## 4 Virtual Reality in Maxillo-Facial Surgery  
Advancements in simulation-based education allowed learners to practice and opened opportunities for professionals to plan a wide array of surgical procedures. Its applications vary from evaluating accuracy for orthognathic surgery [42], obtaining a perfect match of virtual planes for jaw reconstruction [43], to correct placement of dental implants by guiding its direction and proximity with other important structures [44]. Virtual planning of implants has revolutionized implant dentistry as it has the potential for treating complex cases in immunocompromised patients with least invasive surgical procedure. Dynamic navigation or static guide approaches are utilized to transfer 3D virtual planning onto the surgical field [45]. Dynamic navigation has an advantage over the latter technique as it aids in adjusting the implant's direction in a flexible manner using virtual planning. Established on the virtual designing, static transfer of plan involves fabrication of surgical guide followed by the use of CAD/CAM for implant insertion. In accordance with the type of support (such as dental, mucosal, or bony support), numerous types of surgical guides are accessible to obtain an exceptional accuracy [46]. Formerly, accessibility of computer programs enabled its users to determine the position of dental implant [47; 48] but these programs lacked the potential to give the bone drilling feel to its users [49]. However, initiation of virtual reality simulation (VRS) in the training programs offered opportunities and enabled its users to have a perception of touch along with sight [50]. The system proved to be beneficial for evaluating intimate details of the procedures performed and therefore imparts a rigorous assessment [51]. The haptic devices used in the VRS allows its users to detect the texture of the surrounding soft tissues or bone handling drill, consequently preparing them for real case scenarios [52]. Similarly, orthognathic surgery involving the use of navigation in a virtual environment gave remarkable accuracy in patients. Preoperative simulations comprising of navigation system were utilized to perform the surgeries which included fractures, TMJ ankylosis, cleft lip repair [53], fibrous dysplasia, mandibular hypertrophy, and tumors [54; 55]. Literature mentions the significance of virtual reality simulation for the standardization of dental education and need of more studies to optimize the value, assessment method, student feedback, and mechanism of integration in dental curriculum. Numerous methods have been proposed to motivate students towards self-learning thus reducing the faculty time and ameliorating their training skills. Various simulators have been introduced including VOXEL-MAN(r) simulators, which enabled its users to self-assess themselves, validate their training, and represent a safe, realistic, non-destructive, easily accessible surgical anatomy for junior's resident. It is also low cost. Along with their skill refinement, the majority emphasized the training of technical skills. However, there exists a gap in these simulator models in terms of non-technical skills, thus creating problems for its users while working in stressful environments such as operation theatres. In Table 4, discussion of the reported studies on the applications of VR-based simulators for the oral and maxillofacial surgery.