Cephalometric evaluation of skeletodental and soft tissue changes after four premolar extraction treatment in patients with high angle class i malocclusion

The aim of this study was to evaluate the dentoskeletal changes of patients who had skeletal and dental Class I relationship with increased vertical pattern and were treated with four premolars extraction, by using cephalometric radiographs and to compare the results with non-treated control group who had similar craniofacial and dental patterns.A total of 88 lateral cephalometric radiographs taken before/after from the treatment and control groups whom were referred to Dicle University, Dental Faculty, Department of Orthodontics were used in the present study. In the treatment group, 24 young adult patients with Angle Class I malocclusion and SN-GoGn ? 35º who demonstrate crowding of 3.8 mm in the maxilla and 3 mm in the mandible were used. The records of 20 individuals that were not treated whom demonstrate Angle Class I malocclusion and SN-GoGn ? 35º served as our control group.The patients were divided into 2 groups as treatment and control groups. Skeletal, dental and soft tissue changes were measured on cephalometric radiographs that were taken before and after in treatment group. In the control group, same skeletal, dental and soft tissue parameters that were taken at the beginning of control and at the two years were investigated. For statistical analysis, paired sample t test and independent t test were used for intra and intergroup comparison, respectively.Although statistically significant changes were detected in treatment group, clinical importance of these parameters is questionable. Our results do not demonstrate an evident anterior rotation of the mandible.The inefficient anterior rotation of the mandible resulted from the mandibular molar extrusion in treatment group.Additional extrusion preventing mechanics to decrease the vertical dimension and mandibular anterior rotation are needed.Key words: 1. Angle Class I Malocclusion 2. Extraction Treatment 3. Increased Vertical Dimension 4. Cephalometric Evaluation.