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Inhibitory mechanisms contribute to directional tuning in primary visual cortex, and it has been suggested that, in the primate brain, the middle temporal area (MT) inherits most of its directional information from primary visual cortex (V1). To test the validity of this hierarchical scheme, we investigated whether directional tuning in MT was present upon blockade of local γ-aminobutyratergic (GABAergic) inhibitory mechanisms. Direction selectivity during the initial 50 ms after response onset was abolished in many MT cells when the local inhibitory network was inactivated whereas direction selectivity in later response periods was largely unaffected. Thus, direction selectivity during early response periods is often generated autonomously within MT whereas direction selectivity during later response periods is either inherited from other visual areas or locally mediated by mechanisms other than γ-aminobutyric acid type A receptor (GABAA.) inhibition. GABAergic inhibition may also mediate contrast normalization. Our data suggest that GABAA inhibition implements a local direction-selective static nonlinearity, rather than a full normalization in MT. These findings put constraints on strict hierarchical models according to which MT performs more complex computations based on local motion measurements provided by earlier areas, arguing for more distributed and independent information processing. [ABSTRACT FROM AUTHOR]

Aim: The success of rapid maxillary expansion is hard to predict in patients from the age of 20. There are as yet no reliable parameters enabling us to define success or failure a priori. The aim of this study was thus to use micro-CT techniques to quantify suture morphology three-dimensionally, and investigate its relation to age., Material and Methods: The morphology of the midpalatal suture was evaluated by documenting 28 human-palate specimens from individuals aged 14-71 using computed tomography. The software AMIRA 3.00 was used for 3D (three-dimensional) reconstruction of the datasets. Sutural morphology was quantified and examined for age-dependent morphological characteristics with the software Image Tool 3.00. To that end, the specimens were assigned to three age groups (< 25 years, 25 years to < 30 years, >/= 30 years) and the following parameters were considered: obliteration index in the frontal plane, and suture length, linear sutural distance, and interdigitation index in the horizontal plane, as well as bone density (BV/TV [%]) in the sagittal plane., Results: Significant differences between age groups were only found for bone density in sagittal dimension. The middle-aged group exhibited the highest bone density (53.2%). In comparison to that group, bone density was significantly lower in the youngest and the oldest age groups. The mean obliteration index exhibited substantial inter-individual variation, was generally low, and did not correlate with chronological age. The extent of interdigitation was independent of age., Conclusions: The necessity for surgical weakening can neither be explained by sutural interdigitation increasing with age nor by a higher obliteration index. Sutural bone density (hence the fracture resistance increasing with age) seems to be the parameter limiting conservative RME.

Aim: Since its introduction in dental radiology in 1998, cone-beam computed tomography (CBCT) has found increasing acceptance in clinical routine. The aim of this study was thus to evaluate this imaging modality from an orthodontic point of view., Materials and Methods: Two systems formed the basis of this investigation: the NewTom 9000 (NewTom Germany AG, Marburg, Germany), in use at the University Medical Center Hamburg-Eppendorf since October 2002, and the mobile Arcadis Orbic 3D system (Siemens Medical Solutions, Erlangen, Germany), which was introduced in February 2005. Two independent examiners evaluated a total of 68 NewTom and 15 Arcadis Orbic 3D images involving orthodontic indications. The images were categorized according to their indications and diagnostic value assessed according to a predefined and quantifiable protocol. Information obtained from the CBCT was also compared to that gleaned from conventional radiographs., Results: The indication for the NewTom images in cleft patients as well as for all Arcadis Orbic 3D images was considered justified. The osseous morphology of the cleft and position of osteosynthetic screws and plates were particularly well visualized. CBCT implementation in cases of tooth impaction or for assessing third molars was considered justified, although its value was judged differently by the two examiners. CBCT did not provide more information than conventional imaging regarding cartilaginous joint structures., Conclusions: In complex orthodontic cases in which 3D imaging is mandatory, CBCT is the method of choice. Furthermore, in cleft patients and those undergoing combined orthodontic and maxillofacial therapy, CBCT proved advantageous, providing more information than conventional images.

Objective: Conventional therapeutic approaches to correct ankylosed anterior teeth in infraposition require compromises involving esthetics and function. The combined approach of distraction and early orthodontic fine adjustment, not yet established as a routine, promises better results concerning the bone conditions and gingival development., Case Histories: Both female patients had suffered a trauma to the front teeth during early mixed dentition resulting in ankylosed central incisors in infraposition. At the ages of 14 years and 2 months and 15 years and 2 months, respectively, we carried out segment distraction by means of a bone-supported internal distractor followed by orthodontic fine adjustment after having shortened the consolidation phase. Both ankylosed front teeth could be successfully aligned, leading to an increase in bone and harmonization of the gingival margin in the dental arch. At ten and 14 months after the conclusion of treatment, we observed only few deviations in the dental situation compared to posttherapeutic findings., Conclusion: From a functional and esthetic point of view, therapy involving combined orthodontics and surgery is superior to conventional therapy. Orthodontic fine adjustment should be considered as a continuation of the distraction procedure.

352 children radiologically identified with asymmetry in the occipito-cervical region were assessed on a number of myofunctional measures. In all children an orthopedic examination was conducted including a functional test of the upper cervical spine and the iliac joint, the postural test by Matthiass, as well as gait analysis. During a second examination the orofacial myofunctional status was recorded. In general, about 70% of the children revealed orofacial myofunctional disorders. Correlational analysis was conducted in order to determine whether specific myofunctional variables were associated with postural and orthopedic alterations. A weak body posture correlated statistically significantly with all assessed myofunctional variables. On the other hand, all orthopedic items correlated significantly with a reclined head position. A blockade of the iliac spine correlated significantly with persistent habits, articulation disorders and tongue dysfunction, whereas functional asymmetry of the upper cervical spine correlated significantly with incompetent lips. A finding of at least five statistically significant correlations within each orofacial variable underlined the complex symptomatology of myofunctional disorders, so that consideration needs to be given to adequate treatment approaches. The data generated by the present study stress the importance of early interdisciplinary screening in children to ensure a physiological development of the orofacial region and the still growing vertebral column. To help understand the complexity of symptoms influencing orofacial development, an explanatory model of the "interactive functional box system" is given.

Background: Rapid maxillary expansion (RME) is a therapeutic orthodontic option with a long history, and there are many reports in the literature reporting widely divergent results concerning the appliance efficacy and many different treatment protocols. We aimed to evaluate the treatment protocols and clinical experiences with RME via a national inquiry of orthodontists to identify the status quo of RME in clinical daily routine., Method: Within the framework of an anonymous questionnaire, 2003 orthodontists and members of the German Orthodontic Society (DGKFO) were asked to report on their clinical experiences with RME. The standardized questionnaire covered clinical indications, dentition period at the time of insertion, mode of activation, retention time, observed side effects, and the reasons for requiring surgical assistance., Results: The data from 487 questionnaires could be evaluated. The only indication for RME named by a large majority of responders was transversal maxillary deficiency. The average extent of the transversal deficiency amounted to 5.29 +/- 2.25 mm (median 5 mm). Most orthodontists (87.7%) employed RME in the permanent dentition of adolescents; it was significantly less frequently applied in the primary dentition or adults. Answers regarding the mode of activation varied greatly. The most frequent mode of activation was "1-2 activations a day" independent of the dentition period. 64.5% of the orthodontists reported buccal tipping of the anchorage teeth. No correlation was detected between mode of activation, time of insertion and observed side effects. 60% of the orthodontists reported a retention period of between 3 and 6 months (median 4.5 months). With an average age of 19.28 years, 79.3% assessed chronological age as a limiting factor for conventional RME. It was not possible to identify a homogeneous diagnostic procedure for the indication of surgical assistance., Conclusions: Although RME has a long clinical history, no standardized treatment protocols exist. Randomized clinical trials are necessary to make clear-cut clinical recommendations on the use of RME, as required by the tenets of evidence-based medicine and quality assurance.

The aim of stimulating plate therapy in patients with trisomy 21 is to correct orofacial dysfunctions and prevent the establishment of subsequent morphological characteristics such as protrusion of the incisors and pseudoprognathia. This study investigated the effectiveness of this type of therapy in improving skeletal traits of patients with Down syndrome. The lateral cephalograms of 22 consecutive juveniles with Down syndrome, whose orofacial dysfunctions had been successfully treated with a stimulating plate according to Castillo Morales in infancy (17 months +/- 24 months), were examined 136 months on average (minimum of 78 months, maximum of 231 months) after initiation of treatment. In 16 of the 22 patients, the anomaly-typical bialveolar protrusion of the anterior teeth was diagnosed. The cephalometric results indicated larger values of cephalometric parameters concerning cranial base and maxilla, and markedly larger mandibular cephalometric values when compared to untreated children with Down syndrome. These results show that a stimulating plate may not always be indicated in patients with Down syndrome with a skeletal Class III pattern and minor orofacial findings.

Proteus syndrome is a rare condition that involves atypical growth of the bones, skin and head and a variety of other symptoms. Only a few authors have reported on the craniofacial manifestations so far. The authors present a case of a 7-year-old girl with Proteus syndrome in which the facial skeleton showed unilateral overgrowth. The analysis of the radiological evaluation revealed a bialveolar prognathism, a skeletal class III, a dolicocephalic growth pattern and a left convex face scoliosis. On the left side, the lesser wing of the sphenoid was elevated and the ethmoidal cell complex was hypertrophic. The left ramus and body of the mandible were enlarged. The asymmetric dental development with a precocious dental age on the affected side was the most striking feature on the panoramic view. Early diagnosis and therapy depend on clinical evaluation and imaging. Therefore, further evaluations on the craniofacial features of patients with Proteus syndrome are necessary in order to establish a list of characteristic symptoms.

From anatomic and functional aspects the stomatognathic system and the upper cervical spine are closely interlinked. Together with complex neuromuscular relationships, this gives rise to an important field of cooperation between orthodontics and orthopedics. The literature appeals for close interdisciplinary cooperation for patients with syndromes and for those with torticollis and scoliosis. Since orthopedic points of contact are obvious in these special cases, orthopedic aspects are now being taken increasingly into account in farther-reaching studies. With the rising popularity of manual medicine, these aspects are being recognized from the orthopedic point of view too in terms of functional correlations and are being increasingly debated at international congresses and in the literature. Although relevant publications were initially confined to studies of moderate scientific interest or case reports, potential correlations have undergone scientific investigation in recent interdisciplinary studies. Despite the many clinical studies, no unequivocal recommendation can be given for basic conditions under which an orthopedist is bound to be consulted on patients with orthodontic findings. This literature review is aimed at providing an introduction to this still hotly debated issue.

Background: Orofacial regulation therapy for children with Down's syndrome was introduced to Europe in Munich in 1978. Since then, many clinical studies have provided scientific evidence that this therapeutic approach enhances the orofacial function and facial appearance of children with trisomy 21. Only few long-term results have been published to date., Patients and Results: In the present study, 20 children with trisomy 21 were examined more than 12 years after starting treatment in infancy with a Castillo Morales stimulating plate. The follow-up examination showed that the improved orofacial appearance resulting from the early treatment had remained stable in most cases. Although the mechanical stimulus of the stimulating plate was absent during the follow-up period, some patients revealed a lip and tongue posture superior to that recorded at baseline., Conclusion: According to the results of the present study, the orofacial status in early childhood is decisive for the subsequent development of the orofacial region and the long-term stability of the achieved improvements: Children with a pronounced orofacial dysfunction showed a greater stimulation-plate-induced improvement than those with initially moderate orofacial findings. This observation was confirmed by the findings of the 12-year follow-up: Children with Down's syndrome and initially slight orofacial impairment displayed only slight improvements or unchanged findings.

Aim: In-vitro evaluation of an alternative method to the conventional acid etch technique., Material and Method: 240 human anterior and posterior teeth were divided into 16 groups of 15 teeth each. Group variables were: tooth type, enamel conditioning technique (Prompt L-Pop((R)): 3M Espe, Seefeld, Germany, or 37% phosphoric acid and bonding), adhesive (Transbond trade mark XT: 3M Unitek, Monrovia, CA, USA and ENlight((R)): Ormco, Orange, CA, USA), and testing procedure (shear and tensile bond strength). Upper lateral incisors and premolar brackets (Mini-Diamond((R)): Ormco, Orange, CA, USA) were used. Intergroup differences were analyzed by an analysis of variance. The enamel surface and the failure mode of debonded specimens were investigated with light and scanning electron microscopy., Results: Despite a tendency towards a higher bond strength after phosphoric acid conditioning, no statistically significant differences were found between the enamel conditioning methods. Statistically significant differences were recorded for the different adhesives: bond strength with Transbond trade mark XT was higher than with Enlight((R))., Conclusion: The single-step bonding agent sems to provide an acceptable bond strength between adhesive and enamel. No enamel fractures were detected. In vivo studies will be conducted to investigate the clinical performance of the new material.

Background: The quality of interdisciplinary cooperation is one of the most important factors in the success and long-term stability of treatment of patients suffering from orofacial dysfunctions. However, speech pathologists have criticized the poor communication and diagnostics at the time of referral and have requested a standardized diagnostic referral sheet with the aim of improving interdisciplinary cooperation., Diagnostic Referral Sheet: The diagnostic referral sheet presented here is based on the demands of speech pathologists focusing on myofunctional therapy and helps in initial assessment of the individual situation and necessary treatment. It is subject to continuous updating and coordinates the many medical disciplines involved on account of the complex pathology., Conclusion: The multidisciplinary diagnostic referral sheet, which is independent of treatment methods and compressed into one page, is aimed at contributing to quality assurance and to the improved documentation of orofacial dysfunctions.

Various removable and fixed orthodontic appliances were rated by interview and questionnaire by 42 myofunctional therapists in the Hamburg area with respect to their influence during myofunctional therapy. The Nance holding arch was given the most negative rating of all appliances covering the palate area. For the active plate, marking the rest position of the tongue by roughening the acrylic surface or by reproducing the palatal relief was considered beneficial. The quadhelix expansion device and Hyrax palatal expander were rated as unfavorable because of their positioning in the palatal area. Among the functional appliances, Fränkel's function regulator was given the best rating. Regular fixed appliances (brackets, bands) were not considered a disturbance. Habit reminders (plates and spurs) were given a very negative rating by ca. 80% of the therapists because they disturbed the myofunctional exercises and led to adaptive dysfunctions. Since many patients with dysfunction of the orofacial musculature undergo simultaneous myofunctional and orthodontic therapy, treatment planning and choice of orthodontic appliances should be carefully coordinated.

In order to evaluate current attitudes to early interceptive treatment, 2001 orthodontic offices in Germany were asked to fill in a questionnaire comprising the following topics: indication, appliances for the early correction of Class-III malocclusions, diagnostic records, duration, and benefits to overall therapy. Based on the 677 evaluable questionnaires, the following statistically significant conclusions could be drawn: 92.6% of the orthodontists see Class-III malocclusion as an indication for early treatment. Early treatment of severe crowding, diastemata, Class-II malocclusion, deep bite, increased overjet and impacted incisors was declined by most orthodontists. The interceptive treatment of further malocclusions was controversially discussed. Functional appliances (67.5%), in particular the Fränkel III (47.3%), were dominant in correction of Class-III malocclusions. Typical orthodontic records relating to early interceptive treatment include panoramic radiographs, lateral headfilms, photos and dental casts. 2.5% of the orthodontists routinely take a hand-wrist radiograph. Although recently published studies support the use of facial masks in theory, they are rarely used in practice. To what extent early interceptive treatment of Class-III malocclusion influences the overall treatment is the subject of further studies.