1995 Volume 39 Issue 1 Pages 58-66
Tooth carving practice is the most fundamental training for students of dental technician training schools to learn the morphology of teeth.
Various tooth carving techniques have been advocated, but students should be trained in techniques that are easy to understand, simple, and less likely to cause accidental cut injuries.
In this study, after guidance manuals of the design mode technique our school adopted (A), Obana's dessin mode technique (B), and direct carving method (C) were explained and demonstrated to students, 10 consecutive tooth carving tasks were assigned. By evaluating the skill acquired by the students from the overall viewpoint and dimensional errors in comparison with the standard model, the following results were obtained.
1. The variance of regression between the number of repetitions of tooth carving assignment and the evaluation point of the product was highly significant in all 3 techniques. The gradient of the regression curve was 0.19, 0.13, and 0.08 in the techniques A, B, and C, respectively, being greatest in technique A.
2. The variance of regression between the number of repetitions of tooth carving assignment and the absolute value of the dimensional errors of the product was significant in technique A, highly significant in technique B, but was not significant at the 5% level in technique C. The gradient of the regression curve was similar for techniques A and B, being -0.032 and -0.034, respectively.
3. Dimensional errors at various sites showed a nearly normal distribution in all techniques at the first assignment.
4. The variance of regression between the number of repetitions of tooth carving assignment and the rate of dimensional errors, which were within ±10% of the standard dimensions, was highly significant in techniques A and B but was not significant at the 5% level in technique C. The gradient of the regression curve was 2.19 in techniques A and 2.51 in technique B, being slightly greater in the latter.
