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Objectives: The goal of the following study was to quantify facial soft-tissue asymmetry in patients with pronounced skeletal malocclusion anomalies before and after orthodontic treatment combined with orthognathic surgery. In addition, the facial attractiveness of these patients was rated by dental specialists and laypersons both before and after treatment based on the three-dimensional (3D) data., Patients and Methods: An optical sensor was used to noninvasively capture the 3D facial surface data of 60 adult patients including two groups of 20 patients with skeletal Class II or III anomalies and a control group of another 20 subjects with Class I relationships. Facial surface asymmetries were evaluated immediately before the surgical procedure and 1 year thereafter. In addition, subjective ratings of facial attractiveness were obtained based on a questionnaire from orthodontists, maxillofacial surgeons, and laypersons., Results: No differences in facial soft-tissue asymmetry were observed between the Class II and III patients either pre- or postoperatively, but asymmetry was found to be more pronounced in the skeletal malocclusion groups than in the Class I control group both pre- and postoperatively. The subjective ratings of facial attractiveness by the various rater groups yielded more favorable results for the post- than preoperative patient images, reflecting differences that reached overall statistical significance., Conclusion: Quantitative analysis of facial soft-tissue asymmetry and calculating a cutoff value allowed us to distinguish patients with skeletal malocclusion from a control group solely on the basis of asymmetry. Combined regimens of orthodontic treatment and orthognathic surgery go some way in reducing asymmetry toward the levels seen in untreated control subjects, while the asymmetry pattern characteristic of this type of malocclusion will persist. Nevertheless, the asymmetry reduction is noticeable enough to result in more favorable ratings of attractiveness.

Background and Aim: Surgically-assisted rapid maxillary expansion is a frequently employed procedure for expanding the maxilla in adults to treat pronounced transversal discrepancies of the upper jaw. Several studies have shown how the position of the anchorage teeth changes due to SRME. However, there is little detailed information available on the transversal movement of each tooth, its change in inclination and subsequent alterations of the arch length, width and sagittal arch form., Material and Methods: In our study we investigated those changes in 31 patient casts after SRME, following the active phase, and after a 3-month retention period whereby the Hyrax appliance remained blocked in situ. The casts were examined using a 3-dimensional reflex microscope., Results: After active treatment the second molars moved 28% less than the amount of total expansion. At 9.6 degrees (first bicuspid) and 11.6 degrees (first molar), the anchorage teeth were also more buccally tipped than the second molars (7.4 degrees ). Unlike with conventional maxillary expansion, the measured increase in arch length here corresponded to the amount of anchorage teeth expansion. The sagittal arch decreased significantly during the retention phase in those teeth in front of and behind the anchorage teeth. Three months later we found that only 68% of the original expansion had occurred in the canines and second molars. The inclination of the teeth decreased slightly but significantly. We observed an only temporary increase in the sagittal dimension after appliance activation. There was an average loss of 0.83 mm at the end of the retention phase. Moreover, the anterior dental arch length only experienced a 50% increase in space over the expansion achieved initially., Conclusion: To minimize relapse rates in cases of severe crowding, we recommend that the canines and second molars be included in the appliance.

Objective: In this study we aimed to identify the reasons why cervical headgear treatment fails to induce bite opening or clockwise rotation of the mandible in the presence of a vertical growth pattern. In so doing, we investigated the dental effects of headgear treatment relative to growth patterns., Materials and Methods: Records of 119 patients were analyzed, including casts and lateral cephalograms that had been obtained immediately before and after isolated cervical headgear treatment. Dental changes were determined relative to the SN line and a perpendicular line through point S. Inclusion criteria were: improvements in occlusal relationship of at least 4 mm in molar segments and treatment lasting at least 6 months. An orthodontic force of 3.5-4 N was applied in all cases through headgear featuring non-angulated outer arms. The headgear was worn for 14 hours a day during the active treatment phase. At the beginning of headgear treatment, patients were allocated into six groups according to y-axis values to quantify growth-related differences., Results: The upper first molar was moved an average of 1.3 mm distally, while the lower first molar was moved an average of 2 mm mesially. These movements revealed no differences in terms of growth patterns. We were not able to make representative findings pertaining to upper molar extrusion due to distal tilting and the measuring point's position. We used the lower molars' movements for analysis instead, which demonstrated mean downward changes of 5.1 mm in all groups. The vertical growth pattern groups presented smaller caudal movements in the upper and lower anterior segments than did those groups with horizontal growth pattern. The occlusal plane's inclination decreased more extensively in the vertical growth pattern groups than in those with a horizontal pattern (e.g. H2: -0.1 degrees ; V3: -2.3 degrees )., Conclusion: Our results suggest that while the upper molars extrude, the mandible rotates around the molars in a hypomochlion fashion in the presence of a vertical growth pattern, thus leading to bite deepening.

Background and Aim: Fixed functional orthopedic appliances used in 6 to 9 month-long treatments to correct distoclusion keep the mandible permanently in the therapeutically-desired protruded position. The principal aim of this approach is to achieve an increase in length of the lower jaw by stimulating mandibular growth. Ideally, adaptive mechanisms in adolescents and young adults result in condylar remodeling. Alternatively, however, therapeutically-undesirable alterations in the condyle position within the articular fossa may also occur. Thus the aim of this magnetic resonance imaging (MRI) study was twofold: 1) to verify the effects that the treatment with a fixed functional orthopedic appliance used to correct distoclusion has on the topographic relationship of mandibular condyle and glenoid fossa, and 2) to analyze morphologic changes in the condyle., Patients and Methods: Treatment progress in 20 patients was monitored by MRI at four defined points in time. Visual inspection and metric analysis were performed in three planes (axial, frontal, parasagittal) shown on the MRIs. 3D-reconstruction of the condyle surfaces based on the MRI data sets at hand was done in selected cases., Results: Upon assuming the therapeutically-desired position, the condyles were caudally and ventrally displaced from their centric position within the fossa. At the end of treatment, they had returned to their original position. When assessed laterally, statistical analysis revealed no significant differences between the joints on the right and left sides. Neither the anterior nor posterior joint space among all 40 joints exhibited significant changes in width compared to the baseline findings. Visual inspection in the axial, frontal, and sagittal planes revealed changes in the exterior form of 31 of the 40 condyles analyzed. On the whole, while morphologic changes were observed in all three planes, they were most marked in the axial plane. Metric analysis of the 2D-MRIs, on the other hand, revealed no significant changes in width, depth, or height in the plane in question. This is why we reconstructed the condyle structure three-dimensionally on a trial basis. For purposes of analysis, we super imposed the reconstructions of the condyle surfaces at the various control points on each other. By processing the data in this manner, an alternative approach for evaluating morphologic changes was created. CONCLUSIONS AND PROSPECTS: In patients treated with a rigid, fixed functional orthopedic appliance (FMA) for skeletal Class II malocclusion, both joints returned to a physiologic condyle-fossa relationship post-treatment. The improved occlusion was not achieved at the price of unphysiologic repositioning in the temporomandibular joint. Visual inspection suggested that morphologic changes in the condyle may have occurred as treatment progressed, but this was not confirmed by 2D metric analysis. However, by means of 3D-reconstruction of the condylar surfaces and their superposition, detailed visualization of adaptive mechanisms and their non-invasive evaluation in 3D may become feasible in clinical routine.

Subject: The present investigation deals with the questions of whether there is a typical craniofacial morphology in cases with cover-bite malocclusions, whether this type correlates with variation in population, and whether this growth pattern can be influenced by treatment with removable appliances., Patients and Method: The issue was approached by studying lateral cephalograms of 75 subjects (35 males, 40 females) divided into three groups of 25 subjects each: German cover-bite patients, Syrian cover-bite patients, and subjects with neutroclusion. Overall 125 lateral cephalograms were studied with 13 reference lines and 18 reference angles being taken into account. The data obtained were subjected to statistical analyses using the t-test to detect significant group differences., Results: The results revealed that there are characteristic features in cover-bite patients in comparison to subjects with neutroclusion and that these features are partly subject to interpopulation differences as well as to interindividual variations. With regard to orthodontic treatment the cover-bite craniofacial morphology is marginally influenceable.

The aim of the present study was to evaluate sagittal, vertical and transverse changes in canine position and a possible correlation with relapse of lower anterior crowding. From a sample with a long-term follow-up of 15.7 +/- 4.4 years after treatment, patients with a full dentition were enrolled in the study. Post-treatment and long-term follow-up casts of 117 patients were measured and statistically analyzed. A decrease in intercanine width was found between post-treatment and long-term follow-up records, with more lingual inclination of the mandibular canine axis in the transverse plane. There was a significant correlation between maxillary and mandibular canine inclination. Concomitant changes were an increase in lower anterior crowding and a decrease in mandibular intercanine width. Relapse of anterior crowding has a multifactorial etiology. The results of this study suggest a possible influence of the canines. Functional causes in particular might have a profound influence and should be considered during treatment planning.

The periodontal relevance of anterior and posterior crowding concerns 3 main aspects: 1. oral hygiene/plaque retention, 2. altered topography of gingiva, septum and orofacial alveolar bone and 3. periodontal therapy (scaling, root planing, regenerative approaches). These aspects are discussed with regard to the literature and to the author's own clinical and histological findings. Present-day knowledge suggests that the following positive periodontal effects can be expected from correction of orthodontic crowding: better access for oral hygiene, improved morphology of soft and hard periodontal tissues; future research has to substantiate the value of this benefit, simplified mechanical and surgical therapy (scaling, root planing, curettage), more favorable conditions for periodontal regeneration.

On the basis of various opinions expressed in the literature, "closed bite" is associated in particular with an impaired front-tooth relation. Applying Tonn's index, evaluation of the records (models and cephalograms) of 1,100 patients, however, yielded no evidence of changes in the width ratio of the front teeth with regard to Angle classes, growth type, axial inclination of the central upper incisors, interincisal angle, or overbite.

In our study of 107 patients, for whom data derived from clinical functional analysis, axiography and, in part magnet resonance imaging, were present, we were able to show that in routine orthodontic diagnosis the use of panoramic X-ray in the normal course of a general examination of the mandibular joint can also provide important indications of the presence of cranio-mandibular disorders. The panoramic X-ray revealed that in patients with Angle class II and front deep and open bite there were significantly mor changes in the form of the condyles. A definite morphologic finding of a retracted fovea pterygoidea was found frequently in patients with anterior disk replacement with or without reduction. Lastly, the panoramic X-ray showed that a change in form of the condyles, with in some cases a serious arthrosis, occurs significantly most frequent in patients with anterior displacement without reduction.

The posttreatment tissue profile changes that can be observed after treatment with the Herbst therapy were investigated in a class II malocclusion mixed dentition group. Profile photographs of two groups of 18 patients were compared. One group was treated with the Herbst appliance, the other served as an untreated control. The treated cases were retained by means of an activator after the active treatment period. After this retention period, new profile photographs were taken and compared to the controls. All treated patients displayed a significant improvement of the soft tissue profile at the end of the active treatment period. After retention a relapse tendency could be observed. Due to the large range of observed treatment effects, no correlation between soft tissue profile and skeletal changes could be found.

The clinical crown lengths of the incisors and first molars of 50 adolescents were measured on dental casts prior to and five to seven months following end of treatment and the differences were recorded. The patients were treated with fixed appliances for an average of 23 months. In addition, initial crown lengths were compared to those of ten children who were four years younger on average. Treatment time and objectives were recorded. Statistically significant differences were determined by means of the t-test. In order to test for correlations between treatment objectives, duration of treatment and change in clinical crown length, correlation analysis was used. The results were: clinical crown length increases physiologically from ten to 14 years of age by about 0.175 mm per year. During fixed appliance therapy in adolescents, the clinical crown length increases. This is accelerated when employing extrusive mechanics, whereas intrusive mechanics reduce this tendency. There is no evidence to suggest that the process is accelerated by the type of appliance.

In the context of a global examination of the effects of the activator therapy of Herren in class-II malocclusion, the position of the hinge axis points was studied in a group of 12 consecutive cases (9 boys and 3 girls). The hinger axis was recorded immediately before and in the course of the treatment, using a standardised recording method. After 1 mm change in occlusal relationship, the hinge axis points were located about 2 mm caudally of the tattooed zero point. When the change in occlusal relationship step by step had reached 3, 5 and 7 mm, and even after 6 months of retention, the hinge axis points had moved back by about 1 mm in a cranial direction, but remained still about 1 mm caudally of point zero. In a sagittal direction, a facial dislocation of about 1 mm was found no sooner than after a 6-months retention time. A study on reproducibility was used to ensure the statistical proof of these results.

With cephalometric measurements we investigated the morphology of the malocclusion "Open bite" from adults. The main of abnormality is the divergence of the jaw bases and the compensatory growth of alveolar bone in vertical direction. Under consideration of the best time for beginning of the treatment we give advice for the etiologically orientated therapy.

The detailed examination of the masticating apparatus of 18 skulls from the Middle Bronze Age in Pitten (Lower Austria) revealed numerous pathological findings of the teeth. Most remarkable were frequency and extent of dental abrasions. In addition to it, indications on inflammatory processes in the marginal parodontium were obtained, combined with partly immense formations of concrements on the surfaces of the teeth. The incidence of dental caries was relatively low. Abnormal positions of the teeth and pathological processes concerning the development of dentition as well as the eruption of the wisdom teeth could be observed repeatedly. Conclusions on insufficiences of the oral hygiene in this time follow especially from the concrement findings and from the inflammatory reactions of the marginal parodontium.