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OBJECTIVE: To evaluate the effect of four different photoactivation protocols (according to "photoactivated faces" - mesial/distal, cervical/incisal or center - and "photoactivation time" - 6-3 s) of a high-power photo activator (Valo Cordless®-Ultradent) on the shear bond strength (SBS) between metal brackets and dental enamel and on the degree of conversion (DC) of an orthodontic resin. MATERIALS AND METHODS: 40 bovine incisor crowns were randomly assigned to 4 groups (n = 10). The brackets were bonded with Transbond XT® resin using 4 protocols according to the "photoactivation protocol" factor (which was subdivided into photoactivated faces and photoactivation time): V3C = 3 s + center; V6C = 6 s + center; V3M3D = 3 s on mesial + 3 s on distal; V3C3I = 3 s on cervical + 3 s on incisal. All the samples were stored for 4 months (water,37ºC) and then subjected to a SBS test (100KgF,1 mm/min). 40 resin discs were made to evaluate the monomer degree of conversion. Data from the SBS and DC were assessed by One-way ANOVA and Tukey's test (5%). Bond failures were analyzed according to the Adhesive Remnant Index (ARI) and evaluated by the Kruskal-Wallis test (5%). RESULTS: There was a statistically significant difference (p = 0.008) in the One-way ANOVA result for SBS values between all groups, but the protocols showed statistically similar results (p ≥ 0.05-Tukey's tests) concerning the photoactivated faces (V6C, V3M3D and V3C3I) and photoactivation time (V3C and V6C) factors individually. There was no statistically significant difference (p ≥ 0.05) in the One-way ANOVA result for DC values. CONCLUSION: The SBS and DC values will vary depending on the protocol applied. CLINICAL RELEVANCE: It is possible to maintain the bracket fixation quality with the use of a high-power LED photo activator associated with a shorter photoactivation time. However, it is assumed that not all types of protocols that might be applied will provide quality bonding, such as V3C, V3M3D and V3C3I, which may - depending on the SBS and DC values - affect the final treatment time, due to brackets debonding, or increase of possibility of damage to dental enamel during bracket removal. Clinical studies are suggested to confirm the hypotheses of this research.

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OBJECTIVES: To evaluate the 3D accuracy of attachment positioning and the adaptation of aligners to attachments using in-house templates made with either polyethylene terephthalate glycol (PETG) or ethylene-vinyl acetate (EVA) and either pressure or vacuum thermoforming machines. MATERIALS AND METHODS: Overall, 140 test specimens were resin-printed. Templates for the attachment bonding were made with 1-mm EVA or 0.5-mm PETG laminates. Orthodontic aligners were manufactured with 0.75-mm PETG. The thermoplastification process was carried out using either vacuum or pressure machines. The positional differences between the virtual and bonded attachments were assessed in the X, Y and Z coordinates. The marginal adaptation between the aligners and the attachments was measured. RESULTS: Minor inaccuracies in the positioning of the attachments were observed in all combinations of thermoforming machines and plastic laminates used to fabricate the templates, mainly in the superior-inferior (Z) dimension. PETG performed better than EVA in the anterior region (p < .05). No association was found between thermoplastification machines and the accuracy of the positioning of the attachments (p > .05). While small misadaptations between the aligners and the attachments were observed, the EVA templates performed better than the PETG templates. CONCLUSIONS: The inaccuracy of the attachment positioning and the misadaptation of the aligners to the attachments were slight. The vacuum and pressure thermoplastification machines showed no difference in attachment positioning accuracy. The PETG template was better than the EVA template in the anterior region, but the EVA attachments presented a better adaptation to the aligners than the PETG attachments.

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PURPOSE: This two-arm parallel randomized controlled trial aimed to evaluate and compare periodontal changes due to rapid maxillary expansion (RME) using tooth-bone-borne and tooth-borne devices in growing patients via clinical examinations and cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Forty-two eligible patients (aged 11-14 years; transverse maxillary deficiency, posterior crossbite) were screened and divided into two groups based on the treatment received (randomization was performed using computer-generated numeric sequences): hybrid hyrax tooth-bone-borne group (TBB) and hyrax tooth-borne group (TB). The primary outcome was the change in cortical bone thickness (by CBCT). In addition, the clinical attachment level (CAL), gingival recession, and bleeding were assessed. Both examinations were performed before and 3 months after the activation phase. Intergroup comparisons were performed using analysis of covariance (ANCOVA; P < 0.05). RESULTS: Twenty-one patients (12 girls and 9 boys; mean initial age, 13.3 years) were included in the TBB group and 21 (5 girls and 16 boys; mean initial age, 13.2 years) were included in the TB group. The TB group exhibited a decrease in buccal bone thickness in the first premolars and first molars at all three evaluated levels. Specifically, tooth 14 at 3 mm from the enamel-cement junction showed a significant width reduction (0.7 mm; p < 0.001), accompanied by a notable increase in palatal cortical thickness at 6 mm of enamel-cement junction (1.13 mm; p < 0.001). CONCLUSIONS: RME resulted in buccal bone thickness reduction at the first premolar with hyrax treatment. In the molar region, both devices resulted in cortical bone alterations that were less pronounced in the TBB group.

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One of the biggest controversies in current orthodontics is determining the appliance to use, since today patients seek better results in shorter times, in addition to putting aesthetics first. OBJECTIVE: compare the benefits and disadvantages that arise when using fixed orthodontic appliances and transparent aligners. MATERIALS AND METHODS: An investigation and compilation of specialized bibliographic information on the topic was carried out in scientific search engines such as PubMed, SciElo and Web of Science between the years 1991 to 2023, focused on research work related to the effects of the use of orthodontic appliances. fixed compared to clear aligners. RESULTS: The review was carried out based on 53 articles found that met the selection criteria. CONCLUSION: Fixed orthodontic appliances are better in complex cases, they are more precise and less likely to relapse; Transparent aligners are more aesthetic, hygiene is more affective and the bone density of the mandibular condyle decreases.

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This study aimed to evaluate the effects of the estrogen depression during orthodontic tooth movement on alveolar bone microarchitecture and periodontal ligament. Female Wistar rats were divided into two groups, one consisting of non-ovariectomized animals subjected to orthodontic tooth movement, and one comprising ovariectomized animals subjected to orthodontic tooth movement. Micro-CT assessment of bone volume to total volume (BV/TV), total porosity, trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.Sp) in the alveolar bone of the orthodontically moved tooth was performed. Histomorphometric analyses were made in the periodontal ligament, and immunoexpression of RANK, RANKL, OPG, and TUNEL were quantified. Orthodontic tooth movement in the group of ovariectomized rats was faster than in non-ovariectomized animals. The alveolar bone area showed lower values of BV/TV and trabecular thickness, and higher bone porosity and trabeculae numbers in the ovariectomized rats. Histological analyses in the ovariectomized group revealed an increase in collagen fibers in the periodontal ligament. The apoptotic cell counts in the periodontal ligament were higher in the group of ovariectomized rats than in the sham-operated rats. Ovariectomy resulted in an increase in tooth movement and alteration of the alveolar bone microstructure in the first 7 day of orthodontic tooth movement, and in the presence of apoptotic cells in the periodontal ligament.

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OBJECTIVES: To investigate artefacts produced by different orthodontic brackets and wires in cone-beam computed tomography (CBCT) scans. MATERIALS AND METHODS: Two dental arches were made using extracted human teeth and plaster. Three pairs of acetate plates containing different brackets - metallic, ceramic, and self-ligating ceramic with NiTi clip - along with a control plate (i.e., without brackets) were prepared. Wire changes (NiTi and steel) were made during CBCT acquisitions, performed with a fixed exposure protocol. Axial slices were selected for mean gray values and standard deviation measurement in three regions of interest (buccal, lingual, and tooth). Noise and contrast-to-noise ratio (CNR) were calculated and compared among the different brackets and wires by ANOVA with a significance level of 5%. RESULTS: Overall, the buccal and tooth region were mostly affected by the metallic and self-ligating brackets, showing higher noise, and lower CNR (p < 0.05). On the other hand, less impact of ceramic brackets in the image quality was observed (p ≥ 0.05). The lingual region did not show expressive differences among the brackets and wire combinations (p ≥ 0.05). The presence of wire associated with the brackets did not worsen image quality (p ≥ 0.05). CONCLUSIONS: In conclusion, metallic and self-ligating brackets have greater artefact expression than ceramic brackets. The wire did not influence image quality. CLINICAL RELEVANCE: One should pay attention to the type of brackets when requesting a CBCT scan during treatment, as metallic and self-ligating brackets may express greater artefacts than ceramic brackets.

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BACKGROUND: There are several publications that show the efficacy of surgical interventions in accelerating the rate of tooth movement in orthodontics. Consequently, possible adverse effects must also be evaluated. OBJECTIVES: The aim of the present study was to compare the perception of pain and root resorption between orthodontic treatment with a surgical acceleration intervention vs. conventional orthodontic treatment. MATERIAL AND METHODS: An electronic search was conducted in the MEDLINE, Scopus, Web of Science (WoS), ScienceDirect, Cochrane Library, and Virtual Health Library (VHL) databases up to September 12, 2022. Randomized or non-randomized, controlled, parallel-arm or split-mouth clinical trials were included. Fixed-and random-effects meta-analyses were performed with regard to heterogeneity. The risk of bias (RoB) was assessed using the RoB 2.0 and ROBINS-I tools. RESULTS: A total of 1,395 articles were initially retrieved, 40 studies were finally included in the review and 15 studies were eligible for quantitative analysis. The meta-analysis showed a significant difference in pain perception between acceleration surgery vs. conventional orthodontics at 24 h (p = 0.040); however, this difference was not significant at 7 days (p = 0.080). Overall, the patients who underwent any acceleration procedure presented significantly less resorption as compared to those who were applied conventional treatment (p < 0.001). A similar significant difference was found in retraction movements (p < 0.001) and alignment movements (p = 0.030). CONCLUSIONS: In the first 24 h, surgical interventions for the acceleration of tooth movement produce a greater perception of pain as compared to conventional orthodontic treatment, but the perception is similar after 7 days. Acceleration surgery results in less root resorption - in alignment movements, and especially in retraction movements.

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Gingival enlargement is a common clinical sign in the gingival diseases associated with orthodontic treatment. Its biological mechanisms are not completely understood; nevertheless, the biochemical changes associated with these inflammatory and overgrowth processes could alter the post-translational protein modifications occurring in various locations within the mouth. Here, changes in the profiles of the carbonylated and phosphorylated proteins in saliva were examined in donors with gingival enlargement (seven men and seven women) and healthy donors (six men and eight women). The sociodemographic characteristics of both groups did not present significant differences. Carbonylation was measured by a quantitative immunoassay (Dot Blot), whereas the profiles of the phosphorylated proteins were visualized by SDS-PAGE with quercetin staining. Some phosphopeptides were also identified using a typical LC-MS-MS approach. Our results showed that gingival enlargement induced a significant increase in oxidative damage in salivary proteins. While a significant reduction in phosphorylation was observed at the stain level in SDS-PAGE, there was a slight increase in the number of phosphorylated proteins identified by MS in samples with gingival enlargement.

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This dataset features 200 sagittal projection images derived from Cone Beam Computed Tomography (CBCT) scans, corrected according to the Natural Head Position (NHP) guidelines proposed by Fredrik Lundström and Anders Lundström. The images originate from orthodontic patients in Cali, Valle del Cauca, Colombia, encompassing both initial phases and ongoing treatments. The dataset is divided into two groups: 100 images from female subjects (CoF) and 100 from male subjects (CoM), facilitating gender-specific studies. The dataset is accompanied by an Excel file ``Data info.xlsx'' that details the rotation angles in the axial (Yaw), coronal (Roll), and sagittal (Pitch) planes, along with the pixel size and image dimensions. This detailed documentation supports the replication of studies and aids in the interpretation of cephalometric analyses. Corrections made to align the images with NHP standards involve adjustments in the three main anatomical planes using points from the frontozygomatic suture (Fz) in the axial and coronal planes, and sella (S) and nasion (N) for the sagittal plane.

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BACKGROUND: Junctional epidermolysis bullosa (JEB) is one of the four major types of EB caused by genetic variants in the genes coding the proteins of the lamina lucida. All patients with this major type of EB present syndromic hypoplastic amelogenesis imperfecta (AI), with either a pits and fissures or generalized hypoplastic phenotype. Severe forms of AI are associated with compromised oral health-related quality of life (QoL) mostly due to poor dental aesthetics, dentofacial anomalies, and oral pain. AIM: To present the comprehensive dental treatment of a patient with JEB and AI from the age of 20 months until the age of 18 years, including complex orthodontics and digital oral rehabilitation. MATERIALS AND METHODS: A male patient with intermediate JEB (homozygous c.3228+1G>A LAMB3 variant) has been under the care of the special care dentistry clinic of the University of Chile since the age of 20 months. His complex dental needs include structural enamel abnormalities in primary and permanent dentition (hypoplastic generalized AI), severe dental crowding with maxillary compression, Class III skeletal pattern, agenesia (#45), and gingivitis. RESULTS: Pediatric dental care included oral hygiene education and preventive strategies (prophylaxis and fluoride applications), maintaining the dentition free of caries. Due to AI, severe tooth sensitivity hindered proper oral hygiene and required early rehabilitation with temporary polycarbonate and metallic crowns. At the age of 16, the patient began orthodontic treatment. A maxillary expansion was performed with two consecutive mini-implant assisted rapid palate expansion (MARPE) bonded to four mini-implants in the palate. After finishing orthodontic treatment metallic multibrackets (duration 19 months), a definitive oral rehabilitation based on digital smile design with feldspathic crowns of all anterior teeth and premolars was performed. CONCLUSION: Patients with severe generalized hypoplastic syndromic AI associated with JEB benefit from long-term preventive oral care. Complex orthodontic techniques, such as MARPE, and multibrackets can be successfully. Digital smile design provides a definitive oral rehabilitation technique improving oral function, aesthetics, and QoL.