ABSTRACT
The purpose of this investigation was to evaluate the effects of different growth patterns and treatment types on dentoalveolar structures in patients treated with fixed Edgewise mechanics and the extraction of four first premolars. A total of 41 patients with a mean chronological age of 14 years 7 months and skeletal age of 14 years 6 months were included in the study. The type of growth pattern was assessed as mesio- or hyper-divergent, and the treatment type as the use or non-use of headgear. The results were analysed by two-way analysis of variance (ANOVA). The decrease in overbite in the mesiodivergent group was statistically significant when compared with the increase in the hyper-divergent group (P < 0.01). Extrusion of the lower molar was observed in all groups, and a statistically significant difference was found between the mesio- and hyper-divergent groups (P < 0.05). Interaction between growth pattern and treatment type was not found to be significant for any variable. It can be concluded that premolar extractions and the use of headgear with fixed appliances does not significantly change the overjet, occlusal plane angle, upper and lower anterior dentoalveolar heights, upper posterior dentoalveolar height, or the inclination of the upper and lower incisors. The only significant changes were observed in overbite as a result of treatment mechanics and in lower posterior dentoalveolar height due to the growth pattern.
Subject(s)
Extraoral Traction Appliances , Malocclusion/therapy , Maxillofacial Development , Orthodontics, Corrective/methods , Tooth Extraction , Adolescent , Adult , Analysis of Variance , Bicuspid/surgery , Cephalometry , Child , Female , Humans , Male , Orthodontics, Corrective/instrumentation , Outcome Assessment, Health CareABSTRACT
The purpose of this study was to evaluate the effects of different growth pattern and treatment type factors on craniofacial structures in cases treated with fixed mechanics and premolar extractions. A total of 41 cases with a mean chronologic age of 14 years 7 months and skeletal age of 14 years 6 months was included in the study. These cases were treated with fixed Edgewise mechanics and with extraction of four first premolars. The growth pattern factor was assessed in two levels as mesiodivergent and hyperdivergent, and the treatment type factor was assessed as with and without headgear. The results were analyzed by two-way analysis of variance. In the assessment of differences between the two types of growth patterns at the end of treatment; the changes in N-ANS and N-M were found to be statistically significant (P <.05). In comparison of cases treated with and without headgear, changes in SNA and ANB angles were found to be statistically significant (P <.01). Interaction was found to be nonsignificant for all measurements. It was observed that treatment with fixed appliances and premolar extractions does not change significantly the growth pattern.
Subject(s)
Maxillofacial Development , Orthodontics, Corrective/methods , Tooth Extraction , Adolescent , Analysis of Variance , Bicuspid/surgery , Cephalometry/statistics & numerical data , Extraoral Traction Appliances , Hand/diagnostic imaging , Humans , Malocclusion, Angle Class I/diagnostic imaging , Malocclusion, Angle Class I/therapy , Malocclusion, Angle Class II/diagnostic imaging , Malocclusion, Angle Class II/therapy , Orthodontics, Corrective/statistics & numerical data , Radiography , Tooth Extraction/statistics & numerical data , Wrist/diagnostic imagingABSTRACT
This case report shows the effects of functional therapy at an early age in a severe Class II, division 1 malocclusion. Favorable changes in the profile and in the lip seal were achieved. The dental irregularity was treated by fixed appliances and extraction therapy. The patient and her parents were pleased with the final outcome.
Subject(s)
Malocclusion, Angle Class II/therapy , Orthodontics, Corrective/methods , Retrognathia/therapy , Bicuspid/surgery , Cephalometry , Child , Dentition, Mixed , Extraoral Traction Appliances , Female , Humans , Orthodontic Appliances, Functional , Tooth ExtractionABSTRACT
Posterior bite-blocks that are used in the early treatment of skeletal open bite, produce a forward and upward mandibular rotation by transmitting the masticatory muscle forces to the buccal dentoalveolar regions and preventing their vertical growth. Increasing the vertical dimension of the face artificially causes skeletal adaptations to occur not only in the dentoalveolar region but also in the other regions of the craniofacial complex. The affects of passive posterior bite-blocks, constructed in two different heights, were investigated for two treatment groups, in comparison to an untreated control group. Two treatment groups comprised of 25 growing patients, who had skeletal open bite and skeletal/dental Class I or Class II malocclusions, and one control group consisting of 14 growing patients were used. These groups were matched concerning their age, sex, and vertical and sagittal skeletal cephalometric and dental characteristics. Passive posterior bite-blocks of 5 and 10 mm heights were applied to the subjects of the treatment groups respectively for 18 hours per day. Untreated control subjects were observed for 7 to 9 months. The findings of this study revealed that the downward and backward mandibular rotation continued in the control group, increasing the lower facial height significantly, whereas in the treatment groups, the skeletal open bite was treated and the mandible rotated upward and forward. The increase of the height of the posterior bite-blocks had a significant effect on the anterior mandibular rotation and in the increase of the gonial angle.