## 4 Discussion
Given the diversity of studies in the literature, the need to standardize intraoral scanning methods is highlighted since each operating system determines a scanning method and sequence. Although the technique is well-established for obtaining single and partial implant-supported prostheses [33], the challenges are more significant in edentulous arches and may require the use of guides and additional devices to reproduce the distance between implants faithfully [3, 6, 20]. In other aspects, it is crucial to recognize advances in digital smile planning (Smile Design), as well as facial scanning. This control is evident in the improved planning of oral rehabilitation in terms of aesthetics and enhanced communication between professionals and patients. Patients also play a crucial role in this process, as they emphasize the relevance of previewing a treatment for analyzing the proposed treatment [20]. This ability to preview their treatment reassures them. Notably, facial scanning of the patient is a key aspect, providing information about the patient's face in 3D. This has been highlighted as a differential for analysis by both the professional and the patient [9]. The benefits of intraoral scanning extend beyond cases of edentulous patients. The literature has also emphasized the role of digital workflows in enhancing patient care, particularly in the use of conventional fixed and removable prostheses and maxillofacial prostheses [36, 37, 38]. Maxillofacial prostheses are described using the fully digital workflow [38]. However, challenges are reported in the literature regarding the costs of the fully digital workflow, especially in developing countries [9, 37]. Regarding the quality analysis of the articles, it is observed that there is a predominance of studies with longitudinal follow-up, with 4 prospective studies [3, 4, 9, 21] and 4 controlled and randomized clinical trials [6, 8, 20, 22], with a minimum follow-up period of 12 months and a maximum of 48 months. The main limitations raised during the bias analysis are related to the absence of sample calculation, deficiency in calculating the power of the test, and use of a convenience sample, in addition to studies that presented results with missing data, lack of standardization in the preparation of the results analyses, and difficulty in extrapolating the specificity and accuracy data found. The analysis of the certainty of the evidence also revealed a small sample in the studies evaluated and a lack of clear and consistent definitions of randomization and reinforces the need for longitudinal clinical follow-up studies in the area, especially with information on survival and complications of implant-supported prostheses, as well as clinical and laboratory execution time. Furthermore, several types of scan bodies are available on the market, and there are differences regarding the method of use, such as the need for additional calibration devices, such as palatal demarcation spheres or even splinting of the scan bodies. In this context, the heterogeneity of the studies allows us to establish, with reservations, the indication for all clinical cases, which underlies meticulous planning for the execution of the treatment and the need for more controlled and randomized clinical studies on the subject.