NiTi archwires. Therefore, we suggest that ß-Ti and copper titanium archwires should be used cautiously in individuals under salbutamol sulphate inhalation treatment.

Comparison of transverse dimensional and incisor changes between wide and narrow orthodontic archwires: a randomized controlled trial.

OBJECTIVES: To clinically compare the effects of broader archwires to standard archwires, using conventional brackets in both cases, on the transverse and incisor changes in maxillary and mandibular arches during leveling and alignment. MATERIALS AND METHODS: Fifty-two patients presenting with crowding were allocated into two groups; one group received the broad Damon archwires while the other received standard 3M OrthoForm III Ovoid archwires. All participants were treated with conventional brackets using similar archwire sequences (0.014, 0.018, 0.016 × 0.022/0.016 × 0.025, 0.019 × 0.025 NiTi/CuNiTi archwires). Digital casts were obtained from alginate impressions before treatment (T0) and six weeks after inserting 0.019 × 0.025 NiTi archwires (T1). Pretreatment (T0) and post-alignment (T1) lateral cephalograms were obtained for each patient. The primary outcomes were the changes in the transverse arch dimensions and incisor inclination. The secondary outcomes were the horizontal and vertical linear changes in incisor position. RESULTS: Complete data were collected for 47 patients. There was a significant increase in arch width during treatment within each group, except for upper inter-molar width in 3M group (P = 0.071). Damon wire induced a statistically significant increase in maxillary inter-second premolar width (P = 0.042), and mandibular inter-first premolar (P = 0.043), inter-second premolar (P = 0.008) and inter-molar widths (P = 0.033) compared to 3M group. The increase in incisor proclination and the linear change in incisor position were significant within each group, with less mandibular incisor proclination (P = 0.004) and horizontal advancement (P = 0.038) in the Damon group. CONCLUSIONS: Damon archwires created a comparatively greater increase in the maxillary inter-second premolar width and the mandibular inter-first premolar, inter-second premolar, and inter-molar widths, and less proclination and horizontal advancement in mandibular incisors. The study provides invaluable evidence that using broad archwires with self-ligating brackets is the reason behind any greater expansion observed in this system rather than the unique mechanical and biological features exerted by the self-ligating system. CLINICAL RELEVANCE: Our results suggest that Damon archwire might be a better alternative compared to the narrower standard archwires that are usually used with conventional brackets, especially in the mandibular arch, in cases where mild to moderate crowding is planned to be resolved with a non-extraction approach. However, as arch expansion in the absence of posterior crossbites raises the question of long-term stability, the reported advantage of the use of wide wires should be interpreted with caution and should be considered in the retention phase, bearing in mind that achieving a good post-treatment occlusion is important for enhancing post-treatment stability.

A comparison between two orthodontic archwire sequences in terms of speed of alignment and root resorption: a randomized controlled clinical trial.

OBJECTIVES: To compare between two archwire (AW) sequences in terms of alignment speed and root resorption (RR). MATERIALS AND METHODS: Fifty-four patients (14 males, 40 females) requiring orthodontic treatment were randomly allocated into two groups; in group A (mean age 18.3) treatment started with 0.014″ nickel titanium (NiTi) followed by 0.019″×0.025″ NiTi AW while group B (mean age 18.9) the AW sequence was 0.014″ NiTi, 0.018″ NiTi, 0.016″×0.022″ NiTi, 0.019″×0.025″ NiTi. The primary outcome was to compare the alignment speed of the crowded upper and lower teeth between the two different AW sequences. The secondary outcome was to assess the magnitude of upper and lower incisors' root resorption (RR) measured by digital periapical radiographs taken at the start of treatment and 1 month after the placement of the working AW. t-test was used to compare the alignment speed and RR between the two groups. Statistical significance was predetermined at the P ≤ 0.05 level for all tests. RESULTS: The 54 patients were randomized in a 1:1 ratio to either group. Seven patients were excluded and complete data were obtained for 47 patients; 24 and 23 patients in group A and group B, respectively. There was no significant difference between the two groups in the alignment speed in the lower arch (P>0.05, mean difference=-0.44, 95% CI=-0.9 to 0.03) and root resorption (P>0.05). Alignment of upper arch was faster in group A (P < 0.0001, mean difference= - 0.9, 95% CI =-1.4 to -0.5). CONCLUSIONS: There is no significant difference between the two groups in the alignment speed in the lower arch and incisors' RR. Upper arch alignment was faster in group A. TRIAL REGISTRATION: Not registered.

Leveling the curve of Spee using different sized archwires: a randomized clinical trial of blood flow changes.

OBJECTIVES: To compare blood flow (BF) changes of teeth subjected to orthodontic forces during curve of Spee (COS) leveling using different archwires (AW). MATERIAL AND METHODS: Thirty subjects with COS > 5 mm were randomly assigned (1:1:1) into three groups based on the AW used: group 1: 0.017 × 0.025-inch stainless-steel (SS)AW, group 2: 0.019 × 0.025-inch SSAW, and group 3: 0.021 × 0.025-inch ß-titanium (TMA)AW. In the 3 groups, a 5 mm-depth reverse COS was placed in the AWs. A laser Doppler flowmeter was used to measure BF at different time intervals (T0-T4). RESULTS: In the 3 AWs group, BF of all measured teeth was reduced 20 min after force application. Afterwards, the BF values started to increase until the baseline values were almost restored within 1 week. Differences in BF changes between the extrusion and intrusion subgroups were observed within groups 1 and 3 during the first 20 min of force application (P < 0.05). Similar BF changes were recorded using the 3 different AWs. BF changes were associated with tooth type and the amount of COS depth change. CONCLUSIONS: During CoS leveling, similar BF changes were recorded using the 3 different AWs. Tooth type and the amount of COS depth change were associated with BF changes within the first 20 min of force application. Greater BF reduction was found in premolars compared to incisors during the first 20 min of AW placement. CLINICAL RELEVANCE: It is important to select a type of applied forces that minimally affect the BF. Intrusive forces appeared to have lower negative effects on the BF of teeth during COS leveling. TRIAL REGISTRATION: ClinicalTrial.gov (# NCT04549948).

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

BACKGROUND: The 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. METHODS: Three 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. RESULTS: The 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). CONCLUSIONS: Esthetic 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.

Efficacy of lower arch leveling, lower incisors' root resorption, and pain associated with the correction of curve of Spee using different orthodontic archwires: a randomized clinical trial.

OBJECTIVES: To compare between 3 archwires (AWs) for leveling curve of Spee (COS) in terms of efficacy of reduction, external apical root resorption (EARR), pain experienced, and the lower arch dimensional changes during COS leveling. TRIAL DESIGN: Randomized clinical trial. SETTING: Jordan University of Science and Technology Postgraduate dental clinics. MATERIAL AND METHODS: Fifty-three subjects with COS > 5 mm were included in this study. The subjects were randomly divided into three groups based on the AW used: group 1, 0.017 × 0.025-inch stainless-steel (SS) AW; group 2, 0.019 × 0.025-inch SS AW; and group 3, 0.021 × 0.025-inch ß-titanium (TMA) AW. The intervention was randomly allocated using the permuted random block size of 3 with a 1:1:1 allocation ratio. In the three groups, a 5-mm depth reverse COS was placed in the AWs. The following time points were defined for COS assessment: T1, before interventional leveling AW placement; and T2-T7, 1-6 months after interventional leveling AW placement. Records consisted of dental study models and periapical (PA) radiographs. Pain scores were recorded using visual analogue scale. Patients were followed up on a monthly basis until COS < 1.5 mm. MAIN OUTCOME MEASURES: COS depth reduction, lower incisors' EARR, pain scores, and arch dimensional changes. RESULTS: An overall reduction of 3.82 mm, 4.47 mm, and 3.85 mm of the depth of COS was achieved in groups 1, 2, and 3, respectively. The mean differences of 0.65 mm between groups 1 and 2 and 0.62 mm between groups 2 and 3 were significant at P < 0.05. Lower incisors' EARR during leveling COS ranged from 0.68 to 0.72 mm, from 0.63 to 0.82 mm, and from 0.53 to 0.88 mm in groups 1, 2, and 3, respectively (P > 0.05). Higher pain scores were reported by group 2 subjects during the first 24 h. Arch length and width increased significantly in groups 2 and 3 (P < 0.05). In all groups, COS leveling was achieved by lower incisor intrusion and proclination and lower molar extrusion. CONCLUSIONS: All investigated AWs were effective in leveling COS with minimal lower incisors' EARR (< 1 mm). COS was leveled by lower incisors' intrusion and proclination and lower molar extrusion. Pain scores were the highest in group 2 during the first 24 h. CLINICAL RELEVANCE: The 3 investigated leveling AWs were effective for the leveling COS and at the same time safe on the roots of the lower anterior teeth.

Assessment of Impact of Fluoride on Mechanical Properties of NiTi and CuNiTi Orthodontic Archwires: An In Vitro Study.

AIM: The current study was carried out to assess the impact on the mechanical properties of orthodontic wires such as the nickel-titanium (NiTi) and copper-nickel-titanium (CuNiTi) wires by fluoride available in various prophylactic products. MATERIALS AND METHODS: Fifty-six wire specimens were randomly divided into two groups-control group in which deionized water was used as a medium and study group in which Phos-Flur gel was used. Both study group and control group were divided into two subgroups-NiTi wire group: 0.019 × 0.025 inch NiTi archwires (14 specimens) and CuNiTi wire group: 0.019 × 0.025 inch CuNiTi archwires (14 specimens). Testing of all the wires was done under a universal force testing machine. RESULTS: Mean loading force among NiTi wire group and CuNiTi wire group specimens with deionized water as a medium was 682.6 and 397.4 MPa, respectively, while the mean loading force among NiTi wire group and CuNiTi wire group specimens with Phos-Flur gel as a medium was 596.1 and 368.4 MPa, respectively. While comparing between study group and control group among NiTi wires, significant results were obtained. Also, while comparing between study group and control group among CuNiTi wires, significant results were obtained. CONCLUSION: Following exposure to fluoride agents, NiTi wires and CuNiTi wires are significantly associated with reduced mechanical properties. CLINICAL SIGNIFICANCE: Although fluoride acts as a vital adjunct in maintaining oral hygiene, particularly among patients undergoing fixed orthodontic treatment, its influence on the mechanical properties of the wires is an area to be explored further; thereby, its use is to be monitored.

[Assessment of dental arches expansion using ligature and passive self-ligating braces in combination with Pitts broad arches and early elastics]. / Otsenka rasshireniya zuboal'veolyarnykh dug u patsientov pri ispol'zovanii ligaturnykh i passivnykh samoligiruyushchikh breket-sistem v sochetanii s dugami Pittsa shirokoi formy i rannei elastichnoi tyagi.

THE AIM OF THE STUDY: Was to analyze the effectiveness of the use of Pitts Broad and early elastics in the treatment of patients with narrowing and deformation in dentition. MATERIALS AND METHODS: The results of orthodontic treatment of 46 adult patients with narrowing and deformation in dentition are presented. Patients were separated in 2 groups, depending on the algorithm of treatment: group 1 - using the braces of passive self-ligation, Pitts Broad and early short elastics; group 2 - using ligature braces and archwires Orthos. RESULTS: Biometric analysis of the diagnostic models of the 1st group after treatment showed a significant increase in the area of the premolars on the upper (between premolars - 39.8±0.4 mm, between molars - 48.3±0.5 mm) and lower (between premolars - 37.1±0.5 mm, between molars - 46.3±0.6 mm) jaws compared to the data before treatment. Biometric analysis of the diagnostic models of the 2d group showed that expansion in the area of the molars was achieved in a much smaller volume in the upper and lower jaws, compared with the 1st group (upper jaw: between premolars - 35.7±0.4 mm, between molars - 43.5±0.5 mm; lower jaw: between premolars - 33.2±0.3 mm, between molars - 42.3±0.5 mm). CONCLUSION: The passive self-ligation system in combination with protocol of Pitts Broad already contributes the expansion of dentition in aesthetically significant areas (distal regions) in the early stages of treatment. Using of early light elastics provides an early control of the lateral tooth torque, which allows achieving a harmonious and wide smile at the end of treatment.

Comparison of the microbial flora from different orthodontic archwires using a cultivation method and PCR: A prospective study.

OBJECTIVE: The aim of this study was to evaluate the effects of superelastic nickel-titanium (SE NiTi), copper-nickel-titanium (CuNiTi) and titanium-molybdenum alloy (TMA) archwires with different surface properties on dental plaque retention and microbial colonization. SETTING AND SAMPLE POPULATION: Totally 25 individuals, consisting of 16 girls and nine boys with mean age of 15.69 ± 1.70, were included in this study. MATERIAL AND METHODS: The effects of the SE NiTi, CuNiTi and TMA archwires with different surface properties on the amount of Streptoccocus sp and Lactobacillus sp were investigated with three different parameters including clinical periodontal indexes, microbial swab and archwire samples. Phenotypic isolation was performed from microbial swab and archwire samples using culture method; genotypic isolations were performed by the polymerase chain reaction method. RESULTS: There was no statistically significant difference between SE NiTi, CuNiTi and TMA archwires in terms of periodontal parameters (P > .05). When microbial swabs and archwires samples from different archwire groups were evaluated by culture method, no statistically significant difference was found between the groups (P > .05). A statistically significant difference was found between the amount of Lactobacillus sp in the swab samples of the CuNiTi archwire after the purification period (P = .023). S mutans were found to be more quantity than other bacterial types in all archwires. CONCLUSION: The amount of microbial involvement was found to be lower in CuNiTi archwires than in the post-purification period. This may be due to the antimicrobial effect of copper.

Review of Superelastic Differential Force Archwires for Producing Ideal Orthodontic Forces: an Advanced Technology Potentially Applicable to Orthognathic Surgery and Orthopedics.

PURPOSE OF REVIEW: Gentle and continuous loads are preferred for optimum orthodontic tooth movement. Nitinol, an alloy of nickel and titanium developed for the aerospace industry, found its first clinical applications in orthodontics because it has ideal load-deflection behavior. The purpose of this review is to elucidate the criteria for effective orthodontic mechanics relative to emerging Nitinol technology. The specialized materials with variable stiffness that were originally developed for orthodontics are increasingly attractive for in the temporomandibular joint, orthognathic surgery, and orthopedics. RECENT FINDINGS: The evolution of orthodontic archwires is driven by a need to achieve low load-deflection characteristics and Nitinol is the alloy of choice. Scientific knowledge of the biological response to orthodontic forces continues to grow, but definitive guidance on optimal force levels for individual teeth is elusive. Finite element models (FEM) that take into account periodontal ligament (PDL) stresses indicate differential force archwires are needed to realize optimal treatment. However, previous wire fabrication methods, including welding of different materials and selective resistive heating, are limited by poor mechanical performance and spatial resolution. Recently, a novel laser processing technique was developed for precisely programing relative levels of stiffness in a single archwire. FEM was used to estimate the optimal force for each tooth by calculating the 3D bone-PDL surface area. There remains a general consensus that light and continuous forces are desirable for orthodontic treatment. New developments in archwire materials and technology have provided the orthodontist with a complete spectrum of load-deflection rates and differential force options to express these forces with maximized archwire economy. These technologies also appear to have application to orthopedic implant devices.

An in vitro Evaluation of Friction Characteristics of Conventional Stainless Steel and Self-ligating Stainless Steel Brackets with different Dimensions of Archwires in Various Bracket-archwire Combination.

AIM: The purpose of this research is to compare the frictional attributes of stainless steel conventional brackets and self-ligating stainless steel brackets with different dimensions of archwires. MATERIALS AND METHODS: The test was carried with two sets of maxillary brackets: (1) Conventional stainless steel (Victory Series), (2) stainless steel self-ligating (SmartClip) without first premolar brackets. Stainless steel, nickel-titanium (NiTi), and beta-Ti which are the types of orthodontic wire alloys were tested in this study. To monitor the frictional force, a universal testing machine (Instron 33R 4467) that comprises 10 kg tension load cell was assigned on a range of 1 kg and determined from 0 to 2 kg, which allows moving of an archwire along the brackets. One-way analysis of variance was used to test the difference between groups. To analyze the statistical difference between the two groups, Student's t-test was used. RESULTS: For Victory Series in static friction, p-value was 0.946 and for kinetic friction it was 0.944; at the same time for SmartClip, the p value for static and kinetic frictional resistance was 0.497 and 0.518 respectively. Hence, there was no statistically significant difference between the NiTi and stainless steel archwires. CONCLUSION: It is concluded that when compared with conventional brackets with stainless steel ligatures, self-ligating brackets can produce significantly less friction during sliding. Beta-Ti archwires expressed high amount of frictional resistance and the stainless steel archwires comprise low frictional resistance among all the archwire materials. CLINICAL SIGNIFICANCE: In orthodontics, frictional resistance has always had a major role. Its ability to impair tooth movement leads to the need for higher forces to move the teeth and it extends the treatment time which results in loss of posterior anchorage. Friction in orthodontics is related with sliding mechanics when a wire is moving through one or a series of bracket slots.

An in vitro study into the efficacy of complex tooth alignment with conventional and self-ligating brackets.

OBJECTIVE: To evaluate the efficacy of tooth alignment achieved by various small cross-section archwire/bracket combinations using the orthodontic measurement and simulation system. MATERIALS AND METHODS: The study comprised three types of orthodontic brackets 1) conventional ligating (Victory Series and Mini-Taurus), 2) self-ligating (SmartClip a passive self-ligating bracket and Time3 an active self-ligating bracket), and 3) a conventional low-friction bracket (Synergy). All brackets had a nominal 0.022″ slot size. Brackets were combined with 1) 0.012″ stainless steel, 2) 0.012″ Orthonol, 3) 0.012″ Thermalloy, and 4) 0.0155″ coaxial archwires. Archwires were tied to the conventional brackets with stainless steel ligatures and elastomeric rings. The malocclusion simulated represented a central upper incisor displaced 2 mm gingivally (x-axis) and 2 mm labially (z-axis). RESULTS: The inciso-gingival correction achieved by the different archwire/bracket combinations ranged from 15 to 95%, while the labio-lingual correction ranged from 10 to 95%. The smallest correction was achieved by coaxial, Orthonol, and thermally archwires when ligated with the elastomeric rings to conventional brackets. Stainless steel archwires achieved from 65 to 90% of inciso-gingival correction and from 60 to 90% of labio-lingual correction. CONCLUSION: The resultant tooth alignment was the product of interaction between the archwire type, bracket type, and bracket design including ligature type. Small cross-sectional archwires might produce up to 95% correction if combined properly with the bracket system. Elastomeric rings when used with conventional brackets limit the efficacy of malalignment correction.

Deflection Evaluation of Thermoactivated Nickel-Titanium Archwires after Heat Treatment on their Distal Ends.

OBJECTIVE: This study evaluated in vitro the mechanical changes of 0.018" (0.45 mm) and 0.016 × 0.022" (0.40 × 0.55 mm) thermoactivated nickel-titanium archwires subjected to heat treatment on their distal ends. MATERIALS AND METHODS: Ten archwires in diameters 0.018" and 0.016 × 0.022" by different manufacturers Ormco, Morelli, Orthometric and Unitek were tested. Each tested archwire had an experimental side, submitted to heat treatment, and an annealing-free control. Tests for load/deflection were performed using a universal testing machine, with temperature control in the austenitic transformation phase through tempe rature-controlled chamber. The variables showed normal distribution (Kolmogorov-Smirnov), the t-student test was applied in order to observe the difference between the experi mental and control groups. Statistical significance was set at p < 0.05. RESULTS: There were no statistically significant differences between the groups. CONCLUSION: Heat treatment carried out in the region corresponding to the first molar distal region on thermoactivated nickel-titanium archwires did not influence the load/deflection values in adjacent portion.

Effectiveness of laser-engineered copper-nickel titanium versus superelastic nickel-titanium aligning archwires: A randomized clinical trial.

Objective: : To compare the effectiveness of laser-engineered copper-nickel titanium (SmartArch) and superelastic nickel-titanium (SENT) archwires in aligning teeth and inducing root resorption and pain experienced by patients. Methods: : Two-arm parallel groups with a 1:1 allocation ratio were used. The participants were patients aged 11.5 years and older with 5-9 mm of mandibular anterior crowding who were indicated for non-extraction treatment. The primary outcome was alignment effectiveness, assessed using Little's irregularity index (LII) over 16 weeks with a single wire (0.016-inch) in the SmartArch group and 2 wires (0.014- and 0.018-inch) in the SENT group (8 weeks each). Secondary outcomes included root resorption evaluated by pre- and post-intervention periapical radiographs and pain levels recorded by the participants during the first week. Results: : A total of 40 participants were randomly allocated into 2 groups; 33 completed the study and were analyzed (16 in the SmartArch group and 17 in the SENT group, aged 16.97 ± 4.05 years). The total LII decrease for the SmartArch and SENT groups was 5.63 mm and 5.29 mm, respectively, which was neither statistically nor clinically significant. Root resorption was not significantly different between the groups. The difference in pain levels was not statistically significant for the first 5 days following wire placement; however, there was a significant difference favoring the SENT group in the final 2 days. Conclusions: : SmartArch and SENT archwires were similarly effective during the alignment phase of orthodontic treatment. Root resorption should be observed throughout the treatment with either wire. SmartArch wires demonstrated higher pain perception than SENT wires.

Multi-Force Bio-Active™ Archwires and Various Contemporary NiTi Multi-Force Archwires: Properties and Characteristics-A Review.

The manufacturing of orthodontic archwires made from NiTi alloy has undergone numerous changes from the second half of the last century to modern times. Initially, superelastic-active austenitic NiTi alloys were predominant, followed by thermodynamic-active martensitic NiTi alloys, and, finally, the most recent development was graded thermodynamic alloys. These advancements have been the subject of extensive investigation in numerous studies, as they necessitated a deeper understanding of their properties. Furthermore, it is imperative that we validate the information provided by manufacturers regarding these archwires through independent studies. This review evaluates existing studies on the subject with a specific focus on the Bio-active multi-force NiTi archwire, by examining its mechanical, thermal, and physicochemical properties before and after clinical use. This archwire consists primarily of Ni and Ti, with traces of Fe and Cr, which release graduated, biologically tolerable forces which increase in a front-to-back direction and are affected by the temperature of the environment they are in. The review provides information to practicing orthodontists, facilitating informed decisions regarding the selection and use of Bio-active™ archwires for individual patient treatments.

DNA fragmentation of lymphocytes and sperm cells induced by nickel released from orthodontic archwires: A preliminary study.

Orthodontic brackets and archwires placed intraorally are subject to corrosion, leading to the release of cytotoxic metal ions. The aim of this study was to determine whether the use of orthodontic NiTi archwires increases systemic Ni levels and cause alterations on the DNA of cells unrelated to the oral environment such as lymphocytes and sperm cells. Human urine, semen and blood samples were collected before (baseline) sham placement of orthodontic archwires and 15 and 30 days after placement. Lymphocytes and sperm cells cells were evaluated by comet assay. Ni concentration levels in urine increased significantly between baseline and 15 days (p<0.01) and 15 and 30 days of exposure (p<0.01). Progressive decrease in sperm viability and motility was observed between the sampling periods. Lymphocytes and sperm cells showed DNA fragmentation. The increase in systemic concentration of nickel induced structural damage in the DNA of lymphocytes and human sperm cells.

A Comparative Evaluation of Surface Hardness and Nanomechanical Properties of Nickel-Titanium Orthodontic Wires: An In Vitro Study.

OBJECTIVE: The study aimed to evaluate the influence of various surface coatings (epoxy, Teflon, and rhodium) on the surface roughness (SR) and nanomechanical characteristics of nickel-titanium (NiTi) archwires. The study compared these coated archwires to uncoated ones from a single manufacturer, which served as a control. MATERIALS AND METHODS: There were 15 rectangular samples of four distinct archwires measuring 0.17 × 0.25. These were ultrasonically treated with an alkaline solution at 60°C for 15 minutes before being rinsed with distilled water to remove precipitates. With an orthodontic soft wire cutter, the straight buccal sections of coated and uncoated archwires were cut into 20 mm lengths. A three-dimensional optical noncontact surface profilometer evaluated the surface. Profilometers use contact scanning white light interferometry. Using the Vision64 software (Bruker Corporation, San Jose, CA), the profilometer's nanolens atomic force microscopy module has a completely automated turret with programmed X, Y, and Z motions. Images were taken in five random locations. Five average measurements matched specimen SR. A nanoindenter with a Berkovich diamond indenter measured nanohardness (NH) and elastic modulus (EM). The experimental results were analyzed using the Statistical Package for the Social Sciences software version 26.0 (SPSS Inc., Chicago, IL). To examine mean differences at 5% significance, analysis of variance and Tukey's post hoc test were applied for SR, NH, and EM. RESULTS: Wires coated with epoxy had the highest SR (1.499 ± 0.082), followed by Teflon (0.811 ± 0.023) and rhodium (0.308 ± 0.024). The SR of the control group was 0.289 ± 0.027. Significant differences in SR were found (p < 0.0001). Except for the comparison between rhodium and the control group (p = 0.684), all intergroup comparisons of SR showed significant differences (p < 0.0001). The rhodium-coated wires exhibited the highest NH (0.185 ± 0.014), and the epoxy group had the lowest (0.147 ± 0.017). Variations in NH were significant between the study groups (p < 0.0001). The epoxy, Teflon, and rhodium groups showed significant differences against the control group (p < 0.0001) in intergroup comparisons for NH. The Teflon group had the highest EM (5.367 ± 0.379), and the epoxy group had the lowest (5.012 ± 0.498). The EM of the control group was 56.946 ± 0.737. Results indicate considerable EM changes between the groups (p < 0.05). Comparisons between experimental and control groups showed significant differences (p < 0.0001). CONCLUSION: The study's findings indicate that the SR of rhodium-coated archwires is substantially comparable to that of uncoated archwires. However, Teflon-, rhodium-, and epoxy-coated archwires had significantly different NH and EM compared to uncoated ones. Further, uncoated archwires have higher NH and EM.

Robotic Archwire Bending in Orthodontics: A Review of the Literature.

Malocclusion is a widespread oral health issue that adversely affects individuals' health and well-being. Currently, fixed orthodontics is considered the most efficient treatment for correcting malocclusion, with archwire bending playing a key role in orthodontic treatment. Traditionally, orthodontists manually performed archwire bending using various handheld pliers and other mechanical tools, requiring a significant amount of time, precision, and specialized training yet being unable to guarantee appliance accuracy. The process of shaping orthodontic wire is challenging due to its high stiffness and superelasticity, resulting in a time-consuming, laborious process that is prone to human errors. With advancements in orthodontics, traditional methods have taken a backseat, making way for innovative technologies that provide more accurate and personalized treatment options. The continuous efforts to enhance treatment efficiency, accuracy, efficacy, and patient experience have led to the integration of robotics into various orthodontic procedures. The use of robotics in archwire bending represents a breakthrough in orthodontics, offering unparalleled precision, consistency, and efficiency. This technology reduces treatment time and patient discomfort, overcoming the limitations of manual bending and enhancing orthodontic treatment overall. Hence, the present study aims to review the literature on robotic archwire bending in orthodontics, including their drawbacks and their impact on orthodontic treatment.

Comparison of Surface Roughness of Different Orthodontic Archwires: Atomic Force Microscopic Study.

BACKGROUND: Surface roughness (SR) of dental components is significant because it impacts the surface area of the contact surface, which in turn affects corrosion behavior and biological compatibility. Orthodontic archwires (OA) with SR can affect the coefficient of friction, which in turn affects how effectively sliding biomechanics work and how the orthodontic appliance works efficiently. AIM: The objectives of the present investigation were to examine the SR of five distinct kinds of OA using an atomic force microscope (AFM) and to assess the merits of using AFM to analyze orthodontic materials. METHODS: For this investigation, there were five distinct orthodontic archwires with rectangular cross-sectional geometry. There were assigned different categories: Category 1: SmartArch wires (Ormco) (n=20), Category 2: Damon wires (Ormco) (n=20), Category 3: heat-activated nickel-titanium (HANT) wires (G&H Orthodontics) (n=20), Category 4: nickel-titanium (NiTi) wires (G&H Orthodontics) (n=20), Category 5: stainless steel (SS) wires (Ormco) (n=20). Each wire category's 20 samples were selected. Ten samples from each category had 5 mm of wire clipped from the finish point of the archwires. These were observed using the AFM in natural lighting. Using a cyanoacrylate glue that dries quickly, the samples were fastened to a metal holder. Ten randomly chosen patches of the surface, each measuring 15 × 15 µm, were taken from every sample and examined (N = 500). RESULTS: The mean values of roughness average (Ra) in category 1, category 2, category 3, category 4 and category 5 were 23.08 ± 17.66, 26.78 ± 5.65, 26.66 ± 3.89, 9.71 ± 0.29 and 11.29 ± 2.12 respectively. The values of Ra representing SR were greatest in category 3 (HANT wires) followed by category 2 (Damon wires) while values of SR were minimum in category 4 (NiTi wires) and category 5 (stainless steel wires). The findings had statistical significance also. CONCLUSION: The SR of stainless steel wire was discovered to be less than that of the other wires. The SR may have an impact on the efficiency of sliding mechanics as well as the appeal and corrosion resistance of orthodontic components.

Novel approach for characterizing clinical load application of superelastic orthodontic wires.

OBJECTIVE: Current standardized in vitro bending experiments for orthodontic archwires cannot capture friction conditions and load sequencing during multi-bracket treatment. This means that clinically relevant forces exerted by superelastic wires cannot be predicted. To address these limitations, this study explored a novel test protocol that estimates clinical load range. METHODS: The correction of a labially displaced maxillary incisor was simulated using an in vitro model with three lingual brackets. Deflection force levels derived from four different protocols were designed to explore the impact of friction and wire load history. These force levels were compared in nickel-titanium (NiTi) archwires with three commonly used diameters. The unloading path varied between protocols, with single or multiple sequences and different load orders and initial conditions. RESULTS: Deflection forces from the new protocol, employing multiple continuous load/unload cycles (CCincr), consistently exceeded those from the conventional protocol using a single continuous unloading path (CUdecr). Mean differences in plateau force ranged from 0.54 N (Ø 0.014" wire) to 1.19 N (Ø 0.016" wire). The CCinr protocol also provided average force range estimates of 0.47 N (Ø 0.012" wire), 0.89 N (Ø 0.014" wire), and 1.15 N (Ø 0.016" wire). SIGNIFICANCE: Clinical orientation towards CUdecr carries a high risk of excessive therapeutic forces because clinical loading situations caused by friction and load history are underestimated. Physiological tooth mobility using NiTi wires contributes decisively to the therapeutic load situation. Therefore, only short unloading sequences starting from the maximum deflection in the load history, as in CCincr, are clinically meaningful.