This work emphasises a cognitive approach to build ODONTOS, a computer-based education system in dentistry. It aims at providing for both instructors and students without any particular knowledge in computer programming; a tool dedicated to dental disease learning. For instructors, it implements for knowledge construction e.g. creating and proposing clinical cases according to student learning style, using multimedia technology.

For students it is a tool, which privileges their learning style in order to solve uniform and inflexible learning problem. World Wide Web (WWW) technology has allowed us to offer flexible learning program without any pressure of time and place to student.

13 instructors and 84 students tested the ODONTOS prototype via Internet and answered to the questions related to their habit regarding learning style for the students and knowledge construction for the instructors.

Although video data have emerged as an important learning support for the students (82 out of 84), their use in knowledge construction still remains unusual comparative with the use of text and picture (10 out of 13 instructors).

It appears that, the integration of video data should be more used by instructors (2 out of 13) while textual data are overwhelmingly used in knowledge construction (13 out of 13).

We introduce ODONTOS, and discuss the concrete contributions of this work.