To quantitatively compare nickel and chromium ion release and corrosion resistance of copper–nickel–titanium (Cu–NiTi), stainless steel (SS), and beta-titanium (β-Ti) archwires following immersion in povidone-iodine (Betadine), chlorhexidine, amine fluoride (Amflor) mouthwashes, and distilled water. An in vitro study was performed using 60 rectangular archwire specimens (20 each of Cu–NiTi, SS, and β‑Ti), divided into four subgroups according to the immersion medium (chlorhexidine, Betadine, Amflor, distilled water; n = 5 per subgroup). Wires were immersed in each solution at 37 °C for 1.5 h to simulate approximately 3 months of daily mouthwash exposure. Metal ion release was analyzed by atomic absorption spectrophotometer (AAS), while corrosion behavior was assessed using potentiodynamic polarization via a Zive SP1 potentiostat. Two-way analysis of variance (ANOVA) with Tukey’s post hoc test was used to determine statistically significant effects of wire and solution type (p < 0.05). Significant differences were observed among wire and solution types (p < 0.001). β‑Ti wires showed no detectable metal ion release and the lowest corrosion rates. Cu–NiTi and SS wires exhibited measurable nickel release, highest in chlorhexidine (46.91 ppm for Cu–NiTi, 42.93 ppm for SS). Chromium release was exclusive to SS (maximum 23.62 ppm). The corrosion hierarchy was chlorhexidine > Betadine > Amflor > distilled water, with β‑Ti demonstrating superior resistance. Both material composition and mouthwash formulation critically affect corrosion and ion release. β‑Ti exhibits optimal biocompatibility, whereas chlorhexidine significantly accelerates corrosion.
To compare the acceleration effect of piezocision and modified piezocision (a combination of piezocision and piezopuncture) on canine retraction. In this two-arm parallel, split-mouth randomized clinical trial, 30 participants (15–25 years) undergoing fixed orthodontic treatment with the extraction of first upper premolars and canine retraction were randomly assigned to piezocision or modified piezocision groups. Thirty surgical procedures were performed using a split-mouth design, with 15 in each interventional arm, and the contralateral sides were treated in a conventional way (control). Outcomes assessed included the amount of canine retraction (primary outcome variable), rotation, inclination changes, root resorption, and molar anchorage loss. Data analysis included paired t‑tests, Wilcoxon signed-rank tests (between experimental and control sides), independent t‑tests, and Mann–Whitney U tests (between experimental sides). The level of significance was set at P < 0.05. Canine retraction on the experimental side in the piezocision group was 1.5 times greater than on the control side (3.83 ± 0.17 mm vs. 2.46 ± 0.31 mm, P < 0.001). In the modified piezocision group, retraction was nearly twice as great on the experimental side compared to the control (5.13 ± 0.14 mm vs. 2.50 ± 0.32 mm, p = 0.001). The modified piezocision technique showed significantly higher (p-value < 0.001) canine retraction than the original piezocision technique. Secondary outcomes showed nonsignificant differences. No harm was observed other than mild postsurgical pain and swelling, which were controlled with appropriate medications. Both modified and traditional piezocision techniques effectively accelerated canine retraction. However, the modified technique demonstrated superior results, offering a promising avenue for future orthodontic practice.
Artificial intelligence (AI) is rapidly transforming orthodontics, yet a comprehensive and up-to-date bibliometric analysis is lacking. This study systematically maps key research areas, influential contributors, and collaborative networks driving AI innovation. A comprehensive search was conducted in the Web of Science (Clarivate, London, UK) for AI and orthodontics articles up to January 10, 2026. CiteSpace (version 6.2.R6, Drexel University, Philadelphia, PA, USA) and VOSviewer (version 1.6.20, Centre for Science and Technology Studies, Leiden University, Leiden, The Netherlands) were used to extract and visualize the data, including publications, journals, institutions, countries, highly cited articles, authors, and keywords. A total of 454 articles were included, authored by 2150 authors affiliated with 674 institutions across 64 countries. The research landscape has expanded exponentially since 2019, with the USA, China, and South Korea emerging as primary global collaboration hubs. Keyword burst analysis highlighted the rapid clinical integration of AI applications in image recognition, diagnosis, and evaluation. This study maps AI integration trends, showing how AI enhances diagnostic precision and treatment evaluation. These insights might be able to guide researchers toward cutting-edge frontiers. Future research should prioritize multimodal data integration, personalized treatment workflows, and patient privacy protection.
To investigate how age-related changes in midpalatal suture morphology influence skeletal response to varying force magnitudes in nonsurgical rapid palatal expansion (RPE) using a rat model. Nine rats were allocated to an age-based analysis (2, 4, and 8 months; n = 3 per group) to evaluate physiologic age-related development in midpalatal suture morphology. Thirty-five mature rats (8 months) were further assigned to light force (50 g), heavy force (200 g), or control groups. Forces were applied via custom-fabricated expansion devices for 3, 7, and 14 days. Micro-computed tomography (micro-CT), histological analysis, and immunohistochemistry were performed. Histological analysis included qualitative and quantitative assessments. Micro-CT was used for evaluating suture separation, bone volume fraction (BV/TV), and bone mineral density (BMD). Immunohistochemistry assessed the expression of bone remodeling markers. Increased age correlated with reduced midpalatal suture separation and bone formation. Heavy forces resulted in significantly greater suture separation at early time points but also induced more bone resorption, as indicated by lower BV/TV and BMD values. Immunohistochemistry confirmed increased RANKL expression in heavy force groups, indicating enhanced bone remodeling activity. Midpalatal suture response is significantly influenced by both age and the magnitude of applied force. While heavy force promotes faster suture separation, it leads to increased bone resorption and reduced bone quality. In contrast, light force results in a more gradual separation but supports earlier osteoclastic activity, greater vascularization, and better preservation of bone structure. These findings underscore the importance of age-appropriate force selection in nonsurgical RPE protocols.
To examine associations between vertical craniofacial growth pattern, self-reported daytime sleepiness, sleep-related complaints, and lip posture in adolescents. This cross-sectional study included 157 adolescents aged 12–14 years classified as hyperdivergent (n = 121) or normodivergent (n = 36). Daytime sleepiness and sleep-related complaints were assessed using an Epworth sleepiness scale (ESS)-based questionnaire and Berlin questionnaire (BQ)-derived items. Lip posture was measured cephalometrically. Independent t‑tests, chi-square/Fisher exact tests, Pearson correlations, and multiple linear regression were used. Hyperdivergent adolescents had higher ESS and BQ scores (p < 0.001; ESS d = 0.70), more frequent sleep-disordered breathing (SDB)-related symptoms (p < 0.05), and a significant Frankfort mandibular plane angle (FMA)–ESS association after adjustment for age, body mass index, and sex (β =0.354, p < 0.001). Lip posture showed no group differences or associations with BQ, with only weak correlations with ESS or sleep duration. Hyperdivergence, but not lip posture, was associated with greater questionnaire-derived sleepiness and SDB symptoms.
