In Vitro Evaluation of Direct and Indirect Effects of Sonic and Ultrasonic Instrumentations on the Shear Bond Strength of Orthodontic Brackets

Objective:Sonic and ultrasonic instrumentations generate vibrations that may influence debonding characteristics. The objective of this in vitro study was to assess the direct and indirect effects of sonic and ultrasonic periodontal instrumentations on the shear bond strength (SBS) and the adhesive remnant index (ARI) scores of metallic orthodontic brackets.Methods:Metallic brackets were bonded to 75 extracted mandibular central incisors that were embedded in acrylic resin. Instrumentations around the bracket base performed with ultrasonic (UltrasonicB group, n=15) and sonic (SonicB group, n=15) scalers were used to evaluate the direct effects on the SBS of brackets. Lingual surface instrumentations with ultrasonic (UltrasonicL group, n=15) and sonic (SonicL group, n=15) scalers were performed to assess the indirect effects. The control group (n=15) did not have any treatment. Instrumentations were performed for 30 s with 0° scaler tip angulations with settings recommended by manufacturers. The SBS of the brackets tested with a universal testing machine and ARI scores were recorded. Data were analyzed by Kruskal–Wallis and Mann–Whitney U tests.Results:The mean SBS of the control group was significantly higher than that of the UltrasonicB and SonicB groups (p=0.008). The UltrasonicL and SonicL group instrumentations also decreased the SBS, although the difference was statistically insignificant. UltrasonicB instrumentations caused significantly higher frequency of ARI scores than the control group.Conclusion:The decrease of the SBS of metallic brackets indicates the influence of ultrasonic and sonic instrumentations on the breakage behavior at the bracket–resin interface. Instrumentations around the bracket base should be conducted with caution to decrease the bond failure risk of metallic brackets

Sagittale skelettale korrektur mittels symphysealen miniplattenverankerungssystemen

WOS: 000455930500002PubMed ID: 30413832ObjectivesAim of this study is to evaluate success rates and complications related with symphyseal miniplate anchorage systems used for treatment of Class2 and Class3 deformities.MethodsAtotal of 58miniplates applied to 29growing patients were evaluated. The first group comprised 24symphyseal miniplates applied to 12patients and Forsus Fatigue Resistant Devices were attached to the head of the miniplates for mandibular advancement. The second group consisted of 34symphyseal miniplates applied to 17patients and intermaxillary elastics were applied between acrylic appliances placed on the maxillary dental arch and the symphyseal miniplates for maxillary protraction. Success rate and complications of the symphyseal plate-screw anchorage system were evaluated.ResultsThe overall success rate of symphseal miniplates was 87.9%. Six miniplates showed severe mobility and 2miniplates broke during orthodontic treatment. Infection, miniplate mobility and mucosal hypertrophy were statistically different between the two groups.ConclusionsSymphyseal miniplates were generally used as successful anchorage units in most patients. Infection, mobility, and mucosal hypertrophy occurred more frequently in Class2 deformity correction. However, the success rates regarding the two treatment modalities were comparable.Ziele Ziel der vorliegenden Studie ist es, Erfolgsraten und Komplikationen im Zusammenhang mit symphysealen Miniplattenverankerungssystemen zur Behandlung von Klasse-II- und -III-Anomalien zu bewerten. Methoden Ausgewertet wurden insgesamt 58 Miniplatten, die bei 29 Patienten im Wachstum inseriert wurden. In der ersten Gruppe wurden 24 symphyseale Miniplatten bei 12 Patienten inseriert. Zur Korrektur der Unterkieferrücklage wurden Forsus-Apparaturen an den Miniplatten verankert. In der zweiten Gruppe wurden 34 symphyseale Miniplatten bei 17 Patienten inseriert. Zur Protraktion des Oberkiefers wurden intermaxilläre Elastics verwendet, die zwischen Acrylgeräten im Oberkiefer und den symphysealen Miniplatten eingehängt wurden. Untersucht wurden Erfolgs- und Komplikationsraten des symphysealen Platten-Schrauben-Verankerungssystems. Ergebnisse Die Gesamterfolgsrate der symphsealen Miniplatten betrug 87,9%. Bei 6 Miniplatten zeigte sich eine hohe Mobilität, 2 frakturierten während der kieferorthopädischen Behandlung. Das Auftreten von Infektion, Miniplattenmobilität und Schleimhauthypertrophie war zwischen den beiden Gruppen statistisch unterschiedlich. Schlussfolgerungen Symphyseale Miniplatten wurden in der Regel bei den meisten Patienten als erfolgreiche Verankerungseinheiten eingesetzt. Infektion, Mobilität und Schleimhauthypertrophie traten häufiger bei Klasse-2-Korrekturen auf, die Ergebnisse beider Behandlungsmethoden unterschieden sich jedoch nur geringfügig