Search Results (109)

Background: Canine impaction complicates treatment and prolongs duration, requiring precise localization. CBCT is the gold standard for diagnosis and assessment. However, it involves high radiation exposure and cost. This study aimed to evaluate the effectiveness of a combined biomechanical approach for orthodontic traction of impacted maxillary canines (IMCs) and to determine whether intraoral scans (STL files) could replace a final CBCT in assessing canine repositioning. Methods: The sample included 10 patients (7 males and 3 females) with 13 severely displaced IMCs, treated with a protocol combining Invisalign^® aligners, elastics, mini-implants, and sectional wires. In all, 9 IMC were palatally impacted, while 4 were buccally impacted. A representative clinical case is presented to illustrate the biomechanics used in one of the complex cases. Canine movement was evaluated at the cusp and apex through two methods: overlay of pre- and post-treatment CBCTs, and overlay of initial and final STL scans onto the initial CBCT. Results: A Class I canine relationship was successfully achieved in all patients. No statistically significant differences were found between the two measurement methods (p > 0.05). Conclusions: Orthodontic traction of IMC, especially in complex cases, can be achieved using aligners, elastics, mini-implants, and sectional wires. Once the canine crown has erupted and is clinically visible, STL scans overlaid with the initial CBCT can accurately assess the final position of the crown and root. This allows clinicians to avoid a second CBCT in selected cases, reducing patient radiation exposure while maintaining diagnostic accuracy. Full article

Fluoride mouthwashes are often recommended by dental professionals due to their proven benefits for oral hygiene. However, it is vital to acknowledge that these products may have undesirable effects on orthodontic treatment outcomes, particularly by altering the biomechanical properties of orthodontic devices and their components. To gain a comprehensive understanding of this potential issue, an extensive and systematic search was conducted across seven distinct databases. PRISMA extension for scoping reviews (PRISMA ScR) guidelines were followed. Following a detailed evaluation and careful scrutiny of the available evidence, a total of seven relevant studies met the inclusion criteria and were incorporated into the current scoping review. Findings indicated that regular intraoral use of fluoride-containing mouthwashes could lead to heightened corrosion and greater release of metal ions from stainless-steel brackets and nickel–titanium (NiTi) archwires. Additionally, the mechanical properties and structural integrity of titanium–molybdenum alloy (TMA) wires were negatively influenced by exposure to fluoride mouthwashes. Although existing evidence highlights these potential drawbacks, there remains a clear necessity for additional comprehensive research. Given the possibility that fluoride mouthwashes could adversely influence orthodontic treatment effectiveness, orthodontists and dental clinicians must exercise cautious judgment and deliberate consideration when prescribing fluoride-based mouthwashes for patients undergoing orthodontic therapy. Full article

Silver nanoparticles (AgNPs) have emerged as a promising antimicrobial agent in dentistry due to their distinctive physicochemical characteristics and broad-spectrum biocidal activity. For example, silver nanoparticles can be incorporated into oral hygiene products in preventive dentistry, composite resins in restorative treatment, irrigation solutions in endodontic treatment, membranes for guided tissue regeneration in periodontal treatment, acrylic resins and porcelains in prosthodontic treatment, coatings in dental implant treatment, and brackets and wires in orthodontic treatment. This paper focuses on summarizing the current knowledge on the antimicrobial use of silver nanoparticles in dentistry, highlighting their antimicrobial mechanism and potential applications in clinical treatment. The literature indicates that silver nanoparticles are a promising antimicrobial agent in dentistry. However, there are still many issues including fundamental antibacterial mechanisms that need to be completely elucidated before clinical applications. Full article

Background/Objectives: The growing demand for esthetic, less painful, and more comfortable orthodontic treatment has led to increasing use of aligner systems. Initially used for less complicated malocclusions, aligners are now being incorporated into complex treatment plans, including cases involving impacted teeth. While aligners are a popular alternative to traditional fixed appliances, they still have limitations. This study aims to evaluate the effectiveness of aligner-based orthodontic treatment in patients with impacted or significantly ectopic canines. Methods: This study was conducted in accordance with the PRISMA guidelines. The search terms used were as follows: ‘Clear Aligner’ OR ‘Invisalign’ AND ‘Impacted Canine’ OR ‘Impacted Tooth’ OR ‘Ectopic Tooth’ OR ‘Ectopic Canine.’ A total of 1101 records were identified, of which 170 articles underwent screening. Fifteen articles were assessed for eligibility, and ultimately six case reports and one three-dimensional finite element analysis (FEA) study were included for both quantitative and qualitative synthesis. Results: According to the studies, additional appliances are often required to achieve favorable outcomes when treating impacted canines with aligner systems. Temporary anchorage devices (TADs) were used in 5 out of 9 reported cases for canine traction into the dental arch. In three cases, TADs were combined with sectional wires implemented as cantilevers. Elastics were used in 6 out of 9 cases for traction to the opposite arch, and in 5 out of 9 cases as interarch elastics attached to the aligners. Interarch elastics were applied in various ways, either directly to the aligners or to primary canines using hidden buttons inside pontics or dovetail hooks. Elastics were also anchored to the lower arch with class II, class III, or cross-arch (criss-cross) mechanics. Conclusions: This review highlights the promising potential of aligner systems in the treatment of impacted canines. However, additional auxiliaries, such as TADs, sectional wires, or elastics remain nearly essential for initial canine traction. Aligner systems offer versatile treatment options, and the possibility of reduced treatment time represents a valuable area for future research. Full article

Background/Objectives: Delayed tooth eruption (DTE) is a very challenging clinical situation, and the pathogenesis has been associated with local, systemic, and genetic factors. The aim of this presentation is to describe the management of such a case with delayed eruption of mandibular central incisors and canines. Methods: An 11-year-old female patient presented with DTE involving lower incisors (32, 42) and canines, seeking orthodontic treatment. Furthermore, lower permanent central incisors were congenitally missing while lower deciduous incisors were still in place. After a year-and-a-half of just monitoring the case and having suggested the extraction of deciduous first molars and canines, orthodontic treatment started with fixed appliances in the upper and lower jaw. First and second premolars gradually erupted after the precursor’s extraction. Lower canines and the two existing incisors were, after several months, surgically exposed and a gold chain apparatus was bonded on each one, while the closed eruption technique was chosen. A 0.17 × 0.25 stainless steel (SS) lingual wire, leaning on the buccal tubes of the lower molar bands and properly manipulated around them, was fitted in conjunction with the labial brackets and wires in order to facilitate the traction of the impacted teeth, which was carried out for one after the other using either an elastic chain or a second super-elastic wire. Results: All impacted teeth were finally restored to their proper place. The root of 71 did not present resorption, so the tooth was maintained in the lower arch while inter-proximal reduction was performed in the upper arch in the anterior region, in order to anticipate the lower missing incisor. Finally, a stable occlusion with proper contacts was achieved. Conclusions: Proper diagnosis, on-time extractions of deciduous teeth, and a well-designed treatment plan regarding space management and orthodontic traction of impacted teeth contributed to successful treatment outcomes in this DTE case. Full article

Objectives: The objectives of this study were to investigate in vitro BPA release from two common fiberglass fixed lingual canine-to-canine retainers and to compare these amounts with those released from a conventional multistranded stainless-steel orthodontic retainer. Methods: Fifty-four recently extracted teeth were divided into groups of six teeth each, formed in an arch shape. Three different retainer types were evaluated: Ribbond, EverStick Ortho and Wildcut wire. Three identical specimens were constructed for each retainer type. BPA release was determined with validated the liquid chromatography–tandem mass spectrometry method at 1 and 24 h, as well as at 7, 14 and 30 days. The method’s limits of detection and quantification were 0.32 ng/mL and 0.96 ng/mL, respectively. A two-way mixed, repeated-measures analysis of variance with Greenhouse–Geisser correction was employed to verify the existence of any significant differences. Results: Higher levels of BPA were released from the polyethylene fiber and glass fiber retainer in comparison with the conventional retainer in the present study. The differences between the systems over time were not statistically significant at the 95% confidence level. Conclusions: In vitro BPA release during the first month did not differ between the examined retainer types. The highest BPA concentrations were observed at 1 month. Full article

The quad-helix and W-arch are commonly used appliances for expanding the dental arch in orthodontic treatment. However, differences in performance between these two expanders remain unclear, and no guidelines exist for selecting one over the other. The purpose of this study was to investigate whether there were differences in dental arch expanding ability between these appliances. Maxillary arch expansions were simulated using the finite element method. The expander was assumed to be an elastic beam, while the teeth and alveolar bone were treated as rigid bodies. The periodontal ligament (PDL) was modeled as a nonlinear elastic material. The teeth moved in the same direction as the initial movement caused by the elastic deformation of the PDL. The right and left canines, premolars, and first molars were expanded symmetrically in either parallel or fan shapes. When the wire diameter of the W-arch was set to 0.032 inches its stiffness became equivalent to that of a quad-helix with a wire diameter of 0.036 inches. Canines and premolars were expanded through tipping movements. The molars initially tipped buccally, then became upright and moved bodily. Both expanders expanded the arch in almost the same manner. There was no difference in arch expansion ability between the W-arch made of 0.032-inch wire and the quad-helix made of 0.036-inch wire. The W-arch may be preferred as the first choice due to its simpler structure compared to the quad-helix. Full article

Rationale: Orthodontic archwires undergo chemical and structural changes in the complex intraoral environment. The present work aims to investigate the safe duration for intraoral use (related to the nickel release hypothesis) of different types of nickel-containing wires. By analyzing how the nickel content (NC) varies over time, we aim to provide practical recommendations for the optimal use of said archwires. Materials and Methods: Our analysis focuses on the following nickel-containing archwires: stainless steel, Ni-Ti superelastic, heat-activated NiTi and CuNiTi, and multi-force archwires. The studied archwires of each type were divided into three groups: group 1, as received; group 2, retrieved after intraoral exposure for less than 6 weeks; group 3, used for more than 8 weeks. To assess NC, measurements using scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and laser-induced breakdown spectroscopy (LIBS) were performed in multiple regions of each wire. Statistical analysis of the measured values using one-way ANOVA and multiple group comparisons showed significant differences in nickel content between groups. The dynamic behavior of the statistical results for NC was then modeled using logistic regression and fitted with cubic splines. Conclusions: The proposed behavior model, with further refinement, could enable orthodontists to make informed, patient-specific decisions regarding the safe and effective use of orthodontic floss. The overall conclusion of the study is that due to stability, SS-CrNi, HA-Ni-Ti with Cu, and TriTanium^TM are suitable for long-term use, and due to higher nickel release, Ni-Ti-Superelastic, HA-Ni-Ti without Cu, and Bio-Active^TM are better for short- to medium-term use. Full article

Background: Traditional methods for palatal expansion using fixed appliances often face limitations in comfort and aesthetics. In comparison, aligner therapy has limitations, particularly regarding maxillary expansion. The aim of this study is to examine the biomechanical properties regarding the wire diameter and bending of different stainless steel wires to evaluate their potential for incorporation into maxillary aligner therapy. Materials and Methods: Three rectangular stainless steel wires (0.016″ × 0.022″, 0.017″ × 0.025″, and 0.019″ × 0.025″) were tested for mechanical expansion forces in the intermolar region, comparing non-tooth-shaped bent wires (A groups) and tooth-shaped bent wires (B groups). Using a Z010 testing machine (ZwickRoell GmbH and Co. KG, Ulm, Germany), expansion forces were measured at 1 mm intervals over a 5 mm distance, with 15 samples analyzed per group. Statistical analyses included the Shapiro–Wilk test for normal distribution, the Mann–Whitney U test, which revealed significant results (U = 225, p < 0.001), and the Kruskal–Wallis test, which indicated significance (H = 39.130; df = 2; p < 0.001). Results: Tooth-shaped bent wires exhibited significantly lower expansion forces than non-tooth-shaped bent wires for all tested wire types. This difference was most notable in wires with larger transverse profiles (0.019″ × 0.025″), where the tooth-shaped bent wires displayed a marked reduction in mechanical load capacity. Specific force measurements for non-tooth-shaped wires ranged from 760.61 ± 79.51 mN at 1 mm of deformation to 2468.46 ± 66.27 mN at 5 mm of deformation, while tooth-shaped wires ranged from 116.80 ± 3.74 mN to 1979.49 ± 23.23 mN. Conclusions: These findings suggest that non-tooth-shaped bent wires offer a more efficient and uniform expansion potential for maxillary movements due to their stable elastic properties. Clinically, integrating non-tooth-shaped stainless steel wires into aligner therapy may provide a viable method for maxillary expansion, supporting both first- and second-order movements in orthodontic treatment. Further research is needed to explore the integration of such wires for effective maxillary expansion in aligner therapy. Full article

This study investigates the release of metal ions from commonly used orthodontic archwires, specifically, stainless steel (SS), nickel–titanium (NiTi), chromium–cobalt (CrCo), and titanium–molybdenum (TMA) alloys. To simulate oral conditions, each type of wire was immersed in artificial saliva at body temperature for a four-week period. Ion release levels were analyzed through ICP-OES mass spectrometry. The findings indicate that NiTi and CrCo wires released significantly higher amounts of nickel (Ni) and chromium (Cr) ions compared to SS wires. These findings underscore the potential risk of allergic reactions, particularly to nickel, and emphasize the need for careful consideration of biocompatibility in orthodontic material selection. This research also provides valuable insights aimed at minimizing adverse reactions in patients, especially those with metal allergies. Full article

Background: The treatment of mandibular second molar (MM2) impaction presents a challenge for orthodontists and requires a surgical–orthodontic approach. This study aims to compare the effectiveness of two techniques for treating impacted MM2: a traditional technique using brass wire and a technique employing skeletal anchorage. Methods: Twelve MM2 with mesio-angular impaction, with an inclination angle between 25° and 40° and an impaction depth between 4 and 10 mm, were selected and randomly divided into two treatment groups. Patients in Group A were treated using the traditional brass wire technique, while those in Group B underwent treatment with a skeletal anchoring technique that utilized a miniscrew positioned in the retromolar region and an elastic sling chain. For both groups, treatment time and the influence of the disimpaction technique on oral health-related quality of life (OHRQoL) were evaluated using the short-form Oral Health Impact Profile (OHIP-14). Results: The results indicated an average treatment time of 168.67 ± 52.32 days for Group A and 76 ± 10.17 days for Group B, with a statistically significant difference (p-value = 0.0002). Regarding the impact on the patients’ OHRQoL, Student’s t-test did not reveal a statistically significant difference between the two groups at 3 and 7 days of follow-up. Conclusions: Both techniques are considered effective for the treatment of impacted MM2 (angulation 25–40°, depth 4–10 mm). The use of skeletal anchorage significantly reduces treatment times without negatively affecting OHRQoL. The results of this study should be confirmed by further studies with larger sample sizes. Full article

Legislative framework addresses the issues of alloy corrosion, demanding the restricted use of probable carcinogenic, mutagenic, and toxic-for-human-reproduction (CMG) metals like nickel, cobalt, and chromium and demanding the development of new biomaterials. The aim of this research was to evaluate and compare the ion release of standard dental alloys and their hypoallergenic equivalents. Six types of orthodontic alloy wires (nickel–titanium (NiTi), coated NiTi, stainless steel (SS), Ni-free SS, and cobalt–chromium (CoCr) and titanium–molybdenum (TMA) were immersed into artificial saliva of pH 5.5 and 6.6. Release of metal ions was measured by inductively coupled plasma–mass spectrometry after 3, 7, 14 and 28 days. The data were analyzed using analysis of variance, and results with p < 0.05 were considered significant. NiTi released more Ti and Ni ions compared to the coated NiTi; SS released more iron, chromium, and nickel compared to the nickel-free SS. CoCr released cobalt in a high concentration and low amounts of chromium, nickel, and molybdenum compared to the molybdenum and titanium released by TMA. Release of metals from dental orthodontic alloys in vitro was overall lower at pH 6.6 and for the hypoallergenic equivalents when compared to standard dental alloys. Full article

This study investigates the cytotoxicity of various orthodontic archwires, which are essential in directing tooth movement through biomechanical forces. With advancements in material science, different archwire materials have been developed to balance mechanical performance with aesthetic and biological considerations. The study focuses on evaluating the biocompatibility and mechanical properties of stainless steel, nickel–titanium, and chromium–cobalt archwires, particularly their cytotoxic effects on oral cavity cells. In vitro cell culture experiments with fibroblasts, combined with scanning electron microscopy (SEM) analysis, were conducted to assess cell viability and morphology. The results revealed significant differences in cytotoxicity, with copper wires showing high toxicity and causing extensive cell death, while nickel–titanium and chromium–cobalt wires supported better cell viability and healthier cell morphology. These findings highlight the importance of selecting archwire materials that ensure mechanical efficiency without compromising cellular health, emphasizing the need for ongoing assessment of material biocompatibility in the oral environment. Full article

The development of the finite element method (FEM) combined block polynomial interpolation with the concepts of finite difference formats and the variation principle. Because of this combination, the FEM overcomes the shortcomings of traditional variation methods while maintaining the benefits of current variation methods and the flexibility of the finite difference method. As a result, the FEM is an advancement above the traditional variation methods. The purpose of this study is to experimentally highlight the thermal behavior of two stomatognathic systems, one a control and the other presenting orthodontic treatment by means of a fixed metallic orthodontic appliance, both being subjected to several thermal regimes. In order to sustain this experimental research, we examined the case of a female subject, who was diagnosed with Angle class I malocclusion. The patient underwent a bimaxillary CBCT investigation before initiating the orthodontic treatment. A three-dimensional model with fully closed surfaces was obtained by using the InVesalius and Geomagic programs. Like the tissues examined in the patient, bracket and tube-type elements as well as orthodontic wires can be included to the virtual models. Once it is finished and geometrically accurate, the model is exported to an FEM-using program, such as Ansys Workbench. The intention was to study the behavior of two stomatognathic systems (with and without a fixed metallic orthodontic appliance) subjected to very hot food (70 °C) and very cold food (−18 °C). From the analysis of the obtained data, it was concluded that, following the simulations carried out in the presence of the fixed metallic orthodontic appliance, significantly higher temperatures were generated in the dental pulp. Full article

Background: The need to perform occasional or continuous MRI exams and the interference with metal orthodontic appliances might be important and take a primary role during retention since the retention period is significantly longer than orthodontic treatment. Several non-metallic materials were proposed as potential alternatives to perform fixed retainers in orthodontics, but they showed internal limits. Methods: Polyetheretherketone (PEEK) was used in the present clinical report as a fixed orthodontic retainer in the lower arch in order to perform an appliance with mechanical properties comparable to metallic ones but with a higher biocompatibility material and without the need for removal in case of an MRI exam. The retainer wire was handmade in the studio and then shaped to fit the arch. Results: PEEK showed a good capability for constructing a lingual fixed retainer compared to other aesthetic non-metallic and metallic materials. Conclusions: To the best of our knowledge, this study proposes how to easily build a retainer in PEEK and provides a clinical example of how this material can be beneficial. Full article