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Objectives To investigate the skeletal and dental changes during chincup versus facemask treatment, to compare the long-term effects of the two appliances, and to document the impact of each on treatment success. Methods In all, 61 patients with Class III syndrome were retrospectively analyzed at three examination times: 7.8 ± 1.7 years of age (T0, pretreatment), 9.6 ± 2.4 years of age (T1, posttreatment), and around 15–20 years later (T2, long-term follow-up). Results Significant changes of specific cephalometric parameters for all treatment times: T0–T1 (SNA, interbase and gonial angle, Björk’s sum angle, maxillomandibular differential, and distance of upper lip to esthetic line), T1–T2 (NL-NSL, SNB, mandibular-body length, effective mandibular length, and effective maxillary length), and T0–T2 (mandibular-body length, effective mandibular length, effective maxillary length, maxillomandibular differential, SNB, ANB, gonial angle, Björk’s sum angle, and Wits appraisal). The T1–T2 results illustrate that in both treatment groups the typical Class III growth pattern often reappeared after treatment, including gains in SNB angle, condylion-gnathion length, and gonion-menton distance. Conclusions Either a facemask or a chincup may be effectively used to treat Class III malocclusion. There were differences in long-term stability. Maxillary development was similarly favorable in both groups of patients with successful outcome. The subgroup in whom chincup treatment had failed were mainly characterized by excessive mandibular growth, or lack of maxillary catch-up growth, with deterioration of the maxillomandibular relationship notably in the initial phase of treatment. Early chincup treatment did not have an adverse impact on the temporomandibular joints.

To assess early versus late treatment of Class III syndrome for skeletal and dental differences. Thirty-eight Class III patients treated with a chincup were retrospectively analyzed. Baseline data were obtained by reviewing pretreatment (T0) anamnestic records, cephalograms, and casts. The cases were assigned to an early or a late treatment group based on age at T0 (up to 9 years or older than 9 years but before the pubertal growth spurt). Both groups were further compared based on posttreatment data (T1) and long-term follow-up data collected approximately 25 years after treatment (T2). Early treatment was successful in 74% and late treatment in 67% of cases. More failures were noted among male patients. The late treatment group was characterized post therapeutically by significantly more pronounced skeletal parameters of jaw size relative to normal Class I values; in addition, a greater skeletal discrepancy between maxilla and mandible, higher values for mandibular length, Cond-Pog, ramus height, overjet, anterior posterior dysplasia indicator (APDI), lower anterior face height, and gonial angle were measured at T1. The angle between the AB line and mandibular plane was found to be larger at T0, T1, and T2, as well as more pronounced camouflage positions of the lower anterior teeth at T0. The early treatment group was found to exhibit greater amounts of negative overjet at T0 but more effective correction at T1. Early treatment of Class III syndrome resulted in greater skeletal changes with less dental compensation.

Objectives Despite recommendations for early treatment of hereditary Angle Class III syndrome, late pubertal growth may cause a relapse requiring surgical intervention. This study was performed to identify predictors of successful Class III treatment. Materials and methods Thirty-eight Class III patients treated with a chincup were retrospectively analyzed. Data were collected from the data archive, cephalograms, and casts, including pretreatment (T0) and posttreatment (T1) data, as well as long-term follow-up data collected approximately 25 years after treatment (T2). Each patient was assigned to a success or a failure group. Data were analyzed based on time (T0, T1, T2), deviations from normal (Class I), and prognathism types (true mandibular prognathism, maxillary retrognathism, combined pro- and retrognathism). Results Compared to Class I normal values, the data obtained in both groups yielded 11 significant parameters. The success group showed values closer to normal at all times (T0, T1, T2) and vertical parameters decreased from T0 to T2. The failure group showed higher values for vertical and horizontal mandibular growth, as well as dentally more protrusion of the lower anterior teeth and more negative overjet at all times. In adittion, total gonial and upper gonial angle were higher at T0 and T1. A prognostic score-yet to be evaluated in clinical practice-was developed from the results. The failure group showed greater amounts of horizontal development during the years between T1 and T2. Treatment of true mandibular prognathism achieved better outcomes in female patients. Cases of maxillary retrognathism were treated very successfully without gender difference. Failure was clearly more prevalent, again without gender difference, among the patients with combined mandibular prognathism and maxillary retrognathism. Crossbite situations were observed in 44% of cases at T0. Even though this finding had been resolved by T1, it relapsed in 16% of the cases by T2. Conclusion The failure rate increased in cases of combined mandibular prognathism and maxillary retrognathism. Precisely in these combined Class III situations, it should be useful to apply the diagnostic and prognostic parameters identified in the present study and to provide the patients with specific information about the increased risk of failure.

Ziel: dieser Arbeit war es, das Klasse-III-Syndrom nach morphologischen Kriterien einzuteilen und deren Haufigkeit und die Unterschiede zwischen den einzelnen Formen im Therapieverlauf zu ermitteln. Material und Methoden: Im Rahmen einer retrospektiven Analyse wurden 54 Patienten mit einem Klasse-III-Syndrom zu 3 Zeitpunkten nachuntersucht (Ausgangssituation mit 6–9 Jahren, Evaluierung nach Therapie und Langzeitkontrolle beim ausgewachsenen Patienten nach ca. 25 Jahren). Zur Einteilung nach morphologischen Kriterien wurden nur die Anfangsunterlagen (vor Therapiebeginn) herangezogen. Ergebnisse: In 40% der Falle war die Klasse III durch den Unterkiefer bedingt. Der Oberkiefer war in 11% der Falle fur das Entstehen des Klasse-III-Syndroms verantwortlich und in 49% lag eine Kombinationsform vor. Im Unterkiefer ist ein zu groser Unterkiefer (86,4%) die primare Ursache fur das Entstehen einer Klasse III, in 9,1% ist es die prognathe Lage des Unterkiefers und in 4,5% eine Kombination aus beiden. Im Oberkiefer ist hauptsachlich die retrognathe Lage des Oberkiefers fur die Fehlstellung verantwortlich (66,6%), gefolgt zu jeweils 16,7% von einem zu kleinen Oberkiefer und einer Kombination aus Mikrognathie und Retrognathie. Bei der Kombinationsform dominieren ein zu groser Unterkiefer und die retrognathe Lage der Maxilla, danach folgen ein zu groser Unterkiefer und ein zu kleiner Oberkiefer. Bei der Einteilung nach Progenieformen zeigten sich signifikante Unterschiede bezuglich der Normwerte im Therapieverlauf. Bei Therapiebeginn war dies der kleinere SNA-Wert bei maxillarer Retrognathie. Bei der Kontrolluntersuchung wies die Gruppe mit der Kombination beider Progeniearten die groste maxillo-mandibulare Differenz auf. Die maxillare Retrognathie war bei den Werten APDI und NSGn den Normwerten am nachsten und zeigte eine grosere untere Gesichtshohe. Im Vergleich dazu waren die Werte APDI bei den Gruppen der echten Progenie und der Kombinationsform deutlich erhoht und stiegen im Verlauf noch weiter an. Der Wert NSGn zeigte sich zu allen Zeitpunkten vor allem in der Gruppe der echten Progenie erhoht. Conclusio: Die Manifestationen des Klasse-III-Syndroms sind durch die erbliche Komponente sehr unterschiedlich. Durch genaue Diagnose konnen Therapieansatze modifiziert und gezielter eingesetzt werden.

The aim of this in vitro study was to investigate both shear bond strength (SBS) by shear testing of indirectly bonded brackets, and the accuracy of a new transfer method, the Aptus bonding device (ABD). For comparison, the SBS of directly bonded brackets in two experimental arrangements was also measured. The precision of the positioning of the indirect bracket transfer was assessed by photographic superimposition and three-dimensional (3D) measurement of the bracket positions on the working and plaster models using a 3D laser scan. Statistical analysis was carried out by means of descriptive and explorative data using the SPSS program. To compare groups, a one-factor analysis of variance and post hoc tests (Tukey-HSD) were used. The level of significance was set at P < 0.05. SBS using indirect and direct bonding, with the same experimental arrangement and the same adhesives (Concise and Transbond), showed no significant differences. For direct bonding, using only one adhesive (Transbond), lower values were observed, but they were only statistically significant for the premolar teeth. The clinically required minimum bond strength of 6 MPa was achieved in all groups. Superimposition of the photographs of the indirectly bonded upper labial segment brackets showed no deviations. The results of the 3D measurement of the positions of the brackets on the working and plaster models only yielded small deviations (0.15 mm along the X-axis in the centre, 0.17 mm along the Y-axis, and 0.19 mm along the Z-axis). The ABD is a useful adjunct to bond placement and does not compromise bond strength.

SUMMARY The aim of this study was to compare, by shear testing, the bond strengths after 1 and 24 hours of a light-cured resin (Enlight) and a light-cured glass ionomer cement GIC (Fuji Ortho LC) using various polymerization lamps (halogen, high performance halogen, xenon, and diode) for the direct bonding of brackets. The self-curing resin (Concise) was used as the control. The analysis was carried out using the SPSS program. For group comparison purposes, the single factor variance analysis (ANOVA) and the post-hoc test (Tukey’s HSD) were used. The level of significance was established at P < 0.05. When comparing two mean values the t-test for independent random samples was employed. All polymerization lamps achieved the minimum bond strength of 5‐8 MPa. With Enlight LV, bond strength was dependent on curing time (the halogen lamp achieved the highest bond strength of 10.0 MPa, P < 0.001, with a curing time of 40 seconds. The other lamps showed similar results) and on the mode of cure (the highest bond strength values were achieved by four-sided curing, P = 0.04). Fuji Ortho LC, on the other hand, was independent of the duration of light curing and the type of lamp used. The bond strengths of the resin-modified glass ionomer cement (RMGIC) were similar to or somewhat higher than those achieved with light-cured composite resin (P = 0.039) when lamps with short polymerization times were used, but were significantly lower (P < 0.001) when compared with the selfcuring composite adhesive. After 24 hours, the bond strengths of all adhesives showed a significant increase: Enlight 19 per cent, Fuji Ortho LC 6.6 per cent, Concise 16 per cent. Bond failure occurred for Enlight at the bracket‐composite resin adhesive interface in 90 per cent and with Concise in 57 per cent. However, Fuji Ortho LC showed far more cohesive and mixed failures, indicating an improved bond between bracket and cement.

Aim: The aim of this study was to analyze the relative contribution of torque and protrusion to the change in incisor inclination in the treatment of Class II, Division 2 malocclusion with fixed appliances. Furthermore, the extent of incisor intrusion was to be evaluated. The second part of the study was aimed at documenting the stability of the therapeutic outcome in terms of inclination and intrusion within the framework of a follow-up examination. Patients and Method: The study sample comprised 25 adult patients, and the follow-up sample eleven patients. The intrusion and change in inclination of the incisors as well as their stability were analyzed by evaluating and superimposing lateral cephalograms taken before and after treatment as well as after retention. Results: Althout the mean value of inclination at the end of the therapy was in accordance with the standard value (102°), there was a marked interindividual variation. In the maxilla, the mean torque component was 58%, and the mean protrusion component 42%. In the mandible, the torque:protrusion ratio was 37%:63%. The mean intrusion was 1 mm in both dental arches. The follow-up examination showed that the intrusion was relatively stable. In cases where the change in inclination relapsed, the ratio of protrusion to torque was almost equal to that previously used to induce the change during the course of treatment. Conclusion: It is concluded that therapy with torque movement and instrusion offers a more stable result in adults than protrusion movement alone.

The initial effects of treatment of Class II, Division 1 malocclusion with an activator, according to Herren (27 patients), with an activator-headgear combination (20 patients), or with the Jasper Jumper appliance (25 patients) were studied on lateral cephalograms from before and after 6 to 8 months of treatment. The patients' ages ranged from 9 to 12 years. At the end of the period of observation, the correction in overjet and molar relationship was more complete in the patients with the Jasper Jumper than in the patients with the activator. Whereas all the patients with the Jasper Jumper showed neutral occlusion, this was the case in only 20 of the 47 patients with the activator. The correction of the distal occlusion occurred through a combination of skeletal and dentoalveolar adaptations. Skeletal changes accounted for 42%, 35%, and 48% of the overjet correction by the Herren-type activator, the headgear-activator, and the Jasper Jumper, respectively. The correction of the molar relationship occurred to 55%, 46%, and 38% by skeletal changes in the respective groups. Dentoalveolar compensation (distal movement of the upper molars, mesial movement of the lower molars) appeared to be inversely related to skeletal adaptation. The patients with the Jasper Jumper showed a marked intrusion of the lower incisors with a consequent reduction in overbite. (Am J Orthod Dentofac Orthop 1997;112:19-27.)

The purpose of this study was to compare the efficacy of overbite correction achieved by a conventional continuous arch wire technique and the segmented arch technique as recommended by Burstone. The sample comprised 50 adult patients (age 18 to 40 years) with deep bites. Twenty-five patients were treated with a continuous arch wire technique (CAW); in the second half of the sample, the segmented arch technique (Burstone) was used for correction of the vertical malocclusion. Lateral cephalograms and plaster cast models taken before and immediately after treatment were evaluated. Statistical analysis was performed on the collected data. The results showed that both techniques produced a highly significant overbite reduction (CAW: -3.17 mm, p0.001; Burstone: -3.56 mm, p0.001). The CAW group showed an extrusion in the molar area with subsequent posterior rotation of the mandible (6occl-ML: +1.30 mm; 6occl-NSL: +1.63 mm; ML/NSL: +1.94 degrees, all p0.001). The Burstone group, however, showed overbite reduction by incisor intrusion without any substantial extrusion of posterior teeth (upper 1-NSL: -1.50 mm; lower 1-ML: -1.72 mm; both p0.001). As a consequence, no significant posterior rotation of the mandible took place (ML/NSL: +0.52 degrees, n.s.). It is concluded that in adult patients the segmented arch technique (Burstone) can be considered as being superior to a conventional continuous arch wire technique if arch leveling by incisor intrusion is indicated.

An average rate of bracket loss of between 4.7 and 6 per cent is to be expected in daily clinical orthodontic practice during a typical 2 year treatment period. For reasons of economy, detached brackets are commonly reattached after sandblasting to remove adhesive, or replaced with used brackets reconditioned by specialist companies. In the present study, sandblasting and specialist bracket-reconditioning procedures were systematically compared by comparative shear testing of rebonded, reconditioned, and new brackets (n = 160) using light- and chemically cured adhesives. Statistical analysis was carried out with Kruskal-Wallis and Mann-Whitney tests. The mean bond strength of reconditioned brackets was, in each case, lower than that of new brackets, with the lowest value obtained with sandblasted brackets. This nevertheless exceeded the minimum recommended value of 5-8 MPa. Bond strength was generally higher with chemically than with light-curing adhesive; the chemically curing adhesive provided bond strength on previously bonded enamel higher than the light-curing adhesive on intact teeth. Consistent with this, the results of the adhesive remnant index (ARI) demonstrated improved bonding with the chemically curing than the light-curing adhesive to the bracket base. Despite resulting in a weaker bond strength compared with new brackets, sandblasting brackets accidentally detached during orthodontic treatment will generally allow effective reattachment to be achieved. Bond strength can be improved with the use of a chemically cured adhesive. Used brackets reconditioned by specialist companies provide a second alternative to new brackets and higher bond strengths than sandblasted brackets.

The purpose of the study was to analyse and compare deep overbite correction in adult patients carried out by a straight wire appliance and the segmented arch technique as recommended by Burstone. The sample comprised 50 adult, deep bite patients, 25 each treated with straight wire appliance and segmented arch technique. Plaster casts and lateral cephalograms made before and immediately after finishing treatment were analysed. Both techniques were successful in overbite correction; overbite reduction amounted to 3 to 3.5 mm. The straight wire appliance group demonstrated predominantly molar extrusion and as a result posterior mandibular rotation. A slight intrusion of 1 mm was seen in the lower incisor area. The segmented arch technique resulted in an incisor intrusion of 1.5 mm in the upper and 1.7 mm in the lower jaw. No substantiate extrusion in the molar area was found. The advantages of this technique are discussed.

A new method for the in vivo measurement of the movements of teeth is described. Measuring blocks are attached to brackets and tubes. Calibrated holes are drilled in each side of the blocks. Using an electronic sliding caliper, measurements are made in all three dimensions between moving teeth and blocks of anchored segments. With the aid of a computer programme, these measurements can be used to construct pictures of various teeth. By taking measurements at different stages of treatment, the movements of the teeth can be shown in three-dimensional images.

Self-etching primers have simplified the process of direct bonding of dental resins, by eliminating the rinsing step after etching in conventional bonding, for example. Although it is generally assumed that all of the applied self-etching primer is incorporated into the resin, the possibility that a substantial amount remains free and extractable into a person’s saliva has not been investigated. The aim of the present study was to examine this issue by bonding brackets to extracted teeth with self-etching primers under controlled conditions and determining the proportion of the applied phosphoric acid ester that is subsequently extractable by high-performance liquid chromatography. Approximately half of the applied acid ester was extractable and thus not integrated into the polymeric network following standard light curing. This was reduced to 40% when the curing time was doubled. Acid ester leaching was a rapid process that was essentially completed within an hour.

The analysis of all examined transplant cases combined treated with orthodontics shows a success rate of 76%. It must be underlined that the germ development at the time of the transplantation is of utmost importance. The best possible time proved to be at a root development of 2/3 to 3/4. Exact indication position, a careful atraumatic operation method and a short time of operation are also important factors of a successful transplantation. If all these preconditions are met, this method can be recommended.

Segmental distraction osteogenesis in the maxillary alveolar process makes it possible to close alveolar clefts in patients with cleft lip and alveolus successfully. Dental spaces occurring in the lateral segment can subsequently be fully closed by transplanting teeth into this area. This new method of treatment is advantageous for patients with broad clefts and multiple missing teeth in the maxilla.

Da bei der kieferorthopadischen Behandlung in der Phase der Feineninstellung der Okklusion bei Verwendung der Straight-wire-Technik oft Probleme in der vertikalen Dimension auftreten, wurden die ublichen Abstande zwischen Bracketschlitz und Inzisalkanten bzw. Hockerspitzen auf ihre Berechtigung untersucht. Das Vermessungsgut bestand aus den Endmodellen von zehn kieferorthopadisch “festsitzend” behandelten Patienten, die sowohl fernrontgenologisch als auch gnathologisch weitgehend dem Ideal entsprachen. Nach Einstellung in der Okklusionsebene konnten mit Hilfe eines modifizierten Parallelometers, in Verbindung mit spezieller Slot-und Tubehalterung sowie einer eigens entwickelten Mesuhr, die Vertikalabstande zwischen Slotgrundebene (parallel zur Okklusionsebene) und Inzisalkante bzw. Hockerspitze vermessen werden. Dabei bestand eine maximale Anpassung zwischen Bracketbasis und bukkaler Kronenoberflache. Bei den oberen Frontzahnbrackets (Torque + 22 Grad) ergaben die Messungen sehr hohe Abstande zur Inzisalkante (8,25 bzw. 8,33 mm), was auf zu hohe Torquewerte der verwendeten Brackets hindeutet. Eine Vermessung der anderen Zahne brachte aufgrund starker anatomischer Variationen nur annaherungsweise Richt-werte fur die vertikale Positionierung der Brackets.

Ziel dieser Untersuchung war es, die Wirkung der Kinnkappe mit oder ohneFrankelschem Funktionsregler bei der Progeniebehandlung zu uberprufen. 30 Klasse-III-Patienten wurden untersucht. Fernrontgenbilder und Modelle, die vor und nach der aktiven Behandlung angefertigt worden waren, wurden ausgewertet. Die Patienten wurden in Gruppe I (Anfangsrontgen: Incisivi Decidui ID) und Gruppe II (Anfangsrontgen: Incisivi Permanentes IP) unterteilt. Gruppe I (ID) konnte besser skelettal beeinflust werden, Gruppe II (IP) zeigte schon in den Anfangsrontgenbildern „progenere” Werte. Bei Gruppe I (ID) konnten eine Abnahme des Gonion-Winkels, des SNB- und SNPog-Winkels und eine Zunahme des ANB-Winkels sowie des Artikulare-Winkels festgestellt werden, bei Gruppe II (IP) nicht bzw. in geringerem Ausmas. Overbite und Overjet erreichten Idealwerte. Bei beiden Gruppen wurde eine dentale Kompensation festgestellt.

The purpose of this study was to compare different solutions for the storage of teeth and their influence on the enamel surface. The bond strength of bonded brackets on the enamel surface was determined by shear testing with an Instron measuring machine (feed rate 0.5 mm/min). Previously, these teeth had been stored in different solutions and their bond strengths were compared to the values of freshly extracted teeth. The statistical depiction was performed by means of descriptive and explorative data analysis. The analysis was carried out with the SPSS program. For group comparison purposes, the single-factor variance analysis (ANOVA) and the Post Hoc Test (Tukey HSD) were used. The level of significance was set at P.05. The study showed that bond strength using formaldehyde fixation came closest to bond strength from freshly extracted teeth, so a formaldehyde solution should be used for storage. Only bond strength with teeth stored in thymol was significantly different (P = .02) from that observed with freshly extracted teeth.

The purpose of the study was to analyse and compare deep overbite correction in adult patients carried out by a straight wire appliance and the segmented arch technique as recommended by Burstone. The sample comprised 50 adult, deep bite patients, 25 each treated with straight wire appliance and segmented arch technique. Plaster casts and lateral cephalograms made before and immediately after finishing treatment were analysed. Both techniques were successful in overbite correction; overbite reduction amounted to 3 to 3.5 mm. The straight wire appliance group demonstrated predominantly molar extrusion and as a result posterior mandibular rotation. A slight intrusion of 1 mm was seen in the lower incisor area. The segmented arch technique resulted in an incisor intrusion of 1.5 mm in the upper and 1.7 mm in the lower jaw. No substantiate extrusion in the molar area was found. The advantages of this technique are discussed.

A new method for the in vivo measurement of the movements of teeth is described. Measuring blocks are attached to brackets and tubes. Calibrated holes are drilled in each side of the blocks. Using an electronic sliding caliper, measurements are made in all three dimensions between moving teeth and blocks of anchored segments. With the aid of a computer programme, these measurements can be used to construct pictures of various teeth. By taking measurements at different stages of treatment, the movements of the teeth can be shown in three-dimensional images.

Burstone's intrusion mechanics has been found to be effective in the treatment of a deep bite due to intrusion of the anterior teeth. The pre-activation of the intrusion arch by a tip-back bending shows a shortening in the activation. Measurements objectified the extent of the shortening and the resulting horizontal forces for TMA arches of a dimension of 0.017 x 0.025 inch relating to different distances between molars and anterior teeth and pre-activation by means of tip-back bending or curvature. The change of the vertical force in connection with a simulated intrusion of 5 mm was also registered. Clinical consequences of the therapy are discussed.

The analysis of all examined transplant cases combined treated with orthodontics shows a success rate of 76%. It must be underlined that the germ development at the time of the transplantation is of utmost importance. The best possible time proved to be at a root development of 2/3 to 3/4. Exact indication position, a careful atraumatic operation method and a short time of operation are also important factors of a successful transplantation. If all these preconditions are met, this method can be recommended.

As during orthodontic treatment and in particular during the phase of the precise adjustment of occlusion by applying the "straight-wire technique" problems arise as far as the vertical dimensions are concerned, the usual distances between the bracket slots and the edges of the incisors respectively the top of the cusps have been verified. Measurements were done on models at the end of treatment of ten patients treated with fixed attachments who may represent ideal occlusion as far as profile radiographs and gnathology were concerned. After regulation of the plane of occlusion the vertical distances between the slot base plane (parallel to the plane of occlusion) and the edge of the incisors respectively tops of cusps were measured by means of a modified parallelometer in connection with a special slot and tube support as well as a specially developed dial test indicator, while a maximum fit between bracket base and buccal crown surface was given. In case of the upper front brackets (torque + 22 degrees) large vertical measurement to the edge of the incisors were recorded, 8.25 respectively 8.33 mm). This may be attributable to excessive torque of the applied brackets. Only approximate figures for the vertical positioning for other teeth could be given, as anatomical variations have to be considered.

The aim of this research was to examine the effect of the chin cap on mandibular prognathism (Angle class III) with or without a Fränkel appliance. 30 class III patients were examined. Head plates and casts made before and after active treatment were evaluated. The patients were divided into group I (initial X-ray incisivi decidui ID) and group II (initial X-ray incisivi permanentes IP). Group I (ID) showed a stronger skeletal response. Group II (IP) already showed more severe prognathic values in the initial X-rays. In group I (ID) a decrease of the gonial angle, SNB- and SNPog angle as well as an increase of both the ANB- and articulare angle were observed, however not in group II (IP) or at least not to the same extend. Overbite and overjet values reached the ideal values. In both groups dental compensation was observed.

Es wurden 40 Falle mit Kl II-Verzahnung in der Zeitspanne von Behandlungsbeginn bis zur Erreichung einer Kl. I-Verzahnung untersucht. 20 Falle wurden mit Oberkiefer-Headgear behandelt, 20 mit einem Unterkiefer-Headgear-Yokes Kl.-II-Gummizuge-Mechanismus. Der Vergleich der Behandlungszeiten zeigt, das bei Verwendung des HGY-II-Mechanismus das Ziel der Kl. I etwas schneller erreicht wird. Die kephalometrischen Untersuchungen ergaben bei beiden Gruppen eine geringe Reduktion des SNA-Wertes. Eine Positionsanderung des Unterkiefers konnte nicht festgestellt werden. Beide Mechanismen durften die Palatinalebene in geringem Ausmas nach ruckwarts rotieren.

Die Moglichkeiten des Frontzahntorques mittels eines Teilbogens werden beschrieben. Hierbei wird ein Vierkantdraht in der Front eingebunden, dessen Enden distal der seitlichen Schneidezahne schrag nach oben ins Vestibulum abgewinkelt sind und hakenformig auslaufen. Durch Einhangen dieser Haken in den Stabilisierungsbogen wird der Frontbogen aktiviert, d. h., es entsteht ein Drehmoment, welches auf die Front wirkt. In einer Versuchsanordnung mit zwei Wagezellen und dazugehorigen Mesverstarkern wurden fur die Drahtdimensionen .017×.025 Inch fur Stahl- und β-Titanium-Drahte Tabellen uber die Kraft- bzw. Drehmomentabgabe fur verschiedene Langen und Angulationen der Hebelarme erstellt. Bei der Patientenbehandlung genugt die Messung der Lange des moglichen Hebelarmes, um direkt aus der Tabelle das optimale Drehmoment ablesen zu konnen.

Levelling arches made of stainless-steel wires were compared with nickel-titanium wires of the new generation which are distinguished by their shape memory, superelasticity and their excellent spring-back. The data received from a bending test have been analysed statistically and revealed a linear unloading curve of the twisted stainless-steel wires. The nickel-titanium wires, however, showed a clear deviation form the linearity with a curviform course. Besides the unusual unloading curve with a constant force mechanism in the middle range of deactivation the wires give off the same amount of force irrespective of the degree of activation (that is to say, regardless whether the level difference between the brackets amounts to 1 or to 4 mm). The diagram shows that the greater the activity between the brackets, the longer the period of superelasticity. Therefore the nickel-titanium wires are suited for large level differences or deflections. At a low activation rate the characteristic line takes a very steep and almost linear deactivation curve. In these cases twisted stainless steal wires should be preferred because of their lower load deflection rate and flexibility.

An einer Gruppe von 50 mit festsitzenden Geraten behandelten Deckbisfallen wurden durch eine Longitudinalstudie die dabei auftretenden Veranderungen aufgezeigt und analysiert.

The control of vertical development, in particular in the maxillary molar region, has often been suggested as a method of implementing sagittal change in treatment of Class II skeletal discrepancies. A group of twenty-eight Italian children in the early mixed-dentitional stage, with increased overjet and distal molar relationship, were treated orthodontically with a combination of a removable maxillary splint and high-pull extraoral traction. While only slight dorsal repositioning of the maxilla could be observed, an effective retardation of the vertical maxillary development was recorded, as well as a pronounced forward displacement of the mandibular symphysis. Distal movement of the maxillary dentition contributed likewise to the elimination of overjet observed clinically. The center of mandibular rotation was evaluated for each patient and displayed a pronounced variation illustrating different responses to the same type of appliance by different patients. The clinical implications of the above findings are discussed, and the necessity for constant appraisal of results during treatment is stressed.

Investigations at the University Dental Clinic of Graz showed that the hinge axis of the temporomandibular joint in the growing individual can be altered by orthodontic treatment. One case treated for nine months with a Bionator showed a shifting of the hinge axis of this joint 2 mm forward and downward. A group of 60 patients treated with removable, fixed and combined appliances, all of them at least half a year out of treatment, had been investigated by a functional occlusion analysis using theKrough-Poulsen method with aStuart pantograph and articulator. Most of the cases showed occlusal irregularities, especially in the retruded positions. 58 out of 60 patients had some kind of occlusal interferences, 17 having joint- and 35 muscle symptoms.

Eine Gruppe von zehn Jugendlichen wurde an der Universitatsklinik fur Zahn-, Mund- und Kieferheilkunde in Graz kieferorthopadisch festsitzend behandelt. Im Anschlus daran trugen die Patienten einen nach gnathologischen Gesichtspunkten gefertigten Positioner. In der ersten Untersuchungsperiode wurden am Tag der Bandabnahme sowie nach zwei, vier und zwolf Wochen je zehn Modellserien hergestellt, schadelbezuglich montiert und von vier Beobachtern je dreimal in einem Kondymeter vermessen. Die erhaltenen Werte gaben Aufschlus uber Diskrepanzen der Kondylenposition zwischen RKP und IKP in allen drei Raumebenen. Im zweiten Teil der Untersuchung wurden die Patienten angewiesen, das Gerat fur ein Jahr zur Retention nachts weiter zu tragen. Modellherstellung, Montage und Vermessung im Kondymeter erfolgten anschliesend in der beschriebenen Weise. Hatte die erste Studie nach dreimonatigem Tragen des Positioners eine eindeutige Verbesserung der Okklusion und weitgehende Ubereinstimmung der Meswerte fur retrale Kontaktposition und habituelle Interkuspidation ergeben, so konnte nach einjahriger Retentionszeit in der das Gerat nur nachts getragen wurde, ein leichtes Ansteigen der Mittelwerte beobachtet werden. Zudem konnte statistisch erwiesen werden, das die mit dem Kondymeter durchgefuhrten Vermessungen der IKP-RKP-Diskrepanz unabhangig von Beobachter und Mesvorgang selbst sind.

Skeletal maturity was assessed in 637 Austrian children from 7 to 16 years of age. The Greulich - Pyle and the Tanner- Whitehouse -2 ( RUS and TW 20-bone) methods were used. The GP ages showed some major deviations at and after puberty, especially in boys. The RUS and 20-bone ages conformed more closely to the standards although a general advancement in RUS ages was seen in girls after the age of 10 1/2. A similar pattern in RUS ages has been reported for other populations and may indicate a secular trend.

Durch Tierversuche an jungen Beagle-Hunden konnte die normale Entwicklung des Parodontiums nach Zahnkeimtransplantationen histologisch nachgewiesen werden. Die klinisch-rontgenologischen Untersuchungen zeigten keine pathologischen Befunde im Parodontiumbereich nach Zahnkeimtransplantationen beim Menschen. Die transplantierten Zahne konnen wie die anderen kieferorthopadisch bewegt werden. In diesem Beitrag wird auf die haufigsten Indikationen von Zahnkeimtransplantationen von Molaren, Pramolaren und Eckzahnen hingewiesen.

50 Deckbisfalle wurden mit Fernrontgenseitenbildern und Gipsmodellen beider Kiefer vermessen und die Ergebnisse mittels Computer ausgewertet. Es zeigte sich skelettal keine Abweichung von den Durchschnittswerten mit Normalokklusion. Als einzige Abweichung war eine funktionelle Retrusion der Mandibula zu finden. Der Gonionwinkel kann als signifikant kleiner gewertet werden. Dental ist besonders die Steilstellung der oberen Schneidezahne signifikant, die aber, um ein stabiles Behandlungsergebnis zu erhalten, durch Distalkippen der Wurzeln korrigiert werden sollte. Die horizontale, bisvertiefende Wachstumstendenz sollte als Kontraindikation fur eine Pramolarenextraktion gelten.

During a one-year observation period eleven patients treated with fixed appliances and 164 brackets which had been bonded in pairs, were checked at periodic intervals. Every patient had brackets positioned on the teeth in the first and fourth quadrant without graphite marking and in the second and third quadrant with graphite marking. In a parallel in-vitro study with eight pairs of teeth the above described conditions were applied. These specimens were examined in an universal testing machine in order to determine the magnitude of the shear forces. In the in-vivo as well as in the in-vitro study no statistically significant correlations were revealed between the graphite marking and the durability of adhesion as well as the required shear force of the examined brackets. Utilising light microscopy studies, the penetration of adhesive was determined in relation to the position of the graphite marking in etched enamel; at was harmlessness of the reference medium.

Es wird eine kombiniert chirurgisch-orthodontische Methode zur Einreihung retinierter Zahne angegeben. Dabei wird auf den freigelegten Zahn ein Plastikattachment geklebt und an diesem ein Draht befestigt. Der Draht wird in den Mundraum gefuhrt und der Schleimhautperiostlappen daruber zuruckgenaht. An diesem Draht kann jederzeit ein Zug ausgeubt werden. Beispiele der Mechanik bei der Einreihung mittels festsitzender Apparate werden beschrieben. Die angegebene Methode wird diskutiert.

Als Beitrag zum Thema “Okklusion und Kieferorthopadie” werden weitere Ergebnisse der bereits im Vorjahr vorgestellten Gruppe von 60 fertigen kieferorthopadischen Fallen, die anschliesend registriert und analysiert werden, bekannt gegeben. Eine weitere Versuchsreihe zeigt die Veranderlichkeit der Scharnierachse beim Jugendlichen auf. Die Veranderung der Okklusion nach Bandabnahme mittels Gummiendgerat wird analysiert. Auf die Langzeitveranderungen der registrierten und analysierten Gruppe wahrend der Retentionsphase wird eingegangen.

To investigate whether orthodontic cases can fulfil gnathologic requirement, models of 10 adolescent patients (of the Department of Orthodontics at the University Dental Clinic, Graz) were mounted in an articulator at band removal and 2, 4 and 12 weeks and one year later. During this year the patients wore a gnathologic positioner. Using a condymeter, discrepancies between RCP and ICP in three spatial planes were measured and the spatial diagonal computed. Statistical analysis showed a clear reduction of the means of slide in centric during continuous wearing of the positioner, after 3 months, RCP and ICP being almost identical. After a further 7 months, during which the positioner was worn only at night, the amount of slide increased again slightly. The increase of the spatial diagonal was due to an increase of the sagittal and vertical slides whereas the lateral slide remained constant.

Vertikale Closing-Loops werden fur Zahnbewegungen in der festsitzenden Technik haufig verwendet. Untersucht wurden die gebrauchlichsten, namlich Stahl-, Chrom-Kobalt- und Titanium-Drahte. Aus diesen wurden vertikale Loops unterschiedlicher Hohe (6, 7 und 8 mm) mit 3 mm Schlaufendurchmesser und 1 1/2 Windungen geformt und mittels einer von uns angefertigten Versuchsanordnung auf ihre Kraftabgabe hin untersucht, die aus einer vertikal verstellbaren Federwaage zur Kraftmessung und einer Mesuhr zur Wegeinstellung bestand. Die pro 0,5 mm Aktivation ermittelten Werte wurden statistisch aufbereitet und fur jede Gruppe arithmetischer Mittelwert, Standardabweichung sowie Minimum und Maximum errechnet und in Tabellen zusammengefast. Die Ergebnisse zeigen eine eindeutige Abhangigkeit der Kraftabgabe von 1. Drahtlegierung, 2. Drahtdimension und 3. Loophohe, wobei der Einflus der Legierung sehr deutlich hervortritt. So reduziert sich die Kraftabgabe bei Verwendung eines Beta-Titanium-Loops auf ein Drittel der eines Blue-Elgiloy-Loops. Eine Anderung der Drahtdimension beeinflust deutlich die Kraftabgabe, wobei zum Beispiel ein .014-inch-Draht etwa ein Viertel der Kraft eines .016×.022-inch-Drahtes abgibt. Eine Verlangerung der Loopschenkel um 2 mm fuhrt zu einer Kraftreduktion von mehr als 50%. Durch die in Tabellen und Diagrammen zusammengefasten Werte wird es dem Kieferorthopaden ermoglicht, die fur die gewunschte Zahnbewegung optimale Kraft durch Anderung von Loophohe, Drahtdimension oder Drahtlegierung auszuwahlen.