Normal faciolingual inclinations of tooth crowns compared with treatment groups of standard and pretorqued brackets.

Faciolingual inclinations of tooth crowns were measured on plaster casts of normal occlusions and posttreatment orthodontic models of treated cases. Normal anatomic occlusion, standard edgewise and Roth bracket groups of 10 subjects were examined for a change in torque values. On study models, crown inclinations of right and left central teeth to second molar in the upper and lower dental arches were measured to the functional occlusal plane and mean tooth inclinations were calculated. In normal occlusion group, upper central and lateral teeth inclined lingually, lower central teeth inclined slightly labially and lower lateral teeth inclined lingually but the standard deviations of mean values for upper and lower anterior teeth were high. Upper posterior teeth, from canine to molar, had a lingual inclination and lower posterior teeth had a progressively increasing lingual inclination from lateral to molar teeth. In treatment groups, upper central and lateral teeth had labial crown inclination and lower molar teeth had more lingual inclination as compared with the normal occlusion group. No significant variation was found between the mean torque values of standard and Roth treatment groups.

The effect of premolar extractions on tooth-size discrepancy.

The purpose of this study is to investigate whether the extraction of four premolars as a requirement of orthodontic therapy is a factor in the creation of tooth size discrepancies, and to determine whether any tooth extraction combinations create more severe discrepancies. The study is carried out on the pretreatment dental casts of 50 patients with malocclusions. The dental casts were selected according to the main criteria. No tooth-size discrepancy between the mandibular and maxillary dental arches should exist before treatment. Pretreatment mesiodistal dimensions of mandibular and maxillary teeth were measured, recorded on a computer program, and subjected to Bolton's analysis. Hypothetical tooth extractions were performed on each patient by the following combinations: all first premolars, all second premolars, upper first and lower second premolars, and upper second and lower first premolars. The resultant measurements were again subjected to Bolton's analysis to see whether a tooth-size discrepancy had been created. The results were evaluated statistically by the use of paired samples t test. The difference between the pretreatment and postextraction Bolton values was found statistically significant for the first premolar extraction and insignificant for the others. The removal of the four first premolars created the most severe tooth-size discrepancy, whereas the extraction of all four second premolars created fewer discrepancies and the smallest range in the size of discrepancies. The results of this study indicate a new point of view to the question of which teeth to extract when evaluated for tooth size aspect only.

Treatment of a Class I malocclusion with maxillary insufficiency and anterior crossbite: a case report.

A patient who had a Class I malocclusion with maxillary insufficiency and anterior crossbite is described. A 14-year-old girl with limited growth potential had an impacted permanent maxillary canine. The permanent mandibular first molars had been extracted previously. Treatment included extraction of the maxillary first premolars and comprehensive edgewise orthodontic therapy.

[Orthodontic treatment in a cleft palate-cleft lip case with severe maxillary collapse]. / Siddetli maksiller darligi olan bir dudak-damak yarigi olgusunda ortodontik tedavi.

The cleft lip and palate cases are the most frequently seen congenital deformities. Retardation of the maxillary development and collapse are the most significant characteristics in these cases. It is aimed to correct the functions like mastication, deglutition and speech which were disturbed due to anatomic deficiency and to obtain an acceptable occlusion and esthetics, by means of the therapy. As much as the preoperative orthopedic procedures applied just after the birth, the orthopedic and orthodontic appliances used in mixed and permanent dentition periods affect the prognosis in these cases. The purpose of the treatment in permanent dentition is to correct the malocclusion and to prepare the dentition to prosthetic restorations. In this article the orthodontic treatment of a case in permanent dentition, with cleft palate and lip characterized with severe maxillary collapse will be presented.

[Comparison of lower incisor positions after treatment and in postretention period, in Cl. I cases treated with Begg and Edgewise techniques]. / Begg ve Edgewise ile tedavi edilen sinif I olgularda tedavi sonu ve post retansiyon döneminde alt keser konumlarinin karsilastirilmasi.

The lower incisor positions have an important role in obtaining optimum occlusion and esthetics with orthodontic therapy. The aim of this study is to evaluate in longterm, the lower incisor positions of class I anterior crowding cases which were treated with Begg and Edge wise techniques. For this purpose lateral cephalometric radiographs of 20 Edge wise and 11 Begg cases which were treated by extraction of the four first bicuspids are evaluated. In all the cases T to NB (mm) T to NB (angle) and IMPA parameters examined before treatment, just after active therapy and in an average of 5 years postretention period. In cases which were treated with Begg mechanics, statistically important improvement is found in IMPA values after treatment. Lower incisors were stable in postretention period and there were no statistically significant differences when we compared the "after treatment" and "postretention" incisor positions in both treatment groups.

[Frankel III appliance]. / Frankel III apareyi.

FR III is a functional regulator appliance developed by Professor Rolf Frankel. This appliance is used in the treatment of Class III malocclusions. Optimum treatment results can be achieved when the appliance is used in the early mixed dentition period. The restricting effect of the buccinator and orbicularis oris muscles on maxillary skeletal development is prevented by means of lip pads and vestibular shields, thus maxillary development is stimulated. In this article philosophy, construction and clinical management of the FR III appliance will be described and two of our patients which are treated with this appliance will be presented.