The Angle orthodontist最新文献

The incidence of maxillary canine impaction is estimated at approximately 1.7% of the population and is multifactorial in etiology. Several case reports suggest a potential relationship between canine impaction and root dilaceration of the adjacent premolar, indicating mechanical interference due to their proximity. In such cases, when avoiding tooth extractions is desired, it is crucial to consider specific clinical approaches to prevent contact with the dilacerated root during traction. This case report describes traction of an impacted maxillary canine in a female patient resulting from severe palatal root dilaceration of the adjacent first premolar. The canine was surgically exposed and traction was initiated after endodontic therapy and root sectioning of the affected premolar. After 24 months of orthodontic treatment, the results were satisfactory, with adequate gingival contour, 2 mm overjet and overbite, and a Class I relationship of canines and molars. No apparent root resorption was observed, and bone structure was preserved. A multidisciplinary approach is fundamental for the success of treatment in such cases, enabling achievement of a functionally and esthetically stable occlusion while avoiding tooth extractions.

Objectives: To compare the effect of three different maxillary retainers: round multi-strand stainless steel (SS), rectangular white gold-plated SS, and vacuum-formed (VF) retainers on treatment stability, retainer integrity, and gingival health over 12 months.

Materials and methods: Seventy subjects who finished fixed orthodontic treatment and required orthodontic retainers in the upper arch were randomly divided into three groups. The first group (mean age: 21.0 years) received bonded three multi-strand round (0.0175-inch) SS retainer, the second group (mean age: 20.4 years) received bonded rectangular (0.038 × 0.016-inch) white gold-plated SS retainer, the third group (mean age: 20.0 years) received removable VF retainer. Bonded retainers were extended from lateral to lateral incisor while VF retainer was extended to the most distal molar. After 1 year, all subjects were recalled. The primary outcome was to assess relapse in upper labial segment alignment. The secondary outcome was to evaluate the plaque index (PI) and gingival index (GI) of the upper labial segment teeth and retainer failure rate.

Results: There was no statistical difference in the average irregularity index (IRI), PI, and GI among the three groups (P = .667, P = .781, P = .487, respectively). Retainer failure rate was significantly higher in Group III (60.9%) compared to Group I (20.8%) and Group II (34.8%, P = .017).

Conclusions: After 1 year, anterior tooth alignment stability and gingival health parameters were not different between bonded and VF retainers. However, the VF retainer exhibited a higher failure rate compared to bonded retainers.

Objectives: To investigate the effects of buccal osteotomy angulation on surgically assisted rapid palatal expansion (SARPE) patterns.

Materials and methods: A finite element analysis (FEA) model of the maxilla with Haas expander was constructed from a cone beam computed tomography (CBCT) image using Mimics, Geomagic, and solidWorks software. One-mm-thick buccal osteotomies were created with different combinations of 0°, 10°, 20°, and 30° from the horizontal plane to simulate differences in bilateral osteotomy angulation. Springs were placed at the buccal osteotomy gaps to mimic the strain of the bone callus. After applying 150 Newton of expansion force at the level of the expander jackscrew in each FEA scenario, the expansion pattern of the hemimaxillae was evaluated in Ansys software.

Results: Scenarios with 20° (0-20°; 10-30°) and 30° (0-30°) differences resulted in significant transverse asymmetric expansion. Among the groups with 10° difference, 0-10° resulted in relatively parallel expansion, while 10-20° and 20-30° experienced V-shaped expansion with more anterior widening.

Conclusions: A larger difference between the angulations of the left and right buccal osteotomies resulted in increased asymmetry in both the transverse and vertical dimensions after expansion.

Objectives: Evaluate the changes in oral microbiota linked to orthodontic treatment by analyzing the 16S rRNA gene.

Materials and methods: A total of 22 articles was included in the systematic review. The methodological quality of these studies was assessed using the Newcastle-Ottawa Scale for nonrandomized studies and the Risk of Bias tool for randomized studies.

Results: Orthodontic appliances significantly influenced the composition of oral microbiota. Specifically, fixed orthodontic appliances were linked to an increase in periodontopathogenic bacteria associated with various systemic diseases. In contrast, transparent aligners correlated with an increase in Streptococcus species.

Conclusions: In this study, we evaluated the changes in oral microbiota associated with orthodontic treatment by analyzing the 16S rRNA gene. Results revealed significant alterations in oral microbiota following orthodontic treatment; however, significant variability among studies prevents firm conclusions. Additional research is essential to clarify the effects on oral health.

Objectives: To compare the efficacy of clear aligners and Z-spring (ZS) appliances in treating dental anterior crossbite (AC) during the mixed dentition period.

Materials and methods: Thirty patients (7-12 years) with Angle Class I occlusion and isolated pseudo-Class III AC were randomly assigned to clear aligners (Group A, n = 15) or ZS appliances (Group B, n = 15). Outcomes were evaluated based on duration, cephalometric changes, model analysis, and oral health-related quality of life (OHRQoL), assessed using the Child Oral Health Impact Profile-Short Form-19 (COHIP-SF-19).

Results: AC was successfully corrected in all patients. Treatment duration was significantly shorter in Group B (48.4 ± 27 days) than in Group A (96.3 ± 22.7 days) (P < .05). U1-NA angle increased by 5.9° and overjet by 4 mm in Group A; in Group B, U1-NA increased by 7.7° and overjet by 4.2 mm (P < .01). Intergroup cephalometric changes (ΔT1-T0) were not significant (P > .05). In Group A, incisal and gingival arch depths increased significantly (2.6 mm and 1.17 mm, respectively; P < .001), whereas no significant changes occurred in Group B (P > .05). COHIP-SF-19 scores were comparable (P > .05).

Conclusion: Clear aligners and ZS appliances were effective in treating dental AC, achieving normal overjet relationships. However, ZS appliances may cause greater tipping, whereas clear aligners facilitate tipping, alignment, and bodily movement. Treatments demonstrated comparable effects on OHRQoL of children. This study provides a foundation for future research on different appliances for managing AC in the mixed dentition.

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.