Retention Appliance Research Articles

The Common Retention Practices Among Orthodontists from Different Countries.

To investigate the most common retention practices, factors influencing the retention protocol, and the differences among orthodontists regarding retention practices. An online validated questionnaire was anonymously sent to 3,000 orthodontic residents and clinicians. The survey consisted of 19 questions regarding the participants' demographics, prescribed retention appliances, factors affecting retention appliance choices, and adjunctive retention procedures. Descriptive statistics, Chi2 and Kendall's Tau-b tests were applied. Five hundred fifty-five orthodontic residents and clinicians, 53.3% males and 46.7% females, completed the survey, indicating a response rate of 18.5%. Although participants' demographics, type of treatment and pre-treatment malocclusion influence the choice of retention protocols, thermoplastic retainers (TR) were the most popular retention regime for the maxillary arch for both adults (47.4%) and adolescents (42.3%). Bonded retainers (BR) were the favored option for the mandibular arch (44.9% of adults and 40.7% of adolescents). The degree of arch expansion (64.1%) and the degree of interdigitation (50.1%) after treatment were the most influential factors for the choice of the preferred type of retainers by the respondents. 68.6% of the participants thought professional retention guidelines would be useful. Thermoplastic retainers were the most common retention appliances for adults and adolescents in the maxilla. At the same time, BR was the most favored retainer in the mandibular arch, with clinical experience, practice setting, and malocclusion- and treatment-related factors influencing the type of the chosen appliance. The demographic differences and the uneven participation in the survey need to be considered while interpreting the findings of this study.

“Comparing the effectiveness, acceptability and oral hygiene status between vacuum formed retainer and Begg’s retainer”: a pilot study

BackgroundRecently, Vacuum formed retainers (VFRs) are preferred as an Orthodontic retention appliance over conventional Begg’s retainers. Very few studies have been conducted between VFRs and Begg’s retainers. Hence, this study aims at assessing the effectiveness, oral hygiene and acceptability between VFRs and Begg’s retainers with a follow up period of 1 year.MethodsEighty patients who completed fixed Orthodontic treatment were included. Retainers were delivered on the same day of debonding. Retainer 1/ R1 stands for VFRs and Retainer 2/ R2 stands for Begg’s retainers. The retainers were randomly allocated to both the arches. 40 VFRs and Begg’s retainers in maxillary and mandibular arch were given respectively.Effectiveness, oral hygiene condition were performed at T0 (After debonding), T1 (3 months after using retainers), T2 (6 months after using retainers), T3 (9 months after using retainers), T4 (12 months after using retainers) follow up stages, except the feedback form and the breakage of retainers that were filled at T4 stage.ResultsBoth R1 and R2 retainers showed improvement in teeth alignment in both the arches at follow up stages. Interproximal contacts in maxillary and mandibular arch with VFRs and Begg’s retainers improved to 77.5% and 82.5% respectively. Considering the marginal ridge, Begg’s retainers and VFRs showed 95%, 55% increased proportion at T4 respectively (p < 0.05). Patients wearing Beggs’s retainers had significantly better (p < 0.05) oral hygiene status.Significant differences were observed with Begg’s retainers in teeth biting, whereas no significant difference was found with fitting of appliance (p = 0.180) and gingival irritation (p = 1.000). VFRs were well accepted aesthetically that was significant. Retainers were prone to breakage but was not significant (p = 0.162).ConclusionBegg’s wrap around retainers maintain good oral hygiene, improve the teeth alignment, interproximal contact and marginal ridges post Orthodontic treatment with better fitting of the appliance. VFRs are also preferred as they are good in maintaining proper teeth alignment with progressive improvement in the interproximal contacts and are aesthetically pleasing.

Knowledge, attitude, and awareness on the protocols and trends in orthodontic retention among dental students.

This survey aimed at evaluating the knowledge and awareness regarding the various retention protocols used in orthodontic practice. A survey has been conducted among the dental students by circulating 15 close-ended questions online to analyze the data collected on the protocols and trends in orthodontic retention. The male and female distribution among the study population was evaluated, and the retention protocols used were computed; statistical analysis was performed using SPSS software. Ninety-four percent accepted that Hawley retainers are predominantly used compared to fixed retainers. Eighty-seven percent agreed that they aim at a more stable dentition by the completion of orthodontic treatment. The Chi-square test on the knowledge of respondents on the permanent retention to be followed after orthodontic treatment to close generalized spacing is statistically not significant, P = 0.056. Within the considered limitations, it is clear that there is awareness among the dentists regarding the use of a retention appliance to ensure stability at the finish of orthodontic treatment. But the protocol for the same remains variable. Further studies can be performed to identify the effectiveness of each of the different retention protocols and their indications in various cases.

Retention in Orthodontics: A review

Skeletal and dental correction obtained by orthodontic treatment may tend to return to the pre-treatment state. This condition is defined as relapse. The retention phase applied after treatment is important to obtain stable results. Periodontium, soft tissue pressures, growth and occlusion are among the factors affecting stability. In the last decade, interest in retention procedures has increased and it has been found that retention regimes differ from country to country. Although retention affects nearly every patient, there is minimal agreement on the most appropriate approach to be taken in an individual case. The many variations of the retention procedure, the introduction of different materials for retention, or individual patient factors are among the reasons that lead to difficulties in selecting retention protocols. Basic retention protocol is provided with removable and fixed retention appliances. For removable retention, hawley, wraparound, vacuum formed retention appliance and positioners are used. For fixed retention, rigid steel retention wire bonded to terminal teeth or flexible retention wires bonded to all teeth between 3-3 can be preferred. NiTi retention wires produced with CAD / CAM technology are also among the current materials. While fixed retention appliances do not require patient cooperation, periodontal follow-up is recommended. Patient cooperation is needed for the use of removable retention appliances, but easy cleaning of removable appliances is an advantage. ‘Adjunct’ procedures may also be applied to the teeth or surrounding periodontium to assist the retention process. For example, it involves reshaping teeth such as interproximal reduction or circumferential supracrestal fiberotomy. In this review, information about retention is discussed in the light of current literature. How to cite this article: Seki Yurdakul M, Meriç P. Retention in Orthodontics: A review. Int Dent Res 2022;12(2):88-96. https://doi.org/10.5577/intdentres.2022.vol12.no2.7 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Retention protocol following post-orthodontic treatment in cleft palate patients – A review

To evaluate and compare the available literature on efficiency of different retention appliances in maintaining the results achieved after orthodontic treatment in cleft palate patients. On comparing the literature available on different retention appliances currently available, it was found that the cast metal retainers offered a more stable and rigid design to maintain the post treatment arch width and also provided the aesthetic replacement of the missing teeth in the cleft region by incorporating a pontic. The cleft lip and palate patients should be informed and motivated for a long term or indefinite retention phase irrespective of the type of retention appliance used. Presently, very few studies are available comparing the effectiveness of different retention protocols in cleft lip and palate patients. Hence, there is need to conduct evidence based high quality longitudinal studies to compare the effectiveness of different retention appliances.

Difference in Orthodontic Patients’ Perceptions of Essix and Hawley Retainers

Objective: To determine differences in how orthodontic patients perceive the aesthetics relating to the use of Essix and Hawley retainers. Material and Methods: Photographs of a female patient using an Essix retainer and a Hawley retainer, respectively, were assessed by 70 orthodontic patients aged between 21 and 55 years. All participants were provided with the same images of the two retainer types being worn and were asked to grade the aesthetics of each retainer using a visual analog scale . The significance of differences in orthodontic patient perceptions of aesthetics in the use of Essix and Hawley Retainers in the young adult and adult age groups were tested using the Mann-Whitney test with assumed significance p<0.01. Results: There were differences in participants’ perceptions between the two retainers that were statistically significant, with responses varying between young adults aged 21 to 35 years and adults aged 36 to 55 years. According to the VAS, the two retainers’ average scores in the total population are 82 for Essix Retainer and 60 for Hawley Retainer in both groups . Conclusion: The Essix retainer as a retention appliance is considered more aesthetically pleasing than the Hawley retainer among both young and middle-aged adults.

Comparison of post-treatment changes with and without retention in adolescents treated for maxillary impacted canines—a randomized controlled trial

SummaryObjectiveTo evaluate whether retention is needed after orthodontic treatment of impacted maxillary canines.Trial designTwo-arm parallel group single-centre randomized controlled trial.Materials and methodsSixty-three patients, 39 girls and 24 boys, were recruited to the study. The inclusion criteria were patients with at least one impacted or unerupted maxillary canine, and moderate irregularity of the maxillary six anterior teeth according to Little’s index (LI). After gaining informed consent from the patient and their custodians, the patients were randomized to one of two groups, i.e. to a non-retention group or a retention group. The randomization process was prepared and carried out by an independent person not involved in the trial and the randomization used blocks of 20 (10 + 10). Primary outcomes were changes in single contact point discrepancy, and LI measured on digitalized three-dimensional study casts 1-year post-treatment. The study casts were anonymized before assessment and the changes were blinded for the assessor. Data were evaluated on an intention-to-treat basis. Thus, all randomized patients were incorporated into the final analysis. In the non-retention group a 10-week interim period was used to detect patients who eventually have a relapse immediately after treatment. If so, the patient got the arch-wire reinserted. Most patients in the retention group received a vacuum-formed retainer and pretreatment spacing cases got a bonded retainer.ResultsMean irregularity change was 0.4 mm in the retention and 1.3 mm in the non-retention group (P < 0.001). Maximum change was 2.5 mm in the retention and 3.2 mm in the non-retention group (P < 0.001). Most changes in the non-retention group occurred during the 10-week interim period. In the non-retention group, one patient developed contact point discrepancy of >2 mm during the interim period and was realigned.HarmsOne patient met the stopping guideline criteria. This patient had the arch wire reinserted for 2 months. After realignment, the patient received a retention appliance.LimitationsThe trial was a single-centre study and short-term changes were evaluated.ConclusionsChanges between the retention and the non-retention group were statistically but not clinically significant. Since satisfactory clinical results 1-year post-treatment were found in the non-retention group, retention does not appear to be needed. The 10-week interim period was useful in detecting patients who might have a relapse immediately after treatment.Trial registrationThe trial was not registered.

Orthodontist Clinical Experience and Clinical Situation Significantly Influence the Retention Protocol – a Survey from Croatia

SUMMARYThe aim was to assess the views and practice of Croatian orthodontists concerning retention protocols. A total of 150 questionnaire copies were distributed, of which 92 were validly completed. The survey included sociodemographic characteristics, practices of informing patients about retention options, commonly used appliances, and reasons for choosing a particular type of retention and treatment duration. Orthodontists informed patients about retention mostly verbally, the retention period was 3-5 years, the choice of method depended on the malocclusion (76%), and the protocol was influenced by clinical experience of the orthodontist (39%). The most commonly used appliance in the maxilla was the vacuum-formed retainer (52%), whereas a combination of fixed and removable retainers was most common in the mandible (34%). Modus of acquiring knowledge, biological reasons (malocclusion type, oral health, treatment outcome, and growth) and the patient’s wishes were not a predictor of retention duration or recall frequency. With an increase in orthodontic experience, the duration of retention decreased and orthodontists were more likely to change the duration of retention (p=0.001), as well as the type of retention appliance (p<0.001). In conclusion, retention protocols among Croatian orthodontists were influenced mostly by their clinical experience and clinical situation.

Esthetic Simultaneous Intrusion and Retention (E-SIR) Appliance

Esthetic Simultaneous Intrusion and Retention (E-SIR) Appliance

Stability of orthodontic treatment outcome in relation to retention status: An 8-year follow-up.

Our aim was to evaluate the stability of orthodontic treatment outcome and retention status 7 or more years after active treatment in relation to posttreatment or postretention time, type of retention appliance, and duration of retainer use. The subjects were former patients who completed orthodontic treatment with fixed appliances from 2000 to 2007. The pretreatment eligibility criteria were anterior crowding of 4mm or more in the maxilla or the mandible and Angle Class I or Class II sagittal molar relationship. Acceptable pretreatment and posttreatment dental casts were required. A total of 67 patients participated, 24 men and 43 women, with a mean age of 24.7years (range, 20.0-50.0years). All participants had a follow-up clinical examination, which included impressions for follow-up casts, and each completed a questionnaire. Data were obtained from pretreatment, posttreatment, and follow-up (T2) casts as well as from the patients' dental records. Treatment stability was evaluated with the peer assessment rating (PAR) index and Little's irregularity index. The participation rate was 64%. The average posttreatment time was 8.5years (range, 7.0-11.0). All participants had received a retainer in the mandible, maxilla, or both after active treatment. At T2, the PAR score showed a mean relapse of 14%. The majority (78%) of participants still had a fixed retainer at T2 (retainer group), and 22% had been out of retention for at least 1year (postretention group). The relapse according to the PAR did not differ significantly between participants with and without a retainer at T2. From posttreatment to T2, the irregularity of the mandibular incisors increased almost 3 times more in participants with no retainer in the mandible compared with those with an intact retainer at T2 (P=0.001). In the maxilla, no corresponding difference was found. Our results suggest that occlusal relapse can be expected after active orthodontic treatment irrespective of long-term use of fixed retainers. Fixed canine-to-canine retainers seem effective to maintain mandibular incisor alignment, whereas in the maxilla a fixed retainer may not make any difference in the long term.

Tricks of the trade: fixed retention appliance (FRA): an effective retention appliance with a simple design

Orthodontic UpdateVol. 9, No. 3 ArticlesTricks of the trade: fixed retention appliance (FRA): an effective retention appliance with a simple designReji Abraham, Geetha Kamath, Harsimrat Kaur, Favaz ShajReji AbrahamSearch for more papers by this author, Geetha KamathSearch for more papers by this author, Harsimrat KaurSearch for more papers by this author, Favaz ShajSearch for more papers by this authorReji Abraham; Geetha Kamath; Harsimrat Kaur; Favaz ShajPublished Online:18 Jul 2017https://doi.org/10.12968/ortu.2016.9.3.112AboutSectionsView articleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail View article

Comparison of the effects of different retention appliances on the oxidant–antioxidant system

The aim was to compare oxidative stress (OS) levels with different types of retention appliance. Thirty orthodontic patients were divided into three groups: Group 1 (Essix retainer), Group 2 (lingual retainer with stainless steel retainer wire), and Group 3 (lingual retainer with fiber-reinforced material). OS was assessed in the subjects’ saliva. Saliva samples were taken from the patients at T0 (before using the retention appliance), T1 (first month of retention), and T2 (third month of retention). The specimens were investigated to detect changes in total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI). TAS values in Group 2 were significantly higher than in Group 3. TOS values in Group 3 were significantly lower than in the other groups. TOS values in Group 2 were lower than in Group 1. OSI values of Group 1 were higher than those in Group 2 or 3. There was no statistically significant difference among the time periods. The type of retention appliance affected OS values. A fiber-reinforced material may have a lower OSI. OS or products can affect some systemic disease; therefore, the selection of the retainer will be important on these patients.

Orthodontic occlusion and temporary removable retainers

Implementing retention at end of orthodontic treatment is not straightforward: it may induce harmful side-effects on occlusion, muscles, joints and posture.To foresee and prevent such risks, exhaustive clinical examination should be performed ahead of the retention phase: history taking, intra- and extra-oral examination, and static and dynamic analysis. The choice of type of retention appliance will result from this appraisal:The practitioner should be rigorous in producing the device (form and choice of material), fitting it (fixity, stabilization), adjusting it (balance), and above all in follow-up.Whatever the selected retention system, regular clinical follow-up is mandatory, to monitor ongoing adaptive balance: teeth, joints, muscles, etc.

A cost-minimization analysis of an RCT of three retention methods

There are few cost evaluation studies of orthodontic retention treatment. The aim of this study was to compare the costs in a randomized controlled trial of three retention methods during 2 years of retention treatment. To determine which alternative has the lower cost, a cost-minimization analysis (CMA) was undertaken, based on that the outcome of the treatment alternatives was equivalent. The study comprised 75 patients in 3 groups consisting of 25 each. The first group had a vacuum-formed retainer (VFR) in the maxilla and a cuspid retainer in the mandible (group V-CTC), the second group had a VFR in the maxilla combined with stripping of the incisors and cuspids in the mandible (group V-S), and the third group had a prefabricated positioner (group P). Direct cost (premises, staff salaries, material and laboratory costs) and indirect costs (loss of time at school) were calculated. Societal costs were defined as the sum of direct and indirect costs. The societal costs/patient for scheduled appointments for 2 years of retention treatment in group V-CTC were €497, group V-S €451 and group P €420. Societal costs for unscheduled appointments in group V-CTC were €807 and in group V-S €303. In group P, there were no unscheduled appointments. After 2 years of retention in compliant patients, the cuspid retainer was the least cost-effective retention appliance. The CMA showed that for a clinically similar result, there were differences in societal costs, but treatment decisions should always be performed on an individual basis.

A new type of modified Essix Retainer for anterior open bite retention

The most problematic malocclusion type to retain is anterior open bite although many classical retention appliances are known. The difficulty of maintaining the occlusion arises from the lack of control over the tongue behavior and posture in open bite cases. In the current article, a 2 year follow-up of 2 open-bite patients who were retained with a new type of retention appliance, successfully, were presented.

Simultaneous 3-Dimensional Le Fort I/Distraction Osteogenesis Technique: Positional Changes

This preliminary study assesses the positional changes of the maxilla after simultaneous 3-dimensional Le Fort I osteotomy and distraction osteogenesis (3D-LFI/DO). The records of 18 patients, 17.7 years of age (range, 12-38 years) at the time of surgery, manifesting transverse maxillary deficiencies and variable sagittal/vertical deformities were evaluated presurgically and 3 years postsurgery (range, 1 to 10 years). All patients underwent midsagittal 2-piece Le Fort I osteotomies. The planned sagittal and vertical positional changes were immediately performed by the Le Fort I surgery. After a latency period of 5 to 7 days, maxillary expansion was slowly achieved by distraction osteogenesis using a Hyrax appliance activated 1-mm/day. Once the planned transverse expansion had been attained, the Hyrax device served as a retention appliance for 8 to 12 weeks, after which the distraction gap was orthodontically closed. The morphological changes were assessed by comparing standardized preoperative and postsurgical models, posterior-anterior radiographs, and lateral cephalograms. Class I canine and molar relationships, along with satisfactory sagittal and vertical skeletal relationships, were observed at follow-up. The maxilla was advanced (1.5-1.8 mm) and positioned either superiorly or inferiorly (1.2-2.9 mm), depending on the original deformity. The arch perimeter increased 5.4 mm and the arch width increased between 4.2 and 6.6 mm. The maxillary expansion was nonparallel, greater anteriorly and inferiorly. The 3D-LFI/DO can be used to simultaneously and selectively widen, lengthen and vertically reposition the maxilla, producing acceptable post-treatment skeletal and dental relationships, without healing problems observed clinically.

An electromyographic evaluation of bilateral symmetry of masticatory, neck and trunk muscles activity in patients wearing a positioner

This study was designed to investigate the attitude of a positioner (Finition) or an Hawley's retention appliance to create a symmetric function of the masticatory, neck and trunk muscles during the orthodontic retention phase. Sixteen patients (18.5 +/- 2.2 years) were included in the sample. All the patients received an orthodontic therapy for the treatment of an Angle's class I malocclusion and skeletal class I, for a period of 2 years. After removal of orthodontic brackets, eight patients wore a teeth positioner (group I) as retention appliance and eight subjects wore an Hawley's appliance as upper retention (group II). Surface electromyographic (sEMG) activity was recorded from the bilateral anterior temporal, posterior temporal, masseter, sternocleidomastoid (SCM), upper and lower trapezius and cervical muscles at mandibular rest position and during maximal voluntary clenching (MVC) at T0, i.e. soon after the removal of orthodontic brackets and at T1, i.e. after 3 months of retention treatment. No significant difference was observed between the two groups at T0. At T1, at mandibular rest position, the group I showed a significantly lower sEMG activity of anterior temporal and SCM muscles compared with the group II. During MVC, at T1, the group I showed a significantly lower sEMG activity of the SCM and posterior cervicals, compared with the group II. The positioner seems to show a relevant effect on the sEMG activity of masticatory, neck and trunk muscles.

Stability of upper incisor inclination changes in Class II division 2 patients

The aim of this study was to evaluate the changes in incisor inclination following orthodontic treatment in Class II division 2 patients, and to assess the long-term stability after retention. Dental casts and cephalograms of 61 Class II division 2 patients (31 males and 30 females, mean age 13.4 years) with a closed lip seal were available before (T1), at the end of treatment (T2), and 3.5 years (mean) post-treatment (T3). A method of measuring upper incisor inclination on dental casts was developed for the purpose of the investigation. This involved placing markers on the study casts and then taking radiographs which were measured to establish the upper incisor inclination. Statistical analysis of the data included the calculation of mean values, standard deviation, standard errors, and ranges for each variable. Spearman ranked correlation coefficients were computed for selected model variables and scattergrams plotted. To investigate the influence of the chosen retention therapy, a Mann-Whitney U-test was used. The mean change in incisor inclination during orthodontic treatment was 15.2 degrees. There was a mean relapse of 2.2 degrees between T2 and T3, but this was not considered clinically relevant. The amount of relapse was independent of the type of the retention appliance (Hawley type retainer or lingual retainer). The relationship between long-term stability of the incisor inclination and between the lip line relative to the upper incisors was also investigated, based on cephalometric data. A mean decrease in lip line height of 0.6 mm was seen at T2 and, although the observed change was statistically significant, it would not be clinically relevant.

An Application of a Splint Purposeful Resin-Bonded Fixed Partial Denture after Orthodontic Treatment: A Case Report

An adult male patient who had lost his maxillary left central incisor seven years ago in a traffic accident presented with a chief complaint about his unaesthetic appearance associated with the loss of his maxillary left central incisor space, a Class III molar occlusion, and an anterior open bite malocclusion due to tongue-thrust swallowing. Fixed orthodontic treatment was rendered following fan-type expansion of the maxilla. A Maryland bridge as a minimally invasive dentistry approach was used as a retention appliance and the patient's aesthetic appearance was restored.

Floating norms and post-treatment overbite in open bite patients.

In this study, the clinical significance of three floating norm systems, the Bergen Box (BB), the Segner-Hasund Harmonybox 1 and 2 (SHH1 and SHH2), as well as the influence of treatment modalities for predicting results of an open bite treatment were investigated. In the BB and SHH1, patients with a steep mandibular plane angle or a skeletal open bite configuration (O1mand, O1mandmax, O1max, or N1mand) were considered 'high risk', while in the SHH2, only the configurations O1mand and O1mandmax were considered high risk. All other configurations were designated 'low risk'. It was postulated that in high risk patients, the overbite was likely to relapse into an open bite after retention. Cephalograms of 83 open bite patients taken before treatment (T1) and at the end of retention (T2) were studied. Patients designated as low risk generally had a normal overbite at T2 after treatment, regardless of which box was used. The risk configurations of the SHH1 and SHH2 at T1 were significant predictors of the overbite at T2, the first being slightly better compared with the SHH2. The main clinical values of the SHH1 and SHH2 are strongly supported by the relatively good success rate in distinguishing a low-risk configuration. Reliable prediction of the treatment results of high-risk patients with risk configurations according to the SHH is improved by evaluating treatment modalities. The posterior bite splint seemed to have a bite opening effect, while a bite closing effect was associated with the use of a removable retention appliance.