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The aim of study was to evaluate periodontal conditions of upper canines and second premolars with and without proximal contact of individuals undergoing orthodontic treatment associated to extractions of the upper first premolars. The study selected upper canines and premolars of individuals undergoing orthodontic treatment without extractions (30 hemiarches - control group), or with extraction of the upper first premolars and whose canines and second premolars had interproximal contact (16 hemiarches - group 1) or diastema (17 hemiarches - group 2). Clinical (plaque index, probing depth, gingival bleeding index, height of the gingival margin, clinical attachment loss and gingival clefts) and radiographic (crest height, bone height and bone-crest discrepancy) parameters of the distal surfaces of canines and mesial surfaces of premolars were evaluated. Group 1 had worse results when compared to the control group for the levels of plaque in canines and premolars and for probing depth in canines (distal and mean) and in premolars (lingual and mean), as well as increasing tendency of clinical attachment loss (lingual and mean) in premolars. Plaque level in canines in group 1 was also significantly higher than in group 2. There was no difference between group 2 and the control group. The lack of proximal contact between canines and second premolars did not significantly affect their periodontal characteristics.

Introduction: This study aimed to simulate the different positions of the hyrax appliance expander screw and evaluate tooth displacement and the stress distribution standard on the periodontal ligament using the finite element method., Methods: Part of the maxilla with anchorage teeth, periodontal ligament, midpalatal suture, and the hyrax appliance was modeled, and finite element method models were created to simulate 6 different screw positions. There were 2 vertical positions at distances of 20 mm and 15 mm from the occlusal plane. Another position was anteroposterior, the center of the screw placed between and equidistant from the mesial face of the first molar and the distal face of the first premolar, aligned to the center of the crown of the first molar, with the anterior edge of the screw aligned to the distal face of the first molar. A 1 mm activation of the expander screw was simulated. The displacement (total, vertical, and buccolingual) and the stress distribution on the periodontal ligament of supporting teeth in each model were registered., Results: The model simulating the expander screw in a more occlusal and anterior position presented higher displacement values and higher stress concentration, followed by the model with the screw in a more posterior but same vertical position. With the exception of the first premolar, the teeth presented cervical-apical displacement in the vestibular face and apical-cervical displacement in palatal faces. This displacement is compatible with the vestibular inclination associated with the activation of the expander screw. The first premolar presented an atypical tendency for the mesial and lingual displacement of the vestibular surface and counterclockwise rotation., Conclusions: The supporting teeth presented a tendency for vestibular crown displacement and lingual root displacement associated with compression areas in the vestibular-cervical region and tensile strength in the linguoapical region. Placing the expander screw in a more occlusal and anterior position generated more mechanical stress transfer, resulting in greater dental displacement., (Copyright © 2021 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: Our objective was to evaluate the stress and deformation distribution patterns on the maxillary bone structure using the finite element method by simulation of different vertical and anteroposterior positions of the expansion screw on the hyrax expander appliance., Methods: Part of the maxilla with anchorage teeth, midpalatal suture, and the hyrax appliance were modeled, and 6 distinct finite element method models were created to simulate different positions of the expansion screw. There were 2 vertical positions at distances of 20 and 15 mm from the occlusal plane. Another 3 positions were anteroposterior, with the center of the screw placed between and equidistant from the mesial face of the first molar and the distal face of the first premolar, aligned to the center of the crown of the first molar, and the anterior edge of the screw aligned to the distal face of the first molar. The initial activations of the expanders were simulated, and the stress distributions on the maxilla in each model were registered., Results: The stress was concentrated in the anterior region of the models, close to the incisive foramen, dissipating through the palate in the posterior and lateral orientations, in the direction of the pterygoid pillar, diverting from the midpalatal suture region. When the expander screw was simulated closer to the occlusal plane and in a more anterior position, more stress was located around the incisive foramen and distributed through the midpalatal suture to its posterior portion. More posterior positions resulted in concentrated stress around the pterygoid pillars. At all simulations, the midpalatal suture showed a V-shaped expansion, with the vertex superior in the coronal view and posterior in the axial view., Conclusions: Different positions of the expander screw interfered with stress intensity and distribution patterns. When the expansion screw was simulated in a more occlusal and anterior position, it was more efficient to transfer the mechanical effects from the appliance to the bone structures., (Copyright © 2018 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: In this study, we aimed to evaluate the influence of clinical experience and the type of tooth (incisors, canines, and premolars) on the vertical accuracy of bracket placement with the Boone gauge., Methods: For this analysis, 4 groups were defined. Group 1 was composed of undergraduate students from the dental school with no previous experience in bonding orthodontic attachments; group 2 was composed of graduate students in the dental school; group 3 consisted of orthodontists with a maximum of 5 years of clinical experience; and group 4 comprised orthodontists with more than 5 years of clinical experience. Each group included 6 participants. A typodont was simulated with a Class I crowded malocclusion that reproduced the same occlusal characteristics for all groups to be bonded. All participants were instructed to bond 0.022 × 0.028-in edgewise brackets on the labial surfaces of the maxillary and mandibular incisors, canines, and premolars at a height of 4 mm from the incisal edge or the labial cusp tip. After each bonding procedure, all teeth were photographed after being removed from the typodont and positioned in a stabilizing device adapted to a camera stand., Results: The analyses of the variations showed that group 1 had the closest mean to 4 mm. However, this group also showed the greatest variance (0.433) (P <0.001). The smallest variations were observed in group 2 (variance, 0.093), followed by group 4 (variance, 0.094). The comparison of the means obtained in the groups of teeth at 4 mm demonstrated that the incisors showed a statistically significant difference (P <0.001), whereas canines (P = 0.133) and premolars (P = 0.913) did not., Conclusions: Operators are prone to fail in the placement of orthodontic attachments with the Boone gauge, despite their clinical experience in orthodontics. In the comparison of the groups of teeth, the incisors showed a statistically significant difference in relation to the height suggested for bracket placement with the Boone gauge., (Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine the effect of field of view (FOV) size on gray values in cone beam computed tomography (CBCT) and multislice computed tomography (MSCT) images., Material and Methods: A phantom made up of 3 cylinders containing distilled water, plaster, and motor oil was constructed and inserted into an acrylic cylinder filled with distilled water. The phantom was scanned with a CBCT and MSCT device using 3 FOV sizes. Gray value of each material was evaluated in 40 axial slices, and the comparison between the results obtained with the same FOV size was made., Results: In CBCT examinations, there was significant difference between the gray values of different FOVs for the 3 materials. In the MSCT, there was significant difference for the oil. Gray values showed significant difference between the CBCT and MSCT examinations for the 3 materials in the 3 different FOV sizes., Conclusions: Gray values determined in CBCT images are significantly influenced by the FOV size. Although the gray values obtained in MSCT have shown statistically significant differences between some acquisitions, the analysis of those differences seems to indicate low clinical relevance.

Cone beam computed tomography (CBCT) has often been used to determine the quality of craniofacial bone structures through the determination of mineral density, which is based on gray scales of the images obtained. However, there is no consensus regarding the accuracy of the determination of the gray scales in these exams. This study aims to provide a literature review concerning the reliability of CBCT to determine bone mineral density. The gray values obtained with CBCT show a linear relationship with the attenuation coefficients of the materials, Hounsfield Units values obtained with medical computed tomography, and density values from dual energy X-ray absorciometry. However, errors are expected when CBCT images are used to define the quality of the scanned structures because these images show inconsistencies and arbitrariness in the gray values, particularly when related to abrupt change in the density of the object, X-ray beam hardening effect, scattered radiation, projection data discontinuity-related effect, differences between CBCT devices, changes in the volume of the field of view (FOV), and changes in the relationships of size and position between the FOV and the object evaluated. A few methods of mathematical correction of the gray scales in CBCT have been proposed; however, they do not generate consistent values that are independent of the devices and their configurations or of the scanned objects. Thus, CBCT should not be considered the examination of choice for the determination of bone and soft tissue mineral density at the current stage, particularly when values obtained are to be compared to predetermined standard values. Comparisons between symmetrically positioned structures inside the FOV and in relation to the exomass of the object, as it occurs with the right and left sides of the skull, seem to be viable because the effects on the gray scale in the regions of interest are the same.

Objective: To evaluate, in vitro, the shear bond strength presented by three brands of polycrystalline ceramic brackets and one brand of metallic bracket; verify the adhesive remnant index (ARI) after the tests, and analyze, through scanning electron microscopy (SEM) the enamel surface topography after debonding, detecting the release of mineral particles., Methods: Sixty bovine lower incisors were used. Three ceramic brackets (Allure®, InVu®, and Clarity®) and one metallic bracket (Geneus®) were bonded with Transbond XT®. Kruskal-Wallis's test (significance level set at 5%) was applied to the results of shear bond and ARI. Mann Whitney's test was performed to compare the pairs of brackets in relation to their ARI. Brown-Forsythe's test (significance level set at 5%) was applied to the results of enamel chemical composition. Comparisons between groups were made with Games-Howell's and the Post-hoc tests., Results: No statistically significant difference was observed in relation to the shear bond strength loads. Clarity® brackets were the most affected in relation to the surface topography and to the release of mineral particles of enamel (calcium ions)., Conclusions: With regard to the ARI, there was a prevalence of score 4 (40.4%). As for enamel surface topography, the Geneus® bracket was the only one which did not show superficial tissue loss. The InVu® and Clarity® ones showed cohesive fractures in 33.3% and the Allure® in 50%, the latter being the one that presented most fractures during removal.

Objectives: In the present study, we developed new software for quantitative analysis of cervical vertebrae maturation, and we evaluated its applicability through a multinomial logistic regression model (MLRM)., Methods: Digitized images of the bodies of the second (C2), third (C3) and fourth (C4) cervical vertebrae were analysed in cephalometric radiographs of 236 subjects (116 boys and 120 girls) by using a software developed for digitized vertebrae analysis. The sample was initially distributed into 11 categories according to the Fishman's skeletal maturity indicators and were then grouped into four stages for quantitative cervical maturational changes (QCMC) analysis (QCMC I, II, III and IV). Seven variables of interest were measured and analysed to identify morphologic alterations of the vertebral bodies in each QCMC category., Results: Statistically significant differences (p < 0.05) were observed among all QCMC categories for the variables analysed. The MLRM used to calculate the probability that an individual belonged to each of the four cervical vertebrae maturation categories was constructed by taking into account gender, chronological age and four variables determined by digitized vertebrae analysis (Ang&#95;C3, MP&#95;C3, MP&#95;C4 and SP&#95;C4). The MLRM presented a predictability of 81.4%. The weighted κ test showed almost perfect agreement (κ = 0.832) between the categories defined initially by the method of Fishman and those allocated by the MLRM., Conclusions: Significant alterations in the morphologies of the C2, C3 and C4 vertebral bodies that were analysed through the digitized vertebrae analysis software occur during the different stages of skeletal maturation. The model that combines the four parameters measured on the vertebral bodies, the age and the gender showed an excellent prediction.

Objective: Development of a new device to be coupled to light-curing units for bonding orthodontic brackets and accessories, and test its efficacy in an in vitro mechanical trial. The inner surface of the device is mirrored and is based on physical concepts of light refraction and reflection. The main advantage of such device is the reduced clinical time needed for bonding and the low possibility of contamination during the process., Methods: One hundred and twenty specimens were used for testing the shear bond strength of brackets bonded with the device. The Adhesive Remnant Index (ARI) was also determined. The sample was divided into 2 groups. In group 1 a halogen light-curing unit was used while in group 2 a led light-curing unit was used. Each group was then subdivided. In subgroups H1 and L1, a conventional light guide rod was used while in subgroups H2 and L2 bonding was performed with the mirrored device coupled to the tip of the guide light rod., Results: The values obtained for the shear bond strength and the ARI in the subgroups were compared. Results showed that there was no statistically significant difference for the shear strength (p > 0.05) and the ARI (p > 0.05) between the subgroups., Conclusions: The tests of mechanical trials and the ARI analysis showed that the new device fulfilled the requirements for bonding orthodontic accessories, and that the time for bonding was reduced to half, being necessary only one light exposure.

Introduction: A wide variety of orthodontic wires made of different alloys is available to be used in orthodontic practice and may produce different clinical responses during tooth movement., Objective: This research evaluated the alignment and leveling of lower dental arches after the use of three types of orthodontic wires., Methods: A sample of 36 patients was randomly divided into 3 groups: stainless steel, multistranded steel and superelastic nickel-titanium, according to the first leveling arches used. In order to observe differences in tooth position and axial inclination of the lower incisors, all patients had lateral cephalometric radiographs taken before the insertion of the first arches and 2 months later. The irregularity index and the curve of Spee were measured, compared between groups and considered influential on the proclination of incisors during the initial phase of alignment and leveling. The Reflex microscope was used to measure the irregularity index, whereas the ANOVA analysis of variance was used to verify differences between groups with regard to the degree of dental alignment and leveling., Results: There were significant differences between groups only at T2 for the irregularity index., Conclusions: The NiTi and multistranded steel wires showed greater aligning capacity when compared with stainless steel wires.

Background: The present study aimed to determine and compare the anteroposterior position of the condyle in the mandibular fossa between groups of asymptomatic subjects with normal occlusion and asymptomatic subjects with Class I, Class II Division 1, and Class III malocclusions., Material and Methods: Thirty persons with normal occlusion, 30 with Class I malocclusion, 30 with Class II Division 1, and 30 with Class III had computed tomography scans of their temporomandibular joints. The anterior joint space/posterior joint space (AJS/PJS) ratio was determined for the right and left joints. The paired t test was used to analyze the AJS/PJS ratio between both sides for each group. The ANOVA test was applied to verify the differences between the groups for the measurements of the right and left sides. In case the ANOVA test confirmed significance, the Dunnett's t test was performed to compare the groups of malocclusion with that of normal occlusion., Results: The paired t test between the AJS/PJS relationships in the right and left sides showed the following p values: Class I (0.168), Class II Division 1 (0.662), Class III (0.991), and normal occlusion (0.390). The ANOVA test showed a p value of 0.445 for the comparisons of the right side and 0.040 for the left side. The Dunnett's t test demonstrated a statistically significant difference between the Class II group and the normal occlusion group (p value of 0.026) in the joints of the left side., Conclusions: Bilateral symmetry and lack of condyle centralization were common characteristics among all groups. The greatest condylar decentralization was observed in the Class II group, whereas the least condylar decentralization was found in the normal occlusion group.

Introduction: Ninety five percent of orthodontic patients routinely report pain, due to alterations in the periodontal ligament and surrounding soft tissues, with intensity and prevalence varying according to age., Objective: This study aimed to assess toothache and buccal mucosal pain in adults and children during two initial phases of the orthodontic treatment., Methods: The intensity of toothache and buccal mucosal pain reported by 20 patients, 10 children (11-13 years) and 10 adults (18-37 years) was recorded with the aid of a Visual Analog Scale (VAS), during 14 days--7 days with bonded brackets only and 7 days with the initial archwire inserted., Results: There was no significant difference in pain intensity among adults and children. After bracket bonding, 50% of the children and 70% of the adults reported pain. 70% of both groups reported pain after initial archwire insertion. While adults reported constant, low intensity, buccal mucosal pain, the children showed great variation of pain intensity, but with a trend towards decreasing pain during the assessment period. After initial archwire insertion the peaks of toothache intensity and prevalence occurred 24 hours in children and 48 hours in adults., Conclusions: In general, children reported pain less frequently than adults did, though with greater intensity.

Introduction: Patients usually experience pain during orthodontic treatment. This fact can affect cooperation and the development of treatment. Reporting pain during treatment seems to be influenced by emotional aspects such as the patient's motivation., Objective: To assess the relationship between patient's motivation and the intensity of reported pain during two stages of treatment., Methods: Twenty males (11-37 years old) answered a questionnaire divided into five categories regarding their motivation towards treatment. The subjects were studied for 14 days (7 days with bonded brackets and 7 days with the initial arch inserted) and the intensity of pain was evaluated on a daily basis. All the issues, including the intensity of pain, were measured through the visual analog scale (VAS)., Results: The VAS-associated questionnaire proved to have good temporal reliability and reasonable internal consistency, being that the "perceived severity" domain had the greatest, although not significant (p = 0.196) correlation with pain intensity. Only the question asking the patients if they thought that their teeth were too uneven showed a positive correlation with pain intensity (p = 0.048)., Conclusions: The results seem to indicate that the five categories related to treatment motivation cannot be used to predict discomfort during treatment. In addition, patients who think their teeth are too uneven may experience more severe pain due to greater force application after insertion of the initial arch.

Introduction: The diagnosis of apical root resorption is usually based on routine radiographs. However, these methods are limited because the images reflect the superimposition of the whole root structure and can lead to underestimation of the extent of apical root resorption. In this study, we aimed to determine the lengths of the labial and lingual surfaces of incisors with apical root resorption and compare them with the longest radicular length obtained on sagittal images of cone-beam computed tomography, and to create a qualitative visual scale of the different patterns of apical root resorption., Methods: Eighty-two incisors with apical root resorption from 25 patients had their labial and lingual root surfaces and the longest radicular lengths determined in the sagittal plane and compared. Five orthodontists, at 2 times, classified the images of each incisor according to a visual scale developed by the authors., Results: There was no significant difference between the labial and lingual surfaces; however, the longest radicular length was significantly greater than the shortest surface length. The visual scale showed intraobserver agreement of 0.615 and interobserver agreements of 0.74 and 0.52 at both times, respectively., Conclusions: The difference between the longest and shortest root lengths suggests that radiographic superimposition underestimates the extent of the resorption lesion. The proposed visual scale showed a frequency of agreement above 65% and a coefficient of reproducibility varying from moderate to substantial., (Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Background: Orthodontic force application to the teeth is responsible for a series of biological responses in the bone and dentin, which lead to some alterations of the mineral density of the tissues. Our objective was determine, through cone-beam computed tomography (CBCT), the mineral density of the apical third of the roots of the upper central incisors and of the periapical bone portion surrounding these teeth, in patients submitted to orthodontic treated and untreated individuals., Material/methods: 30 untreated individuals and 15 treated ones (treatment cessation at least 1 year before the study) underwent CBCT. Mineral density was assessed in the apical third of the root of the upper central incisors and in the alveolar bone in the periapical region of these teeth. In order to reduce CBCT-related mineral density variability, we standardized the cone-beam tomography device, the image-acquisition settings and the field of view positioning and size. Student's t test was used for the analyses., Results: bone mineral density (BMD) and root mineral density (RMD), in Hounsfield Units, were 674.84 and 1282.26 for the untreated group and 630.28 and 1370.29 for the treated group, respectively. The differences between the group means were statistically significant for RMD (p<0.05)., Conclusions: untreated individuals had a significant lower mean RMD in comparison with those submitted to orthodontic treatment.

Objective: To identify and review the literature regarding the reliability of cervical vertebrae maturation (CVM) staging to predict the pubertal spurt., Materials and Methods: The selection criteria included cross-sectional and longitudinal descriptive studies in humans that evaluated qualitatively or quantitatively the accuracy and reproducibility of the CVM method on lateral cephalometric radiographs, as well as the correlation with a standard method established by hand-wrist radiographs., Results: The searches retrieved 343 unique citations. Twenty-three studies met the inclusion criteria. Six articles had moderate to high scores, while 17 of 23 had low scores. Analysis also showed a moderate to high statistically significant correlation between CVM and hand-wrist maturation methods. There was a moderate to high reproducibility of the CVM method, and only one specific study investigated the accuracy of the CVM index in detecting peak pubertal growth., Conclusions: This systematic review has shown that the studies on CVM method for radiographic assessment of skeletal maturation stages suffer from serious methodological failures. Better-designed studies with adequate accuracy, reproducibility, and correlation analysis, including studies with appropriate sensitivity-specificity analysis, should be performed.

Purpose: This study determined the relationship between tooth-size reduction, agenesis and the occurrence of palatally displaced canines (PDCs). Emphasis was given to the association between anomalous and/or absent maxillary lateral incisors and PDCs., Methods: Pretreatment records of 66 consecutively treated orthodontic patients with PDCs and 66 controls were evaluated. Maximum mesiodistal (M-D) crown diameters were recorded for all teeth, except the second and third molars. Tooth agenesis was evaluated by radiographs. The level of significance was P<.05., Results: The occurrence of agenesis in the PDC sample was approximately 26%. Congenital absence of the lateral incisors was noted in 2 male subjects (3%). The occurrence of small lateral incisors was approximately 39%., Conclusions: Female subjects with palatally displaced canines showed significant overall reductions of the maximum mesiodistal widths for all teeth, except the mandibular first molars. Female PDC subjects with 1 or more congenitally absent teeth showed significant reductions in M-D diameters of the maxillary left lateral incisors, mandibular second premolars, and first molars in relation to the female PDC subjects with no absent teeth. The association between tooth agenesis and PDCs was not observed. There also was no significant association between adjacent anomalous and/or absent maxillary lateral incisors and PDCs.

Supernumerary teeth are an infrequent developmental anomaly that can appear in any area of the dental arch and can affect any dental organ. Multiple supernumerary teeth, or hyperdontia, is rare in people with no other associated diseases or syndromes. Conditions commonly associated with hyperdontia include cleft lip and palate, trichorhinophalangeal syndrome, cleidocranial dysplasia, and Gardner's syndrome. A black girl, aged 11 years 8 months, came for consultation; radiographs showed 81 teeth: 18 deciduous, 32 permanent, and 31 supernumerary. The main concern initially was to determine whether she was syndromic, and she was referred to a geneticist. G banding analysis showed pericentric inversion of chromosome 9; the chromosome formula was 46, XX, inv (9) (p13q21). Orthodontic treatment for this patient will be a clinical challenge because of the great number of teeth to be extracted and the alterations in the shapes of the teeth. Treatment goals should be established by a multidisciplinary team, where oral surgeon, orthodontist, periodontist, and prosthodontist come together to solve a medical and dental puzzle, eliminating the pieces that do not fit and searching for new ones to obtain an occlusion that will give the patient physiologic conditions of normality and esthetic satisfaction., (Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Introduction: Pain, a common experience reported by orthodontic patients, has its intensity assessed with the help of subjective scales, which have a limited and disputable value. Such unpleasant experience, which may raise stress levels, is reflected by an increase in the salivary concentration of alpha-amylase., Objective: Assess the correlation between the salivary levels of alpha-amylase and pain intensity reported by patients during orthodontic treatment., Patients: Twenty male patients (11-37 years of age) were assessed daily, before treatment, after bracket bonding, and after initial arch wire insertion., Design: Saliva was sampled for alpha-amylase analysis, and pain intensity was measured with the visual analog scale., Results: There was no correlation between alpha-amylase concentrations in the saliva and pain intensity, although the patients had a significant and progressive increase of alpha-amylase levels during the assessment period., Conclusions: The findings may reflect the psychological stress caused by the presence and activation of the fixed appliance., (Wiley Periodicals, Inc.)

Introduction: The purpose of this study was to investigate the condyle-fossa relationship, the position of the condyles in their respective mandibular fossae, and the dimensional and positional symmetries between the right and left condyles in a sample with normal occlusion., Methods: Thirty subjects from 15 to 32 years of age with normal occlusion had computed tomography scans of their temporomandibular joints. The images obtained from the axial slices were evaluated for possible asymmetries in size and position between the condylar processes. The images obtained from the sagittal slices were used to assess the depth of the mandibular fossa, the condyle-fossa relationship, and the centralization of the condyles in their respective mandibular fossae. Paired Student t tests were applied, and Pearson product moment correlations were determined after measurements on both sides were obtained., Results: The largest mediolateral diameter of the mandibular condylar processes (P = 0.022) and the posterior joint spaces (P = 0.048) showed statistically significant differences between the right and left sides. Statistically significant (P <0.05) anterior positioning of the condyles (noncentralized position) was observed., Conclusions: No singular characteristic in the temporomandibular joints of the normal occlusion group was verified. The largest mediolateral diameter of the mandibular condylar processes and the posterior joint spaces showed statistically significant differences between the right and left sides. Evaluation of the position of the condyles in their respective mandibular fossae showed noncentralized positioning for the right and left sides., (Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Background: Pain, a common experience reported by patients under orthodontic treatment, results from force application to the teeth and trauma caused by attrition of brackets and wires against the underlying oral mucosa. The main protection of the mucosa is secretory immunoglobulin A (sIgA), which may play a fundamental role in integrity maintenance and whose production may be reduced as a result of the stress of orthodontic treatment. The aim of this study was to assess sIgA levels in the saliva and their correlation with oral pain intensity in adults and children after the installation of fixed orthodontic appliances., Material/methods: Twenty patients (10 children, age 11-13 years; 10 adults, age 18-37 years) were assessed before treatment, after bracket bonding, and after initial arch wire insertion. Saliva was sampled for sIgA analysis, and oral pain was assessed through a visual analog scale., Results: Although there was a trend toward reduction of the salivary sIgA levels during the initial arch phase in the children, and during the bonding and initial arch phases in the adults, this finding was not significant., Conclusions: There was a trend toward a negative correlation of oral pain intensity and salivary sIgA levels in the children, which may indicate the importance of sIgA for oral protection during orthodontic treatment, interfering with the pain experienced by the patients.

Introduction: Ceramic brackets are chemically inert in the oral cavity, whereas polycarbonate and polyoxymethylene brackets can degrade and release bisphenol-A and formaldehyde, respectively. More reliable tests are needed to assess the potential toxicity of these materials. In addition to traditional cytotoxicity tests, the study of nitric oxide (NO) cellular production stimulated by a specific material has been shown to be a reliable tool for evaluating cytotoxic potential. The purpose of this study was to assess, with esthetic brackets, cellular viability by 3,(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide assay (Sigma, St. Louis, Mo) in the macrophage cell line J774 stimulated with interferon gamma. Interferon gamma is a key cytokine in the activation of macrophages, plays an important role in immunologic processes, and also quantifies NO production by these macrophages., Methods: Well plates were seeded with 2 x 104 J774 cells per well, in a volume of 100 microL, resuspended in Roswell Park Memorial Institute Supplemented Medium 1640. The macrophage cell line J774 was stimulated with interferon gamma. Ceramic, polycarbonate, and polyoxymethylene brackets were added and kept in the culture for 24, 48, or 72 hours in 5% carbon dioxide at 37 degrees C; the control samples did not include brackets. At the end of each incubation period, the supernatant was collected for posterior NO quantification, and the cells were evaluated for cytotoxicity., Results: Cellular viability in all groups was higher at 72 hours than at 24 hours. The final means in the bracket groups did not show significant differences compared with the control group. NO production was significantly greater in all groups at the final time than at the initial time. However, the brackets with the interferon gamma stimulation did not result in greater NO production than did the cells in the control group., (Copyright (c) 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Introduction: Studies show that ceramic brackets are chemically inert in the oral cavity, whereas polycarbonate and polyoxymethylene brackets can degrade, releasing bisphenol-A and formaldehyde, respectively. In addition to the traditional cytotoxicity tests, the study of nitric oxide cellular production stimulated by a specific material has been shown to be a reliable tool for evaluating its cytotoxic potential., Methods: We aimed to assess cellular viability by MTT (Sigma, St. Louis, Mo): 3,(4,5-dimethylthiazol-2-yl)-2,5diphenyl tetrazolium bromide assay in a murine macrophage cell line J774 with esthetic brackets and quantify nitric oxide production by these macrophages. Cell cultures were evaluated at 3 times: 24, 48, and 72 hours., Results: Cellular viability in all groups was higher at 72 hours compared with 24 hours. This increase was significant in the control and ceramic brackets groups. Final means in the bracket groups showed no significant differences compared with the control group. Nitric oxide production was significantly greater in all groups at final time. There was no significant difference between the final means of the bracket groups and the control group, although polyoxymethylene brackets showed significantly greater means at 24 and 48 hours., Conclusions: Final means in the bracket groups showed no significant differences compared with the control group.

Potassium diclofenac is a potent nonsteroidal anti-inflammatory drug (NSAID) and COX isoforms (COX-1 and COX-2) inhibitor. Quantitative analysis of birefringence with polarized light microscopy is a useful method to investigate the macromolecular orientation and organization of collagen fibers in connective tissues. The aim of this research was to analyze the collagen structure and maturation in bone formed after potassium diclofenac administration, during first molar orthodontic movement. Sixty Wistar rats were divided in two equal groups (N = 30): control (C) and potassium diclofenac (PD). The animals in Group C received 0.9% saline solution and the PD group received potassium diclofenac Cataflam (5 mg/kg). Animals were sacrificed 3, 7, or 14 days after a NiTi unilateral closed-coil spring was stretched between the upper right first molar and the incisors. The first molar area was fixed, decalcified, and histologically processed using picrosirius pigment. The collagen birefringence of bone turnover was analyzed by phase retardation. Two-way ANOVA and Tukey's test showed that optical retardation was influenced by time and treatment. There was increase in the collagen organization over time. On the third day, the C group showed better collagen organization than the PD group. Potassium diclofenac interfered in collagen maturation, reducing fibril organization in the initial phase of orthodontic movement., (2009 Wiley-Liss, Inc.)

Background: This study verifies clinical results of using a polydioxanone (PDS) tent without a guided tissue regeneration (GTR) membrane for root coverage., Methods: Forty-nine gingival recessions (in 16 patients) were treated with a PDS tent inserted under the coronally positioned gingival flap. The recession level (RL), probing depth (PD), and keratinized mucosa width (KMW) were registered. Statistical analysis was performed with the Wilcoxon test., Results: In 48 cases, there was a significant reduction in the RL (2.55 +/- 1.11 mm on day 0 and 0.34 +/- 0.65 mm on day 120; P = 0.0001). PD showed the same values at the beginning and end of treatment in 47 cases (0.99 +/- 0.71 mm on days 0 and 120; z = 0.000). There was a significant increase of KMW in 46 cases (2.38 +/- 0.76 mm on day 0 and 3.18 +/- 0.90 mm on day 120; P = 0.0001)., Conclusions: The association of the PDS tent without the GTR membrane to a coronal sliding flap for root coverage of Miller Class I and II gingival recessions allows root coverage, gain of attachment level, and an increase of keratinized mucosa. For root coverage, it is not necessary to use the GTR membrane associated to the PDS tent, thereby reducing surgical costs. Future studies should be conducted to assess the sole performance of the PDS as an alternative method to a connective tissue graft and coronal sliding flap, thus decreasing risks and post-surgery discomfort.

Introduction: The aims of this study were to correlate the clinical and radiographic stability of titanium miniscrews when used as orthodontic anchorage for maxillary canine retraction and to assess bone quality., Methods: Thirty titanium miniscrews were placed in 15 consecutive patients (8 male, 7 female; age range, 12 years 5 months-32 years 11 months) as orthodontic anchorage. Orthodontic loads were applied immediately after miniscrew placement (T1) with a nickel-titanium closing coil spring. The initial estimated load was 200 g. The bone quality in each region of interest was determined by multi-slice computed tomography., Results: Bone mineral density (BMD) values ranged from 167 HU to 660.80 HU (mean, 420.63 HU). The specific regions had a mean close to the maximum value of a previously established scale for the posterior region of the maxilla (0-500 HU). The paired t test showed a statistically significant difference (P = 0.450) when the means of the differences between the right and left sides were compared. Twelve of the 15 subjects had significantly greater maxillary BMD on the right side. Linear regression also showed a low correlation between the 2 sides (P = 0.097). Clinically, the success index was 100%. Although 2 miniscrews were removed from 1 patient because of severe gingival inflammation with purulent secretion, none of the 28 remaining miniscrews showed any mobility after 90 days (T2). Comparisons of the means at T1 and T2 showed no statistically significant differences in these distances: between nasion and the miniscrew head, between orbitale and the miniscrew head, and between nasion and orbitale, assessed through cephalometric tracings made on lateral oblique radiographs (45 degrees ), pointing to the stability of the 28 miniscrews during the 90-day observation period. BMD values of all subjects were within the normal range of an established scale, and even close to maximum values., Conclusions: The regions between the maxillary second premolars and first molars, and mesial to the maxillary second premolars, are safe as far as bone quality is concerned for miniscrew placement during the first 90 days of canine distalization. A good surgical technique and appropriate planning for miniscrew placement, inflammation control, and adequate oral hygiene are fundamental to the success of this new anchorage system during maxillary canine distalization.

Introduction: The purpose of this study was to investigate the condyle-fossa relationship, the concentric position of the condyles, and the dimensional and positional symmetries between the right and left condyles in Class II Division 1 and Class III malocclusion samples., Methods: Thirty subjects from 12 to 38 years of age with Class II Division 1 malocclusion and 16 subjects from 13 to 41 years of age with Class III malocclusion had computed tomography of the temporomandibular joints. The images obtained from the axial slices were evaluated for possible asymmetries in size and position between the condylar processes associated with these malocclusions. The images obtained from the sagittal slices were used to assess the depth of the mandibular fossa, the condyle-fossa relationship, and the concentric position of the condyles associated with these malocclusions. Paired Student t tests were applied, and Pearson product moment correlations were determined after measurements on both sides were obtained., Results: In the Class II Division 1 sample, the distance of condylar process/midsagittal plane (P = 0.019) and posterior joint space (P = 0.049) showed statistically significant differences between the right and left sides. In the Class III sample, there was no statistically significant difference between sides. Statistically significant (P <0.05) anterior positioning of the condyles was observed (nonconcentric positioning) in both the Class II Division 1 group and the Class III group., Conclusions: In the Class II Division 1 malocclusion sample, the distance of condylar process/midsagittal plane and posterior articular space had statistically significant differences between the right and left sides. In the Class III sample, there was no statistically significant difference between sides. Evaluation of the concentric position of the condyles in their mandibular fossae showed nonconcentric positioning for the right and left sides in both the Class II and Class III malocclusion groups.

Introduction: The purpose of this study was to investigate the condyle-fossa relationship, the concentric position of the condyles, and the dimensional and positional symmetries between the right and left condyles in subjects with Class I malocclusion., Methods: Thirty subjects from 13 to 30 years of age with Class I malocclusion had computed tomography imaging of the temporomandibular joints. The images obtained from axial slices were evaluated for possible asymmetries in size and position between the condylar processes associated with this malocclusion. The images obtained from sagittal slices were used to assess the depth of the mandibular fossa, the condyle-fossa relationship, and the concentric position of the condyles of this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations were determined after measurements on both sides were obtained., Results: We found no statistically significant asymmetries between the condylar processes in this sample. No statistically significant asymmetries were found in the mandibular fossa depth, the anterior joint space, and the superior joint space. The posterior joint space showed statistically significant asymmetry (P <0.05) between the right and left sides. Statistically significant (P <0.05) anterior positioning of the condyles was observed (nonconcentric positioning)., Conclusions: Only the posterior articular space had a statistically significant difference between the right and left sides. There was a higher mean for posterior articular space on the right temporomandibular joint. Evaluation of the concentric position of the condyles in their mandibular fossae showed nonconcentric positioning for the 2 sides.

A 68-year-old woman was treated with an autogenous particulated bone graft from the anterior part of the mandible to elevate the right maxillary sinus floor, which was next to the alveolar ridge of an edentulous area, to facilitate dental implant placement. A rigid plate for anchorage was placed into the zygomatic bone. The maxillary right canine and the premolars were moved distally 6 months after the implant was placed and osteointegration of the bone graft had occurred. The Class II relationship was corrected. After tooth movement, the patient underwent multislice computed tomography to determine the mineral density of the bone graft and compare it with the opposite side of the maxilla. The mineral density showed values above normal for the posterior segment of the maxilla. Although the patient was taking bisphosphonate for treatment of osteoporosis, no related complications were noted during treatment.

Onychophagia, or nailbiting, is a common oral habit, observed in both children and adults. The etiologies suggested for nailbiting include anxiety, stress, loneliness, imitation of other family member, heredity, inactivity, transference from a thumb-sucking habit, and poorly manicured nails. Treatment should be directed at the causes; punishment, ridicule, nagging and threats, and application of bitter-tasting commercial preparations on the nail are a variety of reminders, but are not appropriate approaches to treatment. The key to success is the nailbiter's consent and cooperation.

In dental research, dorsoventral cephalometric radiography is often used to assess skull growth and dental movement in rat models. To ensure that images can be reproduced, radiographers must use a cephalostat to maintain the rat's head in a consistent position across imaging sessions. The authors describe a positioning device they designed that connects easily to a standard dental X-ray machine. The device enabled researchers to position rats repeatedly for radiographic imaging with very little variation.

This article discusses the adaptive alterations of the temporomandibular joints of a boy, aged 8 years 5 months, who underwent correction of a unilateral posterior crossbite. The shape and position of the articular structures, imaged by helicoidal computed tomography at the end of the expansion period and 7 months after treatment, showed a tendency toward condylar centralization and articular symmetry.

A 32-year-old white man presented for orthodontic treatment with the chief complaint of mandibular prognathism; he was later found to have acromegaly. General information about pituitary adenomas, specifically growth hormone adenomas, is given, and treatment options are discussed.

This study was designed for the identification of possible and distinct abilities for behavioral recovery after prenatal cerebral damage. We adopted an interesting tool for promotion of cell's death. Due to the fact that neuroblastic cells and early postmitotic neurons on the beginning of differentiation are particularly sensible for the promotion of apoptosis, we used a low whole-body dose of X radiation on pregnant female mice on E16 (sixteenth gestational day) to promote damage on specific cerebral areas of the progeny, given that the pattern of cerebral neurogenesis is not homogeneous. The morphological results were previously described by our team. Here we noticed that the recovery of behavioral functions after prenatal damage seems to be related to specific factors of local cortical circuitry organization. The deficits found on visual navigation and working memory contrast with the recovery of primary visual functions and also with reference memory, where the mice have a delay on acquisition of learning but get it. As a conclusion we reasoning that changes on laminar organization on frontal cortex as well as the inter hemispheric cortical integration through the corpus callosum could promote relatively fixed cognitive dysfunctions, as those observed on performances that require strategies for navigation (decision making) and working memory, with consequences also observed on the subsequent learning.

Thirty persons with Class II Division 1 subdivision malocclusions, ranging in age from 12 years 8 months to 42 years, underwent computed tomography of the temporomandibular joints. The images obtained from sagittal slices were used to assess the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, the condyle-fossa relationship, and the concentric position of the condyles associated with this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations (r) were determined after measurements on both Class I and Class II sides were obtained. No statistically significant asymmetries were found in the depth of the mandibular fossa, the angulation of the posterior wall of the articular tubercle, or the condyle-fossa relationship. However, a statistically significant (P <.05) anterior positioning of the condyles was observed.

Thirty persons ranging from 12 years 8 months to 42 years of age with Class II Division 1 subdivision malocclusions underwent computed tomography of the temporomandibular joints. The images obtained from axial slices were evaluated for possible asymmetries in size and position that may exist between the condylar processes associated with this malocclusion. Paired Student t tests were applied, and Pearson product moment correlations were determined after measurements on both Class I and Class II sides were obtained. The results of this study showed no statistically significant asymmetries between the condylar processes evaluated in this sample.

Studies using neonatal surgical lesions to reduce the target area of the retina have supported the idea that developing axons show only a limited specificity in their targeting. This investigation tested whether retinogeniculate axons adjust for partial target depletion by repositioning of axons. We used adult Swiss mice exposed to gamma rays at the time when layer IV cells are generated in the ventricular zone (16 days of gestation). Nissl-stained brain sections were used for histological analyses in thalamus and cortex. Retinal ganglion cells were backfilled from the optic tract with horseradish peroxidase. Intraocular injections of horseradish peroxidase were used to study the retinal projections. In the posterior cortex there was a nearly complete absence of layer IV. The irradiated animals showed a 75% reduction of the dorsal lateral geniculate nucleus. The ventral division, superior colliculus, and other visually related nuclei were not affected. The loss in the ganglion cells (15.7%) was significant but clearly smaller than that observed in the dorsal lateral geniculate nucleus (75%). Therefore, the shrinkage of the dorsal lateral geniculate nucleus led to a reduction in the area available for retinal projections. Despite partial target loss, pattern of retinal projections did not differ from that of the controls. The effect on the dorsal lateral geniculate nucleus is discussed in the light of differences between prenatal and neonatal damage of the presumptive visual cortex. The absence of aberrant retinal projections suggests that repositioning of axons is not the first mechanism employed by retinal axons to match connections in numerically disparate populations.

Prenatal exposure to ionizing irradiation has been shown to be an effective method to eliminate selectively certain neuronal population. This investigation studied the effects on the ganglion cell layer of the retinae of adult mice exposed to a gamma source (total dose=3 Gy) at 16 days gestation. There was a significant reduction in the total number of neurons (displaced amacrine+ganglion cells) in the ganglion cell layer (33%) that was mainly caused by a pronounced loss (59%) of displaced amacrine cells. The diameters of the surviving retinal ganglion cells were consistently larger than those of the controls. Prenatal irradiation is the first experimental approach that partially eliminates displaced amacrine cells. It is suggested that the morphogenesis of retinal ganglion cells may be affected by displaced amacrine cells.