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Effet indésirable des fils de contention collés : le « syndrome du fil » : observations, théories, conséquences cliniques : 2 e partie
Abstract
Parfois les dents se déplacent alors qu'elles semblent parfaitement stabilisées par un fil de contention, nous avions appelé ce phénomène le « syndrome du fil ».
Ce phénomène a été décrit dans toutes ses formes, aussi bien à la mandibule qu'au maxillaire dans la partie I de cet article. La littérature ne propose actuellement aucune explication mécanique pour ce phénomène. Après analyse de documents photographiques, provenant de confrères spécialistes et de notre cabinet, nous avons élaboré une théorie permettant d'expliquer la partie mécanique.
Nous évoquons deux familles d'hypothèses, non excluantes, qui peuvent se combiner.
La première hypothèse dite « intrinsèque » recense toutes les erreurs de procédures aboutissant à la pose d'un fil collé « actif ». Le fil est alors responsable des mouvements. Il agit comme un appareil orthodontique directement collé sur les dents.
La seconde hypothèse dite « extrinsèque » montre qu'une dent, collée par l'intermédiaire d'un plot de résine à un fil parfaitement passif, peut tourner si la liaison fil/colle se rompt et qu'il est soumis à une force.
La connaissance des conséquences cliniques qui en découlent permettra de lutter efficacement contre ce phénomène.
... The second theory relates to a break in the bond between the wire and the adhesive, leading to rotation of the wire, exerting force that can cause unwanted tooth movement. 7 The first theory discusses the bonding technique used to place the wire. If an indirect bonding technique has been used, whereby an impression is taken for a wire to be fabricated in the laboratory, there can be issues at the fitting appointment. ...
... It has been suggested that in order to prevent any issues during casting, the impression must be cast within 45 minutes of taking the impression. 7 An alternative would be to take a digital impression, which is becoming increasingly common, and this may overcome impressiontaking problems. ...
‘Wire syndrome’ is a phenomenon that involves fixed orthodontic retainers causing unwanted tooth movement. In severe cases, the retainer may have debonded from the teeth. This article addresses the prevalence, presentation and management of wire syndrome. This article was originally published in Orthodontic Update in July 2023 and is being reprinted in Dental Update.
CPD/Clinical Relevance: This article is relevant for general dental practitioners, periodontists and orthodontists to recognize the signs of wire syndrome and understand its multidisciplinary management.
... Extreme labial movement of the root Roussarie et al. [4,5] 2015 and 2018 Syndrome du fil Kučera et al. [9,10] 2016 Unexpected complications/X-effect, Twist-effect and non-specific complications Laursen et al. [11] 2016 ...
(1) Context and Objective: Wire syndrome (WS) refers to dental displacements which can be qualified as aberrant, unexpected, unexplained, or excessive of teeth still contained by an intact orthodontic retainer wire without detachment or fracture, leading to evolving aesthetic and/or functional consequences, both dental and periodontal. The clinical diagnosis of WS in severe cases is often easy. On the other hand, emerging cases must be detected early to stop this evolutionary process as soon as possible, as well as to effectively manage unwanted dental displacements and associated dento-periodontal tissue repercussions. The aim of this retrospective study was to understand the challenges and importance of early diagnosis, highlight the clinical gradient of WS, and clarify the key elements of diagnosis for many practitioners confronted with this type of problem. (2) Materials and Methods: Three cases of increasing complexity were described: the history of wire syndrome, a description of the key elements of its diagnosis, and the final diagnosis itself. (3) Results: Different types and locations of wire syndrome have been observed, from early form to terminal wire syndrome. The three main stages of the clinical gradient are described as follows. In the first case, wire syndrome starting on tooth 41, called the “X-effect” type, was suspected. X-effect wire syndrome on 21, X-effect wire syndrome on 41, and Twist-effect wire syndrome on 33 were diagnosed in the second case, which can be classified as an intermediate case. In the extreme clinical situation of the last case, severe and terminal wire syndrome on tooth 41, the X-effect type, was observed. (4) Conclusions: This case series presents the main stages of the clinical gradient of WS. Although in the case of early WS it is very difficult to identify and/or differentiate it from movements related to a classical relapse phenomenon, the diagnosis of terminal WS is very easy. The challenge for the practitioner is therefore to detect WS as early as possible to stop the iatrogenic process and propose a personalized treatment depending on the severity of clinical signs. The earlier WS is detected, the less invasive the treatment.
‘Wire syndrome’ is a phenomenon that involves fixed orthodontic retainers causing unwanted tooth movement. In severe cases, the retainer may have debonded from the teeth. This article addresses the prevalence, presentation and management of wire syndrome.
CPD/Clinical Relevance: This article is relevant for general dental practitioners, periodontists and orthodontists to recognize the signs of wire syndrome and understand its multidisciplinary management.
(1) Background and objective: Tooth movements described as unexplained, aberrant, unexpected, unwanted, or undesirable can occur in the presence of an intact orthodontic retention wire, without detachment or fracture. This iatrogenic phenomenon, known little or not by many practitioners, responsible for significant dental and periodontal complications, both functional and aesthetic, is called “Wire Syndrome” (WS). It is therefore considered an undesirable event of bonded orthodontic retainers, which must be differentiated from an orthodontic relapse. The objective was to perform, for the first time, a systematic review of the literature in order to define the prevalence of WS and to study its associated clinical characteristics. (2) Methods: A systematic review of the literature was performed following the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and recommendations using an electronic search strategy on four databases complemented by a manual search. All the prospective and retrospective clinical studies, including case reports and series, written in English or French, clearly mentioning the description, detection, or management of WS were included. Three independent blinding review authors were involved in study selection, data extraction, and bias assessment using the Mixed Methods Appraisal Tool (MMAT). (3) Results: Of 1891 results, 20 articles published between 2007 and 2021 fulfilled the inclusion criteria, with a globally high risk of bias since 16 articles were case report/series. The analysis of each article allowed the highlighting of WS through 13 categories, as follows: prevalence, apparition delay, patient characteristics, arch and tooth involved, families of movements, dental and periodontal consequences, type of wire, risk factors, etiologies, treatment, and preventive approach. (4) Conclusion: This systematic review of the literature elaborated a synthesis on WS, allowing general practitioners, periodontists, and orthodontists to understand this adverse event, to facilitate the diagnostic approach, and to underline preventive measures against WS. This review was registered in the International Prospective Register of Systematic Reviews (PROSPERO; number CRD42021269297).
This study compares the effect of various forearm and elbow postures on peak chuck pinch strength in sitting with armrest, sitting without armrest, and standing postures. Twenty (20) able-bodied male subjects volunteered to participate in the study. Results indicated that elbow, forearm and body postures had significant effects on pinch strength. The effect of sitting on pinch strength was significantly lower than standing. A reduction in pinch strength in these postures is documented and needs to be considered in the ergonomic design of the workplace and tools.
Background
Aim of this study was to analyze the efficacy and precision of the completely customized lingual appliance (CCLA) regarding the single tooth torque correction. The study also examined external apical root resorptions as possible side effects of torque correction and the changings of the periodontal situation.
Methods
A case series of three patients were included. The patients showed a single tooth torque problem with a gingival recession and were treated with the CCLA. Plaster casts before and after treatment and plaster casts of the set up were scanned and superimposed. Deviations between the two plaster casts were analyzed at different points of interest. Changes of the gingival recession were compared before and after treatment. Relative root resorptions were measured by the orthopantomograms. Treatment times were assessed by the records of the patients. Results were presented descriptively.
Results
The mean change of the most apical part of the root reached by the orthodontic treatment was 1.8 ± 0.3 mm. The largest deviation between set up and final model was measured on the occlusal surface of the tooth 36 with 0.8 mm. Most measurement points showed a deviation of 0.5 mm or less. The depths of the gingival recession showed a significant reduction of 4.7 mm. The widths of the gingival recession were reduced by 1.1 mm. The average relative root resorption of the corrected teeth was 2.7 ± 1.5%. The average treatment time was 13.8 ± 4.5 months.
Conclusions
This is the first study showing that the CCLA with its high precision is very effective in correcting single tooth torque problems. Orthodontic torque correction resulted in a significant reduction of gingival recessions and caused only negligible root resorptions.
Introduction The purposes of this retrospective study were to describe the types of unexpected complications associated with mandibular fixed retainers and to assess their prevalences and possible etiologic causes. Methods A total of 3500 consecutive patients (1423 male, 2077 female) treated with fixed appliances and a mandibular fixed retainer as a part of the retention protocol were screened during the retention period (2008-2013) for unexpected complications. Thirty-eight subjects (12 male, 26 female; mean age, 20.7 ± 8.9 years) with unexpected complications were identified and assigned to the unexpected complications group and compared with a randomly selected control group of 105 subjects (43 men, 62 women; mean age, 29.5 ± 9.7 years) without unexpected complications. Relationships between unexpected complications and cephalometric and clinical variables were evaluated. Results An opposite inclination of the contralateral canines (twist effect) was found in 21 subjects. In 89.5%, the left canines were tipped buccally. A torque difference of 2 adjacent incisors (X effect) was identified in 12 patients. In 5 subjects, nonspecific complications were noted. Subjects in the unexpected complications group were significantly younger at debonding (P = 0.03) and had higher mandibular plane angles (P <0.0001) and increased pretreatment ventral positions of the mandibular incisors (P = 0.029). No differences were found between the groups with regard to treatment duration, wire type, failure rate, treatment changes in incisor proclination, or intercanine distance. Conclusions Unexpected complications of mandibular fixed retainers are relatively rare. Facial divergence was identified as a possible predictor. However, the etiology is most likely multifactorial. Strong asymmetry among the patients with the twist effect suggests that the mechanical properties of retention wires may play a role and should be examined in the future.
The aim of this study was to investigate the dentofacial structure, the occlusal traits, and the bite force in subjects with advanced occlusal wear. The material comprised 54 adults, 30 men (mean = 40 years, range 16 to 61) and 24 women (mean = 28 years, range 18 to 47), most of whom had a full or near-full complement of natural teeth, and the presence of occlusal wear. Craniofacial structure was studied on lateral cephalograms. Occlusal traits were examined on study casts, these serving also for an evaluation of occlusal wear to be carried out by using an ordinal scale. Bite forces were recorded at differing force levels (maximum biting, "biting as when chewing" and "light biting") and occlusal positions. Although maximum bite force and endurance time did not differ significantly between men and women, the level of bite force was high compared with other samples. The craniofacial structure of the sample was characterized by a deviation in the vertical direction, a small angle between the mandibular-palatal planes and a small gonial angle, as compared with Swedish adult norms. No significant differences were found in anteroposterior relationships between persons with advanced wear and normal standards. The results support the hypothesis that functional hyperactivity of the masticatory system imposed increased stress on the bony structures of the craniofacial complex with possible influences on its structure.
Objectives
While permanent retention is today the method of choice to stabilize orthodontic treatment outcomes, recent studies have increasingly reported posttreatment changes in tooth position during permanent retention. We conducted this study to analyze changes in the anterior mandible, whether the changes follow an underlying movement pattern, and, aiming for a preventive strategy, whether any risk factors could be identified comparing findings with the pretreatment situations. Methods
We included 30 patients who had worn fixed Twistflex retainers (UK 3–3) extending from canine to canine in the mandible. Casts reflecting the intraoral situations before orthodontic treatment (T0), directly after completion of active therapy (T1), and 6 months later (T2) were scanned and superimposed using Imageware Surfacer software. Posttreatment changes (T2−T1) of tooth position within the retainer block were analyzed on 3D virtual models and were compared to pretreatment (T0) and treatment-related (T1−T0) findings to identify potential risk factors. ResultsAlmost all analyzed patients revealed three-dimensional changes in tooth position within the retainer block. Comparing these movements, we repeatedly found rotated retainer blocks in labio-oral direction, while the center of rotation was located at the first incisors. This pattern was associated with intercanine expansion and excessive overjet correction during orthodontic treatment. The canines underwent the most pronounced (rotational and translational) movements. Conclusions
In general permanent lingual retainers are safe but in special clinical cases retainers can induce undesired tooth movement. Risk factors seem to be intercanine expansion and excessive overjet correction during orthodontic treatment. In specific cases an additional retention device might be needed.
Retention constitutes a distinct stage of orthodontic therapy. It takes place after the conclusion of active treatment, which makes it a difficult procedure when an orthodontic appliance has been placed on the lingual surfaces of teeth. This article presents a method for fabricating and bonding a retainer during the appointment devoted to removal of the fixed appliance. This technique is a new approach that uses silicone not plaster for obtaining a working model. The step-by-step procedure is outlined in detail, from the taking of the impression to the bonding of the retainer.
The aim of this article was to assess the effect of wire adaptation on the lingual surfaces of mandibular anterior teeth with 3 types of lingual retainers on the development of vertical and labiolingual forces.
Ten retainers (canine to canine) were constructed from each of the following wires: Wildcat 0.0195-in heat-treated 3-strand twist-flex wire (GAC, Bohemia, NY); Penta-one 0.0215-in 6-strand as received; and Penta-one 0.0215-in 6-strand after heat treatment at 350°C for 4 minutes (both, Masel Orthodontics, Carlsbad, Calif). The retainers were bonded on each tooth of an acrylic resin model, and the model was installed in the Orthodontic Measurement and Simulation System. The vertical and labiolingual forces generated were measured for wire displacements up to 0.2 mm in 0.02-mm increments.
Wire displacement of 0.2 mm exerted forces as high as 1 N on the teeth. In the vertical direction, the highest force levels were recorded for the as-received Penta-one 0.0215-in and the lowest from its heat-treated counterpart. In the horizontal plane, the as-received Penta-one 0.0215-in exerted the highest forces.
The forces recorded from the lingual retainer wires during 0.2-mm simulated intrusion-extrusion and buccal-lingual movements might generate high forces that exceed 1 N and be large enough to produce unwanted tooth movement during retention. The only significant determinant of the generated forces was the amount of wire displacement and not the type of wire used in this study.