## 4 Discussion  
This narrative review depicts the potential application of VR, AR and MR, AI and Robotics in dentistry. The decision to provide a narrative review could be considered as a limitation of this study; however, it allows the provision of an accurate overview of the recent scientific literature on the potential use of VR, AR, MR, AI and Robotics in the dental field. The broad perspective might become lost using a systematic review, since it focuses on a specific query, as in PRISMA guidelines [78]. As reported in the scientific literature, a narrative review summarizes the literature in a way which is not explicitly systematic, but it is suited to addressing a topic in wider ways [10]. In the field of dental education, VR and AR can improve the teaching of dental morphology from both an economic and practical standpoint. The use of cadavers or synthetic recreations (silicone or plastic models) represents the current gold standard for studying head and neck anatomy in dental schools and postgraduate courses. AR and VR are reusable, unlike cadavers and synthetic recreations, making them more economically viable. They can also enhance visualization of anatomical structures, thereby improving understanding of dental structures. Furthermore, using these new technological approaches may promote students' motivation and interest in learning. The use of virtual simulators in professional education programs can allow students to refine their clinical skills without the risk of harming a patient during the learning process and, in this era of COVID-19, to certainly avoid potential infection [17]. Using VR, AR or MR simulators, a more realistic training could also support and reinforce ergonomics, thus improving the students' preclinical experience [79]. The type of simulation chosen by the dental student can range from simple cavity preparation to more complex overlay or crown preparation. The virtual simulator may give direct feedback to the student and therefore improve clinical skills in a faster and safer manner. Although VR, AR and MR may improve the dental education, more information about their learning theories are required [80]. [PERSON] et al. investigated the process of learning of immersive reality systems and highlighted the need to develop learning theories by using a research-based theoretical model so that personnel such as students, teachers, and instructional designers would possess the correct knowledge for adopting such devices [80]. Moreover, a recent review revealed that few design-oriented studies constructed their VR applications based on a specific learning theory, which serves as technical development guidance [81]. Apart from dental education, AR and VR may help to reshape clinical dentistry. Computer-generated information may be superimposed on the surgical field using AR and VR [82]. These technologies may reduce the time needed for consulting digital information, but more importantly, they allow the clinician to focus on the patient. The application of AR and VR in clinical practice may not only be useful for dental students and clinicians as previously discussed, but also for patients. AR and VR can present suitable specific non-invasive strategies to reduce dental anxiety and treat dental phobias, one of our society's phobic conditions [38]. AR and VR could represent useful aids to manage or even overcome dental phobias, such as by using videogames or even by the total immersion of the patient into a virtual environment. These technologies can be used to implement oral health education strategies. For example, teaching toothbrushing techniques could become more feasible, effective, and accessible to children by linking learning with fun [83]. Consequently, AR and VR based-games may also be customized to correct brushing techniques after identifying mistakes [84]. These innovative technologies can improve communication between dental practitioners, dental technicians, patients, and the multidisciplinary team.