Abstract：
:The viscoelastic behaviour of prototype composite orthodontic archwires was evaluated using a bend stress relaxation test. Archwires having 10 different volume fractions of reinforcement were subjected to constant bending radii in a water bath at 37 degrees C for time periods of up to 90 days. The wires were subsequently released and left unconstrained for the same testing conditions. Creep-induced changes in the unconstrained bending radii of the wires were measured at specific times during both phases (stress relaxation and recovery) of the test. The statistical analysis showed that stress relaxation behaviour was strongly correlated with the archwire reinforcement level. The final relaxation varied, with decreasing reinforcement, from 2 to 8 per cent. Archwire recovery was not correlated with reinforcement level, and revealed a final viscous loss of only 1 per cent. The relaxed elastic moduli in bending of the composite wires were similar to the elastic moduli in bending of several conventional orthodontic archwire materials. Losses that were associated with the viscoelastic behaviour varied with decreasing reinforcement level from 1.2 to 1.7 GPa. Because these modulus losses were minimal, each archwire retained sufficient resilience to be applicable to the early and intermediate stages of orthodontic treatment.
journal_name
Eur J Orthodjournal_title
European journal of orthodonticsauthors
Zufall SW,Kusy RPdoi
10.1093/ejo/22.1.1keywords:
subject
Has Abstractpub_date
2000-02-01 00:00:00pages
1-12issue
1eissn
0141-5387issn
1460-2210journal_volume
22pub_type
杂志文章abstract：:This retrospective study examined the occurrence of congenitally missing permanent teeth and the need for dental treatment in the Regensburg University Medical Centre of Eastern Bavaria. Using a dental administration software tool, a total of 1442 patients who presented for orthodontic treatment between 1994 and 2006 ...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjq021
更新日期：2011-02-01 00:00:00
abstract：:The aim of the present study was to compare patient, parent and clinician perceived need for orthodontic treatment in relation to normative orthodontic treatment need as measured by the Index of Orthodontic Treatment Need (IOTN). A prospective cross-sectional study was designed to address this aim. The sample comprise...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/26.3.265
更新日期：2004-06-01 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：Aim:The aim of this study was to describe hard and soft tissue changes after mandibular advancement surgery and to investigate the possible differences between Class II facial patterns. Materials and methods:Lateral cephalograms of 109 patients who underwent combined orthodontic treatment and bilateral sagittal split ...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjx003
更新日期：2017-10-01 00:00:00
abstract：OBJECTIVES:Assess facial asymmetry in subjects with unilateral cleft lip (UCL), unilateral cleft lip and alveolus (UCLA), and unilateral cleft lip, alveolus, and palate (UCLP), and to evaluate which area of the face is most asymmetrical. METHODS:Standardized three-dimensional facial images of 58 patients (9 UCL, 21 UC...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cju104
更新日期：2015-12-01 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 purpose of this work was to examine whether the clinical eruption of the permanent first molars and incisors is affected by pre-term birth. The data applied to 328 prematurely born white and black children and 1804 control children who participated in the Collaborative Perinatal Project (USA) in the early 1960s an...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/25.3.293
更新日期：2003-06-01 00:00:00
abstract：:The purpose of the present investigation was to determine the long-term prognosis of autotransplanted premolars with respect to periodontal healing. The subjects consisted of 195 patients aged 7 to 35 years, with a total of 370 autotransplanted all operated and followed with a standard technique. The observation perio...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/12.1.25
更新日期：1990-02-01 00:00:00
abstract：:This study was designed to explore a new method for the assessment of dental crowding from study models, which would be both valid and reproducible. This was then tested against two previously reported strategies. A single examiner compared the following methods: visual examination, brass wire/callipers, and a reflex ...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/19.5.543
更新日期：1997-10-01 00:00:00
abstract：:The aim of this study was to investigate potential occurrence of bacteremia in orthodontic patients after removal of miniscrews.The study group comprised 30 healthy subjects (17 males, 13 females) with a mean age of 24.1 years treated with self-ligating fixed appliances and mini-implant anchorage. Two 20 ml venous blo...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjs099
更新日期：2014-02-01 00:00:00
abstract：:The effects of the van Beek activator in the correction of Class II, division 1 malocclusions were studied in 39 children, aged 9-13 years (median 11 years), and compared with the effects of treatment with an activator according to Herren and with those of an activator-headgear combination. Profile cephalograms were m...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/20.4.389
更新日期：1998-08-01 00:00:00
abstract：Objective:The aim of this in vitro study was to evaluate the progressive development of surface microdamage produced following the insertion of orthodontic miniscrews (OMs) into 1.5 mm thick porcine tibia bone using maximum insertion torque values of 12 Ncm, 18 Ncm, and 24 Ncm. Methods:Aarhus OMs (diameter 1.5 mm; len...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjx026
更新日期：2018-01-23 00:00:00
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
doi：10.1093/ejo/cjp115
更新日期：2010-06-01 00:00:00
abstract：:Clinical outcomes in children born with a cleft lip and palate (CLP) have been an area of interest for orthodontists for a number of years. Whilst tools for measurement of these outcomes are available, there is no widely accepted measure of initial cleft severity and no known quantitative indices. Therefore, the poten...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/22.1.93
更新日期：2000-02-01 00:00:00
abstract：:The effect of protruded mandibular function on the maxilla and zygoma was studied in young unilaterally condylectomized growing rats. Forty-eight-4-week-old rats were divided into two experimental and two control groups as follows: group A, 12 animals unilaterally condylectomized on the right side; the mandible was al...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/19.2.205
更新日期：1997-04-01 00:00:00
abstract：:A retrospective cephalometric study was made of the hard tissue changes in a group of 90 Class III, Skeletal III children, diagnosed as suitable for treatment by orthodontic means alone. Thirty-two were treated by a combination of upper incisor proclination and headgear to an intact mandibular dentition (Group 1), whi...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/13.3.212
更新日期：1991-06-01 00:00:00
abstract：:The aim of this study was to compare the effects of the Gjessing (PG) retraction spring used with and without the zygoma anchorage system (ZAS) on canine retraction. Thirty patients, with an Angle Class I or Class II malocclusion, whose upper first premolars were scheduled for extraction, were divided into two equal g...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjp167
更新日期：2010-10-01 00:00:00
abstract：:The aim of this laboratory-based study was to investigate the effects of different combinations of tip and torque upon friction between an orthodontic bracket and archwire using a specially made jig. Victory Twin Series upper premolar brackets (3M Unitek) were mounted on a jig, which allowed tip and torque values in t...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjn017
更新日期：2008-10-01 00:00:00
abstract：:A high prevalence of cervical vertebrae anomalies (CVA) has been recently associated with various malocclusions. Our aim was to study the prevalence of CVA on lateral cephalograms in Class II subjects and to compare the findings with those obtained from cone beam computed tomography (CBCT). Standardized cephalograms o...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjq192
更新日期：2012-04-01 00:00:00
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：: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
abstract：:It was the aim of this study to investigate radiologically the distraction site in the gonial angle area after three different protocols of unidirectional mandibular distraction in sheep. Bilateral mandibular distraction was performed in nine sheep, and one other sheep served as a sham-operated control. In the nine ex...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/25.2.127
更新日期：2003-04-01 00:00:00
abstract：:It was the aim of the present study to cast light on the role of the mandible in relation to head posture and airway space by evaluating patients before and after surgical correction of mandibular prognathism. The material comprised standardized profile cephalograms of 52 patients with mandibular prognathism. All pati...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/oxfordjournals.ejo.a035962
更新日期：1989-02-01 00:00:00
abstract：:Various investigations have mentioned the use of a bonded maxillary expansion appliance. It was postulated that a full coverage of the occlusal surfaces by acrylic would remove interferences during the lateral displacement of the two maxillary bones and would lessen the resistance to maxillary expansion. The first obj...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/oxfordjournals.ejo.a035967
更新日期：1989-02-01 00:00:00
abstract：:The present review summarizes two decades of published and unpublished studies on normal and pathological development of sella turcica and pituitary gland in humans. The pathological conditions are studied in known genotype deviations, syndromes, and other malformations. The studies include histological analyses of hu...
journal_title：European journal of orthodontics
pub_type： 杂志文章,评审
doi：10.1093/ejo/cjs091
更新日期：2015-02-01 00:00:00
abstract：:The purpose of this study was to demonstrate the advantage of the finite helical axis (FHA) system in the biomechanical analysis of orthodontic tooth movement by comparing it with the rectangular coordinate (XYZ) system. Ten patients (6 females and 4 males, mean age 23 years 7 months) were selected. Maxillary canine r...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjm061
更新日期：2007-12-01 00:00:00
abstract：:The persistence of childlike deglutition after the replacement of deciduous teeth is described as atypical deglutition. This condition has been attributed to sucking action without nutritive purposes, use of a feeding bottle, oral respiration, and anatomical abnormalities. Among the possible anatomical alterations, th...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjq167
更新日期：2012-02-01 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
doi：10.1093/ejo/26.6.605
更新日期：2004-12-01 00:00:00
abstract：:The purpose of this laboratory study was to assess the potential cleaning efficacy of nine different toothbrushes around brackets in vitro. Standard and Mini Diamond brackets were fixed on coloured teeth in a special model, coated with white titanium oxide, brushed in a machine with different manual toothbrushes (thre...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/cjn070
更新日期：2009-02-01 00:00:00
abstract：:Many animal experiments dealing with function-form interaction and mandibular condylar growth have utilized hyperpropulsion of the animal's mandible. Numerous hyperpropulsive appliances have been described in the literature. However, there are significant discrepancies between reported results which are most likely du...
journal_title：European journal of orthodontics
pub_type： 杂志文章
doi：10.1093/ejo/19.1.1
更新日期：1997-02-01 00:00:00
