The Angle orthodontist最新文献

Objectives: To compare the bracket positioning accuracy of a traditional and an artificial intelligence (AI)-assisted digital indirect bonding (IDB) method to explore the current usefulness of AI for optimizing orthodontic bracket positioning.

Materials and methods: Twenty-five clinicians positioned brackets using traditional and AI-assisted digital IDB methods. Bracket positioning differences were quantified using digital superimposition of bracket setups and compared with an optimal setup. A total of 1800 bracket positioning differences were evaluated. One-tailed t-tests were used to determine whether these differences were within limits of 0.5 mm in mesial-distal and occlusal-gingival dimensions and within 2° for tip.

Results: Overall mean bracket position differences between the traditional and digital setups were 0.28 mm for mesial-distal placement and 0.32 mm for occlusal-gingival placement; both were significantly below the 0.5-mm limit. In contrast, differences in tip were 3.4°, which was significantly greater than the 2° limit. Comparisons with an optimal setup showed overall statistically significant differences in mean bracket positioning for tip but not for the mesial-distal or occlusal-gingival measurements for both the traditional and AI-assisted digital IDB methods. However, the digital method was more accurate for bracket tip.

Conclusions: Bracket positioning is consistent and highly accurate in linear dimensions with both traditional and digital IDB methods; however, AI may be useful for improving accuracy of bracket angulation. Clinicians who currently use traditional IDB methods may adopt AI-assisted digital IDB without compromising bracket positioning accuracy.

[This corrects the article DOI: 10.2319/012007-29.1.].

Objectives: To evaluate, from the perspective of patients, the influence of social media (SM) on the choice of orthodontist and the acceptance of orthodontic treatment (OT) proposed by a professional.

Materials and methods: This cross-sectional study was conducted using an online questionnaire that contained 17 items distributed across four sections. Individuals older than 18 years, who were treated or sought OT, and who had SM accounts were included. Data were collected via Google Forms using the snowball technique and subsequently analyzed using the Mann-Whitney U-test. Effect size (ES) was calculated (small, moderate, or large).

Results: Of the 206 participants, 148 were women (71.8%), and 58 were men (28.2%), with a mean age of 37.3 ± 15.0 years. The most used SM applications were WhatsApp (95.1%), Instagram (92.2%), YouTube (56.8%), and Facebook (30.1%). Women respondents 36 years old or younger who were single and had no higher education showed a significant difference in choosing a professional and accepting OT on all questionnaire items (P < 0.001). Among SM platforms, Instagram was the one used most often to choose a professional and OT modality as well as considered important for revealing the professional's academic training. By contrast, WhatsApp was the least used for before-and-after posts, while YouTube was seldom used to evaluate posted comments. For variables with significant differences, the ES ranged from moderate to large.

Conclusions: SM, especially Instagram, can influence decision-making when choosing an orthodontist and accepting the recommendations for OT proposed by a professional.

Objectives: The aim of this study was to evaluate the effect of aging and mechanical brushing on the color stability and translucency of three-dimensionally (3D) printed and thermoformed transparent aligners (clear aligners [CAs]) of different thicknesses.

Materials and methods: Three types of CAs (Dentsply Sirona Essix [Group 1], Scheu-Dental Thermoforming Foils [Group 2], and 3D-printed Nexdent [Group 3]) in two thicknesses (0.75 mm and 1.0 mm) were used. Each group was divided into cleaned and noncleaned subgroups (n = 10). Samples were aged in artificial saliva and subjected to mechanical brushing. Color differences (ΔE00) and relative translucency parameter values (RTP00) were recorded at 1-week intervals over 4 weeks. Statistical analyses included generalized linear models and repeated measures analyses of variance (ANOVAs) for normally distributed parameters, and robust ANOVAs and Friedman tests for nonnormally distributed parameters (P < .05).

Results: Group 1 had the highest mean RTP00 values, while Group 3 had the lowest mean RTP00 values. Noncleaned CAs exhibited higher RTP00 values than cleaned CAs (P < .05). RTP00 values decreased significantly over time, with Group 3 showing notable differences between cleaned and noncleaned subgroups. Thinner materials (0.75 mm) displayed greater color changes than thicker ones (1 mm).

Conclusions: 3D-printed CAs demonstrated more significant color variation and less translucency in comparison to thermoformed CAs. Regular cleaning helps maintain translucency and color stability, but the choice of aligner material is crucial.

Objectives: To examine the relation of maxillary permanent central incisor rotation with the primary palatal margin (PPM) and overjet in the mixed dentition in complete unilateral cleft lip and palate (cUCLP).

Materials and methods: Dental casts and preorthodontic records taken before alveolar bone grafting were examined to exclude patients having permanent teeth distal to the cleft side maxillary central incisor (CS1) and mesial to the cleft. Maxillary central incisor rotation, the angle between PPM and midline, proximity of the lingual surface of the central incisor to PPM, and overjet were measured from standardized occlusal photographs of the dental casts of 54 children with repaired cUCLP (38 M, 16 F; aged 8.7 ± 1.0 years). Descriptive analysis and correlation statistics were performed.

Results: Rotations were noted in 92.6% of the CS1. Their magnitude (111.2 ± 24.2°) was significantly greater than the noncleft side maxillary central incisor (NCS1) rotations (76.7 ± 15.7°). Rotations were predominantly distolabial for the CS1 and distopalatal for the NCS1. The PPM was located within 2 mm of the lingual surface of the CS1 in 35.2% of the sample. Severe CS1 rotation existed in 48.2% of the sample and was significantly correlated with the PPM angle (r = 0.3; P = .046) and when its proximity to the PPM was within 2 mm (φ = 0.3; P = .028). Overjet was not significantly correlated with the magnitude of rotation.

Conclusions: The angle between PPM and the midline and its proximity to CS1 are associated with the severity of CS1 rotation in repaired cUCLP. Orthodontic implications are discussed.

Objectives: To evaluate the effectiveness and accuracy of clear aligners (CA) in maxillary molar distalization and rotation for nonextraction Class II correction in the permanent dentition.

Materials and methods: This systematic review of the literature (2015-2024) followed PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. Studies included orthodontic patients in the permanent dentition with dental Class II, mild or no skeletal discrepancies, 2-6 mm crowding, treated with CA without extractions (except maxillary third molars) or adjunctive therapies beyond Class II elastics. Data focused on maxillary molar distalization, rotation, accuracy, and complications. Risk of bias was assessed using ROBIN-I, with evidence level graded per the SBU protocol.

Results: Sixteen studies were categorized into Group A (initial aligner or distalization outcomes) and Group B (including refinements). Group B reported greater accuracy and distalization due to sequential distalization protocols, Class II elastics, and refinements. After refinements, CA achieved 1.84-2.98 mm of maxillary molar distalization with 85% maximum accuracy. First-molar rotation reached 8.09°, with 78.4% maximum accuracy. No significant vertical skeletal changes were observed. Challenges included anterior anchorage loss, buccolingual tipping of upper molars, and patient compliance monitoring. Methodological variability and participant demographics prevented a meta-analysis.

Conclusions: CA effectively achieves maxillary molar distalization and rotation in nonextraction Class II patients. Sequential distalization protocols and refinements improve treatment outcomes, whereas early incorporation of Class II elastics, combined molar movements, and compliance monitoring may enhance treatment efficiency.

Objective: To evaluate how high-frequency vibration (125 Hz) combined with light or optimal orthodontic forces affects osteoclast numbers and root volume during tooth movement in Wistar rats.

Materials and methods: Using a split-mouth design, 96 sites in male Wistar rats were randomly assigned to six groups: control, high-frequency vibration (HFV), light force (LF, 5g), light force with vibration (LF/HFV), optimal force (OF, 10g), and optimal force with vibration (OF/HFV). First maxillary molars were moved mesially using nickel-titanium (NiTi) closed coil springs. Root volume and osteoclast numbers were measured using Micro-CT and histomorphometry at Days 1, 7, 14, and 21.

Results: After 21 days, osteoclast numbers increased significantly in HFV (5.25 ± 0.48, P =. 002), LF/HFV (10.00 ± 0.41, P < .0001), OF (13.75 ± 0.48, P <.0001), and OF/HFV (15.25 ± 0.85, P < .0001) groups. Root volume decreased significantly in LF/HFV (7.75 ± 0.18 mm3), OF (6.68 ± 0.24 mm3), and OF/HFV (6.28 ± 0.14 mm3) groups compared to control (all P < .0001). HFV alone increased osteoclast numbers but did not affect root volume. The OF/HFV group showed the highest osteoclast numbers and root volume reduction. Three-way analysis of variance revealed that time, vibration, and force significantly reduced root volume (P < .0001). Notably, the interaction effects on osteoclast numbers were significant in LF group (P < .0001), but not OF group (P = .338).

Conclusions: Combined high-frequency vibration and orthodontic forces increased osteoclast numbers and root resorption. Light forces with high-frequency vibration promoted osteoclast formation while minimizing root resorption compared to optimal forces. Additionally, the duration of this combined treatment significantly affected the extent of root resorption.

Objectives: To evaluate and compare dentoalveolar changes after orthopedic treatment of growing skeletal Class II patients using either pushing or pulling force mechanics anchored to bimaxillary miniplates in comparison with deferred treatment control subjects.

Materials and methods: A total of 39 patients (24 male, 15 female; mean age 11.59 ± 0.56 years) was equally and randomly allocated to one of three study groups: pushing group (A), pulling group (B), and control group (C). Dental changes were assessed using pretreatment (T1) and posttreatment (T2) cone-beam computed tomography scans.

Results: One patient dropped out; therefore, 13, 12, and 13 patients were analyzed in groups A, B, and C, respectively. In groups A and B, overjet decreased by 7.00 ± 1.35 mm and 8.17 ± 1.4 mm, respectively. No significant change was observed in axial inclination of the mandibular incisors in either of the intervention groups between T1 and T2. Axial inclination of the maxillary incisors decreased significantly in Group B by 3.75 ± 1.71°. The sagittal position of the mandibular first molar changed significantly in Group A (4.15 ± 1.28 mm) and Group B (4.00 ± 1.41 mm). Maxillomandibular basal arch width differences were greater than -0.39 ± 1.87 mm in all study groups. No significant transverse arch measurement changes were observed.

Conclusions: The use of either pushing or pulling force mechanics using bimaxillary skeletal anchorage was effective in improving Class II dental relationships without dentoalveolar side effects. Pretreatment transverse discrepancy should be assessed to incorporate maxillary expansion into the treatment protocol for patients diagnosed with maxillary arch constriction.

Objectives: To assess three-dimensional (3D) changes in tooth position, arch dimensions, and gingival levels after mandibular total arch distalization in skeletal Class III malocclusion.

Materials and methods: Skeletal Class III patients treated with mandibular total arch distalization using interradicular temporary anchorage devices were analyzed using stepwise 3D superimposition and reorientation of serial cone beam computed tomography (CBCT) and digital casts (N = 19). After mandibular regional superimposition of pre- (T0) and post-treatment (T1) CBCTs, the mandibles were segmented and merged with the corresponding digital casts, generating reoriented, superimposed T0 and T1 digital casts. Changes in individual tooth position, arch dimensions, occlusal plane, and clinical crown height (CCH) were measured.

Results: Mandibular teeth exhibited posterior movement ranging from 1.74 to 2.50 mm with significant lateral movement of the premolars and increase of inter-premolar width by 2.15-2.66 mm (P < .05). Extrusive movement of the entire dentition excluding the second molar was noted (P < .05), inducing changes of the occlusal plane. The overall changes in CCH were limited to -0.23 to 0.16 mm. CCH significantly increased in the premolars and decreased in the first molar (P < .05).

Conclusions: Based on a stepwise digital superimposition, mandibular total arch distalization induced complex 3D changes in the mandibular arch, including distalization, extrusion, and increase of interpremolar width. Gingival margins generally were maintained, though mild-to-moderate recession was suggested in around 20% of the premolars, which may require attention.