Assessment of Ions released from Three Types of Orthodontic Brackets immersed in Different Mouthwashes: An in vitro Study

Abstract

Aim: Herbs are used widely in medicine. The purpose of the present study was to assess the ion release from gold-plated orthodontic bracket compared with other stainless steel brackets, and based on the findings of the study, the orthodontists can choose the most biocompatible brackets and mouthwashes useful in the clinical practice. Materials and methods:A total of 150 orthodontic brackets from Orthotechnology™ Company, USA (50 stainless steel one-piece brackets, 50 stainless steel two-piece brackets, and 50 gold brackets) were immersed in four mouthwashes in addition to distilled water. Ten of each type of brackets in every media were immersed under 37°C for 45 days. Ions released in these mouthwashes were measured, and comparisons among different bracket types and among various mouthwashes were done by one-way analysis of variance (ANOVA) and then with Games-Howell tests.Results: Increased amounts of ions released in herbal mouthwashes were recorded in gold and two-piece brackets in comparison with one-piece stainless steel brackets. Conclusion:Herbal mouthwashes must be used with caution as they showed an increased amount of ions released in comparison with chlorhexidine. One-piece stainless steel bracket system is the most compatible bracket type, as they released the least amount of ions.Clinical significance: One-piece stainless steel brackets are better than two-piece brackets in terms of ions released.

Effect of Mouthwashes on Frictional Properties of Gold-plated and Ordinary Stainless Steel Orthodontic Brackets

“…30 Among gold-plated brackets subgroups, gold-plated brackets immersed in aloe vera with fluoride showed the lowest frictional forces making aloe vera with fluoride mouthwash to be the most recommended mouth rinse with this bracket type. This was interesting since fluoride showed higher corrosive ability in previous studies 24,27 while the highest static friction was recorded in goldplated brackets immersed in chlorhexidine group, this could be consistent with other researches describing the corrosive ability of chlorhexidine. 24,31 Considering Votion brackets subgroups, the highest static friction was measured in aloe-vera mouthwash group.…”

“…Concerning brackets types, gold-plated brackets showed higher frictional forces than stainless steel brackets in all immersed and control groups. In spite of the presence of the exterior protective gold layer which is plated originally on one piece casted steel bracket to enhance resistant to wear, chipping and peeling, 27 results elucidating that this layer was not stable under the mouth rinses being used in the present study.…”

“…In one recent study 27 that examined the ions release from stainless steel and gold-plated brackets after immersion in different herbal mouthwashes, no subtle pattern between bracket types and concentration of cations released could be seen, and consequently this could not be clear-cut cause and effect relationship, instead results might be due to the effect of cold working (bending, shearing, punching, etc.). A non-uniform deformation could be happened during the manufacturing process of gold-plated brackets, moreover; unequal cooling from high temperature lead to internal structure rearrangements involving volume change causing internal stress that may produce cracks of the outer protective layer, accelerating corrosion 28 and consequently increase the surface roughness which is a critical variable in determining friction since the smoothest surface is expected to yield the lowest friction and vice versa.…”

“…This is consistent with another study compared ion release among mouthwashes. 27 Aloe-Vera herb showed the highest manganese and copper ions which are considered as main components of stainless steel alloy, detecting surface corrosion of the metal and consequently increase surface roughness and friction. These results disagreed with Singh 32 who claimed that herbal mouth rinses showed inhibition efficiency of corrosion lied between 22% and 73% at different concentrations.…”

Evaluation of Salivary Nickel, Chromium and Iron Ions in Patients Treated with Fixed Orthodontic Appliances in Vivo Study

“…The first is the construction procedure, which consists of the type of alloy and the nature of the metals used, the second is environmental factors, like mechanical factors, time of the day, stress, diet, salivary flow rate, health and psychosomatic condition of the person. 9,10,11 The result of most studies on the amounts of metal ions released from orthodontic alloys had displayed that they were lower than the recommended daily dietary intakes of Ni and Cr, this might be a false positiveness of safety, as long as chronic low levels of metal ions can change cellular metabolism and morphology, and lead to inflammation and even DNA instability. In addition, some in-vivo researches showed biologic toxicity in orthodontic patients.…”