Learning is an interactive process between the learner and thesurrounding structures, the so-called learning environment. Several typesof instructional interaction - such as the learner-tutor, the learner-learner, the learner-content, and recently, the learner-interface interactions - have been identified in higher education. The design execution of these interactions may significantly influence the learning impact of an academic educational session. Information and communication technology (ICT), and especially the Internet, has affected learning in many ways, but most significantly through introducing new possibilities for instructional interaction. The overriding aim of this thesis has been to elucidate the relative role of certain types of interaction between the learner and his or her environment in academic oral health education. In this thesis, ICT is studied in two distinct roles: as a mediator of communication?that is, as the mediator in learner-instructor and learner-learner interaction?and as a partner in interaction through the educational interface?the so-called learner-interface interaction (human?computer interaction). ICT as a mediator of communication was studied during two Internet-based problem-based learning (PBL) courses and one Internet-based examination of undergraduate students. The potential of ICT as a partner in interaction through the educational interface was investigated through an interactive software application, which aimed to improve the self-assessment ability of students. The results of these studies suggest that computer-mediated interaction (CMI) has an important role to play in higher education, can facilitate complex instructional methodologies such as PBL, and can effectively supplement and enhance face-to-face instruction. However, CMI presented several methodological differences when compared with face-to-face interaction, in terms of both quality as well as quantity of interaction. CMI was received less positively than face-to-face interaction by the students, when used in examination settings. In addition, it remains unclear if computer applications are able to constitute an effective, short-term, remedial support for the improvement of complex cognitive skills in students?such as self-assessment skills?without human feedback. At the basis of these findings and currently available technology, the most beneficial scenario from an educational point of view would include both computer-mediated and face-to-face interaction, with a considerable degree of user-determined flexibility. Future studies should focus on the roles of the various factors that affect learning through the process of interaction.

Problem Based Learning (PBL) has been fully or partly adopted by several medical and dental schools throughout the world, but only few attempts have been made to adjust this method to Distance Learning (DL) environments. It appears that the interaction demands of PBL could not be easily facilitated by the technologies used for DL in the past. The recent introduction of Virtual Learning Environments or Virtual Classrooms, is suggested by many as the development that could allow Distance Learning to utilise highly structured collaborative learning methods such as PBL. A literature review and two pilot studies were undertaken, in an attempt to investigate the possibility of adjusting an existing in-classroom PBL model to Internet-based environments for distance learning. There is a strong need of a conceptual theoretical framework and research results to support the function and effectiveness of distance learning in health education. Drop-out rates are still high in all kinds of distance education. Accreditation, team-work and personal contact, appear to be factors of importance for increasing motivation and minimising drop-out rates in distance learning. During the pilot studies it was evident that both postgraduate and undergraduate students were very positive towards the PBL method, as they experienced it while working over the network. However, it is very difficult to introduce inexperienced students to PBL through distance. Students? competence with computers seems to be an important factor for the success of a virtual classroom and their computer literacy has to be objectively assessed prior to any course. Significant differences were identified between in-classroom and over the Internet communication. These differences, although measured in the quantity of interaction, appear to influence the quality and depth of discussion as well. Tutor involvement was higher in the Internet discussions than the in-classroom ones. It was concluded that an entirely Internet-based PBL course is possible, if properly organised. However, such a model might constitute a compromise over the quality standards of in-classroom PBL, at least with the currently available Internet technology. A hybrid approach, which will combine personal contact with network-based interaction, might be the safest and most beneficial option right now.