Three-dimensional microanalysis of tooth movement during the first 6 months of orthodontic double retention.

INTRODUCTION: This study performed a 3-dimensional analysis of tooth movement during orthodontic retention to assess the effectiveness of double retention (fixed and removable) in preventing undesired tooth movement. METHODS: One hundred randomly selected patients were included at the initiation of double orthodontic retention with fixed retainers and vacuum-formed splints (recommended to be worn 22 h/d) in both arches. Intraoral scans were performed directly (T0), 1 month (n = 88), 3 months (T2) (n = 78), and 6 months (T3) (n = 66) after retainer bonding. Nine reference points were marked on each tooth in every patient. Subsequent scans were superimposed, and point displacement was calculated. Statistical analysis was performed using the R statistical software (version 4.2.2; R Core Team, Vienna, Austria). RESULTS: Sample size calculation determined at least 55 patients were needed. The total dropout between T0 and T3 was 34 patients (did not show up for appointment). The median absolute displacement value of a single point between T0 and T3 was 0.015 mm. The most stable teeth were mandibular central incisors, whereas the least stable were mandibular molars. Most tooth displacements occurred between T0 and T2, then slowed down significantly. CONCLUSIONS: Double orthodontic retention prevents major tooth displacements in most patients during the first 6 months of retention; however, larger, unpredictable single-tooth displacement may occur in individual patients.

Patients' perception of orthodontic retainers: a systematic review.

BACKGROUND: Orthodontic retainers are widely used to prevent relapses after orthodontic treatment; however, evidence about patients' perceptions of retainers is lacking. OBJECTIVE: To assess patients' perception of orthodontic retainers. SEARCH METHODS: PubMed, Web of Science, Scopus, LILACS, LIVIVO, Cochrane Library, and gray literature (Google Scholar) were searched without date or language restrictions. A manual search of the reference lists of the included articles was also performed. SELECTION CRITERIA: Studies comparing patients' perceptions of wearing orthodontic retainers were included. DATA COLLECTION AND ANALYSIS: According to the study design, the risk of bias (RoB) assessment was performed using RoB 2.0 or ROBINS-I. The level of evidence was assessed through the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) tool. RESULTS: Seventeen studies met the eligibility criteria. After the RoB assessment, 12 randomized controlled trials presented a high RoB, and 4 non-randomized controlled trials presented a moderate RoB. The certainty of evidence was classified as very low for the four assessed outcomes. The studies generally reported an initial temporary negative impact of orthodontic retainers. Different esthetic, functional, and ease-of-use advantages are reported using removable and fixed retainers. A quantitative analysis was not performed due to the considerable clinical and methodological heterogeneity among the studies. CONCLUSION: The current evidence, although very limited, suggests that orthodontic retainers have an initial negative impact related to discomfort and functional limitations, but they seem to regress over time. There is a preference for thermoplastic over Hawley-type retainers. However, thermoplastic retainers cause different functional difficulties, and bonded retainers present the advantage of affecting speech function less than orthodontic removable retainers, although they can facilitate oral hygiene problems. REGISTRATION: PROSPERO (CRD42022306665).

[Evaluation of the effect of 3D printing resin splint based on the retention effect of orthodontic treatment in patients with periodontal disease].

PURPOSE: To investigate the difference in the retention effect of 3D printing resin splint and Hawley retainer combined with lingual retention wire in periodontal disease patients after orthodontic treatment. METHODS: Forty patients who finished orthodontic treatment for periodontal disease from January 2021 to February 2022 were selected and divided into experimental group and control group according to the random number table method, with 20 patients in each group. Patients in the experimental group used 3D printing resin splint for retention, while patients in the control group used Hawley retainer combined with a lingual retention wire for retention. The chair-side operation time of the retainers was recorded for both groups. The maxillary and mandibular cuspid width, molar width, overjet, overbite and irregularity index were measured at 1 month and 6 months after orthodontic treatment in both groups. Statistical analysis was performed with SPSS 12.0 software package. RESULTS: The mean time for chair-side manipulation of experimental group and control group was 8.23, 11.17 min, respectively. The difference between the two groups was statistically significant (P＜0.05) when comparing the width of the maxillary and mandibular cusps, the width of the molars, overjet, overbite and the irregularity index after 1 month and 6 months of wear of the retainers, which were significantly greater in the experimental group than in the control group at 6 months(P＜0.05). CONCLUSIONS: 3D printing resin splint, with short chair-side manipulation time, was more effective than Hawley retainer combined with a lingual retention wire, and the efficacy of both groups was otherwise generally consistent.

The dark side of fixed retainers: Case series.

This article focuses on on the presentation and management 9 adult patients who experienced complications because of their maxillary or mandibular fixed retainers 5-33 years after orthodontic treatment. Such complications include the development of an anterior crossbite, open bite, incisal cant, and twist- and x-effects. The detrimental effects on periodontal health were highlighted, especially in the mandibular canines. A range of fixed retainer types was identified, including flexible spiral wire bonded to 4 maxillary or 6 mandibular anterior teeth, rigid wire bonded to mandibular canines only and fiber-reinforced composite fixed retainer. Orthodontic retreatment was necessary in all patients using fixed appliances or clear aligners. Radiographic findings from cone-beam computed tomography or orthopantomogram before and after retreatment are presented when available. Despite the improvement of teeth position clinically, the cone-beam computed tomography scans taken directly after the completion of orthodontic retreatment did not show notable improvement with regards to root proximity to the cortical plates. The prevention of further complications was highlighted, including the use of dual retention, remote monitoring, frequent follow-up appointments and the importance of developing clear guidelines for monitoring patients in retention for treating clinicians and general dentists to promote early detection of adverse changes.

Tooth loss as a result of a bonded retainer: a case report.

To reduce the risk of unwanted post-treatment changes following orthodontic treatment, use of bonded retainers is gaining popularity. Despite their efficacy and popularity with patients, it has been widely reported that there are significant risks with bonded retainers if they are not maintained and monitored. This case report demonstrates how unwanted tooth movement caused by a bonded retainer can lead to catastrophic failure and ultimately, tooth loss. The importance of active and regular monitoring of bonded retainers is highlighted and recommendations are made to the wider dental community on how to monitor such retainers in clinical practice.

Comparison of multistranded wire and fiber-reinforced composite retainers effects on periodontium: A randomized clinical trial.

INTRODUCTION: Fixed orthodontic retainers are very important for treatment stability; however, adverse effects on the health of periodontium can be caused as a result of deposition of plaque and calculus. OBJECTIVES: To compare and determine the effects of two mandibular fixed lingual retainers on the periodontal status, and to test the null hypothesis that there would be no significant difference on the periodontium health between the patients using fiber-reinforced composite (FRC) or multistranded wire (MSW) fixed retainers. METHODS: A total of 60 subjects were recruited, out of which 6 were excluded and 2 dropped out during the study. Hence, 52 subjects with mean age of 21.5 ± 3.6 years were included in the study. The sample was composed by 8 males (15.4%) and 44 females (84.6%). The participants were randomly divided into two groups: Group 1 received fiber-reinforced composite retainer, while Group 2 received multistranded wire retainer. After insertion, plaque index, calculus index, gingival index and bleeding on probing were compared, after three months (T1), six months (T2), nine months (T3) and twelve months (T4), using Mann-Whitney test with p-value ≤ 0.05 as significant. RESULTS: It could be seen that the health of periodontium deteriorated with the passage of time from T1 to T4 in both group of retainers. However, no statistically significant differences were found between the two groups (p> 0.05). CONCLUSION: The results of the study indicate that there was no significant difference on the health of periodontium between the patients with FRC and MSW fixed retainers, hence, the null hypothesis was accepted.

Failure frequency of fixed mandibular retainers after pre-treatment of the enamel surface with pumice versus sandblasting-a randomized controlled trial.

BACKGROUND/OBJECTIVES: To compare retainer survival, periodontal health, and caries implications of fixed lower retainers bonded after pre-treatment of the enamel surface with either pumice or sandblasting. TRIAL DESIGN: Two-arm parallel-group, two-center randomized controlled clinical trial. METHODS: One hundred sixty patients (101 females, 59 males, mean age: 17.9) requiring mandibular retainers were consecutively recruited. Patients were randomly allocated to have pre-treatment of the enamel surface with either pumice (n = 80) or sandblasting (n = 80). The primary outcome was retainer survival at 3 (T1) and 12 months (T2) control. Secondary outcomes were carious lesions and periodontal health: plaque index (PI), gingival index (GI), calculus index (CI), and probing depth (PD). The randomization sequence was generated using an online randomization and allocation concealment was secured by contacting the sequence generator for treatment assignment. Blinding was not possible at T0 due to the nature of the intervention. Statistical analyses were carried out using the t-test, Fisher's exact test, repeated measure analysis of variance, and log rank test. RESULTS: Overall, the risk of bonding failure at T1 was 6.7 per cent and at T2 6.9 per cent. There were no statistically significant differences in failure rate between the two groups, neither at T1 (P = 1.000) nor at T2 (P = 0.360). No statistically significant differences were found for the intercanine periodontal indices GI, PI, CI, PD, and caries between the two groups at T0 and T1. At T2, significantly more gingivitis and plaque were seen in the sandblasting group (P = 0.05 and P = 0.047, respectively) compared with the pumice group. Calculus increased during the follow-up period in both groups (P ≤ 0.001) as well as plaque levels (P ≤ 0.001 and P = 0.025, respectively). No harm was reported. CONCLUSIONS: Enamel sandblasting prior to bonding mandibular retainers is not better at preventing bonding failure. REGISTRATION: 275767 (https://www.researchweb.org/is/sverige).

Patient perceptions and attitudes regarding post-orthodontic treatment changes.

OBJECTIVES: To determine patient perceptions and attitudes regarding posttreatment changes at least 2 years after completion of orthodontic treatment. MATERIALS AND METHODS: A total of 125 patients (75 females, 50 males, aged 22.93 ± 2.98 years) were enrolled at least 2 years after debonding. Participants had either vacuum-formed retainers (VFRs) or bonded retainers (BRs). Posttreatment changes were evaluated digitally by comparing tooth positions at debonding and at least 2 years after debonding. A questionnaire was used to assess patient attitudes. Retainer usage, awareness of relapse, satisfaction with their current occlusion, and whether posttreatment changes were severe enough for them to consider retreatment were investigated. RESULTS: All patients showed some posttreatment changes in irregularity. Only 74% of patients wearing VFRs and 47.1% of patients wearing BRs were aware of posttreatment changes. Patients were more likely to notice posttreatment changes if there was an increase in mandibular irregularity of 1-3 mm. Awareness of posttreatment changes in the upper arch was higher in both groups. The majority of participants were satisfied with the results even if they noticed some minor posttreatment changes (VFR, 69.4%; BR, 76.5%). Dissatisfaction with posttreatment changes did not necessarily mean that a patient wanted retreatment. CONCLUSIONS: A total of 26% of patients wearing VFRs and 52.9% of patients wearing BRs were unaware of posttreatment changes. Approximately half of the patients who noticed posttreatment changes were still satisfied with the result 2 years after debonding. Even patients dissatisfied with the effect of posttreatment changes do not necessarily want retreatment.

Effects of fixed retainers on gingival recession - a 10-year retrospective study.

OBJECTIVE: The aetiology of gingival recessions is not fully understood, and no evidence has yet emerged of a single predisposing factor that instigates this apical shift of the gingival margin. Nonetheless, both fixed retainers and orthodontic treatment have been cited as potential risk factors. The aim of this study was to assess the effects of orthodontic treatment and orthodontic fixed retainers on gingival recessions. SUBJECTS AND METHODS: In total, 105 patients at the Department of Orthodontics at the University of Gothenburg who had undergone orthodontic treatment between 1995 - 2003 were included in this study. Intraoral photographs of the anterior segment and study casts acquired at baseline (pre-treatment), post-treatment and at the 10-year follow-up were used as recorded measurements of gingival recession and orthodontic treatment. At the 10-year follow-up, the patients were divided into two groups based on: long-term (10 years) presence of a fixed retainer [orthodontic treatment and retainer (OR) group; N = 76]; and short-term (<5 years) presence of a fixed retainer [orthodontic treatment (O) group; N = 57]. These groups were compared to a control group (C) of untreated subjects (N = 29). RESULTS: In the anterior segment, gingival recessions were not present at baseline and post-treatment between the two orthodontically treated groups. At the 10-year follow-up, there was no statistically significant difference between the two orthodontically treated groups and the controls. CONCLUSIONS: Orthodontic treatment per se does not increase the risk for gingival recessions, nor does the use of fixed retainers following orthodontic treatment.

Stability, survival, and patient satisfaction with CAD/CAM versus conventional multistranded fixed retainers in orthodontic patients: a 6-month follow-up of a two-centre randomized controlled clinical trial.

OBJECTIVES: The primary aim of this two-arm parallel two-centre randomized controlled trial was to compare computer-aided design and computer-aided manufacturing (CAD/CAM) versus conventional multistranded fixed retainers (FRs) in terms of stability over 6 months. Secondary outcomes were failure rates and patient satisfaction. METHODS: Patients were randomized to CAD/CAM or conventional FRs in both arches, in 1:1 ratio and blocks of four. Allocation concealment was secured by using sequentially numbered envelopes. Patients were blinded. Retainers were bonded at the end of orthodontic treatment (T0), and patients were recalled after 1 (T1), 3 (T3), and 6 (T6) months. First-time retainer failures were recorded and digital impressions were taken. Arch widths and lengths, as well as Little's Irregularity Index (LII), were measured. Additionally, patients answered satisfaction questionnaires. Linear mixed models were applied for measurements and patient satisfaction. Survival analyses were estimated with Kaplan-Meier curves, along with Cox-regression modelling. RESULTS: One hundred and eighty-one patients were randomized (98 in Centre 1, and 83 in Centre 2): Ninety in the CAD/CAM group and 91 in the conventional group. Three subjects dropped out at baseline, as they did not attend any of the follow-up appointments.168 patients attended the T6 visit. There were no significant differences in arch dimensions between T0 and T6, whilst the LII was different only in the CAD/CAM group (mean difference: 0.2 mm; 95% confidence interval: 0.1 to 0.4; P < 0.001). Within 6 months, 39 upper retainers (19 out of 88 CAD/CAM and 20 out of 90 conventional retainers) and 52 lower retainers failed (26 out of 88 CAD/CAM and 26 out of 90 conventional retainers), with no significant difference between the survival of both types of retainers (hazard ratios conventional to CAD/CAM: upper arch: 0.99 [P =0.99], lower arch: 0.93 [P = 0.80]). There were no significant changes in patient satisfaction between the groups. No harms were observed. CONCLUSIONS: There were no clinically significant differences in LII, arch widths and lengths between CAD/CAM and conventional retainers after 6 months. There was no difference in failures and in patient satisfaction between both types of FRs. REGISTRATION: ClinicalTrials.gov NCT04389879.

Post-treatment stability after 5 years of retention with vacuum-formed and bonded retainers-a randomized controlled trial.

BACKGROUND: Retention after orthodontic treatment is still a challenge and more evidence about post-treatment stability and patients' perceptions of different retention strategies is needed. OBJECTIVES: This trial compares removable vacuum-formed retainers (VFR) with bonded cuspid-to-cuspid retainers (CTC) after 5 years of retention. TRIAL DESIGN: A single centre two-arm parallel-group randomized controlled trial. METHODS: This trial included 104 adolescent patients, randomized into two groups (computer-generated), using sequentially numbered, opaque, and sealed envelopes. All patients were treated with fixed appliances in both jaws with and without tooth extractions. Patients in the intervention group received a VFR in the mandible (n = 52), and patients in the active comparator group received a CTC (n = 52). Both groups had a VFR in the maxilla. Dental casts at debond (T1), after 6 months (T2), after 18 months (T3), and after 5 years (T4) were digitized and analysed regarding Little's Irregularity Index (LII), overbite, overjet, arch length, and intercanine and intermolar width. The patients completed questionnaires at T1, T2, T3, and T4. RESULTS: Post-treatment changes between T1 and T4 in both jaws were overall small. In the maxilla, LII increased significantly (median difference: 0.3 mm), equally in both groups. In the mandible, LII increased significantly in the group VFR/VFR (median difference: 0.6 mm) compared to group VFR/CTC (median difference: 0.1 mm). In both groups, overjet was stable, overbite increased, and arch lengths decreased continuously. Intercanine widths and intermolar width in the mandible remained stable, but intermolar width in the maxilla decreased significantly. No differences were found between groups. Regardless of retention strategy, patients were very satisfied with the treatment outcome and their retention appliances after 5 years. LIMITATIONS: It was not possible to perform blinded assessments of digital models at follow-up. CONCLUSIONS: Post-treatment changes in both jaws were small. Anterior alignment in the mandible was more stable with a bonded CTC retainer compared to a removable VFR after 5 years of retention. Patients were equally satisfied with fixed and removable retention appliances. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03070444).

Survival and failure rate of lower lingual bonded retainers: A retrospective cohort evaluation.

OBJECTIVE: The objectives of the study were to evaluate the survival rates for lower lingual retainers (LLRs) and to establish a correlation between patients' treatment-related factors (age, sex, malocclusion, appliance used for treatment, teeth bonded, retention protocols) to the survival of LLRs. MATERIALS AND METHODS: A total of 765 subjects [474 females and 291 males: mean age = 24.29 ± 10.67 years] between 2013 and 2022 were included. A customized data collection form was utilized to gather the data from the electronic health record (EHR) of subjects. Patient-related factors, crowding or spacing, deep bite or open bite and duration of treatment were extracted from patients' files. Kaplan-Meier estimator was used for the survival function, whereas Cox proportional hazards regression models were used to associate risk factors with retainer survival. RESULTS: 328 (42.9%) subjects had their LLRs failed, and the survival period was on average 17.37 ± 22.85 months. On the other hand, the follow-up period for the retainers that did not fail was on average 47.19 ± 23.66 months. 192 (28.3%) subjects had segment failure (retainer detached from 3 teeth or less), while 51 (7.5%) subjects had failures in more than 3 teeth (complete). None of the evaluated clinical variables were significantly associated with LLRs failure except for the bite category (P = .013) and the appliance used for treatment (P < .001). CONCLUSION: Success rate for LLRs was 57.1% over 47.19 months, failure rate was 42.9% over 17.37 months. The presence of deep bite and treatment with aligners were significantly associated with increased failure rate.

Do orthodontic treatments using fixed appliances and clear aligner achieve comparable quality of occlusal contacts?

Design Non-randomised cohort study.Cohort selection The inclusion criteria comprised patients who finished their comprehensive orthodontic treatment based on a camouflage non-extraction modality using self-ligating orthodontic appliances therapy (SPEED brackets, Canada or Empower brackets, American Ortho, Sheboygan, WI, USA) or clear aligner therapy (Invisalign, Align Technology, San Jose, CA, USA). Patients were recruited from a university orthodontic clinic and a senior orthodontist's practice. The exclusion criteria comprised patients presenting with hypodontia, microdontia, severe periodontal problems, heavily resorted teeth and patients who were using retainers with occlusal coverage.Data analysis Included patients were assessed at three points in time: at the end of active orthodontic treatment and the start of retention phase (T0); at three months post treatment (T3); and at six months post treatment (T6). The following three assessments were done for each patient at T0, T3 and T6: a T-Scan 10 digital occlusal analysis recording into maximum intercuspation position (MIP); self-report about retainer compliance; and self-assessment of occlusal comfort using a visual analogue scale (VAS) ranging from 0-10 (0 = very uncomfortable; 10 = maximum comfort).The digital occlusal analysis was performed using a 100µ thin, flexible, horseshoe-shaped Mylar sensor (Novus HD sensor, Tekscan Inc, S. Boston, MA, USA). This sensor contains 1,370 active pressure sensing cells, known as sensels, arranged in a compact grid, shaped as a dental arch. The patients were given instructions on how to bite on the sensor. With the sensor still in the patient's mouth, three consecutive self-intercuspated closure-into-MIP registrations were recorded. If there was a need to repeat the procedure, one minute was given as a rest. If several recordings were done for the same patient in the same visit, the most consistency between the three consecutive intercuspations was used for analysis. In addition, the same sensor was used in T0, T3 and T6, unless the sensor shown excessive wear.The following outcomes were assessed using the digital occlusal analysis: 1) an estimate of occlusal contact surface area based on the activated sensels on the sensor at MIP; 2) the total surface of contacts and the area ratio between anterior (canine to canine) to posterior (premolar to second molar) contact surfaces; 3) the overall relative force distribution based on the by the position of the centre of force (COF); 4) the symmetry of contact distribution was expressed as the percentage of contacts on the right side to the left side (%R/L); and 5) the time-simultaneity of the closure into MIP contacts was calculated by the occlusion time measurement which is the duration between first contact and the time MIP was reached.Results In total, 39 patients were enrolled in the study. The self-ligating fixed appliance group included 25 patients (mean age 18.7 ± 5.2; 6 women, 19 men) while the clear aligner therapy group included 14 patients (mean age 20.6 ± 7.3; ten women, four men). Both groups were matched in terms of age, Angle's classification, symmetry, retention protocol and total number of bonded lingual wires or facial type. However, they were not matched in terms of sex, with more women in the aligner group (p = 0.007). Moreover, eight patients (four in each group) were excluded from the study later on due to a change in the retention protocol or a missed visit. The results showed that self-reported compliance with a Hawley retainer was not different between groups. Occlusal comfort was similar in both groups at treatment completion, with a median score of eight in both groups.The results showed that were no statistically significant differences between the two groups regarding all outcomes assessed using the digital occlusal analysis. Although the %R/L (normal range = 50% ± 5%) was not significantly different between both groups, neither treatment resulted in ideal occlusal balance (ie symmetry). Indeed, ten patients finished their treatment with subtle asymmetry (%R/L >50 ± 10%), especially in the self-ligating fixed appliance group (nine patients) showing side force differences (five right dominant, four left dominant) versus only one patient in the clear aligner group (left dominant).The COF moved posteriorly in both groups from T0 to T6, in parallel with a decreased ratio of anterior to posterior surface area. A statistically significant difference was observed in the anteroposterior position of COF between sexes, being more anterior in women at all times (p <0.002).Conclusions The quality of the occlusal contacts in MIP was comparable in both groups at T0, T3 and T6. Neither treatment resulted in an ideal occlusal balance (that is, symmetry). Ten patients finished their treatment with subtle occlusal force asymmetry (that is, asymmetric left-to-right side occlusal force distribution), especially in the self-ligating fixed appliance group. Most occlusal changes happened during the first three months of the retention phase, with more posterior contacts forces developing in both groups. In this study, female patients maintained more anterior COF when compared to male patients.

External Root Resorption of Second Molars Due to Impacted Mandibular Third Molars during Orthodontic Retention.

Whether there is a relationship between impaction of the third molars and the onset of crowding remains to be determined, and extraction of third molars after orthodontic treatment is left to the judgement of the practitioner. This report describes a case where a third molar caused external root resorption (ERR) of the mandibular second molar after orthodontic treatment. As ERR of the mandibular second molar was detected after non-extraction orthodontic treatment, the affected tooth was extracted and substituted with the third molar. External root resorption of the second molar occurred despite being determined as low risk given the state of the impacted third molar as observed on a panoramic radiograph obtained at the end of active treatment. The present results indicate that in cases where the mandibular third molar is present, the corpus length is short, and non-extraction treatment has been performed, it is necessary to obtain X-ray images on a regular basis or preventively extract the third molar to avoid ERR of the second molars.

Survival analysis of three types of maxillary and mandibular bonded orthodontic retainers: a retrospective cohort.

BACKGROUND: Retention is an important aspect of orthodontic treatment. This study aimed to analyze the survival of three types of maxillary and mandibular bonded orthodontic retainers. METHODS: This retrospective cohort study evaluated the records of 118 orthodontic patients (90 females, 28 males, mean age of 22.34 ± 6.44 years) retrieved from a private orthodontic office. Data regarding the retainer failure, dental caries, unwanted tooth movements, maximum pocket depth (PD), and bleeding on probing (BOP) recorded at the follow-up sessions were extracted from patient records. Three types of retainer wires namely Bond-A-Braid, Orthoflex, and Retainium were compared regarding the abovementioned parameters. Data were analyzed by ANOVA, Chi-square, Monte-Carlo Chi-square, and Kruskal Wallis tests, the log rank test, and the Cox regression model. RESULTS: The frequency of retainer failure was not significantly different between males and females, different age groups, or different treatment durations (P > 0.05). Wire fracture was the most common failure type in both the maxilla and mandible. Also, the frequency of failure was not significantly different between the maxillary and mandibular retainers (P > 0.05). The frequency of failure, and survival of the three types of retainer wires were not significantly different during a 5-year period (P > 0.05). CONCLUSIONS: The three types of orthodontic retainers had comparable survival rates. Their failure rate was not correlated with the age or gender of patients or the treatment duration.

Indirect vs direct bonding of mandibular fixed retainers in orthodontic patients: Comparison of retainer failures and posttreatment stability. A 5-year follow-up of a single-center randomized controlled trial.

INTRODUCTION: This 2-arm parallel trial aimed to assess the number of failures of mandibular fixed retainers bonded with direct and indirect bonding methods at a 5-year follow-up and investigate the stability of intercanine and interpremolar distances. METHODS: Consecutive patients from the clinic of the University of Geneva (Switzerland) were randomly allocated to either direct or indirect bonding of a mandibular fixed retainer at the end of orthodontic treatment. Inclusion criteria included the presence of all mandibular incisors and canines; and the absence of active caries, restorations, fractures, or periodontal disease of these teeth. The patients were randomized in blocks of 4 using an online randomization service, with allocation concealment secured by contacting the sequence generator for assignment. Two and 5 years (T5) after bonding the retainers, the patients were recalled, and impressions were taken. The primary outcome was the 5-year survival of the mandibular fixed retainer bonded with both bonding methods. The secondary outcomes were the intercanine and interpremolar distances and the assessment of unexpected posttreatment changes (ie, changes in torque and/or rotations of the mandibular incisors and canines). Blinding was applicable for outcome assessment only. Kaplan-Meier curves were generated, and a Cox proportional hazard regression model was fitted for bonding type, age, and treatment. Linear mixed models were fitted to intercanine and interpremolar distances: bonding type, time, age, and treatment were modeled as outcomes. RESULTS: Sixty-four patients were randomized in a 1:1 ratio. At T5, 6 patients without previous failure were lost to follow-up from each group. At T5, the fixed retainer was debonded in 14 patients (54%) for each group. The hazard ratio of indirect bonding to direct bonding was 1.09 (95% confidence interval, 0.26-4.60; P = 0.91); there was no statistically significant difference in survival between the groups. Regarding intercanine and interpremolar distances, none of the tested prognostic factors reached statistical significance. Unexpected posttreatment changes were observed in 6 failure-free patients, all bonded with the direct bonding method. Only 1 patient required debonding of the fixed retainer. No other serious harms were observed. CONCLUSIONS: The 5-year survival rate for both direct and indirect bonding methods was 46%, without a statistically significant difference between bonding methods. Bonded retainers were effective in maintaining intercanine and interpremolar distances. Unexpected posttreatment changes were only observed with retainers bonded with the direct bonding method. REGISTRATION: The trial was not registered. PROTOCOL: The protocol was not published before trial commencement. FUNDING: No funding or conflict of interest to be declared.

Patient-Reported Outcome Measures on Oral Hygiene, Periodontal Health, and Treatment Satisfaction of Orthodontic Retention Patients up to Ten Years after Treatment-A Cross-Sectional Study.

Background: This cross-sectional study evaluated patient-reported outcome measures (PROMs) on (1) oral hygiene, (2) periodontal health, (3) retainer failure, (4) orthodontic treatment satisfaction, and (5) outcome satisfaction in orthodontic retention patients. The purpose of the study was to evaluate whether orthodontic retention treatment is associated with patient-reported outcome measures on oral hygiene, periodontal health, and treatment satisfaction. Methods: A ten-item questionnaire on the five PROMs was conducted among 211 consecutive retention patients up to ten years following orthodontic treatment. Linear regression models were computed to detect possible associations between the PROMs and retention treatment or patient characteristics. Results: The presence of a fixed lingual retainer was not associated with the reduced ability to perform oral hygiene, self-perceived periodontal health, or orthodontic outcome satisfaction. Older patients were more content with the orthodontic treatment result (p < 0.05). Patients with fixed lingual retainers in the mandible were less satisfied with the course of orthodontic treatment (p < 0.05). Smokers more often reported gingival bleeding (p < 0.05). Females reported increased gingival recessions (p < 0.05) and perceived their teeth as longer than before treatment (p < 0.05). Longer orthodontic treatment duration corresponded to retainer failure (p < 0.05). Conclusions: In general, long-term orthodontic retention patients were satisfied with orthodontic treatment. These patients reported the satisfactory ability to perform adequate oral hygiene and periodontal health, and they communicated a high degree of treatment and outcome contentment. However, patients with a retainer in the mandible were less satisfied with orthodontic treatment.

The Impact of Orthodontic Retainers on Gingival Recession: A Best-Evidence Review.

Retention is a critical phase of orthodontic therapy and aims to maintain occlusal stability and avoid crowding relapse. This best-evidence article reviews the effects of the different types of orthodontic retention appliances, fixed and removable, on the development and progression of gingival recession at the mandibular anterior teeth. Searched databases included PubMed, Scopus, Cochrane Library, Embase, and Dentistry and Oral Sciences. Eleven qualifying publications, including retrospective, prospective, and cross-sectional studies, were included in this review. These studies either did not demonstrate an association between orthodontic retainers and gingival recession or reported that the resulting recession defects were minimal when an association was shown. An important consideration is that recession could be a late finding following the placement of a retainer and, therefore, may be incipient or absent in short-term evaluations. Prospective studies that specifically address the role that properly positioned fixed retainers may have on gingival recession are needed before a definitive conclusion can be generalized with regard to recommended retention protocols. Factors such as duration of retainer use, number of bonded teeth, and position of fixed retainers relative to their proximity to gingival tissues are not fully elucidated but may have influencing roles on gingival recession. The use of retainers should be based on orthodontic indications to maintain a stable dental arch form, esthetics, and occlusion. Effective oral hygiene and follow-up regimens remain the gold standard in maintaining periodontal health and preventing gingival recession.

[The quality of life of patients after orthodontic treatment depending on the use of different types of retention appliances]. / Kachestvo zhizni patsientov posle ortodonticheskogo lecheniya v zavisimosti ot ispol'zovaniya razlichnykh vidov retentsionnykh apparatov.

AIM: To assess the impact of the type of retention device on the quality of life of orthodontic patients. MATERIAL AND METHODS: 311 patients were divided into four groups according to age. At the end of active orthodontic treatment, retainers were installed. After 6 months, a questionnaire was conducted using the standard OHIP-14 questionnaire in order to identify the attitude to the equipment used, the presence or absence of relapses and satisfaction with the state of the dental system. RESULTS: The number of relapses in all groups is approximately at the same level, which indicates almost equal opportunities for retainers to retain the achieved result. There is no correlation between the convenience of using a particular type of retainer and the willingness to do so. CONCLUSION: The motivation of patients to use removable or non-removable retention devices to a certain extent depends not only on the type of retainer, but also on the age at which the treatment was performed.