Effect of Using Application “PrepLooker” as an Educational Media in Undercut & Convergence Angle of Crown Preparation of 4 th Year Dental Student KKU

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Suwadee Aerarunchot
Thanatta Songphaeng
Ratirat Chotipanvidhayakul
Nounprang ฺBoonpongsathian
Kanda Runapongsa Saikaew
Prawit Buayai


The undercut and convergence angle are the factors affecting retention and resistance to the crown, but the accuracy of its visual estimation has not been determined. It is difficult for the inexperienced dental students to evaluate the undercut and convergence angle; therefore the failures of the preparation occur. The objective of this study was to compare the average score of the test between before and after using the application, PrepLooker. The test is about evaluating the convergence angle and undercut in the abutment that prepared for the crown in the 4th year dental student. This study conducted an experiment with twenty of the 4th year dental students who did the tests before using the application. The tests were the ten artificial teeth prepared to be the abutments for the crown, with convergence angle ranging between 0-20 degrees and more than 20 degrees and with and without undercut. All of the abutment teeth were checked for the validity by three expert sand checked for reliability by 6 6th year dental student. After that, the dental students studied how to determine and estimate undercut and convergence by using the application for 2 times, 60 minutes per time. Then the 4th year dental students did the post-test without using the application. The average scores before and after using application were compared with Paired T-test (= 0.05). Significantly increase in the average scores of the test was found (P < 0.001). This study result showed that the application can assist the 4th year dental students to understand undercut & convergence angles of the crown preparation. The average scores after using the application were increased significantly by 66.67%. In the future, the application would be developed for actual usage in clinical situations.


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Aerarunchot S, Songphaeng T, Chotipanvidhayakul R, ฺBoonpongsathianN, Runapongsa Saikaew K, Buayai P. Effect of Using Application “PrepLooker” as an Educational Media in Undercut & Convergence Angle of Crown Preparation of 4 th Year Dental Student KKU. KDJ [Internet]. 2021Aug.16 [cited 2021Oct.24];24(2):42-8. Available from: https://he01.tci-thaijo.org/index.php/KDJ/article/view/241435
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