ABSTRACT

The aims of this study were, 1. To determine the changes in soft tissues with Holdaway soft tissue analysis of Class II Division 1 mandibular retrognathie patients treated with upper two first premolars extraction, 2. To investigate the sexual differences between pre- and post-treatment values of boy and girl subjects, 3. To compare these values with the Holdaway soft tissue Turkish norms. The study group comprised the lateral cephalo-grams of 14 boys (mean age: 16.07+1.08 years) and 14 girls (mean age: 17.05+1.05 years) totally 28 (mean age: 17.00±1.06 years), skeletal Class II, dental Class II division 1 patients. Ten linear and 2 angular measurements were analyzed according to the definition provided by Holdaway on pre and post treatment radiographs. For statistical evaluation paired samples t-test and student t-test were performed. Soft tissue subnasale to H line, H angle, upper lip sulcus depth, skeletal profile convexity and upper lip strain measurements decreased and nose prominence, upper lip thickness and soft tissue chin thickness measurements increased during treatment period. Statistically significant sex differences were only found in nose prominence and H angle measurements between pre- and post-treatment values. In the comparison of these values with Holdaway soft tissue Turkish norms, soft tissue facial angle, nose prominence, soft tissue subnasale to H line, basic upper lip thickness, upper lip thickness and H angle measurements become closer to the Turkish norms. All changes were desirable for improvement of patients' soft tissue profile with extraction of upper two first premolars. The results of this study indicated that, generalizations concerning the negative effects of extraction compensations treatments on the profile of Class II Division 1 mandibular ret-rognathie patients are not true. It is necessary to investigate this difference in further investigations, using the parameters for soft-tissue analysis, need to be repeated with a larger sample.