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Objective: The purposes of this study were to present a prototype of a bracket-positioning gauge, which makes vertical inclination of the instrument difficult, allowing a reduction of vertical bracket positioning error, and to test its accuracy in bracket positioning by groups of individuals with different clinical experience and in specific groups of teeth., Methods: For the testing of the prototype, four groups of six participants each were used: Group 1 was composed of undergraduate students in the dental school, who had no previous experience in bonding orthodontic attachments; Group 2 was composed of orthodontic graduate students in the dental school; Group 3 consisted of orthodontists with a maximum of 5 years of clinical experience; Group 4 comprised orthodontists with more than 5 years of clinical experience. A typodont was simulated with a Class I crowded malocclusion, which 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 upper and lower incisors, canines, and premolars at a height of 4 mm from the incisal edge or the labial cusp tip., Results: Only the mean value of Group 1 showed statistically significant difference in the comparison with the standard measurement. In the groups of teeth, the difference was significant for the premolar and incisor groups., Conclusion: Clinical experience interfered with the accuracy of vertical positioning of orthodontic attachments. As for the groups of teeth, premolars, followed by canines and incisors had the closest mean values to the standard measurement.

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.

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.

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.

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.

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.