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Seide M, Kruse T, Graf I, Bourauel C, Lapatki BG, Jäger R, Braumann B. Inadvertent side effects of fixed lingual retainers : An in vitro study. J Orofac Orthop 2024; 85:223-232. [PMID: 36369385 PMCID: PMC11035406 DOI: 10.1007/s00056-022-00432-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 09/10/2022] [Indexed: 11/13/2022]
Abstract
PURPOSE To better understand the side effects of fixed lingual retainers by means of an in vitro study in a two-tooth model determining the three-dimensional (3D) force-moment components acting at adjacent teeth combined with different composite-wire interfaces. METHODS Triple-stranded round retainer wires were embedded in cured disks of flowable composite. At one side the composite-wire interface was untreated and checked to be absolutely fix. At the other side the composite-wire interface was configured as either an isolated compound with (1) petroleum jelly coating, or an adhered compound with (2) no manipulation, (3) ethanol degreasing or (4) ethanol degreasing and rectangular bending of the wire ends. The 3D force-moment components were registered, while the intertooth distance was increased in steps of 0.01 mm leading to increasing tension of the wire. Measurements were repeated after artificially aging the specimens. RESULTS Retainer wire specimens with adhered compound (2, 3, 4) showed negative vestibulo-oral moments ranging maximally each between -0.3 and -0.9 Nmm in opposite direction to positive moments of 1.9 Nmm for specimens with isolated compound 1. Significant tipping moments occurred in the group with isolated compound at lower forces than in those groups with adhered compound. Similar effects were observed after artificial aging. CONCLUSION Side effects emerge under specific circumstances: an altered adhesive compound combined with the presence of oral forces. Compounds with lost adhesion at the composite-wire interface showed rotational moments in the direction of the wire windings even during low tensile forces similar to those that may occur in clinical settings. Opposite rotational moments leading to unwinding of the wire may occur in cases with adhered compounds at higher tensile forces. Utilization of round triple-stranded retainer wires without bent ends are of higher risk to induce inadvertent side effects.
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Affiliation(s)
- Marlen Seide
- Faculty of Medicine and University Hospital Cologne, Department for Orthodontics, University of Cologne, Kerpener Street 32, 50931, Cologne, Germany
| | - Teresa Kruse
- Faculty of Medicine and University Hospital Cologne, Department for Orthodontics, University of Cologne, Kerpener Street 32, 50931, Cologne, Germany.
| | - Isabelle Graf
- Faculty of Medicine and University Hospital Cologne, Department for Orthodontics, University of Cologne, Kerpener Street 32, 50931, Cologne, Germany
| | - Christoph Bourauel
- Oral Technology, University Hospital Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
| | - Bernd G Lapatki
- Department of Orthodontics, Center of Dentistry, University of Ulm, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Rudolf Jäger
- Department of Orthodontics, Center of Dentistry, University of Ulm, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Bert Braumann
- Faculty of Medicine and University Hospital Cologne, Department for Orthodontics, University of Cologne, Kerpener Street 32, 50931, Cologne, Germany
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Çokakoğlu S, Adanur-Atmaca R, Çakır M, Öztürk F. Stability and failure rate during 3 years of fixed retention: A follow-up of an randomized clinical trial on adolescents with four different lingual retainers. Orthod Craniofac Res 2024; 27:251-258. [PMID: 37786933 DOI: 10.1111/ocr.12714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/11/2023] [Accepted: 09/12/2023] [Indexed: 10/04/2023]
Abstract
OBJECTIVE To evaluate stability outcomes and failure rates associated with four types of lingual retainers: (1) dead-soft wire, (2) multistrand stainless steel (SS) wire, (3) CAD/CAM nitinol, and (4) connected bonding pads (CBPs) after 3 years of retention. METHODS This study enrolled 96 patients (66 females, 30 males) with a median age of 19 years with four types of lingual retainers: (1) 0.016 × 0.022-inch dead-soft wire, (2) 0.0215-inch five-strand SS wire, (3) 0.014 × 0.014-inch CAD/CAM nitinol wire, and (4) CBPs. The irregularity index, intercanine distances, and arch lengths were obtained and used to evaluate mandibular stability. Failure rates were also assessed during this study. Data were statistically analysed. RESULTS Irregularity increased, whereas intercanine width and arch length decreased after 3 years of retention. The greatest irregularity was associated with the CBPs and the least with the CAD/CAM retainers. Changes in stability measurements were significantly higher in the dead-soft wire and CBPs than those in the CAD/CAM nitinol and multistrand SS wires. Parallel to these changes, the frequency of failure yielded similar results with the same significance between the groups. The failure rate of CBPs, in contrast to the CAD/CAM nitinol and multistrand SS wires, was significantly higher in the right quadrant (P < .05). CONCLUSION After taking the 3-year results into consideration, CAD/CAM nitinol and multistrand SS wires were found to be more successful than the others in maintaining mandibular stability. The most failures were observed with CBPs after 3 years of retention.
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Affiliation(s)
- Serpil Çokakoğlu
- Department of Orthodontics, Faculty of Dentistry, Pamukkale University, Denizli, Turkey
| | | | - Merve Çakır
- Department of Orthodontics, Faculty of Dentistry, Pamukkale University, Denizli, Turkey
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Kumar SO, Srinidhi S, Visshishta J, Sirisha S, Ranganathan S, Priya K, Moulvi S, Mani B. Evaluation of Orthodontic Retention Protocol among Orthodontist and General Dentist-A Cross-Sectional Survey. JOURNAL OF PHARMACY AND BIOALLIED SCIENCES 2024; 16:S1588-S1590. [PMID: 38882740 PMCID: PMC11174164 DOI: 10.4103/jpbs.jpbs_1099_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/02/2023] [Accepted: 12/07/2023] [Indexed: 06/18/2024] Open
Abstract
Aim The current study was conducted with the aim of evaluating the retention protocol followed by orthodontists in India. Material and Methods A cross-sectional web-based questionnaire survey was carried out to evaluate the retention protocol. To determine the sample size, a pilot study was carried out, and the final sample arrived was 250 subjects. The current study's inclusion criteria took into account those who had finished their BDS&MDS (Orthodontist). Results The data were statistically examined when the surveys were received and completed. The choice for fixed retainers was 67.4%. Retainer wear time preferences ranged widely, with 60% preferring 12-18 hours. The initial post-retention check appointment was planned by the majority of orthodontists (47.6%) within the next three months. Recall appointments for retention checks were only planned by the majority of orthodontists (56.3%) once every three months. Regular involvement by patients at their retention check appointments was (38%). Conclusion The most commonly used and preferred type of retainer is fixed retainer, and dentist preferences range around 12-18 hours of wear time. Furthermore, the duration of the retainer wear preferred by most orthodontists/dentists is 10 months to 2 years.
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Affiliation(s)
- S Ojass Kumar
- Department of Orthodontics and Dentofacial Orthopaedics, Malla Reddy Dental College for Women. Hyderabad, Telangana, India
| | - S Srinidhi
- Department of Public Health Dentistry, Karpaga Vinayaga Institute of Dental Sciences, Chengelpattu, Chennai, Tamil Nadu, India
| | - J Visshishta
- Department of Orthodontics and Dentofacial Orthopaedics, Mallareddy Institute of Dental Sciences, Hyderabad, India
| | - Sapasetty Sirisha
- Private Practitioner, Department of Orthodontics and Dentofacial Orthopaedics, Hyderabad, India
| | - Sukanya Ranganathan
- Department of Orthodontics and Dentofacial Orthopedics, Madha Dental College and Hospital, Madha Nagar, Kundrathur, Chennai, Tamil Nadu, India
| | - K Priya
- Department of Orthodontics and Dentofacial Orthopedics, Adhiparasakthi Dental College and Hospital, Melmaruvathur, Chennai, Tamil Nadu, India
| | - Smm Moulvi
- The FACE OMFS Centre, Chennai, Tamil Nadu, India
| | - Bhuvaneswari Mani
- Department of Orthodontics and Dentofacial Orthopaedics, Karpaga Vinayaga Institute of Dental Sciences, Chengelpattu, Chennai, Tamil Nadu, India
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Kanizaj Ugrin S, Špalj S. Comparison of efficacy of thermoplastic retainer with round and rectangular bonded lingual wire retainer in the mandible two years after orthodontic treatment: a randomised controlled trial. Clin Oral Investig 2024; 28:183. [PMID: 38424224 DOI: 10.1007/s00784-024-05572-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 02/21/2024] [Indexed: 03/02/2024]
Abstract
OBJECTIVE To analyse three protocols in maintaining the stability of orthodontic therapy results and their effect on gingival health. MATERIALS AND METHODS Sixty-six subjects (pre-therapeutic age 11-18 years; 68% female) randomly allocated into three retention groups of equal size were analysed. The first group had a 0.673 × 0.268 mm (0.027 × 0.011 inches) rectangular braided steel retention wire bonded to the lingual surfaces of all mandibular teeth from canine to canine, and the second group had a 0.406 mm (0.016 inches) round twisted steel wire. The third group was the control, without wires, and only with vacuum-formed retainers. All three groups had vacuum-formed removable retainers in the maxilla. The frequency of wire detachment/breakage/loss of retainer, the occurrence of crowding of mandibular incisors, and changes in intercanine width and gingival health were monitored. RESULTS Incidence and severity of relapse differed between groups (p = 0.001 and 0.049) being most common in the removable retainer group (incidence 68.2%; severity 0.7 ± 1.0 mm), followed by the round wire group (36.4%; 0.5 ± 1.2 mm) and rectangular wire group (13.6%; 0.1 ± 0.1 mm). The intercanine width decreased more without a bonded retainer (incidence 68.2%; severity 0.5 ± 0.7 mm) and with the round wire more (45.5%; 0.5 ± 0.7 mm) than with the rectangular (27.3%; 0.1 ± 0.3 mm). The difference was significant for incidence (p = 0.025), but not severity. Detaching of the wires/breakage/loss of retainer was similar. There were no significant differences in the accumulation of biofilm, calculus and gingivitis between appliances. CONCLUSION A rectangular wire is the most effective in retention, and the impact of retention appliances on gingival health is similar. TRIAL REGISTRATION ClinicalTrials.gov, NCT05121220. Registered 02 October 2021 - Retrospectively registered. CLINICAL RELEVANCE Studying guidelines for reducing relapse, proper use of materials and appliances, the behavior of retention wires according to their profile in the retention phase, and possibilities of maintaining oral health will contribute to improving the stability of orthodontic therapy results.
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Affiliation(s)
- Silvija Kanizaj Ugrin
- Orthodontic Clinic Orthonova, Zagreb, Croatia.
- School of Dental Medicine, University of Zagreb, Zagreb, Croatia.
| | - Stjepan Špalj
- Faculty of Dental Medicine, University of Rijeka, Rijeka, Croatia
- Faculty of Dental Medicine and Health, J. J. Strossmayer University of Osijek, Osijek, Croatia
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Koller S, Niederau C, Azraq I, Craveiro RB, Knaup I, Wolf M. Low translational and rotational movements with 2-point stainless-steel retainers over a period of 1 and 3 years. J Orofac Orthop 2023:10.1007/s00056-023-00505-y. [PMID: 38153533 DOI: 10.1007/s00056-023-00505-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 10/25/2023] [Indexed: 12/29/2023]
Abstract
OBJECTIVES Long-term stabilization of orthodontic treatment outcomes is an everyday challenge in orthodontics. The use of permanently attached lingual retainers has become gold standard. However, in some cases, patients with fixed lingual retainers show retainer-associated side effects. Aiming to reduce these side effects, clinical knowledge about how tooth and arch form stability adaption takes place over time is important to improve long-term retention protocols. Therefore, the present study aimed to investigate occlusion stability and risks for a newly developing malocclusion in a time-dependent manner in patients being treated with permanent 2‑point steel retainers. MATERIALS AND METHODS In this retrospective cohort study, a total of 66 consecutive patients with round stainless-steel retainers were analyzed for postorthodontic occlusion changes after 1 year (group 1, n = 33) and 3 years (group 2, n = 33). Digital Standard Tessellation Language (STL) datasets of the lower jaw were obtained before retainer insertion (T0), and after a 1- (T1) or 3‑year (T2) retention period. Using superimposition software, T1 and T2 situations were compared to T0 regarding rotational and translational changes in tooth positions in all three dimensions. RESULTS Occlusion changes were low in both groups. The investigated lower canines were nearly stable in the 1‑ and 3‑year group, although a retention-time-dependent increase in tooth position change of the central and lateral incisors could be observed. CONCLUSION The present data provide evidence for time-dependent development of posttherapeutic occlusal adaption limited to central and lateral incisors in patients treated with a 2-point retainer. The observed occlusal changes should be interpreted as an occlusal adaption process rather than severe posttreatment changes associated with the orthodontic retainer.
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Affiliation(s)
- Sarah Koller
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
- Orthodontic Specialist Practice Dr. Inge Kiegel-Koller, Bergheim, Germany
| | - Christian Niederau
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany.
| | - Irma Azraq
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Rogerio Bastos Craveiro
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Isabel Knaup
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Michael Wolf
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
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Koller S, Craveiro RB, Niederau C, Pollak TL, Knaup I, Wolf M. Evaluation of digital construction, production and intraoral position accuracy of novel 3D CAD/CAM titanium retainers. J Orofac Orthop 2023; 84:384-391. [PMID: 35357509 PMCID: PMC10587025 DOI: 10.1007/s00056-022-00393-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 02/22/2022] [Indexed: 10/18/2022]
Abstract
OBJECTIVES New opportunities have arisen to manufacture three-dimensional computer-aided design/computer-aided manufacturing (3D CAD/CAM) retainers from titanium blocks by digital cutting technology. These novel technologies need to fulfill requirements regarding digital planning and position accuracy. The aim of the present study was to investigate the digital construction, the CAD/CAM production and the intraoral positioning accuracy of custom-manufactured novel 3D CAD/CAM titanium retainers. MATERIALS AND METHODS A total of 37 prime4me® RETAIN3R (Dentaurum, Ispringen, Germany) retainers were inserted to stabilize the upper anterior front teeth. Following insertion, an intraoral scan was used to record the position. The intraoral position was compared to the virtual setup using 3D superimposition software. Measurement points were evaluated in all three dimensions (horizontal, sagittal and vertical planes). Data were analyzed using Kruskal-Wallis test followed by Dunn's multiple comparison test. RESULTS A total of 185 measurements were performed. The horizontal plane and the sagittal plane demonstrated a high level of positioning accuracy between the planned and the intraoral position. Statistically significant deviations between the preceding virtual setup and the intraoral situation were observed in the vertical dimension. Within the retainer, the intraoral positioning accuracy decreased for the measurement points in the direction of the distal retainer segment. CONCLUSION Based on the results, the present study shows a high level of congruence between the 3D virtually planning and the final intraoral position of the fabricated novel 3D CAD/CAM titanium retainers.
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Affiliation(s)
- S Koller
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
| | - R B Craveiro
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany.
| | - C Niederau
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
| | - T L Pollak
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
| | - I Knaup
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
| | - M Wolf
- Department of Orthodontics, Dental Clinic, University Hospital RWTH Aachen, Pauwelsstr. 30, 52074, Aachen, Germany
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Charavet C, Israël N, Vives F, Dridi SM. Importance of Early Detection of Wire Syndrome: A Case Series Illustrating the Main Stages of the Clinical Gradient. Clin Pract 2023; 13:1100-1110. [PMID: 37736934 PMCID: PMC10514803 DOI: 10.3390/clinpract13050098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 08/28/2023] [Accepted: 09/07/2023] [Indexed: 09/23/2023] Open
Abstract
(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.
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Affiliation(s)
- Carole Charavet
- Département d’Orthodontie, Faculté de Chirurgie-Dentaire, Université Côte d’Azur, 06300 Nice, France;
- UEC d’Orthodontie, Institut de Médecine Bucco-Dentaire, Centre Hospitalier Universitaire de Nice, 06300 Nice, France
- Laboratoire de Microbiologie Orale, Immunothérapie et Santé (MICORALIS) UPR7354, Faculté de Chirurgie-Dentaire, Université Côte d’Azur, 06300 Nice, France
| | - Nathan Israël
- Département d’Orthodontie, Faculté de Chirurgie-Dentaire, Université Côte d’Azur, 06300 Nice, France;
- UEC d’Orthodontie, Institut de Médecine Bucco-Dentaire, Centre Hospitalier Universitaire de Nice, 06300 Nice, France
| | | | - Sophie-Myriam Dridi
- Département de Parodontologie, Faculté de Chirurgie-Dentaire, Université Côte d’Azur, 06300 Nice, France;
- UF de Parodontologie, Institut de Médecine Bucco-Dentaire, Centre Hospitalier Universitaire de Nice, 06300 Nice, France
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Jepsen K, Sculean A, Jepsen S. Complications and treatment errors involving periodontal tissues related to orthodontic therapy. Periodontol 2000 2023; 92:135-158. [PMID: 36920050 DOI: 10.1111/prd.12484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 10/25/2022] [Accepted: 01/04/2023] [Indexed: 03/16/2023]
Abstract
In this review, typical clinical complications involving periodontal tissues are illustrated that can be encountered in conjunction with orthodontic therapy (OT). Special considerations are given for various clinical scenarios, such as the patient presenting in periodontal health, with periodontitis, or with mucogingival conditions. While some of the complications are seen as common side effects of OT, other, more severe, problems that could have been avoided may be viewed as treatment errors. Recommendations are made on how to prevent these complications, based on the currently available evidence, on clinical practice guidelines, and on expert opinion. In conclusion, while there are several areas in which OT can have unwanted adverse effects on periodontal/mucogingival conditions, there is also great potential for synergies, offering opportunities for close cooperation between the two specialties (periodontics and orthodontics) for the benefit of patients affected by tooth malpositioning and/or periodontal or mucogingival problems.
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Affiliation(s)
- Karin Jepsen
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, Bonn, Germany
| | - Anton Sculean
- Department of Periodontology, University of Bern, Bern, Switzerland
| | - Søren Jepsen
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, Bonn, Germany
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Chacón-Moreno A, Ramírez-Mejía MJ, Zorrilla-Mattos AC. Relapse and inadvertent tooth movement post orthodontic treatment in individuals with fixed retainers: A review. REVISTA CIENTÍFICA ODONTOLÓGICA 2022; 10:e116. [PMID: 38389556 PMCID: PMC10880701 DOI: 10.21142/2523-2754-1003-2022-116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 09/06/2022] [Indexed: 02/24/2024] Open
Abstract
Orthodontists must fully inform patients about the implications of orthodontic treatment and the subsequent need for retention. This review provides an update on relapse, unwanted movements and different factors that can cause loss of stability following orthodontic treatment. Since it is difficult to predict which patients will present some degree of loss of stability after treatment, it is important that they be treated as if they have a high potential for relapse. The present review included a bibliographic search in the main sources of scientific review including Medline via PubMed, Scopus and the Cochrane library. The search strategy was carried out until May 5, 2022. Only 34 studies fulfilling the selection criteria. Our results showed that maintaining teeth in the correct position following orthodontic treatment is a great challenge for orthodontists. The etiology of relapse is complex and not yet clearly established. Its origin is attributed to factors such as the time of gingival and periodontal tissue reorganization and changes produced by growth, compromising the stability of the results achieved with orthodontic treatment. The retention phase is necessary after orthodontic treatment to avoid relapse or loss of the occlusion results obtained. However, fixed retainers may induce unwanted tooth movement that may occur despite these retainers being attached and intact. There is currently no consensus among orthodontists regarding the ideal type of wire for fixed containment. We concluded that post-orthodontic treatment relapse is the result of a regression towards the original malocclusion. However, changes in the position of the teeth can also occur, which are considered as unwanted movements and have a multifactorial origin.
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Affiliation(s)
- Alicia Chacón-Moreno
- School of Dentistry, Nacional Federico Villareal University, Lima, Peru. Universidad Nacional Federico Villarreal School of Dentistry Nacional Federico Villareal University Lima Peru
| | - María Jimena Ramírez-Mejía
- School of Dentistry, Peruana de Ciencias Aplicadas University, Lima, Peru. Universidad Peruana de Ciencias Aplicadas School of Dentistry Peruana de Ciencias Aplicadas University Lima Peru
| | - Ana Carolina Zorrilla-Mattos
- School of Dentistry, Privada Antenor Orrego University, Trujillo, Peru. Universidad Privada Antenor Orrego School of Dentistry Privada Antenor Orrego University Trujillo Peru
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Post-treatment Stability in Orthodontic Retention with Twistflex Retainers-Do Patients Benefit from Additional Removable Retainers? Clin Oral Investig 2022; 26:5215-5222. [PMID: 35474552 PMCID: PMC9381486 DOI: 10.1007/s00784-022-04490-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 04/12/2022] [Indexed: 11/14/2022]
Abstract
Objectives To evaluate post-treatment movements of lower anterior teeth during orthodontic retention in patients with fixed twistflex retainers versus those with combined fixed and removable retainers. Materials and Methods This study was based on a retrospective data analysis of 57 adult patients during orthodontic retention. They were assigned to two groups: In group 1 (n = 30) the lower jaw was provided with twistflex retainers only and in group 2 (n = 27) with a twistflex combined with a removable retainer for night-time use. Orthodontic study models of the lower jaw were digitalized and superimposed. Tooth movements were analyzed at the retainer bonding (t0) and follow-up appointment ≥ six months later (t1). Rotational tooth movements (°) were measured around the x-axis (mesial/distal direction), the y-axis (buccal/lingual direction) and the z-axis (longitudinal direction, tooth axis). Translational tooth movements (mm) were registered along the x-axis (buccal/lingual direction), the y-axis (mesial/distal direction) and the z-axis (apical/coronal direction). Results Canine and incisor position changes during orthodontic retention were more pronounced in group 1 compared to group 2 except for canine rotations around the z-axis. In both groups in most of the cases stable lower incisor alignment could be found, but the proportion was significant higher in group 2 (group 1: 56.7% vs. group 2: 81.5%). Severe misalignment was present in 13.3% of the participants of group 1 and only in 7.4% of group 2. The extent of canine tipping and movements along the x- and y-axis in severe misalignment cases was significantly lower in group 2 compared to 1. Conclusions Lower incisor alignment was more stable in patients with combined fixed and removable retainers compared to fixed retainers only. Clinical Relevance Based on the present findings, the routinely application of supplementary removable retainers can be recommended to enhance anterior tooth alignment in patients with fixed twistflex retainers.
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Bionic Anti-Slipping Crimping Structure for Industrial Hose Assembly Inspired by Ruminant Molars. Appl Bionics Biomech 2022; 2022:5632586. [PMID: 35392360 PMCID: PMC8983261 DOI: 10.1155/2022/5632586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/01/2022] [Accepted: 03/17/2022] [Indexed: 11/19/2022] Open
Abstract
It is highly desirable to improve the anti-slipping stability of the crimping structure for a reliable connection. This study innovatively presents a biomimetic strategy for designing a high-performance crimping structure for industrial hose assembly based on evidence that the special infundibulum dentis structure on the occlusal surface of ruminant molars has the potential of anti-slippage and can also reduce the risk of stress concentration. Utilizing reverse engineering technology, the three-dimensional (3D) digital model of the bovine molar was built as a representative prototype, and then corresponding characteristics of the infundibulum dentis were extracted with a fitting method for the bionic design of the crimping structure. Numerical simulations and experimental results both indicate that the bionic crimping structure has high resistance to slippage of hose body compared with the traditional type, and further, the formation mechanism of bionic anti-slipping performance was discussed.
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Charavet C, Vives F, Aroca S, Dridi SM. “Wire Syndrome” Following Bonded Orthodontic Retainers: A Systematic Review of the Literature. Healthcare (Basel) 2022; 10:healthcare10020379. [PMID: 35206992 PMCID: PMC8871980 DOI: 10.3390/healthcare10020379] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/09/2022] [Accepted: 02/15/2022] [Indexed: 01/27/2023] Open
Abstract
(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).
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Affiliation(s)
- Carole Charavet
- Université Côte d’Azur, Faculté de Chirurgie Dentaire, Département d’Orthodontie, 06000 Nice, France;
- Centre Hospitalier Universitaire (CHU) de Nice, Pôle Odontologie, UEC Orthodontie, 06000 Nice, France
- Laboratoire MICORALIS UPR 7354, Université Côte d’Azur, 06000 Nice, France;
- Correspondence: or
| | - France Vives
- Université Côte d’Azur, Faculté de Chirurgie Dentaire, Département d’Orthodontie, 06000 Nice, France;
- Centre Hospitalier Universitaire (CHU) de Nice, Pôle Odontologie, UEC Orthodontie, 06000 Nice, France
| | - Sofia Aroca
- Pratique Privée, 75116 Paris, France;
- University of Bern, Department of Periodontology, 3012 Bern, Switzerland
| | - Sophie-Myriam Dridi
- Laboratoire MICORALIS UPR 7354, Université Côte d’Azur, 06000 Nice, France;
- Université Côte d’Azur, Faculté de Chirurgie Dentaire, Département de Parodontologie, 06000 Nice, France
- Centre Hospitalier Universitaire (CHU) de Nice, Pôle Odontologie, UEC Parodontologie, 06000 Nice, France
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Three-dimensional imaging and molecular analysis of the effects of photobiomodulation and mechanical vibration on orthodontic retention treatment in rats : Effects of photobiomodulation and mechanical vibration on orthodontic retention treatment. J Orofac Orthop 2021; 83:24-41. [PMID: 34009424 DOI: 10.1007/s00056-021-00296-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 03/15/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE We aimed to evaluate and compare effects of photobiomodulation (PBM) and low-magnitude high-frequency mechanical vibration (HFMV) on orthodontic retention. METHODS Sixty-four female Wistar albino rats were divided into 9 groups (2 negative and positive controls each, 3 PBM and 2 HFMV groups) and studied for 25 days. In the experimental groups, closed nickel-titanium closed coil springs with a 50 cN force were placed for 10 days between the maxillary incisor and molar. PBM and HFMV were applied daily over long- (15 days) and short-term (7 days) retention periods. The PBM groups received PBM with a single wavelength (650 nm) or higher wavelengths (532, 650, 940 nm) for 9 min per day. HFMV groups received HFMV of 10, 20, and 30 Hz for 10 min per day. Right and left maxilla were assessed using micro-computed tomography imaging and real-time polymerase chain reaction. The amount of tooth movement during the retention period, expression levels of cyclooxygenase‑2 (COX-2), osteoprotegerin (OPG), and receptor activator of nuclear factor-kappa B ligand (RANKL) mRNA gene expression levels, OPG/RANKL ratios, alveolar bone trabecular thickness (Tb.Th), trabecular number (Tb.N), and structure model index were analyzed. Kruskal-Wallis and Mann-Whitney U tests were used for multiple comparisons of the nonparametric distributed data and binary comparisons, respectively. RESULTS When using the long-term retention protocol, PBM and HFMV treatment increased Tb.N (p < 0.05) and decreased COX‑2 mRNA gene expression levels (p < 0.05) and Tb.Th (p < 0.05) compared to controls. For short-term retention, PBM and HFMV decreased the amount of relapse tooth movement compared to controls. In addition, Tb.Th (p < 0.05) and the mRNA gene expression levels of COX‑2 and RANKL (p < 0.05) were decreased. CONCLUSION PBM and HFMV might be able to support retention after orthodontic tooth movement by reducing bone resorption and increasing bone quality.
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Knaup I, Bartz JR, Schulze-Späte U, Craveiro RB, Kirschneck C, Wolf M. Side effects of twistflex retainers-3D evaluation of tooth movement after retainer debonding. J Orofac Orthop 2020; 82:121-130. [PMID: 33258981 DOI: 10.1007/s00056-020-00265-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 08/16/2020] [Indexed: 10/22/2022]
Abstract
PURPOSE Evaluation of tooth movement after retainer debonding in retainer-associated misalignment cases. METHODS This pilot study is based on a retrospective data analysis. Adult patients (age 25.5 ± 4.9 years) wearing fixed twistflex retainers and having visible retainer-associated misalignment were included and examined for tooth movement after retainer debonding. Orthodontic study models were taken at retainer debonding (t0) and 14 (±1) weeks later (t1). They were digitally superimposed using 2D/3D dental imaging software and tooth movement was analyzed in all three dimensions. RESULTS A total of 23 teeth (12 upper teeth: 10 incisors, 2 canines; 11 lower teeth: 7 incisors, 4 canines) were analyzed. Mean overall tipping was 1.11 ± 0.82° in the mesial/distal direction (angulation, x‑axis), 2.02 ± 1.9° in the buccal/lingual direction (inclination, y‑axis) and 1.28 ± 0.99° around the tooth axis (z-axis). Mean overall bodily movement was 0.30 ± 0.31 mm in the mesial/distal direction (angulation, x‑axis), 0.10 ± 0.13 mm in the buccal/lingual direction (inclination, y‑axis), and mean in- or extrusion 0.22 ± 0.24 mm (z-axis). Mean tipping and bodily movement were more pronounced in the upper jaw. CONCLUSION The present data shows that tooth movement after debonding of twistflex retainers can be expected in misalignment cases.
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Affiliation(s)
- Isabel Knaup
- Department of Orthodontics, RWTH Aachen University Hospital, Aachen, Germany.
| | - Jenny Rosa Bartz
- Department of Orthodontics, RWTH Aachen University Hospital, Aachen, Germany
| | - Ulrike Schulze-Späte
- Section of Geriodontics, Department of Conservative Dentistry and Periodontology, Jena University Hospital, Jena, Germany
| | | | | | - Michael Wolf
- Department of Orthodontics, RWTH Aachen University Hospital, Aachen, Germany
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Klaus K, Xirouchaki F, Ruf S. 3D-analysis of unwanted tooth movements despite bonded orthodontic retainers: a pilot study. BMC Oral Health 2020; 20:308. [PMID: 33148238 PMCID: PMC7643263 DOI: 10.1186/s12903-020-01304-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/29/2020] [Indexed: 11/24/2022] Open
Abstract
Background Recently, reports of unwanted tooth movements despite intact orthodontic bonded retainers have increased. These movements are not subject to relapse but are classified as a new developed malocclusion. The aims of the present pilot study were to analyze the prevalence of unwanted tooth movements despite intact bonded cuspid-to-cuspid retainers and to identify possible predisposing factors.
Materials and methods Plaster casts of all patients finishing orthodontic treatment during three consecutive years were assessed before treatment (T0), after multibracket appliance debonding (T1) and after two years of retention (T2). After multibracket appliance treatment, all patients received a cuspid-to-cuspid flexible spiral wire retainer bonded to each tooth of the retained segment in the upper and lower jaw. The study group (SG) consisted of 44 patients (16 male, 28 female) with tooth movements (T1–T2) of the retained segment despite intact bonded cuspid-to-cuspid retainer and the control group (CG) of 43 patients (19 male, 24 female) without unwanted tooth movements. The casts of the SG were digitized, superimposed and measured. Using the Chi-square test, Fisher´s exact test and Mann–Whitney-U-test (p < 0.05), mandibular plane angle, incisor proclination, oral dysfunctions or habits (T0) and intercanine distance, overjet and interincisal relationship (T0, T1, T2) were compared between SG and CG. Results The prevalence of patients with unwanted tooth movements in one or both jaws was 27.0%. Maxillary retainers were affected more often (20.9%) than mandibular retainers (14.1%). The median amount of tooth movements was 0 to 0.66 mm with large interindividual variations. Oral dysfunctions or habits at T0, such as a lack of interincisal contact at all time points, were associated with unwanted tooth movements. Conclusion Unwanted tooth movements occurred more often with maxillary than mandibular retainers. Patients with oral dysfunctions/habits and without interincisal contact had a higher prevalence of unwanted tooth movements.
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Affiliation(s)
- Katharina Klaus
- Department of Orthodontics, Justus-Liebig-University Giessen, Schlangenzahl 14, 35392, Giessen, Germany.
| | - Faidra Xirouchaki
- Private Practice, Ethnomartiron 70A, 71409, Heraklion (Iraclio), Crete, Greece
| | - Sabine Ruf
- Department of Orthodontics, Justus-Liebig-University Giessen, Schlangenzahl 14, 35392, Giessen, Germany
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Analysing the potential of hydrophilic adhesive systems to optimise orthodontic bracket rebonding. Head Face Med 2020; 16:20. [PMID: 32891153 PMCID: PMC7487826 DOI: 10.1186/s13005-020-00233-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 09/01/2020] [Indexed: 11/24/2022] Open
Abstract
Introduction Bond failure during fixed orthodontic treatment is a frequently occurring problem. As bracket rebonding is associated with reduced shear bond strength, the aim of the present investigation is to analyse the effect of different innovative rebonding systems to identify optimised rebonding protocols for orthodontic patient care. Methods Metallic brackets were bonded to the frontal enamel surfaces of 240 bovine lower incisors embedded in resin bases. Teeth were randomly divided into two major experimental groups: in group 1 a hydrophilic primer (Assure™ PLUS) was compared to commonly used orthodontic adhesives (Transbond XT™, BrackFix®, Grengloo™) and a zero control. In group 2 different rebonding systems were analysed using a hydrophilic primer (Assure™ PLUS), a methyl methacrylate-consisting primer (Plastic Conditioner) and a conventional adhesive (Transbond XT™). All teeth were tested for shear bond strength according to the DIN-13990 standard, the Adhesive Remnant Index and enamel fracture rate. Results The hydrophilic primer enhanced shear bond strength at first bonding (Assure™ PLUS 20.29 ± 4.95 MPa vs. Transbond XT™ 18.45 ± 2.57 MPa; BrackFix® 17 ± 5.2 MPa; Grengloo™ 19.08 ± 3.19 MPa; Meron 8.7 ± 3.9 MPa) and second bonding (Assure™ PLUS 16.76 ± 3.71 MPa vs. Transbond XT™ 13.06 ± 3.19 MPa). Using Plastic Conditioner did not seem to improve shear bond strength at rebonding (13.57 ± 2.94). When enamel etching was left out, required shear bond strength could not be achieved (Plastic Conditioner + Assure™ PLUS 8.12 ± 3.34 MPa; Plastic Conditioner: 3.7 ± 1.95 MPa). Hydrophilic priming systems showed decreased ARI-scores (second bonding: 2.63) and increased enamel fracture rates (first bonding: 55%; second bonding 21,05%). Conclusions Based on the present study we found that rebonding strength could be compensated by the use of hydrophilic priming systems. The additional use of a methyl methacrylate-consisting primer does not seem to enhance shear bond strength. No etching approaches resulted in non-sufficient bond strength.
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Moda LB, da Silva Barros ALC, Fagundes NCF, Normando D, Maia LC, Mendes SMDA. Lower fixed retainers: bonded on all teeth or only on canines? A systematic review. Angle Orthod 2019; 90:125-143. [PMID: 31536378 DOI: 10.2319/013019-63.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVE To evaluate the stability after orthodontic treatment between two types of lower fixed retainers: those bonded onto all anterior teeth or those bonded only onto the canines. MATERIALS AND METHODS The following electronic databases were consulted: PubMed, Scopus, Web of Science, Cochrane Library, Lilacs, OpenGrey, ClinicalTrials, and Google Scholar. No restriction of language or year were applied. After selection of studies, risk-of-bias evaluation and qualitative synthesis of the included studies were performed using The Cochrane Collaboration's tool for randomized studies and the "Risk of Bias in Non-randomized Studies of Interventions" (ROBINS-I) tool for nonrandomized studies, and a summary of the overall strength of evidence was presented using the "Grading of recommendations, assessment, development and evaluation" tool. RESULTS Among the 180 studies retrieved from the searches, five were included in this review. Three of them showed a low risk of bias, while two presented a high risk of bias. With regard to stability, two studies reported better stability for retainers bonded to all six teeth, while the other three showed no difference. The retainer bonded to all teeth presented a higher breakage rate in one study. CONCLUSIONS Stability seems better with lower fixed retainers bonded on all anterior teeth. The breakage rate may not change according to the bonding. However, studies with greater methodological soundness are necessary to reach a more reliable conclusion.
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Möhlhenrich SC, Jäger F, Jäger A, Schumacher P, Wolf M, Fritz U, Bourauel C. Biomechanical properties of CAD/CAM-individualized nickel-titanium lingual retainers: an in vitro study. J Orofac Orthop 2018; 79:309-319. [PMID: 30014179 DOI: 10.1007/s00056-018-0144-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 06/11/2018] [Indexed: 11/25/2022]
Abstract
PURPOSE This study aimed to determine and compare the mechanical properties of novel CAD/CAM(computer-aided design/manufacturing)-individualized nickel-titanium (NiTi) and conventional twisted wires. METHODS Seven NiTi wires (angular, 0.20 × 0.20 mm up to 0.50 × 0.50 mm) and two twisted steel wires (round, 0.40 mm and 0.44 mm) were investigated in three-point (3PBT) and four-point bending tests (4PBT) using the Orthodontic Measurement and Simulation System. All wires were loaded up to a distance of 3.3 mm, and resulting forces were measured. Additionally, in the biomechanical test (BMT), CAD/CAM-individualized NiTi retainers (0.35 × 0.35 mm) were subjected to intrusive and extrusive deformation of 0.1, 0.2, and 0.4 mm. RESULTS For twisted wires, typical plastic deformations were found in 3PBT (0.40 mm: 0.3 mm; 0.44 mm: 0.4 mm), and maximum resulting forces for these reached 1.3 N and 3.2 N for the 0.40 mm and 0.44 mm wires, respectively. Corresponding values in the 4PBT totaled 0.8 N for the 0.40 mm and 1.9 N for the 0.44 mm twisted wire. The NiTi samples showed plastic deformations in the 3PBT for the 0.25 × 0.25 mm dimension and in 4PBT for the 0.35 mm × 0.35 mm version. At a deflection of 1.5 mm, both tests revealed significantly different forces for the NiTi wires of different dimensions (p ≤ 0.001). In the BMT, no remarkable loading plateau or plastic deformation was observed. The resulting forces were significantly higher for extrusive than for intrusive deformation (p ≤ 0.001). CONCLUSIONS Individualized NiTi retainers feature specific elasticity and dimensional stability, and more deflection is necessary to achieve permanent deformations. The CAD/CAM production process did not significantly influence the biomechanical properties of the NiTi wires.
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Affiliation(s)
- Stephan Christian Möhlhenrich
- Department of Orthodontics and Dentofacial Orthopedics, University Hospital of the RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
| | - Fabian Jäger
- Department of Orthodontics and Dentofacial Orthopedics, University Hospital of the RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Andreas Jäger
- Department of Orthodontics and Dentofacial Orthopedics, University of Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
| | | | - Michael Wolf
- Department of Orthodontics and Dentofacial Orthopedics, University Hospital of the RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Ulrike Fritz
- Department of Orthodontics and Dentofacial Orthopedics, University Hospital of the RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Christoph Bourauel
- Department of Oral Technology, University of Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
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