ZusammenfassungZahn- und Kieferfehlstellungen gehören zu den häufigsten Mundgesundheitsbeeinträchtigungen beim Menschen. Der vorliegende Beitrag gibt eine Übersicht zu deren Ursachen, Häufigkeit und Folgen. Er zeigt die präventiven und kurativen Möglichkeiten kieferorthopädischer Behandlungen auf und gibt Informationen zu deren rechtlichen Rahmenbedingungen in Deutschland. Inanspruchnahme und Qualität der kieferorthopädischen Versorgung werden im internationalen Vergleich dargestellt.Bei den Ursachen für Zahn- und Kieferfehlstellungen spielen genetische, epigenetische, funktionelle und umweltbedingte Faktoren eine Rolle, die individuell meist nicht eindeutig feststellbar sind. Bisher zeigen nur kleinere Querschnittsstudien, dass bis zu 80 % der Kinder in Deutschland betroffen sind. Essen, Trinken, Kauen, Sprechen und Atmen können beeinträchtigt sein, die Neigung zu Parodontalerkrankungen sowie Überlastungsschäden von Kiefergelenk und Kaumuskulatur sind erhöht. Bei einer Proklination der oberen Schneidezähne steigt die Gefahr von Frontzahntraumata. Fehlstellungen können zudem negative psychosoziale Folgen oder Einschränkungen der Lebensqualität zur Folge haben. Kieferorthopädische Behandlungen leisten in Kooperation mit anderen (zahn-)medizinischen Fachdisziplinen einen wichtigen präventiven bzw. kurativen Beitrag zur Verbesserung der Mundgesundheit, der Allgemeingesundheit und der Lebensqualität.Die Kieferorthopädie bietet ein erhebliches Potenzial für die Stärkung der zahnärztlichen Prävention im Gesundheitswesen, zumal die gesetzliche Krankenversicherung (GKV) eine breitflächige Versorgung der Bevölkerung mit kieferorthopädischen Leistungen auf international anerkanntem, hohem Niveau ermöglicht. Um die Prävention weiter zu verbessern, wird die Einführung eines kieferorthopädischen Screenings im 7.–8. Lebensjahr als systematische Vorsorge empfohlen.

Malocclusions are among the most common human diseases impairing oral health. The present paper gives an overview on their etiology, prevalence, and consequences. It further presents the corrective and preventive potential of orthodontic treatment and gives information on the treatment-associated legal framework in Germany. The use and quality of the orthodontic health service will be described in the international context. The etiology of malocclusions has genetic, epigenetic, functional, and environmental components, which can seldomly be differentiated on the individual level. Previous small, cross-sectional studies show that up to 80% of children in Germany are affected. Eating, drinking, chewing, speaking, and breathing may be impaired and the predisposition for periodontal disease and overuse injuries of the temporomandibular joint and the masticatory musculature increase. A proclination of the upper incisors increases the risk for dental trauma. Furthermore, malocclusions may have negative psychosocial effects and impair quality of life. In cooperation with other dental and/or medical disciplines, orthodontics make positive preventive and curative contributions to oral health, general health, and quality of life. Against this background, orthodontics has a substantial potential for the enhancement of dental prevention in healthcare. This is especially true as the German social health insurance (GKV) allows for a widespread orthodontic treatment coverage of the population at an internationally accepted, high-quality level. To further improve prevention, the implementation of a systematic orthodontic screening at the age of 7-8 years in the form of a systematic preventive measure is recommended.

ZusammenfassungDer „Extrathorakale Luftraum“ findet im klinischen Alltag des Kieferorthopäden sowohl bei der Fallplanung als auch bei der Therapie kaum Beachtung. Ziel dieses Beitrages ist es deshalb, Anatomie, Historie, unterschiedliche Definitionen, bildgebende Verfahren sowie Simulationstechniken des extrathorakalen Luftraumes darzustellen. Ohne kritische Aspekte zu vernachlässigen, werden therapeutische Maßnahmen mit möglichen Auswirkungen auf den extrathorakalen Luftraum, ausgewählte Studienergebnisse sowie interdisziplinäre Implikationen aufgezeigt, auch um die Relevanz des Themas für den Kliniker hervorzuheben.

BACKGROUND:The aim of this retrospective investigation was to evaluate the incidence of loss to pulp sensibility testing (PST) of maxillary front teeth after paramedian (3 to 5 mm away from the suture) orthodontic mini-implant (OMI) insertion in the anterior palate.METHODS:A total of 284 patients (102 males, 182 females; mean age was 14.4 years (±8.8) years at time of OMI-Insertion) with a total of 568 OMIs (1.7 mm diameter, length 8 mm) were retrospectively investigated. A binomial regression analysis was performed to explore covariates, such as age, gender, inclination of upper central incisors, dentition status and insertion position of OMIs that could have contributed to loss of sensibility. Statistical significance was set at p < 0.05.RESULTS:Loss of response to PST was encountered during retention in 3 out of 284 patients and the respective OMIs had been placed at height of the second rugae (R-2). Affected teeth were a right canine, a left lateral and a left central incisor. Subsequent root canal treatment was successful. Results of the binomial regression analysis revealed that the covariate insertion position (R-2) of OMIs (p = 0.008) had statistically significant influence on loss of response to PST.CONCLUSIONS:(1) Although there was no radiographic evidence for direct root injury, the proximity of the implants to the anterior teeth was nevertheless statistically related to loss of PST. (2) In all cases of PST loss OMIs were inserted at the second rugae. Therefore OMIs should be placed either more posteriorly, at the third rugae or in the median plane. (3). Loss of PST was not increased for patients with palatal OMI (0.18%) compared to samples without OMI (0.25%).

The aim of this retrospective study was to measure tooth and crowns axes of canines, first and second bicuspids of orthodontically untreated subjects with near normal occlusion to: 1. Define norms and reveal potential gender differences and 2. Discuss implications of the findings for orthodontics.

Primary surgery in patients with complete unilateral and bilateral cleft lip and palate restricts transverse and sagittal maxillary growth. Additional surgical maxillary advancement might become necessary after completion of growth. The aim of this study was to determine the extent of maxillary deficiency at an early stage during the transitory dentition, and to identify factors that might indicate the need for a later maxillary advancement.

Introduction: In this study, we aimed to assess the ability of a new viscoelastic finite element method model to accurately simulate rapid palatal expansion with a miniscrew-supported hybrid hyrax appliance. Methods: A female patient received 3-dimensional craniofacial imaging with computed tomography at 2 times: before expansion and immediately after expansion, with the latter serving as a reference model for the analysis. A novel approach was applied to the finite element method model to improve simulation of the viscoelastic properties of osseous tissue. Results: The resulting finite element method model was a suitable approximation of the clinical situation and adequately simulated the forced expansion of the midpalatal suture. Specifically, it demonstrated that the hybrid hyrax appliance delivered a force via the 2 mini-implants at the center of resistance of the nasomaxillary complex. Conclusions: The newly developed model provided a suitable simulation of the clinical effects of the hybrid hyrax appliance, which proved to be a suitable device for rapid palatal expansion. (Am J Orthod Dentofacial Orthop 2013;143:426-35)

Objective: The aim of this study was to investigate and compare the skeletal treatment outcome in patients aged 18 years with complete bilateral cleft lip and palate who received their complete treatment until early adulthood in two centers with different treatment protocols.Design: Twenty-two patients (13 from center 1, nine from center 2) with complete primary bilateral cleft lip alveolus and palate were included. Lateral cephalograms were studied at the ages of 10 (T-1), 15 (T-2), and 18 (T-3) years. Sagittal, vertical, and dental parameters were measured and compared. Statistics included tests for normal distribution, a three-way analysis of variance, and bilateral t tests for associated and nonassociated random samples with the significance level p < .05.Results: Data from center 1 showed a significant decrease in ANB, WITs appraisal, and NL-NSL and an increase in Ui/NL. Data from center 2 showed a significant increase in SNB; a decrease in ANB, WITs appraisal, and ML-NSL; and an increase in Ui/NL. The intercenter comparison of means at the end of treatment (T-3) revealed no significant differences for any parameter, despite few significant differences at T-1 and T-2.Conclusion: The different treatment concepts did not yield significant differences in treatment outcome at early adulthood. All final skeletal parameters were comparable to those of patients without a cleft. These results indicate treatment execution may be more important than the treatment protocol.

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. (Am J Orthod Dentofacial Orthop 2011;139:465-9)

A previous Overview described suitable sites for vestibular miniscrew insertion.1 Although these locations are commonly used in orthodontic applications because of their ease of access, the interradicular spaces are limited by the proximity of neighboring roots (Fig. 1), presenting the following problems: • Risk of damaging the roots or the periodontium. • Possibility of miniscrew-root contact resulting in early screw failure. • Risk of screw fracture during placement, due to the narrower miniscrew dimensions needed for interradicular positions. • A loss rate as high as 25%.2 These risk factors can be avoided by using “rootless areas” such as the hard palate, the maxillary tuberosity, or the portions of the zygomatic arches adjacent to the maxilla. The tuberosity cannot be regarded as entirely safe, since unerupted third molars or thick layers of gingiva may prevent successful insertion3 (Fig. 2). Insertion into the inferior portion of the zygomatic arch carries the risk of perforating the maxillary sinus.4 Therefore, the only safe alternatives to buccal miniscrew placement are in the palate. In the mandible, where lingual screw insertion is associated with higher loss rates,5 the mentalis region is better suited for miniscrews and miniplates.6 In the maxilla, the hard palate appears to be an ideal insertion site. While the anterior palate definitely offers sufficient bone, consensus has yet to be reached regarding the minimal amount of bone required to avoid penetration into neighboring anatomical structures. Liou and colleagues suggested 2mm,7 Poggio and colleagues

OBJECTIVE:By metrically analyzing orthopantomograms, we aimed in this study to retrospectively investigate whether maxillary premolars used as anchoring teeth during molar distalization with pendulum appliances would reveal inhibited root development.PATIENTS AND METHODS:The upper molars were distalized with a modified pendulum appliance (Pendulum K) in 36 adolescents (14 males, 22 females, mean age 12.3 years). Mean treatment period was 19.5 weeks. Orthopantomograms of each patient were taken at the start (time point T1) and after completion of molar distalization (time point T2). The enlargement of the posterior region was ascertained individually quadrant by quadrant for each radiograph, followed by measurement of the vestibular tooth lengths of the premolars whose root development was for the most part not yet complete. To assess further root development in the premolar region, the differences were calculated between tooth lengths at the start and end of treatment.RESULTS:During treatment with the pendulum appliance a general increase in tooth lengths in the anchorage region was observed (1.37 +/- 1.70 mm, p<0.0001). Differentiated by dental age, we noted increases in tooth lengths of patients with second molars in the budding stage (patient group PG 1: 0.93 +/- 1.37 mm, p<0.0001) as well as of patients with fully-erupted second molars (patient group PG 2: 1.81 +/- 1.88 mm, p<0.0001). Both groups demonstrated greater increases in the second premolars than the first premolars; the increases group-wise were larger in PG 2 than PG 1. However, both the group comparison (PG 1 versus PG 2) and the side comparison (right versus left) (differentiated into first and second molars) showed no statistically relevant differences. Visual assessment of the radiographs revealed no evidence of treatment-related root deviations.CONCLUSION:A highly complex system of forces acts on the anchoring teeth during molar distalization with the conventionally-anchored Pendulum K. However, the Pendulum K appliance's specific biomechanics make it possible to transfer the reactive forces and moments to the anchorage unit so that they remain within the physiological range, allowing uninhibited premolar root development. This also applies after completed eruption of the second molars, when the treatment period and hence duration of exposure to the active and reactive forces and moments arising during molar distalization are comparatively increased.