## 4 Discussion
This comparative analysis made use of a digital intraoral scanner and two specific software packages, which, through the application of best fit algorithms, offer comprehensive, rapid, data analysis. The study protocol enabled the measurements offered by the models to be reproduced and provided a reliable and objective evaluation of the results, thereby reducing errors originating in the operator. Digital technologies are common in dentistry, yet they are subject to certain limitations in comparison with conventional techniques, such as the difficulty in detecting subgingival termination lines, the difficulty in registering the gingival emergence in deep implants, or the complexity of rehabilitating a full arch, despite good precision for small prostheses. These methods also require changes in work protocols, requiring a learning curve and familiarization with the techniques involved; the use of intraoral scanners to obtain a digital impression necessarily calls for experienced professionals. Furthermore, there is the need for a considerable economic outlay for the introduction of such equipment in a clinical setting [22, 23, 24, 25, 26]. Moreover, BOPT is a new technique in the scientific literature, and there is a need to evaluate the behaviours of soft tissues in publications with long-term follow-up prospective studies. In the literature, we found no article that follows an objective methodology like ours. Thus, it was impossible to make a comparison with our study. We consider that alignment process to be highly significant, i.e., the alignment of files with respect to the global coordinate system carried out in Phase 2. Although we believe this is a tedious and complex process, it is of paramount importance when it comes to measuring changes since the operator does not intervene at the moment of selecting points 3B, 3L, 4B, and 4L; instead, these points are obtained through mathematical formulations based on the previous alignment. Hence, examiner's errors were eliminated in the determination of these points, while the possible errors of alignment with respect to the global coordinate system still have the same influence over all the points. The data obtained in the study support the hypothesis presented at the beginning of the article. Among our findings, we found that at the buccal level, a change in thickness is a better predictor  
Figure 20: Situation after treatment with BOPT (Lateral view). of a change in height compared to the results at the lingual level. In the buccal zone, we found a moderately strong correlation (r = 0.636), while in the lingual zone, the correlation was slightly weak (r = 0.379), despite also being significant (\(p\) = 0.042). The clinical implications, considering the results obtained in this study, allowed us to objectively demonstrate that if we want to displace the zenith of a tooth towards the mesial or distal direction, or if we wish to reshape a certain gum or gingival margin towards the apical or coronal direction, we have to modify the angle of the emergence profile of the prosthesis. Therefore, if we have an anterior tooth and wish to simulate the zenith towards the distal direction with a crown, we would have to increase the emergence of the crown in distal by more than 60\({}^{\circ}\) to a maximum of 90\({}^{\circ}\); in mesial, we would create an angulation that is less than 30\({}^{\circ}\); therefore, the gum in the mesial direction would move down and thin out, while in distal, it would become displaced towards the apical direction and thicken. In cases of a recession where we need the gum to move down after BOPT (with the proviso that the bone scalloping remains healthy), we would treat the patient under BOPT and reduce the emergence of the prosthetic cervical angle, giving it an angulation of less than 45\({}^{\circ}\), thereby allowing the gum to migrate coronally. Thin gingiva is associated with a greater influence of recessions in orthodontic treatment [27]. There are also limitations to this study.