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Journal of Oral Science Apr 2024To investigate the elemental composition, corrosion resistance, and mechanical properties of computer-aided design and computer-aided manufacturing (CAD-CAM) retainers...
Elemental composition, corrosion resistance and mechanical properties of computer-aided design and computer-aided manufacturing fixed retainers versus conventional fixed retainers.
PURPOSE
To investigate the elemental composition, corrosion resistance, and mechanical properties of computer-aided design and computer-aided manufacturing (CAD-CAM) retainers versus conventional fixed retainers (FRs).
METHODS
Eight different retainer wires were investigated. Energy dispersive X-ray spectroscopy was used to determine the elemental composition. Leakage was analysed according to ISO 10271:2020 guidelines. Hardness was tested using the Vickers method with a load of 0.3 kg. The tensile force and tensile strength were evaluated. Multiple comparisons among wires of hardness, tensile force, and strength were conducted using the Welch t-test, with Bonferroni correction.
RESULTS
Nickel was present in all wires. The CAD-CAM-FR wire, which contained more nickel than the other wires, had no measurable leakage. The gold-plated wires had the highest total leakage, but did not exceed the ISO standard limit. The hardness of the stainless-steel twisted wires was the highest and that of the CAD-CAM-FR wire was the lowest. The tensile strength of the CAD-CAM-FR wire was significantly lower than that of the other wires and similar to the other twisted-wire retainers.
CONCLUSION
The CAD-CAM-FR wire is likely to have high corrosion resistance and flexibility due to its low hardness.
Topics: Corrosion; Nickel; Orthodontic Retainers; Orthodontic Wires; Orthodontic Appliances, Fixed; Computer-Aided Design
PubMed: 38403676
DOI: 10.2334/josnusd.23-0303 -
European Journal of Orthodontics Apr 2024CAD/CAM (computer-aided design/computer-aided manufacturing) fixed retainers (FRs) as an alternative to multistranded FRs to maintain orthodontic treatment outcome. (Randomized Controlled Trial)
Randomized Controlled Trial
Stability, survival, patient satisfaction, and cost-minimization of CAD/CAM versus conventional multistranded fixed retainers in orthodontic patients: a 2-year follow-up of a two-centre randomized controlled trial.
BACKGROUND
CAD/CAM (computer-aided design/computer-aided manufacturing) fixed retainers (FRs) as an alternative to multistranded FRs to maintain orthodontic treatment outcome.
OBJECTIVES
The primary aim was to compare CAD/CAM versus conventional multistranded FRs in terms of stability until 2 years. Secondary outcomes were failure rates, patient satisfaction, and cost-minimization.
TRIAL DESIGN
2-arm parallel, two-centre randomized controlled trial.
METHODS
Patients were randomized to CAD/CAM or conventional FRs in both arches, in a 1:1 ratio and blocks of four. Allocation concealment was secured by using sequentially numbered envelopes. Patients were blinded. FRs were bonded at the end of treatment, and patients were recalled after 12 and 24 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. Cost-minimization analysis was undertaken.
RESULTS
One hundred and eighty-one patients were randomized (98 in Centre 1, and 83 in Centre 2): 90 in CAD/CAM and 91 in conventional group. One hundred and fifty three patients attended T24 follow-up. There were no significant differences in LII and arch dimensions between groups for failure-free patients. Within 24 months, 34% maxillary CAD/CAM FRs and 38% maxillary conventional FRs failed, along with 42% mandibular CAD/CAM FRs and 40% mandibular conventional FRs, with no significant difference in survival between groups (hazard ratios conventional to CAD/CAM: maxillary arch: 1.20 [P = 0.46], mandibular arch: 0.98 [P = 0.94]). There were no significant differences in patient satisfaction between groups. No harms were observed. Cost-minimization analysis showed that CAD/CAM FRs were slightly cheaper than conventional FRs.
CONCLUSIONS
There were no clinically significant differences in LII, arch widths, and lengths between CAD/CAM and conventional FRs after 24 months. There were no differences in failures and patient satisfaction between groups. CAD/CAM FRs were slightly cheaper than conventional FRs.
TRIAL REGISTRATION
ClinicalTrials.gov NCT04389879.
Topics: Humans; Patient Satisfaction; Follow-Up Studies; Orthodontic Retainers; Orthodontic Appliance Design; Orthodontic Appliances, Fixed
PubMed: 38394353
DOI: 10.1093/ejo/cjae006 -
BMC Oral Health Feb 2024Aim of this randomized clinical controlled trial was to evaluate the influence of fixed orthodontic steel retainers on gingival health and recessions of mandibular... (Randomized Controlled Trial)
Randomized Controlled Trial
Influence of fixed orthodontic steel retainers on gingival health and recessions of mandibular anterior teeth in an intact periodontium - a randomized, clinical controlled trial.
OBJECTIVE
Aim of this randomized clinical controlled trial was to evaluate the influence of fixed orthodontic steel retainers on gingival health and recessions of mandibular anterior teeth.
MATERIALS AND METHODS
After end of the orthodontic treatment, patients were randomly assigned into the test (fixed steel retainer) or control group (modified removable vacuum-formed retainer). Periodontal parameters (periodontal probing depth: PPD; recession: REC; bleeding on probing: BOP) as well as plaque and gingival index were assessed on mandibular anterior teeth directly before attaching/handing over the retainer (baseline: BL), 6 and 12 months after orthodontic treatment.
RESULTS
37 patients (test: n = 15, mean age: 16.1±4.2 years; control: n = 17, mean age: 17.1±5.4 years) completed the study. REC and PPD failed to show significant pairwise differences. The number of patients showing gingival health in the area of the mandibular anterior teeth (test: BL n = 10, 6 months n = 9, 12 months n = 11; control: BL n = 10, 6 months n = 16, 12 months n = 15) revealed a significant difference for the intra-group comparison between BL and 6 months in the control group (p = 0.043). The inter-group comparisons failed to show significant differences.
CONCLUSION
Young orthodontically treated patients with fixed steel retainers show in 73.3% healthy gingival conditions after one year which are comparable to the control group (88.2%). Gingival recessions were in a clinically non-relevant range at any time of the examination.
CLINICAL TRIAL NUMBER
DRKS00016710.
Topics: Humans; Child; Adolescent; Young Adult; Adult; Steel; Gingiva; Periodontium; Gingival Diseases; Gingival Recession; Orthodontic Appliance Design
PubMed: 38355505
DOI: 10.1186/s12903-024-03998-0 -
European Journal of Paediatric Dentistry Mar 2024The integrity of primary dentition is essential in the development of the jaws and permanent occlusion. The consequences of a premature loss of primary molars are: space... (Review)
Review
AIM
The integrity of primary dentition is essential in the development of the jaws and permanent occlusion. The consequences of a premature loss of primary molars are: space loss, crowding, risk of impaction of the permanent teeth, ectopic eruption, anomalous inclination of the teeth adjacent to the loss molar, reduction of arch length. The mesial displacement of the posterior permanent teeth during eruption can cause a loss of space, which can be regained with orthodontic appliances. Therefore, a careful diagnosis is of great importance to be able to decide what appliance is indicated to recover from this situation. Molar distalisation consists in displacing permanent molars distally, allowing them to reach class I relationship and to recover the correct space for the second bicuspids when the second deciduous molar has been lost early.
METHODS
The aim of this study is to carry out a narrative literature review regarding the different appliances and their effectiveness in regaining space after premature loss of the upper primary molars.
CONCLUSION
The paediatric dentist should be aware of the advantages and disadvantages related to each device and select the most appropriate distalisation appliance based on an individual plan of diagnosis and a careful treatment. The distalisation of the upper molar must be adequately stabilised and so it is important to consider also some retainers such as Nance's appliance, the Palatal Plate, the extraoral traction, the utility arch, or II Class elastic bands.
Topics: Child; Humans; Molar; Tooth Eruption; Malocclusion; Dentition, Permanent; Tooth, Impacted
PubMed: 38353522
DOI: 10.23804/ejpd.2024.2110 -
Cureus Jan 2024Orthodontists, like any other medical professional, are susceptible to cumulative stressors and their undesirable consequences. The study aims to assess the...
BACKGROUND
Orthodontists, like any other medical professional, are susceptible to cumulative stressors and their undesirable consequences. The study aims to assess the self-perceived occupational stress levels and the psychological link between predictors and stress among orthodontic practitioners in India.
MATERIALS AND METHODS
The participants in this cross-sectional study are active members of the Indian Orthodontic Society (IOS). The data for the survey were collected by a previously validated closed-ended occupational stress assessment (OSA) questionnaire and a job satisfaction questionnaire, which were sent through the registered e-mails. A five-point Likert scale was used to assess the severity of individual stressors, and an overall severity score was obtained by summing up the individual scores. The predictors of stress based on socio-demographic parameters were assessed using a binomial multiple logistic equation. Statistical significance was set at a p-value of <0.05.
RESULTS
A total of 311 responses were received. Male orthodontists, unmarried, in the age group of 30-40 years, working in urban areas without any academic attachment were more stressed compared to the other groups in the respective categories. Tiredness/headache (39%) was reported as the most common consequence of occupational stress. The most concerning stressor was patients not wearing retainers. Orthodontists showed overall job satisfaction that is negatively correlated to overall stress (p <0.0001)(r = -0.260).
CONCLUSION
A profound variation in stress levels was found among the orthodontists with their socio-demographic and professional characteristics. Despite the stress, orthodontists were highly satisfied with their careers.
PubMed: 38352100
DOI: 10.7759/cureus.52266 -
European Journal of Orthodontics Apr 2024
PubMed: 38345244
DOI: 10.1093/ejo/cjae007 -
The Angle Orthodontist Dec 2023To explore retainer protocols and how they are influenced by orthodontic presentation and the nature of occlusal correction.
OBJECTIVE
To explore retainer protocols and how they are influenced by orthodontic presentation and the nature of occlusal correction.
MATERIALS AND METHODS
A prepiloted 45-item online questionnaire targeting orthodontists was developed. The questionnaire covered clinical preferences in terms of retainer type, fabrication, and follow-up during retention; the clinical indications for adjunctive surgical procedures; and the use of active designs to mitigate relapse in specific malocclusions.
RESULTS
A total of 206 responses were obtained. The majority of the respondents prescribed maxillary removable and mandibular fixed retainers, with almost half (49.1%) reviewing patients for more than 1 year primarily in person (95.1%). The majority prescribed vacuum-formed (69.6%) 1-mm-thick (44.3%) retainers. Only 37.3% were aware of the type of material used, with polyethylene terephthalate glycol copolymer, followed by polypropylene, being the most common. Hawley retainers were preferred following nonsurgical maxillary expansion and with suboptimal interdigitation. A preference for clear retainers and/or fixed retainers was found in open-bite cases and deep-bite cases. Supracrestal fiberotomy was prescribed commonly (61.1%) for rotations greater than 90°. No retainer was rarely prescribed except after the correction of an anterior crossbite.
CONCLUSIONS
Blanket prescription of orthodontic retention is common, with limited awareness of clear plastic retainer materials. Future trials evaluating the effectiveness of approaches for retainer prescription based on the presenting malocclusion would be timely.
PubMed: 38319063
DOI: 10.2319/060923-400.1 -
Journal of Dental Sciences Jan 2024Preserving the outcome of orthodontic treatment is both important and challenging. However, there is insufficient evidence regarding the best way to ensure long-term...
BACKGROUND/PURPOSE
Preserving the outcome of orthodontic treatment is both important and challenging. However, there is insufficient evidence regarding the best way to ensure long-term treatment outcome. The aim of this study was to evaluate a pre-fabricated chain retainer (PFCR) in terms of: ability to maintain satisfactory treatment outcomes; periodontal and dental health; complications; and patient satisfaction.
MATERIALS AND METHODS
Overall, 130 patients who had completed orthodontic treatment with a fixed appliance during the period 2016-2019 (follow-up time range, 24-55 months) at a specialist orthodontic clinic in Varberg, Sweden and who had a PFCR in the lower jaw were invited to take part in the study. Little's irregularity index (LII) was recorded on dental casts. Caries, gingivitis, calculus, probing pocket depth, and gingival retractions were registered during clinical examinations. Patient satisfaction and retainer complications were evaluated using a questionnaire.
RESULTS
In total, 76 patients (58.5%) agreed to participate. All patients, except for one, had their retainer still in place, and the complication rate was 40%. The LII scores were in the range of 0-4 mm (mean, 1.42 mm). At the retainer site, 82% had calculus, 74% had gingivitis, 1% had pocket depth >4 mm, 10.5% had gingival retractions >2 mm, and 0% had caries. All the patients expressed satisfaction with their retainer.
CONCLUSION
PFCRs exhibit characteristics similar to those of traditional bonded retainers in terms of complications, stability, side-effects and patient experience. Therefore, they can be considered a viable alternative to traditional retainers installed in the lower anterior teeth.
PubMed: 38303849
DOI: 10.1016/j.jds.2023.05.020 -
BMC Oral Health Jan 2024Parallel. (Randomized Controlled Trial)
Randomized Controlled Trial
Cephalometric and digital model analysis of dentoskeletal effects of infrazygomatic miniscrew vs. Essix- anchored Carriere Motion appliance for distalization of maxillary buccal segment: a randomized clinical trial.
TRIAL DESIGN
Parallel.
OBJECTIVE
To compare skeletally anchored Carriere Motion appliance (CMA) for distalization of the maxillary buccal segment vs. Essix anchored CMA.
METHODS
Thirty-two class II malocclusion patients were randomly allocated into two equal groups. One group was treated with infrazygomatic (IZC) miniscrew- anchored CMA (IZCG) and the other group treated with Essix retainer- anchored CMA (EXG). Two lateral cephalograms and two digital models for upper and lower arches were taken for each patient: immediately before intervention and after distalization had been completed.
RESULTS
Distalization period was not significantly different between the two groups. In contrast to EXG, IZCG showed insignificant difference in ANB, lower incisor proclination, and mesial movement of the lower first molar. There was significant rotation with distal movement of maxillary canine and first molar in both groups.
CONCLUSION
IZC anchored CMA could eliminate the side effects of class II elastics regarding lower incisor proclination, mesial movement lower molars with a more significant amount of distalization of the maxillary buccal segment but with significant molar rotation.
TRIAL REGISTRATION
The ClinicalTrials.gov Protocol Registration and Results System (PRS) has this RCT registered as (NCT05499221) on 12/08/2022.
Topics: Humans; Treatment Outcome; Tooth Movement Techniques; Maxilla; Malocclusion, Angle Class II; Cephalometry; Orthodontic Appliance Design; Orthodontic Anchorage Procedures
PubMed: 38297285
DOI: 10.1186/s12903-024-03925-3 -
BMC Oral Health Jan 2024Retainers are the only effective approach to prevent orthodontic relapse. The aim of this study was to compare the changes in color and light-transmittance of rough and...
BACKGROUND
Retainers are the only effective approach to prevent orthodontic relapse. The aim of this study was to compare the changes in color and light-transmittance of rough and smooth thermoformed polyurethane and copolymer retainer samples after staining in different solutions and destaining with different approaches.
METHODS
Four hundred copolyester (Essix® ACE) and 400 polyurethane (Zendura®) samples with different surface textures, smooth and rough, were stained in 4 different solutions (n = 100 per solution) over 28 days. Each of the four groups of 100 stained samples of each material was subdivided into 5 groups of 20 samples and subjected to different destaining solutions. Light transmittance and color changes were evaluated using a spectrometer and a spectrophotometer. Mean differences were compared using a two-way analysis of variance (ANOVA) and posthoc multiple comparison tests at P = 0.05.
RESULTS
No significant differences in light transmittance were found between both untreated materials. Both materials were stained in a similar fashion and showed no significant differences between two materials after staining. Coffee and tea stained both materials more significantly than wine, but there was a significant difference of changes of color and light transmittance between rough and smooth surfaces during the destaining in coffee- and tea-stained samples of copolyester material. All destaining solutions were effective at removing all stains on the samples. The surface roughness of the material plays a significant role in the ability of the materials to be destained, demonstrating a more significant greater effect on cleaning rough samples for improvements in light-transmittance and greater changes in color.
CONCLUSIONS
This study concluded that the surface of materials plays a significant role in the material destaining and staining. In addition, the different polymers used for retainer fabrication exhibited different responses during the destaining process depending on types of stains.
Topics: Humans; Coffee; Polyurethanes; Spectrophotometry; Staining and Labeling; Coloring Agents; Tea; Materials Testing; Color; Surface Properties; Composite Resins
PubMed: 38297268
DOI: 10.1186/s12903-024-03887-6