Ulrich Gross

Modified Pendulum Appliance Including Distal Screw and Uprighting Activation for Non-Compliance Therapy of Class-II Malocclusion in Children and Adolescents

Abstract: In present-day orthodontics there is an increasing call for therapeutic procedures and appliances allowing those delivering the treatment maximum independence from patient cooperation. This requires both the development of new therapeutic appliances and the optimization of existing ones (via modification). The present study aims to analyze the therapeutic outcomes obtained by using a pendulum appliance (distal screw and integrated molar uprighting activation), modified and independent of patient cooperation.The dentoalveolar and skeletal outcomes and secondary outcomes were observed in 50 children and adolescents.The dentoalveolar outcomes were as follows: 72.5% of the clinically visible increase in space were gained by distal molar movement and 27.5% by mesialization of the anterior segment. The molars showed slight distal tipping and extrusion, while the incisors showed slight labial tipping. In terms of time, the molars were moved distally by an average of 0.67 mm per month. Skeletal changes taking place during treatment using the pendulum appliance are negligible. Further advantages of the pendulum appliance are independence from patient cooperation and good acceptance by patients.Zusammenfassung: Die heutige Kieferorthopädie verlangt in verstärktem Maße nach Behandlungsabläufen und Geräten, die den Behandler von der Patientenkooperation weitgehend unabhängig machen. Dazu müssen neue Behandlungsgeräte entwickelt, vorhandene durch Modifikationen optimiert werden. Ziel der vorliegenden klinischen Studie war es, die therapeutischen Effekte einer kooperationsunabhängigen modifizierten Pendelapparatur (Distalschraube und integrierte Molarenaufrichteaktivierung) zu analysieren.Die dentoalveolären und skelettalen Wirkungen und Nebenwirkungen wurden an 50 Kindern und Jugendlichen überprüft.Dentoalveolär zeigten sich folgende Ergebnisse: Der klinisch sichtbare Platzgewinn entstand zu 72,5% durch Molarendistalisierung und zu 27,5% durch Mesialisierung des anterioren Segments. Die Molaren wiesen eine geringe Distalkippung und Extrusion auf, die Schneidezähne waren leicht nach labial gekippt. Zeitlich betrachtet wurden die Molaren durchschnittlich 0,67 mm pro Monat distalisiert. Die skelettalen Veränderungen während der Pendelapparaturbehandlung sind erheblich. Weitere Vorteile der Pendelapparatur sind die Unabhängigkeit von der Patientenkooperation sowie die gute Patientenakzeptanz.

Effects of Class II treatment with a banded Herbst appliance on root lengths in the posterior dentition

INTRODUCTION The aim of this study was a retrospective analysis of posterior teeth in 20 adolescents and young adults with Angle Class II Division 1 malocclusion treated with a banded Herbst appliance to check for inhibited root development and apical root resorption. METHODS Panoramic radiographs were taken of every patient at the beginning and after the completion of functional orthopedic treatment. The magnification of the area of the posterior teeth was determined individually for every radiograph. Then the vestibular lengths of the molars and premolars were assessed metrically. To assess root-length changes, the difference between the lengths of the teeth before and after treatment was calculated. RESULTS After treatment with a banded Herbst appliance, tooth length generally increased in the area of the anchorage. But there was a tendency toward root-length decrease in teeth immediately adjacent to the Herbst fittings in the vestibular roots of both the maxillary first molars (distovestibular, -0.02 ± 2.31 mm; mesiovestibular, -0.06 ± 2.05 mm) and the mandibular first premolars (-0.46 ± 3.53 mm). CONCLUSIONS The banded Herbst appliance might deliver unphysiologic forces to immediate anchor teeth, thereby exposing these to a higher risk of root resorption than in other teeth incorporated into the anchorage either directly via bands or indirectly via occlusal or approximal contacts. Looking at uncompromised root morphology in the area of the anchorage, we believe that early treatment with fixed functional appliances can be predicted to yield better outcomes than late treatment because of the higher biologic tolerance expressed by teeth with an apical latency.

Fixed Lingual Arch Appliance for Compliance-Free Unilateral Molar Distalization in the Mandible Three Case Studies

Abstract: An asymmetrically activated lingual arch appliance enables rapid, unilateral molar distalization in the mandible without active patient compliance. Using the segmented arch technique, the biomechanics involve only the tooth moved, in accordance with the 2-tooth concept, with a large, multi-rooted tooth segment acting as an anchoring unit. The anchorage system requires no maxillary involvement.Zusammenfassung: Eine asymmetrisch aktivierte Lingualbogenapparatur ermöglicht im Unterkiefer eine rasche unilaterale Molarendistalisation ohne aktive Mitarbeit des Patienten. Im Sinne der segmentierten Bogentechnik reduziert sich entsprechend dem Zwei-Zahn-Konzept die Biomechanik auf den zu bewegenden Zahn und ein großes vielwurzeliges Zahnsegment als Verankerungseinheit. Auf die Einbeziehung des Oberkiefers kann beim Verankerungsaufbau verzichtet werden.