Reliability of six methods of measuring convergence angle in posterior teeth for single PFM crown

Abstract

 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