Journal of Orthodontics最新文献

Objective: To explore early treatment practices and perceptions among members of the American Association of Orthodontists (AAO).

Design: Cross-sectional survey.

Participants: Members of the AAO.

Methods: An electronic questionnaire was pre-piloted and circulated via email to members of the AAO. The survey questions covered respondent demographics, clinical experience, preferred timing of intervention, treatment approaches and clinicians' perceptions with regard to early interceptive treatment. Descriptive statistics were performed.

Results: A total of 228 responses were obtained (response rate = 5.12%). Treatment was commonly timed using dental age (61%) and pubertal signs (61.8%). Several problems were treated in the mid-mixed dentition phase (8-9 years) including posterior crossbite (51.3%) increased overjet (41.7%), crowding (39.5%), space loss (41.23%) and anterior open bite (37.3%). Commonly reported treatment approaches included the use of sectional fixed appliances for treatment of anterior crossbite (81.6%), rapid palatal expander for treatment of posterior crossbite (63.6%) and anterior bite plane for deep overbite correction (62.7%). Herbst appliance (42.1%) and facemask (89%) were commonly prescribed for early correction of Class II and III, respectively. Lingual and palatal arches were commonly used to preserve arch length. The majority of respondents (60.1%) were proponents of two-phase orthodontic treatment.

Conclusions: Early orthodontic treatment in the mid-mixed dentition stage was widely advocated for orthodontic intervention. Various malocclusions, including posterior and anterior crossbite, increased overjet, crowding, space loss and anterior open bite, were reported to be commonly addressed during this phase. Popular treatment approaches included sectional fixed appliances, Herbst appliance, facemask, rapid palatal expanders and anterior bite planes.

Objective: To investigate young people's experience of retainer wear in the immediate term and at 6 months after appliance removal, and to explore the factors affecting retainer wear adherence.

Design: Qualitative study.

Setting: Orthodontic departments at two teaching hospitals in Yorkshire, UK.

Participants: A total of 12 participants aged 13-18 years were recruited using a purposive sampling approach.

Methods: Data collection occurred through one-to-one, virtual, photo-elicitation interviews at two time points (immediate and 6 months) with data analysed using interpretative phenomenological analysis (IPA).

Results: Three overarching themes were developed to describe young people's experience of orthodontic retention: immediate experience and expectation of retainers; the process of adaptation; and motivating factors. Barriers to adherence were mostly ascribed to daytime wear, despite normalisation of retainers in young people's lives. Interventions to help individuals overcome the initial adaptation phase and self-manage their foreseen problems of forgetfulness include routines and reminders, which seem to be less important at 6 months. At both time points, internal and external motivation significantly contribute to retainer adherence, with compensatory changes in behaviour being more important at 6 months.

Conclusions: Understanding early experiences of retainer wear can help clinicians to provide timely and well-targeted interventions and information. Co-constructing unique adherence strategies may help to overcome the initial adaptation phase, with particular emphasis on understanding the individual.

Objective: To evaluate the effect of 10% papain as an enamel deproteinising agent on the shear bond strength (SBS) of three orthodontic adhesives: Transbond XT, resin-modified glass ionomer cement (RMGIC) and Biofix.

Design: Single-centre, double-blinded, split-mouth randomised controlled trial.

Setting: Department of Orthodontics and Dentofacial Orthopaedics, Nair Hospital Dental College, Mumbai, India.

Participants: A total of 20 participants, requiring bilateral premolar extraction for fixed orthodontic treatment in both the maxillary and mandibular arches, were included in this study.

Methods: In total, 80 premolars from the above-mentioned participants were divided into four groups as follows: group A: Transbond XT deproteinised with 10% papain gel; group B: Biofix deproteinised with 10% papain gel; group C: RMGIC deproteinised with 10% papain gel; and group D: Transbond XT without enamel deproteinisation as a control group-bonded as instructed by the manufacturer. After deproteinisation, brackets were bonded and after a follow-up period of 28 days, the teeth were extracted. The SBS was then measured using the Universal Testing Machine. The force needed to shear the bracket was documented, and bond strengths were subsequently calculated in megapascals (MPa). The obtained results were subjected to statistical analysis and one-way ANOVA was performed to compare the mean SBS between the groups. Subsequently, pairwise comparisons were conducted using Tukey's post hoc test.

Results: There was a statistically significant difference in SBS among all groups (P = 0.002). The SBS of TransXT with deproteinisation increased significantly compared with TransXT without deproteinisation (P = 0.03). There was no statistically significant difference between the SBS of TransXT without deproteinisation and RMGIC (P = 0.47) and Biofix (P = 0.39), both with deproteinisation.

Conclusion: The use of 10% papain for deproteinising enamel improved the SBS of all materials. Deproteinising improved the SBS of RMGIC and Biofix to the level of TransXT without deproteinisation.

Introduction: Temporomandibular joint (TMJ) ankylosis is a debilitating condition characterised by the fusion of bony or fibrous tissues in the TMJ, resulting in restricted mouth opening, functional challenges and facial deformities. This report highlights the complexity and multifaceted nature of TMJ ankylosis and emphasises the significance of early intervention and a multidisciplinary approach. Distraction osteogenesis has emerged as a successful method for managing TMJ ankylosis and associated facial asymmetry. Post-distraction orthodontic management is essential to address occlusal changes, including posterior open bite and crossbite.Diagnosis and treatment plan:A 17-year-old boy with unilateral right-sided TMJ ankylosis presented with restricted mouth opening, facial asymmetry and functional difficulties. Multidisciplinary treatment planning involved distraction osteogenesis, condylectomy, coronoidectomy and orthodontic correction to improve the occlusion and facial aesthetics.

Results: The treatment significantly improved facial aesthetics, mouth opening, occlusion and the patient's confidence and self-esteem.

Conclusion: This case report underscores the complexity of TMJ ankylosis and the need for a comprehensive approach, including surgical and orthodontic interventions. Collaboration among healthcare professionals and ongoing research is vital to refine treatment approaches and improve the quality of life for patients with TMJ ankylosis.

Background: New technologies have paved the way for newer fabrication techniques, such as rapid prototyping, which has gained popularity in the fabrication of several orthodontic appliances including retainers.

Aim: To evaluate the stability, survival time and periodontal health associated with vacuum-formed retainers (VFRs), bonded retainers (BRs) and rapid prototype retainers (RPRs) over a period of 12 months in retention.

Study design: Prospective clinical study.

Methods: A total of 72 participants completing fixed orthodontic treatment were allocated to the following three groups by the investigators based upon their initial malocclusion, compliance and preferences: VFR; BR; and RPR. The primary outcome was Little's Irregularity Index (LII). Other stability parameters, including arch length (AL), inter-canine width (ICW) and inter-molar width (IMW), were also assessed immediately after debonding (T0) and 12 months (T2) after debonding. In addition, survival time, calculus index and gingival index (GI) were assessed.

Results: LII showed a significant difference (P = 0.00) between the groups and was increased in the VFR group (0.18 ± 0.22 mm) compared to the BR (0.03 ± 0.05 mm) and RPR (0.01 ± 0.03 mm) groups but was not clinically significant. The mean survival time of maxillary retainers was longest for the RPR group (220.63 days; 95% confidence interval [CI] = 194.1-247.16) but there was no significant difference between the three groups (P = 0.43). The mean survival time of mandibular retainers was higher and the same for the VFR and RPR groups (240 days; 95% CI = 240-240) and there was no significant difference between the three groups (P = 0.38). The calculus index score (P = 0.00) was statistically significant between the groups, with an increased score for the BR group (0.33 ± 0.27) compared to the VFR (0.07 ± 0.16) and RPR (0.13 ± 0.22) groups. Similarly, the GI score (P = 0.02) was statistically significant between the groups and was increased in the BR group (0.01 ± 0.19) compared to the VFR (-0.15 ± 0.18) and RPR (-0.06 ± 0.15) groups. The increase in calculus index and GI scores for the BR group were not clinically significant.

Conclusion: There were no clinically significant differences between the three retainer groups in terms of stability, periodontal health and time to failure.

Objective: To compare the space closure, root resorption and canine angulation during en-masse retraction of the labial segment after extraction of first premolars with or without interseptal bone reduction distal to the maxillary canines.

Design: A single-centre, parallel randomised control trial included 16 participants with a mean age of 21.5 years. Participants were allocated into treatment groups using blocked randomisation, and blinding was employed for outcome assessors and data analysts.

Interventions: The control group consisted of eight participants who underwent extraction of maxillary first premolars only, while the experimental group included eight participants who underwent interseptal bone reduction immediately after premolar extraction. En-masse retraction was performed using conventional friction mechanics with anchorage reinforcement in both groups.

Outcomes: Measurements of space closure were conducted over 3 consecutive months during retraction. The time taken for total space closure was recorded. Cone-beam computed tomography scans were taken before and 3 months after retraction to assess root resorption and canine angulation.

Results: The experimental group demonstrated a significant increase in the rate of en-masse retraction compared to the control group over 3 months (mean difference [MD] = 1.09 mm, 95% confidence interval [CI] = 0.78-1.40), with an overall space closure rate of MD 0.26 mm/month (95% CI = 0.17-0.34). However, these changes were of minimal clinical significance. The change in canine angulation (MD = 4.50°, 95% CI = -1.61-10.61) did not exhibit statistical significance. Substantial root resorption was observed in six maxillary anterior teeth, with no difference between the groups.

Conclusion: Interseptal bone reduction is a minimally invasive surgical technique, resulting in an accelerated rate of en-masse retraction in the experimental group over 3 months. However, despite the statistical significance, the clinical impact on overall space closure was minimal, with a difference of only 0.26 mm/month observed between the groups. Interseptal bone reduction did not affect the change in canine angulation and root resorption.

Objective: To investigate the accuracy of full arch scans taken using the iTero Element 2^® under clinical settings.

Design: Prospective clinical study.

Methods: A customised upper removable appliance (URA) with four spheres (A-D) was fabricated from a maxillary arch iTero^® scan for a 24-year-old patient. Six linear values were measured on the URA using a high-accuracy coordinate measuring machine. A total of 60 intra-oral iTero^® scans were taken by two operators (HA and AS) with the test URA inserted to the participant's maxillary dentition at T1 and T2. Geomagic Control X software was used to measure the six linear distances between the reference spheres (1-4) in all scans. Comparisons between distances on full arch scans to true distances on the URA were made to evaluate accuracy.

Results: The median distance to the prepared bench top URA mean was significantly away from zero for each operator and timepoint across all measurements except AD versus 14 and BD versus 24. Statistically significant, although clinically non-significant, differences in median linear distances in relation to the prepared benchtop URA were observed between evaluators in segments AB versus 12 (operator 1 -0.021 mm vs. operator 2 -0.06 mm) and AC vs. 13 (operator 1 -0.044 mm vs. operator 2 -0.167 mm) at T1.

Conclusion: The accuracy of scanners is defined as the trueness and precision of the captured scans to the dental arches. The accuracy of iTero Element 2^® is acceptable for diagnosis and treatment planning in orthodontics. Length and location of the scanned segment and scanning sequence 'protocol' affect accuracy.