nitinol and Malocclusion

To compare tooth movement achieved, time required for alignment, root resorption, and alveolar bone thickness changes during initial dental alignment between groups treated with 0.012-inch preformed heat-activated or customized nickel titanium (NiTi) archwires.. Thirty-two subjects (mean age 19.8 ± 1.7 years) with severe crowding of maxillary anterior teeth had premolar extractions and were randomly allocated into control and experimental groups receiving preformed heat-activated and customized NiTi archwires, respectively. Limited field of view cone-beam computed tomographies were taken initially (T. Central incisor tooth movement was significantly different (all P ≤ .003) between groups at all time points. T. The experimental group exhibited palatal movement of the central incisors, more canine distal movement with less bone thickness changes, and less root resorption but took more time to achieve alignment than the control group.

Topics: Adolescent; Adult; Alloys; Alveolar Bone Loss; Cone-Beam Computed Tomography; Female; Humans; Male; Malocclusion; Orthodontic Wires; Root Resorption; Tooth Movement Techniques; Treatment Outcome; Young Adult

The aim of this clinical trial was to investigate the duration of mandibular-crowding alleviation with piezotome-corticision orthodontics compared with conventional orthodontics.. Single-centre, two-arm parallel group randomized controlled trial.. Orthodontic clinic at the University of Connecticut.. The study was approved by the Institutional Review Board (IRB # 12-0147-2).. Forty-one adult subjects from a single centre with more than 5mm of mandibular anterior crowding were randomly allocated using block randomization into experimental and control groups. The experimental group received a corticision procedure with a piezotome on the labial aspect of the mandibular incisors in conjunction to a self-ligation fixed orthodontic appliance. The control group received the self-ligation fixed orthodontic appliance and no corticision. Same archwire sequence (0.014 inch followed by 0.014 × 0.025 inch copper-nickel-titanium) was followed for both groups. Mandibular study casts taken every 4-5 weeks were used to assess changes in the irregularity index by blinded outcome assessors.. The time to alignment was calculated in days.. Twenty-nine subjects (16 experimental and 13 control) completed the study. Overall, no significant difference in the time required to correct mandibular crowding with piezotome-corticision assisted (102.1 ± 34.7 days; 95% CI, 83.6 to 120.6) and conventional orthodontics (112 ± 46.2 days; 95% CI, 84-139.9) was observed. No complications with treatment or unintended consequences were observed on any of the subjects.. A high attrition rate.. This randomized clinical trial found no evidence that piezotome-corticision assisted orthodontics was more efficient in alleviating mandibular anterior crowding.. ClinicalTrials.gov, Identifier: NCT02026258.. Division of Orthodontics, University of Connecticut.. None.

Topics: Adolescent; Adult; Alloys; Female; Humans; Incisor; Male; Malocclusion; Mandible; Nickel; Orthodontic Appliance Design; Orthodontic Brackets; Orthodontic Wires; Piezosurgery; Single-Blind Method; Titanium; Tooth Movement Techniques

To clinically evaluate the pain intensity during the week following initial placement of three different orthodontic aligning archwires.. A consecutive sample of 75 patients requiring upper and lower fixed orthodontic appliances were alternately allocated into three different archwires (0.014-inch superelastic NiTi, 0.014-inch thermoelastic NiTi or 0.014-inch conventional NiTi). Assessments of pain/discomfort were made on a daily basis over the first 7-day period after bonding by means of visual analog scale and consumption of analgesics. The maximum pain score was recorded. The possible associations between age, gender, degree of crowding, and teeth irregularity and the pain intensity were also examined. Demographic and clinical differences between the three groups were compared with chi-square test or analysis of variance (ANOVA) test.. No statistically significant differences were found in the pain intensity when the three aligning NiTi archwires were compared (P  =  .63). No significant differences in pain perception were found in terms of gender, age, lower arch crowding, and incisor irregularity. The intake of analgesics was the least in the superelastic NiTi group.. The three forms of NiTi wires were similar in terms of pain intensity during the initial aligning stage of orthodontic fixed appliance therapy. Gender, age, and the degree of crowding have no effect on the perceived discomfort experienced by patients undergoing fixed orthodontic treatment.

Topics: Alloys; Dental Alloys; Double-Blind Method; Female; Humans; Male; Malocclusion; Orthodontic Wires; Pain; Pain Measurement; Prospective Studies; Young Adult

To compare the efficiency of orthodontic archwire sequences produced by three manufacturers.. Prospective, randomized clinical trial with three parallel groups.. Private orthodontic practice in Caloundra, QLD, Australia.. One hundred and thirty-two consecutive patients were randomized to one of three archwire sequence groups: (i) 3M Unitek, 0·014 inch Nitinol, 0·017 inch × 0·017 inch heat activated Ni-Ti; (ii) GAC international, 0·014 inch Sentalloy, 0·016 × 0·022 inch Bioforce; and (iii) Ormco corporation, 0·014 inch Damon Copper Ni-Ti, 0·014 × 0·025 inch Damon Copper Ni-Ti. All patients received 0·018 × 0·025 inch slot Victory Series™ brackets.. Mandibular impressions were taken before the insertion of each archwire. Patients completed discomfort surveys according to a seven-point Likert Scale at 4 h, 24 h, 3 days and 7 days after the insertion of each archwire. Efficiency was measured by time required to reach the working archwire, mandibular anterior alignment and level of discomfort.. No significant differences were found in the reduction of irregularity between the archwire sequences at any time-point (T1: P = 0·12; T2: P = 0·06; T3: P = 0·21) or in the time to reach the working archwire (P = 0·28). No significant differences were found in the overall discomfort scores between the archwire sequences (4 h: P = 0·30; 24 h: P = 0·18; 3 days: P = 0·53; 7 days: P = 0·47). When the time-points were analysed individually, the 3M Unitek archwire sequence induced significantly less discomfort than GAC and Ormco archwires 24 h after the insertion of the third archwire (P = 0·02). This could possibly be attributed to the progression in archwire material and archform.. The archwire sequences were similar in alignment efficiency and overall discomfort. Progression in archwire dimension and archform may contribute to discomfort levels. This study provides clinical justification for three common archwire sequences in 0·018 × 0·025 inch slot brackets.

Topics: Adolescent; Alloys; Dental Alloys; Dental Arch; Female; Follow-Up Studies; Humans; Male; Malocclusion; Mandible; Nickel; Orthodontic Appliance Design; Orthodontic Wires; Pain Measurement; Prospective Studies; Single-Blind Method; Stainless Steel; Time Factors; Titanium; Tooth Movement Techniques; Treatment Outcome

A recently developed orthodontic wire alloy known as GUMMETAL® is claimed to deliver more physiological forces to correct dental mispositioning. However, its mechanical characteristics have not been fully characterized yet. This study aimed to determine and compare the elastic properties of different wire alloys, such as nickel-titanium (NiTi), stainless steel (SS), and GUMMETAL®, and assess their unloading forces when combined with either conventional or self-ligating brackets (CL and SL) when correcting dental crowding. All wires had a 0.016″ cross-section diameter. A three-point bending test was performed to assess the maximum deflection of each wire. Then, a subsequent analysis measured the unloading force for each wire/bracket system in a dental crowding clinical simulation device. The test was carried out in a universal testing machine with a cross-speed displacement of 0.5 mm/min. Data were recorded in different ranges and statistically evaluated using two-way analysis of variance. GUMMETAL® displayed higher unloading mean forces in SL brackets (2228.78 cN) than CL brackets (1967.38 cN) for the 1.6-3.0 deflection interval (p = 0.018). Within this interval, NiTi showed higher forces when used with CL brackets (2683.06 cN) than with SL brackets (1179.66 cN) (p < 0.0001). For the CL bracket systems, SS wires showed higher forces (2125.31 cN) in the 1.0-1.6 deflection interval than the other two wire alloys (NiTi, 1541.52 cN and GUMMETAL®, 852.65 cN) (p < 0.0001). SS wires also displayed lower forces with SL brackets (1844.01 cN) than in CL brackets (2125.31 cN) (p = 0.049). Thus, only GUMMETAL® revealed to be an optimal choice for SL brackets, whereas NiTi for CL brackets.

Topics: Alloys; Computer Simulation; Dental Alloys; Elasticity; Friction; Humans; In Vitro Techniques; Malocclusion; Materials Testing; Mechanical Phenomena; Nickel; Orthodontic Brackets; Orthodontic Wires; Stainless Steel; Stress, Mechanical; Titanium

Our objectives are to analyse and to compare the stress distribution and displacement of the craniofacial structures, following the application of forces from quad-helix and Nickel Titanium Palatal Expander-2 (NPE2) using finite element analysis.. Three-dimensional finite element models of young dried human skull, quad-helix appliance and NPE2 were constructed, and the initial activation of the expanders was stimulated to carry out the analysis and to evaluate the Von Misses stresses and displacement.. Both the models demonstrated the highest stresses at the mid-palatal suture, with maximum posterior dislocation. The second highest stress was recorded at the fronto-zygomatic suture. The pattern of stress distribution was almost similar in both the groups, but NPE2 revealed lower magnitude stresses than quad-helix. The only exception being quad-helix model showed high stress levels around pterygo-maxillary suture whereas minimal stress around pterygo-maxillary suture was noticed after NPE2 activation. The cusp of the erupting canine and the erupting mesiobuccal cusp of the second molar showed outward, backward and downward displacement signifying increase in their eruption pattern following maxillary expansion.. Maxillary expansion using quad-helix and NPE2 can be used in posterior crossbite correction in cases where maximum skeletal changes are desirable at a younger age; it is furthermore effective in treating young patients with impacted or displaced teeth. Quad-helix and NPE2 produced acceptable forces for orthopaedic treatment even after being orthodontic appliances; their clinical application should be correctly planned as the effects of these appliances are largely age dependent.

Topics: Alloys; Child; Computer Simulation; Computer-Aided Design; Cranial Sutures; Cuspid; Dental Arch; Dental Stress Analysis; Finite Element Analysis; Humans; Malocclusion; Maxilla; Models, Anatomic; Models, Biological; Molar; Nasal Bone; Nose; Orthodontic Anchorage Procedures; Orthodontic Appliance Design; Orthodontic Appliances; Palatal Expansion Technique; Palate; Palate, Hard; Skull; Tomography, X-Ray Computed; Zygoma

Micro-implant is a device that is temporarily fixed to bone for the purpose of enhancing orthodontic anchorage either by supporting the teeth of the reactive unit or by obviating the need for the reactive unit altogether, and which is subsequently removed after use. The purpose of this study was to evaluate the clinical efficiency of micro-implants in reinforcing anchorage during the initial retraction of anterior teeth, check the rate of initial retraction for 8 weeks, and assess the stability of micro-implants during this period. Eighteen micro-implants were placed (10 in the maxilla and 8 in the mandible) and immediately loaded with 200-250 g of force using 9-mm closed coil Nitinol springs. The amount of space closure was measured every 2 weeks until the eighth week. Cephalometric measurements were made at the end of the study to evaluate anchor loss, if any. Micro-implant stability was also assessed. The rate of initial retraction in the maxilla at the end of 8 weeks was 1.65 mm/quadrant and 1.51 mm/quadrant in the mandible. The amount of retraction on the left side of the arches was 1.66 mm/quadrant and 1.49 mm/quadrant on the right side. The average initial retraction for both arches per month was 0.78 mm. An anchor loss of 0.1 mm (0.06%) was observed in the maxilla while no mandibular anchor loss was recorded. The rate of initial retraction observed in the maxilla was more than that achieved in the mandible. Initial retraction was also more on the left side of the arches. There was no anchor loss in the mandible. The micro-implant-reinforced anchorage was helpful in minimizing anchor loss and accepted heavy traction forces but did not bring about a faster rate of retraction.

Topics: Adolescent; Alloys; Cephalometry; Dental Alloys; Dental Arch; Dental Implants; Follow-Up Studies; Humans; Malocclusion; Mandible; Maxilla; Miniaturization; Orthodontic Anchorage Procedures; Orthodontic Appliance Design; Orthodontic Space Closure; Orthodontic Wires; Osseointegration; Radiography, Bitewing; Stress, Mechanical; Time Factors; Treatment Outcome; Young Adult

Topics: Adolescent; Alloys; Child; Dental Alloys; Female; Humans; Male; Malocclusion; Malocclusion, Angle Class II; Orthodontic Appliance Design; Orthodontic Brackets; Orthodontic Wires; Tooth Eruption, Ectopic; Tooth Movement Techniques; Young Adult

The purpose of the study was to evaluate interleukin-6 production, in saliva-activated mononuclear cell cultures from malocclusion patients, before and after placement of .014 NiTi archwires.Four patients receiving .014 Nitinol archwire to correct malocclusion participated in this study. Samples of their blood and saliva were collected before and after placement of the apparatus. Mononuclear cells were obtained from the blood using the Ficoll-Paque (1.077 g/ml) density gradient separation method. Mononuclear Cells were activated with saliva from each patient and were cultured in 96-well plates for 72 hours. Samples were collected at 24 hours before apparatus placement, and at 24 hours and 72 hours after placement. IL-6 expression levels in the cell culture supernatants were quantified by ELISA. An increase in IL-6 levels in the cell culture supernatants was observed 24 hours after placement of the orthodontic apparatus relative to the negative control (p = 0.002) and IL-6 came to basal limits 72 hours after apparatus placement.IL-6 quantification may be useful as a biomarker to estimate the inflammatory response caused by forces applied during orthodontic treatment and their levels came to basal limits 72 hours after apparatus placement in patients without systemic diseases. The isolation of saliva components involved in such effects is important to study the mechanisms to control the acute inflammation in oral cavity after apparatus placement.

Topics: Adolescent; Adult; Alloys; Biomarkers; Cells, Cultured; Enzyme-Linked Immunosorbent Assay; Female; Humans; Inflammation Mediators; Interleukin-6; Leukocytes, Mononuclear; Male; Malocclusion; Mexico; Orthodontic Appliance Design; Orthodontic Wires; Pilot Projects; Saliva; Time Factors; Young Adult

The finite element method has been used to determine the stress distribution generated by the initial placement of a simulated preset bracket-type orthodontic appliance utilizing titanium-nickel alloy archwire.

Topics: Alloys; Dental Alloys; Elasticity; Humans; Malocclusion; Models, Biological; Orthodontic Appliances; Orthodontic Wires; Stress, Mechanical; Surface Properties; Tooth

Elastic bending (flexure) theory, although apparently extendable to the arch wire, incorporates assumptions that are violated in orthodontic application, and neglects several influences confined to the clinical arena. The standard elastic-bending test for orthodontic wires uses a passively straight segment of wire, and a rotational bending stiffness rather than the force-deflection ratio akin to the transverse deformation of a leveling wire is determined. In this study the transverse flexural stiffnesses of five preformed arch wires were quantified in each of three activation directions at five separate sites on simulated dental arches to which appliances were affixed. The influences of elastic moduli, numbers of strands, and interbracket distances were found to be less substantial than theory suggests. Other parameters, including wire curvature at the activation site, malalignment direction relative to that curvature, bracket-wire friction, and preactivation fit of the preformed arch to the dentition, also affected the localized, transverse, flexural stiffnesses.

Topics: Alloys; Dental Alloys; Elasticity; Humans; Malocclusion; Models, Anatomic; Models, Biological; Orthodontic Appliances; Orthodontic Wires; Stainless Steel; Stress, Mechanical; Surface Properties; Titanium; Tooth

Topics: Adolescent; Alloys; Child; Cuspid; Dental Bonding; Humans; Malocclusion; Orthodontic Appliances; Orthodontic Wires; Patient Care Planning; Stress, Mechanical; Tooth Movement Techniques

Topics: Adult; Alloys; Female; Humans; Malocclusion; Orthodontic Appliances; Orthodontic Wires; Pilot Projects; Stainless Steel; Tooth Movement Techniques

Topics: Adolescent; Adult; Alloys; Female; Humans; Male; Malocclusion; Orthodontic Wires; Orthodontics, Corrective; Tooth Movement Techniques

Topics: Adult; Alloys; Female; Humans; Malocclusion; Malocclusion, Angle Class I; Nickel; Orthodontic Appliances; Stainless Steel; Titanium

Topics: Alloys; Chemical Phenomena; Chemistry, Physical; Cuspid; Dental Alloys; Elasticity; Malocclusion; Nickel; Orthodontic Appliances; Stainless Steel; Stress, Mechanical; Titanium; Tooth Movement Techniques; Tooth, Impacted