European journal of orthodontics最新文献

Objective: The aim of this study was to investigate the electrochemical characteristics and ionic release of three-dimensional (3D) printed orthodontic metallic bands made of stainless-steel (SS) and Cobalt-Chromium (Co-Cr) alloys.

Materials and methods: Thirty-six orthodontic metallic bands were prepared by 3D printing, employing SS (n = 18) and Co-Cr (n = 18) alloys. The ionic release from each alloy was determined according to ISO 27020:2019 requirements employing flame atomic absorption spectrometry (FAAS). The electrochemical properties were characterized by Open Circuit Potential (OCP), Anodic Scan (AS) and Electrochemical Impedance Spectroscopy (EIS). In all cases a 0.1M NaCl, 0.1 M lactic acid solution was used. The EIS data were fitted to a Randles circuit and the sum of ionic release of probed elements after immersion along with OCP, zero corrosion potential (Ecorr), corrosion current density (Icorr), and pitting corrosion potential (Epit) were compared with t-tests/Mann-Whitney tests (α = 0.05).

Results: SS bands showed an approximately 44-fold higher total ionic release compared to Co-Cr ones. Electrochemical testing revealed no statistically significant differences for Ecorr but Co-Cr illustrated more beneficial OCP, Icorr and Epit values than SS. Both alloys illustrated semicircles in Nyquist plots, implying that the electrochemical process was under charge transfer control, while the equivalent circuit simulation showed a higher charge transfer resistance for Co-Cr alloy (SS:14191.1 vs Co-Cr:33158.7 Ωcm2), implying lower corrosion current and thus decreased corrosion rate.

Conclusion: Immersion and electrochemical testing indicated that Co-Cr alloys showed increased corrosion resistance over SS ones, which might affect efficacy under clinical use.

Background: In many European countries, orthodontic treatment is offered in publicly funded healthcare to those with severe malocclusion. In the Finnish public health care, the modified Grainger's treatment priority index (TPI) is used to determine malocclusion severity and treatment eligibility. The uniform use of occlusal indexes is crucial for equitable treatment allocation.

Objective: This study aimed to investigate equity in access to orthodontic care in one wellbeing services county in Finland.

Materials and methods: We conducted five calibration events, where five orthodontists were calibrated against one gold standard orthodontist with the longest clinical experience. All the orthodontists independently clinically examined random groups of patients using the Finnish modified TPI scoring. The malocclusion severity scores, diagnosis codes, and the determined treatment eligibility were subsequently compared. Agreement between the orthodontists was analyzed with Cohen's Kappa and Bland-Altman statistics.

Results: In total, 166 patients, aged 6-63 years, were examined across the calibrations, each representing a comparison between one of the five orthodontists and the gold standard. The agreement between the orthodontists was found to be substantial. The same judgement on treatment eligibility was made in 145 out of 166 cases (87%), whereas a different decision on treatment eligibility was made in 21 cases (13%).

Conclusions: Despite the high level of interobserver agreement, differences in eligibility judgement were observed, which may have important consequences for the patient with respect to treatment provision. Therefore, systematic calibration and regular training in the use of national occlusal indexes should be implemented for all orthodontists.

Background/objectives: Gingival recession results from the displacement of the gingival margin apically to the cementoenamel junction. There is unclear evidence regarding the impact of orthodontic treatment on the development of gingival recessions. The aim of this study was to investigate the changes in clinical crown length and the development of gingival recession on the labial aspect of the maxillary and mandibular incisors associated with orthodontic treatment and relate these changes to the observed variations in their sagittal inclination.

Materials/methods: Eighty-two consecutive subjects treated with fixed orthodontic appliances in both dental arches, possessing high-quality pre- and post-treatment dental casts and lateral cephalometric radiographs, were selected from the archives of a private orthodontic clinic. Incisor clinical crown lengths before and after orthodontic treatment, as well as the presence or absence of recession, were measured using digitized study models. Changes in sagittal inclination were assessed from lateral cephalometric radiographs and categorized as proclination, retroclination, or no change (± 1°). Spearman's correlation coefficient, one-way analysis of variance, and chi-square tests were utilized for analysis.

Results: The mean change in clinical crown lengths for the maxillary incisors ranged from -0.24 to 0.01 mm, while for the mandibular incisors, it varied from 0.06 to 0.10 mm. The inclination changes were -1.78° and 1.03°, respectively, but no correlations were found between these inclination changes and the clinical crown length alterations. Overall, no statistically significant differences were observed in clinical crown length changes concerning the presence of gingival recession among the proclination, retroclination, and no change groups.

Limitations: The sample of this study was retrospective and assessments were carried out immediately post-treatment.

Conclusions/implications: The alteration of incisor inclination during treatment did not appear to impact the changes in labial clinical crown length and the development of gingival recession in this specific sample.

Background: An increasing number of adults with periodontitis are pursuing orthodontic treatment to enhance their occlusion and aesthetics. To manage these patients effectively, it is essential to develop a tailored orthodontic treatment plan that addresses key factors such as anchorage, biomechanics, and interdisciplinary collaboration between orthodontists and periodontists. This comprehensive approach can significantly improve treatment outcomes.

Objectives: This study aims to identify the most effective orthodontic protocols for treating patients with periodontitis or a reduced periodontium, paving a foundation for better clinical practices and improved patient satisfaction.

Search methods: The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guideline. Selection Criteria: It focused on patients aged 20-50 years, with no systemic disorders, and studies published since 2000.

Data collection and analysis: Data was collected and the quality was assessed using the Critical Appraisal Skills Program (CASP) checklist. A meta-analysis was performed using the R program, with I2 used to quantify heterogeneity. Sensitivity analysis was performed on each subset of studies.

Results: The sensitivity analysis reveals that orthodontic therapy significantly resulted in improved clinical attachment level (CAL), with a pooled mean gain of 3.84-4.34 mm. Also, a significant reduction in probing depth (PD) with a pooled mean reduction of 4.32 mm was revealed after orthodontic treatment for periodontitis patients .

Conclusion: This study suggested that individualized, interdisciplinary orthodontic and periodontic protocols are crucial for managing patients with periodontitis or reduced periodontium. Tailored approaches using conservative forces and regenerative strategies significantly improve clinical outcomes, making one-size-fits-all methods inadequate.

Registration: PROSPERO: ID: CRD42024573973.

Background: Clinical photography is a fundamental aspect of orthodontic treatment and has become critical to patient care, communication and documentation. Digital Single Lens Reflex (DSLR) cameras with a ring flash have been established as a gold standard for clinical photography for many years, however smartphones are increasingly being utilized by both patients and clinicians due to their convenience, cost effectiveness and good accessibility.

Aims/ objectives: This study compared the image quality, dimensional accuracy, ease of use and accuracy of shade representation of images produced by recent flagship smartphones versus DSLR cameras with a ring flash.

Material and methods: A sample of four recent smartphones and three semi-professional DSLR cameras were compared taking a comprehensive set of orthodontic intra and extra oral clinical photographs. The following outcome measures were assessed for each device: Camera sensor size, image quality, ease of use, dimensional accuracy and colour shade representation.

Results: DSLR cameras with a ring flash were statistically significantly superior to smartphones for camera sensor size, image quality rating and dimensional accuracy. There was no significant difference between all devices for their ease-of-use rating or accuracy of colour shade representation.

Conclusion: Based on the results of this study, the authors recommend the use of DSLR cameras with a ring flash as a gold standard for clinical photography due to reduced quality rating and image distortion produced by many smartphone cameras.

Objective: To analyze changes in patients' temporomandibular dysfunction (TMD) symptoms during orthodontic-surgical treatment and to investigate associations between symptoms, findings in temporomandibular joints (TMJs), satisfaction with occlusal function, psychological distress, and orthognathic quality of life (OQoL).

Subjects and methods: Thirty-six consecutive female patients started orthodontic-surgical treatment, and 28 voluntary controls participated. Patients and controls filled in a semi-structured diary (regarding satisfaction and TMD symptoms) and the Orthognathic Quality of Life Questionnaire (OQLQ); patients also filled in the Symptom Checklist-90 (SCL-90). Patients' data were analyzed before treatment (T1), after preoperative orthodontics (T3), and one year after jaw surgery (T5). Controls' data were collected at respective time points (CT1, CT2, CT3). Magnetic Resonance Imaging (MRI) studies were performed on patients' and controls' TMJs at T1/CT1.

Results: Before surgery, patients reported more TMD symptoms than controls. The most frequent symptoms were head/neck pain, stiffness/fatigue of the jaws, and pain in jaw joints. The most common finding in TMJ-MRI was anterior disc displacement with or without reduction. One year after surgery, improvement was seen in patients' satisfaction and OQLQ scores. Patients' number of symptoms correlated negatively with satisfaction and positively with OQLQ scores. No significant correlations were found between the severity of TMJ-MRI findings and satisfaction, number of symptoms, OQLQ function, or sum score.

Conclusions: Although TMJ-MRI findings are common among orthodontic-surgical patients, they are not always reflected in subjective symptoms, nor in self-perceived treatment outcome. Individual characteristics, not detectable using objective measures, constitute an important aspect and should therefore reserve more emphasis.

Objectives: This study aimed to evaluate zoledronic acid (ZOL) induced alterations in the alveolar bone, periodontal ligament, and cementum under orthodontic forces in mice of different ages, focusing on the early and late half-life of ZOL administration.

Methods: Juvenile (6-week; n = 30) and adult (12-week; n = 20) mice (C57BL/6J) were divided into five groups, with three groups receiving a single ZOL dose. A 0.35 N orthodontic force was applied 1 and 12 weeks after ZOL administration. Alveolar bone, cementum, periodontal ligament response, osteoclast activity, calcium and 1,25(OH)2D3 levels were assessed at 12 h and 12 weeks after force application.

Results: ZOL reduced tooth displacement and osteoclast counts in the adult and juvenile (latency phase of medication) groups compared to the juvenile control group (P < .05). The thickness of the periodontal ligament and number of blood vessels decreased moderately in adult mice and slightly in juveniles (P < .05), particularly in the ZOL-treated groups. Cementum resorption and alveolar crest irregularities were observed in all the ZOL-treated groups. Juvenile mice that underwent force application 12 weeks after ZOL administration exhibited responses similar to those observed in adult mice.

Limitations: This study demonstrated that the periodontal ligament and alveolar bone of juvenile and adult mice respond differently to ZOL treatment. However, the mechanisms underlying these differential effects remain unclear, highlighting the need for further investigation of bone remodeling markers to better understand the impact of ZOL during both the active and latency phases in young and adult subjects.

Conclusions: ZOL intake influenced the alveolar bone, periodontal ligament, cementum, blood vessel count, and tooth displacement under orthodontic force. The extent of these changes was age dependent, with distinct effects observed in juvenile and adult mice. Juvenile mice analyzed in the latency phase of medication exhibited behaviors resembling those of adult mice.

Introduction: Oral appliance (OA) therapy is widely used as an alternative to continuous positive airway pressure (CPAP) therapy for treating obstructive sleep apnea (OSA). Traditionally, OA adherence has been assessed through subjective self-reports before, but the availability of objective adherence sensors now allows for more accurate monitoring. This study aimed to analyze one-year objective adherence data to identify adherence patterns over time and factors influencing adherence to OA therapy.

Materials and methods: Fifty-five OSA patients were recruited from a cohort study and underwent clinical follow-ups at baseline, 1, 6 and 12 months. Patients were treated with custom-made, titratable OAs, and adherence was objectively collected using embedded sensors. Adherence data were analyzed using both intention-to-treat (ITT) and per-protocol (PP) approaches. Statistical methods, including comparative analyses, logistic regression models, and multivariate linear regression were performed to identify predictors of adherence.

Results: Twenty-one patients dropped out before the 12-month follow-up, leaving 34 completed the entire study. At the 1-month follow-up, 80.0% of patients were classified as adherent, with a mean wearing time of 5.98 ± 2.38 hours per night. By 6 months, adherence decreased to 67.3%, with a mean wearing time of 5.69 ± 2.08 hours per night. Several significant predictors of adherence were identified, including larger baseline overjet, younger age, and marital status.

Conclusions: OA adherence declined significantly within the first 6 months but stabilized between 6 and 12 months. Key baseline factors, such as larger overjet, younger age, and being married or partnered are predictors of better adherence, while psychological Comorbidities are associated with lower adherence.

Background/objectives: In systematic reviews (SRs) with a meta-analysis, a subgroup analysis can be utilised to explore heterogeneity of treatment effects across patient characteristics and assess how patient characteristics, types of intervention, or trial characteristics modify the treatment effect. The aim of this meta-epidemiological study was to investigate the reporting and interpretation of subgroup analyses in the orthodontic literature.

Methodology: SRs published between 1st January 2017 - 30th June 2024 in five orthodontic journals and the Cochrane Database of Systematic Reviews (CDSR) were hand searched from journal websites. We assessed the presence of testing for subgroup differences (interaction test) and the interpretation and reporting of subgroup analysis limitations were also reviewed. Descriptive statistics of the SR characteristics and univariable cross-tabulation to detect associations between journal type and variables affecting interpretation of subgroup analyses were undertaken. On an exploratory basis, exact logistic regression was used to examine the effect of publication year on the correct interpretation of subgroup results.

Results: Five thousand one-hundred and one (5101) articles were screened, 298 SRs were identified of which 70 met the inclusion criteria. In the subgroup analysis, interpretation of the p-value was undertaken in just over half of cases (n = 40, 57.1%). Only 32.9% (n = 23) of subgroup analyses were deemed correctly interpretated. Most commonly, no subgroup limitations were reported by the authors (n = 48, 68.6%) even when such limitations existed. There was no association between year of publication and correct interpretation of subgroup analyses (OR:0.93, 95% CI: 0.70, 1.22, p = 0.62).

Conclusion: There appears to be a lack of awareness of how to correctly interpret subgroup analyses from forest plots. Only a third of orthodontic subgroup analyses assessed in this study were correctly interpreted. Misinterpretation of the effect of covariates (e.g. patient characteristics) on the effect of a treatment intervention could potentially have a negative impact on patient healthcare decisions. Recommendations to improve the interpretation of subgroup analyses are proposed.

Aim: To compare directly printed aligners (DPA) and thermoformed aligners (TFA), evaluating the potential release and dispersion of microplastic (MP) and nanoplastic (NP) particles under simulated oral conditions.

Materials and methods: DPA samples (Graphy Tera Harz TC-85-DAC resin) and TFA samples (Invisalign® SmartTrack) were subjected to rubs in an ultrapure water bath. The liquid was collected post-friction and analyzed for MPs and NPs using various techniques: optical microscopy (OM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). Also, plastic residues were quantified by weighing after drying within a laminar flow hood. Microscopic image analyses comprised the quantification of the average size of MPs and NPs, their concentration by TEM, and the roughness analysis by AFM.

Results: The masses of MPs and NPs separated after rubbing were 0.001 g/200 µl and 0.004 g/200 µl for TFA and DPA samples, respectively. TEM analysis confirmed that DPA samples had larger (203.08 ± 2651.65 μm²) and more numerous particles compared to TFA (0.23 ± 27.53 μm²), even though it was not possible to distinguish the MPs and NPs due to clustering of the plastic residuals. AFM analysis indicated a bigger root mean square grain size for TFA than DPA; similarly, the mean roughness was lesser in the DPA sample than TFA one.

Conclusions: DPA generated larger and more numerous plastic particles compared to TFA, though grain-size characterization was challenging due to particle aggregation. This suggests that the manufacturing process and materials used in DPA could impact the creation of MPs and NPs during simulated mastication, highlighting a potential area for process optimization.