## 1 Introduction  
With recent technological breakthroughs, computer-assisted three-dimensional (3D) simulation has been widely applied to training courses for education in various medical fields. Three-dimensional simulation provides a virtual environment similar to the clinical setting [1]. The current literature reports that the effect of computer simulation on knowledge acquisition is equal or superior to that of traditional teaching methods [2], as evidenced by improvements in the critical thinking and spatial perception of students and clinical correlations. Today, methods for computer-based 3D simulation have been extended to dental education, specifically in training courses for diagnosis in periodonontology and orthodontics, caries removal, tooth preparation, and extraction [3, 4].  
Understanding the guidance of mandibular movement is essential for the accurate diagnosis of occlusal diseases and treatment for prosthetic rehabilitation [5]. The movement of the mandible is mainly related to two anatomic structures, namely, the teeth and temporomandibularibular joints [6]. The contact surfaces between the maxillary and mandibular anterior teeth determine anterior guidance, whereas the shape of the articular eminence of the temporal bone influences posterior guidance. Vertical and horizontal overlap of the anterior teeth is required to disengage the posterior teeth during excursive movements of the mandible and prevent harmful lateral forces on the posterior teeth. The specific trace and orientation of the mandible are set via the interaction between the teeth, joint structure, and neuromuscular system. Knowledge of related anatomic structures and understanding of the controlling factors in anterior and posterior guidance are important because the functional movement of the mandible influences chewing efficiency, phonetics and esthetics.  
Student learning outcomes are directly dependent on the relationship between the nature of the knowledge to be conveyed and the educational method used [7]. Interpretation of the complex spatial relationships and kinetics of mandibular movement can be challenging [8]. Illustrating the complex movement of the mandible and the dynamic nature of dental occlusion is difficult when using conventional teaching methods such as textbooks and two-dimensional images. Such crucial, yet complicated, knowledge is made more understandable through the use of 3D graphic visualization and simulation [9]. Previous research [10] on learner responses and learning effects related to the principles of occlusal adjustment compared the use of paper-based 2D presentations and computer-based 3D simulation methods, and concluded that 3D computer imaging helps learners acquire the required knowledge of occlusal adjustment.  
The purpose of this study was to assess the effects of computer-assisted 3D simulation on learning and self-assessment related to the guidance of mandibular movement. To conduct the evaluation, three teaching protocols, namely, lecture (L), lecture-to-simulation (Lts), and lecture with simulation (LwS), were compared with regard to actual and student-expected learning outcomes. The null hypothesis is that integrating computer-aided simulation into the teaching protocol on dental occlusion does not influence learning outcomes.