Abstract:
:As orthodontic appliances can corrode with time in the oral environment, the aim of this study was to compare the release of metal ions from new and recycled brackets immersed in buffers of different pH values over a 48 week period. To simulate commercial recycling, the stainless steel brackets were divided into two groups: new and recycled. The bases of the latter were coated with adhesive and the brackets were heat treated before being immersed in the test solution for 48 weeks. The release of nickel, chromium, iron, copper, cobalt and manganese ions was analysed by atomic absorption spectrophotometry. Differences were compared using one-way analysis of variance. The results showed that recycled brackets released more ions than new brackets (P < 0.05). Brackets immersed in solutions of pH 4 released more ions than those immersed in solutions of pH 7, and the total amount of ions released increased with time over the 48 week period (P < 0.05). This study demonstrates that both new and recycled brackets will corrode in the oral environment. To avoid clinical side-effects, metal brackets should be made more resistant to corrosion, and recycled brackets should not be used.
journal_name
Eur J Orthodjournal_title
European journal of orthodonticsauthors
Huang TH,Ding SJ,Min Y,Kao CTdoi
10.1093/ejo/26.2.171keywords:
subject
Has Abstractpub_date
2004-04-01 00:00:00pages
171-7issue
2eissn
0141-5387issn
1460-2210journal_volume
26pub_type
杂志文章abstract::The aim of this in vitro study was to compare the shear bond strength (SBS) and failure modes of a conventional resin-based composite with a recently developed amorphous calcium phosphate (ACP)-containing orthodontic composite system. Forty freshly extracted human maxillary premolar teeth were randomly divided into tw...
journal_title:European journal of orthodontics
pub_type: 杂志文章,随机对照试验
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更新日期:2010-06-01 00:00:00
abstract::The aim of this longitudinal study was to monitor patients' microbiological and clinical parameters from bracket placement up to 3 months post-treatment. Twenty-four patients (10 males and 14 females, aged 14.6 ± 1.0 years) were included in this investigation. Microbiology (sub- and supragingival), periodontal probing...
journal_title:European journal of orthodontics
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doi:10.1093/ejo/cjq032
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abstract:BACKGROUND:The Scandcleft trial is a randomized controlled trial that includes children with unilateral cleft lip and palate where registrations are standardized and therefore provides the opportunity to describe craniofacial characteristics in a very large sample of patients. OBJECTIVES:The aim of this study was to d...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjaa060
更新日期:2020-12-24 00:00:00
abstract::Occlusal traits and craniofacial morphology were studied in growing patients with Duchenne muscular dystrophy (DMD). Sixteen patients from 6 to 20 years of age were examined and compared with 16 healthy male individuals matched according to age. The dental arches and occlusal traits of both groups were analysed on den...
journal_title:European journal of orthodontics
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doi:10.1093/ejo/cjm045
更新日期:2007-10-01 00:00:00
abstract::The purpose of this study was to investigate cephalometrically, the effects of a functional appliance-headgear combination, the Elastic Bite-block (EBB). Of 50 Class II division 1 subjects who participated in this study, 30 made up the treatment group and 20 the control group. All of the selected cases exhibited mandi...
journal_title:European journal of orthodontics
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doi:10.1093/ejo/17.5.375
更新日期:1995-10-01 00:00:00
abstract::The purpose of this study was to evaluate the outcome of a scheme for provision of orthognathic surgery by examining whether patients' expectations were fulfilled as well as their opinions about the result of treatment and side-effects. Data were obtained during a pre-planned 3-year follow-up clinical examination whic...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjm081
更新日期:2008-02-01 00:00:00
abstract::The aim of this study was to statistically assess the morphological changes of the rat periodontal ligament (PDL) and its vascularity in relation to varied magnitudes of superelastic force in experimental tooth movement using nickel-titanium (NiTi) alloy wire. Forces of 0.8, 1.6, 4, 8, and 18 g were applied to the upp...
journal_title:European journal of orthodontics
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更新日期:2009-02-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjq089
更新日期:2011-06-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:1997-04-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjx072
更新日期:2018-05-25 00:00:00
abstract::Mandibular advancement splints (MASs) are used to advance the mandible forward in patients with sleep-disordered breathing. The conventional rigid MAS restricts the movement of the mandible, and this immobility sometimes produces discomfort, including temporomandibular disorders. A simple method for fabricating a mobi...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjp040
更新日期:2009-12-01 00:00:00
abstract::The analysis of the non-linear and time-dependent viscoelasticity of the periodontal ligament (PDL) enables a better understanding of the biomechanical features of the key regulator tissue for tooth movement. This is of great significance in the field of orthodontics as targeted tooth movement remains still one of the...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjs103
更新日期:2013-12-01 00:00:00
abstract::The location of the centre of resistance (CR) of various consolidated units of maxillary anterior teeth was determined in this study using human autopsy material. The units studied consisted of two central incisors, four incisors, and six anterior teeth. When horizontal forces were applied the CR for the two- and six-...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/13.6.452
更新日期:1991-12-01 00:00:00
abstract:BACKGROUND/OBJECTIVE:Facial asymmetry is very common in adult class III patients; however, the degree of facial asymmetry in growing class III subjects has been poorly investigated. Therefore, the aim was to assess the degree of facial asymmetry of growing class III subjects and to compare it with a sample of growing s...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjt069
更新日期:2014-08-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/oxfordjournals.ejo.a035984
更新日期:1989-05-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjr043
更新日期:2012-08-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjq163
更新日期:2012-02-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/26.4.443
更新日期:2004-08-01 00:00:00
abstract:BACKGROUND:Cervical headgear (CH) is a commonly used orthodontic appliance and its dentoalveolar changes are known. However, the effects related to gender and timing have gained less attention. OBJECTIVES:To examine dimensions of dental arches among children with Class II occlusion without posterior mandibular rotatio...
journal_title:European journal of orthodontics
pub_type: 杂志文章,随机对照试验
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更新日期:2019-11-15 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
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更新日期:2012-06-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
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更新日期:2020-01-27 00:00:00
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journal_title:European journal of orthodontics
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更新日期:2014-10-01 00:00:00
abstract::Seven-hundred-and-ninety-one 15-year-olds were subjected to an anamnestic and clinical examination of craniomandibular disorders. These individuals had been examined at the age of 12 years and this is one section of an extensive longitudinal investigation into the effects of malocclusion, and the effectiveness of orth...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/14.2.152
更新日期:1992-04-01 00:00:00
abstract::The aims of this study were to provide a description of the craniofacial morphology of Singaporean Chinese children and to compare gender differences. Lateral cephalometric radiographs were obtained of 81 Singaporean Chinese children (31 boys and 50 girls; mean age 12.7 and 12.5 years, respectively, standard deviation...
journal_title:European journal of orthodontics
pub_type: 杂志文章
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更新日期:2004-12-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
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更新日期:2015-12-01 00:00:00
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journal_title:European journal of orthodontics
pub_type: 杂志文章
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更新日期:2018-11-30 00:00:00
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pub_type: 杂志文章,随机对照试验
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更新日期:2010-02-01 00:00:00
abstract::The aim of this study was to compare standard plaster models with their digital counterparts for the applicability of the Index of Complexity, Outcome, and Need (ICON). Generated study models of 30 randomly selected patients: 30 pre- (T(0)) and 30 post- (T(1)) treatment. Two examiners, calibrated in the ICON, scored t...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/cjn077
更新日期:2009-06-01 00:00:00
abstract::Class II elastics are usually employed in the treatment of excessive overbite and overjet with the Begg technique. The effect of Class II elastics on bite opening and the extent of such an effect is uncertain. This article, based on measurements of 30 cases, illustrates that the effect of the vertical component of for...
journal_title:European journal of orthodontics
pub_type: 杂志文章
doi:10.1093/ejo/14.4.280
更新日期:1992-08-01 00:00:00