Análisis de la efectividad de un sistema auxiliar de anillas diseñadas para modificar la geometría de scanbodies durante el procedimiento de captación óptica intraoral : estudio in vitro

Abstract

Background: Intraoral scanners (IOSs) provide virtual models that enable a digital workflow for dental prosthetic design and/or fabrication. Intraoral optical acquisition of intraoral scanbodies (ISBs) allows relative orientation of each implant position in the virtualmodel on which the prosthesis is designed. Currently, fully intraorally scanning of edentulous arches with geometrically identical or similar ISBs is considered a controversial indication. Thus, this method is not the recommended in these cases due to the poor predictability of the optical behavior of the IOSs, as well as the inconsistency of the reported results regarding the accuracy of the resulting models. Numerous devices, tecniques, and auxiliary resources have been developed with the aim of optimizing the optical behavior of IOSs, as well as the accuracy of the resulting models in terms of efficiency and efficacy. Completely edentulous arches, present anatomical patterns that could imply unfavorable optical scanning conditions, especially in the mandible. These conditions become even more pronounced when scanning flat ridges or mobile surrounding tissues. Furthermore, the presence of repetitive on-surface patterns, such as geometrically similar ISBs, increase the risk of introducing scanning errors due to overlapping. These optical problems arise due to stitching inconsistencies when considering mismatched references between sequential scan frames. Optical acquisition errors not just have a negative impact on scanning efficiency, but also may also introduce inaccuracies in the models generated during the reconstruction process. Alternative or complementary techniques to intraoral scanning with IOS, such as those based on photogrammetry, or 3D radiology, may help to overcome some of the limitations. However, their use is not always justified, as the involve other disadvantages, such as exposure of the patients to ionizing radiation and/or a significant implementation cost. Therefore, this PhD research is justified with the objective to assess the efectiveness of an auxiliary system designed for geometric modification of identical ISBs, which aims to improve intraoral scanning effectiveness, as well as the accuracy of the resulting models in terms of efficiency. .Objectives: The aimof the present reserch is to evaluate the effectiveness of intraoral scanning with identical multiple scan bodies (ISBs) using customized over scan body rings (COR) as an auxiliary system.