Journal of Orthodontic Science最新文献

{"title":"Canine conundrum: Deciphering the factors at play - A systematic review.","authors":"Dishant Mahajan, Ajit V Parihar, Sharvari Mairal, Arya K Das, Akansha Pandey, Sarita Parihar","doi":"10.4103/jos.jos_94_24","DOIUrl":"https://doi.org/10.4103/jos.jos_94_24","url":null,"abstract":"<p><p>The objectives of this systematic review are to identify the factors influencing the treatment duration to resolve impacted maxillary canines and to evaluate the time duration to resolve maxillary impacted canines considering these factors. A comprehensive electronic database search was conducted within a limited time period (from 01/01/2001 to 31/12/2023). The literature was sought and collected through PubMed, LILACS, Web of Science, Scopus, and EBSCO. The protocol was registered as CRD42024476064 in the PROSPERO database (http://www.crd.york.ac.uk/PROSPERO). The selection criteria were based on PI(E)COS. The searches retrieved 678 unique citations. Titles and abstracts identified 264 full articles, from which 19 remained after the inclusion criteria were applied. Factors such as the patient's age, the position and angulation of the impacted canine relative to the midline and lateral incisor, the side of the impaction, and the technique used to address the impaction have a statistically significant impact on the treatment duration for impacted canines. However, the influence of the patient's sex on treatment duration remains inconclusive.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"14 ","pages":"13"},"PeriodicalIF":0.0,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12036762/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143997623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Debonding forces and failure modes of customized three-dimensional printed nano-ceramic hybrid resin fixed lingual retainers.","authors":"Noor S Alnuaimy, Akram F Alhuwaizi","doi":"10.4103/jos.jos_75_24","DOIUrl":"https://doi.org/10.4103/jos.jos_75_24","url":null,"abstract":"<p><strong>Background: </strong>Retention preserves the optimal esthetic and functional positions of teeth following the termination of active orthodontic treatment. Conventional stainless-steel multistrand fixed retainers have limitations and drawbacks, mainly related to retainer failure.</p><p><strong>Objectives: </strong>Nano-ceramic hybrid resin (SprintRay OnX) was employed to fabricate new, customized three-dimensional (3D)-printed lingual retainers, and their debonding forces and failure modes were evaluated.</p><p><strong>Materials and methods: </strong>Pairs of premolars were embedded in acrylic blocks. Fifty acrylic blocks were divided into five groups, including three different cross-sections of customized 3D-printed wires- round (1 mm), oval (1 × 1.5 mm), and semi-elliptical (1 × 1.5 mm)- and comparative stainless steel multistrand retainers (G and H and Respond). Retainers were bonded to the teeth using Transbond™ LR Light Cure Adhesive. The models were stored in distilled water for 24 hours, simulating the wet intraoral conditions. Debonding forces and failure modes were then evaluated. A vertical debonding force was applied to the interdental area of the bonded retainer. Post-retainer debonding failure mode was examined under a stereomicroscope (×10 magnification).</p><p><strong>Results: </strong>Semi-elliptical 3D-printed retainers yielded the highest debonding forces, followed by oval 3D-printed retainers, twisted G and H retainers, round 3D-printed retainers, and Respond retainers. The debonding forces of oval and semi-elliptical 3D-printed retainers did not differ significantly. The 3D-printed retainer groups presented predominantly cohesive failure due to the strong adhesion between the 3D-printed resin and adhesive.</p><p><strong>Conclusion: </strong>Oval and semi-elliptical 3D-printed retainers exhibited favorable debonding forces.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"14 ","pages":"2"},"PeriodicalIF":0.0,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12036752/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143987834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphology of maxillary and frontal sinuses in different skeletal vertical malocclusions.","authors":"Hafiz Zuhair Ahmed, Irfan Qamruddin, Hina Siddiqui, Sooraj Lohana, Sohail Khan, Sunia Soomar, Hunny, Afreen Panjwani","doi":"10.4103/jos.jos_215_23","DOIUrl":"https://doi.org/10.4103/jos.jos_215_23","url":null,"abstract":"<p><strong>Background: </strong>On every patient's lateral cephalogram, the frontal and maxillary sinuses are the most often seen paranasal sinuses. Impacted teeth alter the morphology of the frontal and maxillary sinuses. Consequently, it has an impact on the patient's look and occlusion.</p><p><strong>Objective: </strong>To determine the mean height, width, and index of maxillary and frontal sinuses and compare them among high, average, and low-angle patients underwent orthodontic treatment.</p><p><strong>Material and methods: </strong>A total of 192 cephalometric radiographs of patients who presented with malalignment of teeth having high, average, and low angles and underwent orthodontic treatment were selected. On radiograph, frontal sinus, maxillary sinus, and cephalometric landmarks were traced. Patients were divided into different classes of skeletal vertical malocclusion. The morphology of maxillary and frontal sinuses on lateral cephalogram was measured. Means ± SDs of the quantitative variable were calculated. ANOVA test was applied to compare maxillary and frontal sinus heights, widths, and indexes between high-angle, average-angle, and low-angle patients.</p><p><strong>Results: </strong>The mean ± SD of height, width, and index of frontal sinus was 30.41 ± 2.59, 10.81 ± 1.53, and 3.44 ± 0.68, respectively, while these findings for maxillary sinus were 40.09 ± 2.36, 36.33 ± 3.38, and 1.11 ± 0.07, respectively. The mean frontal sinus width was significantly different among profile angles (<i>P</i> < 0.001), while the mean maxillary sinus width, mean maxillary sinus width, and mean maxillary sinus index were significantly different among profile angles with <i>P</i> < 0.001.</p><p><strong>Conclusion: </strong>In comparison to high- and low-angle profiles, the frontal sinus width was greater in the average angle profile. The average width, breadth, and index in the maxillary sinus varied statistically between different angle profiles. In comparison to high- and low-angle profiles, the height, width, and index of the maxillary sinus were all higher in the average angle profile.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"14 ","pages":"5"},"PeriodicalIF":0.0,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12036757/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144064082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adult orthodontic consultations in private dental practice: How much information do patients remember when they leave the surgery?","authors":"Ausra Grybaite, Mohammed Awawdeh, Parmjit Singh","doi":"10.4103/jos.jos_86_23","DOIUrl":"https://doi.org/10.4103/jos.jos_86_23","url":null,"abstract":"<p><strong>Objective: </strong>With good communication and information retention being key aspects of valid consent, this study aimed to assess adult patient information recall immediately after an orthodontic consultation.</p><p><strong>Materials and methods: </strong>Adults interested in bracket-based or clear aligners were invited to take part at a single private dental practice. A 45-minute consultation with one of three general dental practitioners (GDPs) primarily providing orthodontics took place. A participant self-completed questionnaire tested recall of 20 items from the consultation. Demographics such as gender, age, level of English, education level, previous orthodontic experience and having a close family member or friend who had orthodontic treatment were also recorded.</p><p><strong>Results: </strong>Forty-two participants completed the questionnaire, and the information recall rate was 75% (mean score = 15). Three of the 42 participants recalled all 20 items. No statistically significant differences (<i>P</i> < 0.05) were found between information recall and any demographic variable, however, older participants (36 years and over) scored less (mean = 13.83) than participants 18-25 years (mean = 15.6).</p><p><strong>Conclusions: </strong>A quarter of information provided during an orthodontic consultation with a GDP in a private dental practice cannot be recalled immediately afterwards by patients and so it is recommended that any verbal or visual information is always supplemented with written information.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"13 ","pages":"48"},"PeriodicalIF":0.0,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11698248/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142932083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the association between orthodontic treatment and temporomandibular disorders in pediatric patient: A retrospective study.","authors":"Snigdha Pattanaik, Vishnu P Veeraraghavan, Arun K Dasari, Subhrajeet Narayan Sahoo, Kaladhar Reddy Aileni, Hema Suryawanshi, Santosh R Patil","doi":"10.4103/jos.jos_22_24","DOIUrl":"https://doi.org/10.4103/jos.jos_22_24","url":null,"abstract":"<p><strong>Objective: </strong>This retrospective study aimed to investigate the association between orthodontic treatment and development of temporomandibular disorders (TMDs) in pediatric patients.</p><p><strong>Methods: </strong>This study analyzed 122 pediatric patients (age 10-18 years) who underwent orthodontic treatment. The inclusion criteria included comprehensive orthodontic records and substantial clinical documentation, while the exclusion criteria targeted preexisting TMDs or syndromes affecting the temporomandibular joint. Demographic details, treatment characteristics, and radiographic analyses, including standardized cephalometric measurements, were recorded. Clinical records were systematically reviewed for signs and symptoms of TMD, with categorization based on TMD severity using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD).</p><p><strong>Results: </strong>Demographic characteristics revealed a mean age of 14.2 years, with a sex distribution of 36.9% males and 63.1% females. Pain, clicking/popping sounds, and limited jaw movement were reported by 23.0%, 16.4%, and 12.3% of the patients, respectively. TMD severity classification showed that 73.8% had no symptoms, 20.5% had mild symptoms, 4.1% had moderate symptoms, and 1.6% had severe symptoms. Statistical analyses revealed a significant association between TMD symptoms and sex (<i>P</i> = 0.023). Correlations among TMD severity, treatment duration (<i>P</i> = 0.036), and cephalometric changes were observed. Radiographic findings showed a moderate correlation with the gonial angle (r = 0.42) and a strong correlation with the condylar position (r = 0.58).</p><p><strong>Conclusion: </strong>This study provides insights into the complex relationship between orthodontic treatment and TMD development in pediatric patients. These findings suggest potential associations between treatment characteristics, cephalometric changes, and TMD symptoms.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"13 ","pages":"38"},"PeriodicalIF":0.0,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11698241/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142932098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative assessment of orthodontic treatments performed by graduate orthodontic students of an International School of Dentistry.","authors":"Mohsen Gholizadeh, Fahimeh Farzanegan, Farzin Heravi, Tarek El-Bialy","doi":"10.4103/jos.jos_41_24","DOIUrl":"https://doi.org/10.4103/jos.jos_41_24","url":null,"abstract":"<p><strong>Context: </strong>Assessing and monitoring treatment quality within graduate courses are vital for maintaining high standards and addressing areas needing improvement. In this study, we evaluated the treatment quality delivered by measuring the total scores obtained from the comprehensive clinical assessment (CCA) index and the objective grading system (OGS) index.</p><p><strong>Aims: </strong>This study aimed to evaluate the quality of orthodontic treatments administered by graduate students by using the CCA index and OGS index.</p><p><strong>Settings and design: </strong>The research was carried out at the Orthodontic Department of Mashhad School of Dentistry, focusing on a cross-sectional analysis of orthodontic treatments administered by graduate students.</p><p><strong>Methods and material: </strong>The study randomly selected 36 cases from the department's archives and evaluated them through pre- and post-treatment analyses, including radiographs, photographs, and dental casts. The evaluation employed the CCA and the OGS indices.</p><p><strong>Statistical analysis used: </strong>Data analysis was performed using the Spearman and Mann-Whitney tests.</p><p><strong>Results: </strong>The CCA correlated with the patient's age and gender and was statistically significant (<i>P</i> = 0.007 and <i>P</i> = 0.010, respectively). The CCA index was substantially associated with treatment duration (<i>P</i> = 0.032 a). There was no significant relationship between OGS and CCA (<i>P</i> = 0.223). The mean of post-treatment OGS was 18.97. All criteria of OGS and the overall score were improved significantly (<i>P</i> < 0.001).</p><p><strong>Conclusions: </strong>The results of this study suggested that orthodontic treatment results provided by the investigated program have high scores and meet high standards of the CCA and OGS indices.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"13 ","pages":"43"},"PeriodicalIF":0.0,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11698247/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142931445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of energy drinks on force degradation of elastomeric chains (An <i>in vitro</i> study).","authors":"Noor N Abbass, Alaa F Albo Hassan, Mohammed Nahidh","doi":"10.4103/jos.jos_43_24","DOIUrl":"https://doi.org/10.4103/jos.jos_43_24","url":null,"abstract":"<p><strong>Objectives: </strong>This <i>in vitro</i> study aimed to determine how three different energy drink types affected the force decay of three distinct brands of clear, short elastomeric chains over various time intervals.</p><p><strong>Materials and methods: </strong>In this study, 600 pieces of clear, short elastomeric chains from three brands were examined. The initial force was measured immediately using a digital scale and after 1, 7, 14, 21, and 28 days. These intervals followed immersion in the respective energy drink for 5 minutes twice daily. Using one-way ANOVA and Tukey's HSD tests, the percentage of force decay was computed and compared across the different elastic brands, time intervals, and energy drinks.</p><p><strong>Results: </strong>The force degradation of various elastic brands immersed in different energy drinks increased over time, following a similar pattern of decay. By the end of the fourth week, there were highly significant differences in the force decay percentage, varying from 68% to 83%.</p><p><strong>Conclusions: </strong>Considering the effects of brands, duration, and energy drinks, all the evaluated brands exhibited similar patterns of force decay, with highly significant differences noted. The force decay in Coca-Cola Energy and Fire ball drinks is relatively higher than in other beverages.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"13 ","pages":"40"},"PeriodicalIF":0.0,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11698242/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142931796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A cross-sectional study to correlate nasal profile and chin position with cephalometric lip profile.","authors":"Tania A Siddiqui, Rashna H Sukhia, Sarah Irfan, Ahmad Hasan, Mubassar Fida","doi":"10.4103/jos.jos_28_24","DOIUrl":"https://doi.org/10.4103/jos.jos_28_24","url":null,"abstract":"<p><strong>Objective: </strong>To determine the effect of the nose and chin on the cephalometric lip profile.</p><p><strong>Methods and material: </strong>The pre-treatment lateral cephalograms of 177 adult patients with no history of orthodontic treatment were manually traced. The sample size was divided into three vertical and horizontal groups using angle ANB and MMA to assess the difference in nose and chin forms. The horizontal and vertical groups were analyzed using One-way ANOVA and Kruskal-Wallis. The Independent sample <i>t</i>-test and Mann-Whitney <i>U</i> were used for comparison between the two genders. The correlation of nose and chin with E, S line, and nasolabial angle was done using the Spearman correlation coefficient while the effect was assessed using linear regression analysis.</p><p><strong>Results: </strong>Among the nasal variables, columellar length inversely affects the linear position of the upper lip and this was statistically significant. The nasolabial angle is also affected by the inclination of the nasal base and this was statistically significant. The linear distance of the soft tissue chin in relation to the maxilla has the most effect on the position of the upper lip. It is notable that all hard and soft tissue chin variables inversely affected the linear position of the upper and lower lips.</p><p><strong>Conclusions: </strong>The quantitative measure of the effect of the nose and chin on lips is important as it allows clinicians to determine the overall effect of adjunctive procedures at pretreatment levels. Thus, corrective procedures such as rhinoplasty or genioplasty can be done at pre-orthodontic treatment stages to create a better treatment plan for patients.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"13 ","pages":"39"},"PeriodicalIF":0.0,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11698244/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142932082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the characteristics of the mandibular canal in cone beam CT.","authors":"Thao Thi Do, Lam Nguyen Le, Loc Truong Tan, Anh The Thien Dang, Duyen Ngoc Kim Huynh, My Hoan Truong, Luan Minh Nguyen","doi":"10.4103/jos.jos_47_24","DOIUrl":"https://doi.org/10.4103/jos.jos_47_24","url":null,"abstract":"<p><strong>Context: </strong>The mandibular canal (MC) is an essential landmark that should be considered before any surgeries. Therefore, accurately assessing the location and characteristics of the MC in cone beam computed tomography (CBCT) imaging is very important.</p><p><strong>Aims: </strong>To determine the characteristics of the MC in relation to adjacent anatomical structures in CBCT projections.</p><p><strong>Settings and design: </strong>The convenience sampling method.</p><p><strong>Methods and material: </strong>This was a retrospective study of 112 CBCT images of Vietnamese patients aged 18 to 69 years, taken for clinical indications between 2018 and 2023. The evaluation was carried out by comparing and arranging the anatomical structures of different planes in three-dimensional space to assess and measure relevant dimensions.</p><p><strong>Statistical analysis used: </strong>Independent samples T-test.</p><p><strong>Results: </strong>The average diameter of the MC from the apex of the second premolar to the distal apex of the second molar, if there were no missing teeth in this segment, was 2.58 ± 0.52 mm (right) and 2.55 ± 0.54 mm (left). If there were a missing tooth in this segment, the measurements were 2.51 ± 0.79 mm (right) and 2.47 ± 0.45 mm (left). The difference between the two sides regarding the presence or absence of a missing tooth was not statistically significant.</p><p><strong>Conclusions: </strong>The precise localization of the MC related to the tooth apex and the diameter of the MC can vary in each person. CBCT indications should be considered when establishing treatment planning to avoid damaging the inferior alveolar nerve in the MC.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"13 ","pages":"45"},"PeriodicalIF":0.0,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11698245/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142931055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of pH on the release of nickel ions from fixed orthodontic appliances in artificial saliva.","authors":"Youssouf Ouédraogo, Abdoul Karim Sakira, Moussa Ouédraogo, Issa Tapsoba, Tarcissus Konsem, Jean Bertin Beugré","doi":"10.4103/jos.jos_8_24","DOIUrl":"https://doi.org/10.4103/jos.jos_8_24","url":null,"abstract":"<p><strong>Aim: </strong>The aim of this study was to make a laboratory assessment of pH influence on the kinetics of the release of nickel ions in artificial saliva.</p><p><strong>Methods and material: </strong>In this study, 15 basic orthodontic appliances are immersed in 15 polyethylene tubes each containing 40 ml of artificial saliva. Tubes were divided into three sub-groups of 5 tubes depending on the pH: pH 5, pH 7 and pH 8. The release of nickel ions was measured using atomic absorption spectrometry in a sample of 5 ml of artificial saliva taken one hour, four hours and one hundred and sixty-eight hours after immersion in a water bath at 37°.</p><p><strong>Statistical analysis used: </strong>Significance threshold <i>P</i> was set at 0.05. A Student T test and the 2-way Anova test (with a Bonferoni post-test) were used respectively to compare the means.</p><p><strong>Results: </strong>The neutral pH causes a low release of nickel ions. The release kinetics of nickel ions is minimal for neutral pH, it increases when pH varies. After one hour of immersion, the nickel released did not reach the spectrometer quantification threshold as for neutral and acid pH. The alkaline pH causes an average release of nickel ions from the beginning without kinetic variation. As time passes (T3), the acidic pH causes more nickel ions release through a succession of oxidation-reduction reactions. After 168 hours, the average mass of nickel released is 0.30 µg for pH 7, 1.35 µg for pH 8 and up to 2.85 µg for pH 5.</p><p><strong>Conclusions: </strong>Quantities released did not reach nickel toxicity threshold in humans. Orthodontists must consider the potential risk of hypersensitivity due to nickel in fixed orthodontic appliances.</p>","PeriodicalId":16604,"journal":{"name":"Journal of Orthodontic Science","volume":"13 ","pages":"49"},"PeriodicalIF":0.0,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11698249/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142932170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}