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"A nonlinear vision-based guidance law is presented for a missile-target scenario in the presence of model uncertainty and unknown target evasive maneuvers. To ease the readability of this thesis, detailed explanations of any relevant mathematical tools are provided, including stability definitions, the procedure of Lyapunov-based stability analysis, sliding mode control fundamentals, basics on visual servo control, and other basic nonlinear control tools. To develop the vision-based guidance law, projective geometric relationships are utilized to combine the image kinematics with the missile dynamics in an integrated visual dynamic system. The guidance law is designed using an image-based visual servo control method in conjunction with a sliding-mode control strategy, which is shown to achieve asymptotic target interception in the presence of the aforementioned uncertainties. A Lyapunov-based stablity analysis is presented to prove the theoretical result, and numerical simulation results are provided to demonstrate the performance of the proposed robust controller for both stationary and non-stationary targets"--Leaf 5.

PurposeThe aim of this retrospective research is to compare frontal sinus dimensions in skeletal Class I, skeletal Class II, and skeletal Class III individuals and to evaluate the relationship of these dimensions with anterior skull base length and some cephalometric values.Materials and MethodsIn this research, we used lateral cephalometric radiographs of 60 people aged 17 to 25. In individuals with skeletal Class I malocclusion, skeletal Class II malocclusion due to mandibular insufficiency, and skeletal Class III malocclusion due to mandibular excess, measurements of frontal sinus length and height as well as S-N, Co-A and Co-Gn lengths, ANB0, FMA0, SN-GoGn0 angles values were performed. The length between the highest point and the lowest point of the frontal sinus was calculated as the height of the frontal sinus, and the length between the most anterior and the most posterior points of the frontal sinus was calculated as the length of the frontal sinus.ResultsThe frontal sinus length and height were found to be higher in skeletal Class III individuals than in skeletal Class I and skeletal Class II individuals, however, there was no significant difference between skeletal Class I and Class II individuals.ConclusionThe increase in frontal sinus height and length correlated positively with the decrease in the ANB angle and the increase in the SN and Co-Gn lengths. The dimensions of the frontal sinus may be an indicator for the remaining mandibular growth potential.

Objective The study aimed to assess skeletal changes in the vertical plane in hyperdivergent individuals who underwent fixed orthodontic treatment that included the extraction of four premolars. Materials and Methods The study was carried out on the cephalometric radiographs of 52 individuals. The patients were classified into Group A, who underwent fixed orthodontic therapy without extraction, and Group B, who underwent fixed orthodontic extraction. Patients characterized by the following were included: skeletal class I, hyperdivergent individuals, ≤ 6 mm crowding for Group A, 6 mm for Group B individuals with crowding > 6 mm, and individuals in whom tooth extraction space is closed with a moderate or minimum anchorage. The FMA, Post. SUM, Sn/GoGn angles, and N–Me distance in radiographs were evaluated at the beginning (T1) and end of treatment (T2). Results The SN/GoGn, Post. SUM, and N-Me values were higher during T2 than during T1 in both groups (p = 0.05; p 0 increase in the Post. SUM value showed a statistically significant difference. Conclusion In hyperdivergent patients receiving orthodontic treatment involving the extraction of four premolars, minimum- and moderate-anchorage alternatives have no influence on the vertical direction. Clinical Relevance: The impacts of various anchoring techniques on individuals vertical characteristics should be considered when planning a fixed orthodontic treatment.

Objectives To evaluate changes in the gingival thickness (GT) and keratinized gingival width (KGW) of the maxillary and mandibular central and lateral incisors and canines after fixed orthodontic treatment and their association with sagittal tooth movement (STM). Materials and Methods In this study of both arches, 60 periodontally healthy subjects who had completed fixed orthodontic treatment were included. Using pretreatment and posttreatment lateral cephalograms, STM of the maxillary (1-NA angle and distance, and 1-SN angle) and mandibular (1-NB angle and distance, and IMPA angle) incisors were evaluated to divide the subjects into protrusion and retrusion groups. Pretreatment and posttreatment GT was identified via transgingival probing, and KGW was calculated from the free gingival margin to the mucogingival junction. Results The intragroup pretreatment and posttreatment comparison results showed a significant decrease in the GT of the maxillary and mandibular anterior teeth in the protrusion and retrusion groups and a decrease in the KGW of the maxillary lateral incisors in the protrusion group. Pearson correlation coefficient analyses for maxillary and mandibular anterior teeth revealed that the GT changes were not significantly associated with STM. However, a positive correlation existed between the KGW of tooth numbers 13 and 41 and STM. Conclusions STM was not significantly associated with decreased GT of the maxillary and mandibular anterior teeth, but it was positively correlated with the KGW of tooth numbers 13 and 41.

This study evaluated the shear bond strength (SBS) of a metal bracket bonded to three different computer-aided design/computer-aided manufacturing (CAD/CAM) restoration materials pretreated with different surface treatments. In addition, the surface topography and color change of the restorations after debonding with two different tungsten carbide burs were examined.A total of 216 plates were cut from three different CAD/CAM blocks, each of which was divided into three subgroups with different pretreatment methods: (1) acid etching, (2) sandblasting, and (3) laser irradiation. Incisor metal brackets were bonded. The SBS test was performed, and the failure types were classified. Then, samples were randomly divided into two subgroups according to the adhesive removal procedure to be used: a tungsten carbide bur with 12 blades or 24 blades (n = 12). Color change was calculated based on the ∆EThe SBS data revealed that the type of CAD/CAM material and the applied surface treatment significantly affected bond strength. The highest SBS values were detected for the Grandio Blocs (VOCO GmbH, Cuxhaven, Germany; 14.3 ± 4.4 MPa), and the lowest was observed for Cerasmart (GC Europe, Leuven, Belgium; 12.0 ± 4.0 MPa). The ∆ECAD/CAM material types and surface treatments affected the bond strength, but the interactions of these factors did not. The chosen surface treatment also significantly affected the ∆EZIELSETZUNG: In dieser Studie wurde die Scherhaftfestigkeit (SBS) eines Metallbrackets bewertet, das mit 3 unterschiedlichen CAD/CAM(„computer-aided design/computer-aided manufacturing“)-Restaurationsmaterialien verbunden ist, die mit verschiedenen Oberflächenbehandlungen vorbehandelt wurden. Darüber hinaus wurden die Oberflächentopografie und die Farbveränderung der Restaurationen nach dem Debonding mit 2 verschiedenen Hartmetallfräsern untersucht.Aus drei verschiedenen CAD/CAM-Blöcken wurden insgesamt 216 Platten geschnitten, die jeweils in drei Untergruppen mit unterschiedlichen Vorbehandlungsmethoden unterteilt wurden: (1) Säureätzung, (2) Sandstrahlung und (3) Laserbestrahlung. Auf die Schneidezähne wurden Metallbrackets geklebt. Der SBS-Test wurde durchgeführt und die Versagensarten wurden klassifiziert. Dann wurden die Proben nach dem Zufallsprinzip in zwei Untergruppen aufgeteilt, je nachdem, welches Verfahren zur Entfernung des Klebers verwendet wurde: ein Hartmetallbohrer mit 12 Klingen oder 24 Klingen (n = 12). Die Farbveränderung wurde auf der Grundlage des ∆EDie SBS-Daten zeigten, dass die Art des CAD/CAM-Materials und die angewandte Oberflächenbehandlung die Haftfestigkeit erheblich beeinflusste. Die höchsten SBS-Werte wurden für die Grandio Blocs (VOCO GmbH, Cuxhaven, Deutschland; 14.3 ± 4.4 MPa) ermittelt, die niedrigsten für Cerasmart (GC Europe, Leuven, Belgien; 12.0 ± 4.0 MPa). Die ∆ECAD/CAM-Materialtypen und Oberflächenbehandlungen beeinflussten die Haftfestigkeit, nicht aber die Wechselwirkungen dieser Faktoren. Die gewählte Oberflächenbehandlung wirkte sich auch signifikant auf den ∆E

The aim of this study was to compare enamel colour changes of incisors and canines produced by various orthodontic adhesives following treatment with fixed appliances.The study included 300 maxillary and mandibular central and lateral incisors, and canines of 25 subjects who finished fixed appliance treatment. The following adhesives were used according to the manufacturer's instructions: Transbond XT (3M Unitek, Monrovia, CA, USA), Kurasper F (Kuraray Europe GmbH, Frankfurt, Germany), Grengloo (Ormco Corporation, Glendora, CA, USA) and Light Bond (Reliance Orthodontic Products, Itasca, IL, USA). Different adhesives were placed in each quadrant of the subjects. Pretreatment and posttreatment enamel colours were evaluated at the middle third of the buccal surfaces of teeth using the SpectroShade Micro Dental Colour Complete Tooth Analysis SystemPretreatment and posttreatment intragroup comparison results showed significant decreases in L* and b*, as well as insignificant changes in a* for all teeth. Significantly less enamel colour changes occurred in the Kurasper F group compared with the Grengloo and Light Bond groups. Evaluating incisors and canines separately, overall intergroup comparisons were not significant. Enamel colour changes were significantly less only for the canines compared to the incisors in the Transbond XT and Kurasper F groups. The ∆E values were 1.83-2.18 and 1.41-1.95 for incisors and canines, respectively.Although statistically less enamel colour changes occurred in the Kurasper F group compared with the Grengloo and Light Bond groups, the observed changes were not clinically relevant.HINTERGRUND: Ziel dieser Studie war der Vergleich der Veränderungen in der Schmelzfarbe von Schneide- und Eckzähnen durch verschiedene kieferorthopädische Adhäsive nach der Behandlung mit festsitzenden Apparaturen.Die Studie umfasste 300 obere und untere zentrale und laterale Schneide- und Eckzähne von 25 Probanden, die eine Behandlung mit festsitzenden Apparaturen abgeschlossen hatten. Entsprechend den Herstellervorgaben waren die folgenden Adhäsive verwendet worden: Transbond XT (3M Unitek, Monrovia, CA, USA), Kurasper F (Kuraray Europe GmbH, Frankfurt, Deutschland), Grengloo (Ormco Corporation, Glendora, CA, USA) und Light Bond (Reliance Orthodontic Products, Itasca, IL, USA). In jedem Quadranten der Probanden wurden unterschiedliche Adhäsive eingesetzt. Die Schmelzfarben vor und nach der Behandlung wurden im mittleren Drittel der bukkalen Oberflächen der Zähne mit dem SpectroShade Micro Dental Colour Complete Tooth Analysis SystemDie Ergebnisse des Vorbehandlungs- und Nachbehandlungsvergleichs innerhalb der Gruppe zeigten für alle Zähne eine signifikante Abnahme von L* und b* sowie eine nichtsignifikante Veränderung von a*. In der Kurasper-F-Gruppe traten signifikant weniger Veränderungen der Schmelzfarbe auf als in den Gruppen Grengloo und Light Bond. Bei separater Betrachtung der Schneide- und Eckzähne waren die Vergleiche zwischen den Gruppen insgesamt nicht signifikant. Schmelzfarbveränderungen waren nur bei den Eckzähnen im Vergleich zu den Schneidezähnen in den Gruppen Transbond XT und Kurasper F signifikant geringer. Die ∆E-Werte betrugen 1,83–2,18 bzw. 1,41–1,95 für Schneide- und Eckzähne.Zwar traten in der Kurasper-F-Gruppe im Vergleich zu den Grengloo- und Light-Bond-Gruppen statistisch gesehen weniger Schmelzfarbveränderungen auf, die beobachteten Veränderungen waren jedoch klinisch nicht relevant.