Reliability of six methods of measuring convergence angle in posterior teeth for single PFM crown Dr. Jalali H .,1 Dr. Hajmiragha H .,1 Dr. Bazrpour AH .2 Dr. Nokar S. 1 1 Assistant Professor, Department of Prosthodontics, School of Dentistry, Tehran University / Medical Sciences. Tehran, Iran. 2 Dentist. (Received 5 Nov, 2008 Accepted 9 May, 2009) Abstract Background and Aim : There are several methods of measuring Convergence Angle in posterior single PFM crown. The aim of the present study was to compare the reliability of these methods. Materials and Methods : This experimental study was conducted with twenty selected stone dies, numbered 1 to 20. The convergence angles were measured and recorded by five last year dental students using manual and computer assisted methods. The manual methods used were: 1. Photocopy machine, 2. Digital camera, 3. Analogue camera (photography), 4. Overhead projector the computer assisted methods were: 5. Scanner machine and 6. Microscope. Data were analyzed using One Way Random Effect, and SPSS version 11 statistical software. Results: Coefficient of reliability for methods 1 to 6 was 0.9981, 0.9988, 0.9986, 0.9991, 0.9957, and 0.9994 respectively. No significant difference was detected among these methods and all were found to be reliable. Conclusion : There were no significant differences among the methods evaluated. Moreover, all methods were found to be significantly reliable and can be used for measuring convergence angles. Key words : Reliability - Convergence angle - Axial wall inclination - Retention . Corresponding Author : Dr. Nokar S ., Assistant Professor, Department of Prosthodontics, School of Dentistry, Tehran University / Medical Sciences. Tehran, Iran. e.mail: noukarsa@sina.tums.ac.ir |
