Clinical Evaluation of the Effect of the Scanning Pattern on Complete-arch Implant Scans

INTRODUCTION AND BACKGROUND Record-taking is a fundamental process and the starting point for manufacturing a dental prosthesis. The appearance of intraoral scanners (IntraOral Scanners (IOS)) has meant a revolution in this regard due to the advantages they provide, including better communication with both the patient and the dental laboratory, better comfort and acceptance by the patient, the immediacy in sending the file and saving space in the storage of digital models versus conventional ones. However, they are not exempt from problems, including their high cost, the learning curve, and difficulty achieving a reliable record in certain circumstances, including edentulous full-arch records.

Recordings of the edentulous full arch with IOSs pose a challenge due to the type of operation of these devices, which gradually collect and overlap information from small areas until completing a full arch. For this reason, different techniques have been proposed to improve the accuracy of this type of recording. In addition, if there is a case in which accuracy is crucial, it is complete edentulous arches with implants since, if the registration is not exact, the prosthesis manufactured on it will not have a passive fit in the mouth, which would lead to the appearance of both biological and mechanical complications.

Different studies have tried to analyze how various factors influence this accuracy, and these factors can be divided into factors related to the operator, the scanner, environmental conditions, or intraoral conditions-also different scanning strategies or heights and positions of the scan bodies. However, most of these works have been developed in an in vitro environment. This fact is motivated by the greater ease of making the records and, as a more relevant fact, the possibility of obtaining a reliable reference model, employing a coordinate machine (Coordinate Measurement Machine (CMM)) or a desktop scanner, something that in an in vivo study it is not possible.

The present study aims to clinically analyze the accuracy of different intraoral scanning strategies and types of scan bodies in edentulous full arch registrations on implants.

JUSTIFICATION Due to the importance of the accuracy in taking digital impressions in full-arch patients for the fabrication of restorations on implants, it is considered justified to study the influence of different scanning strategies and scan bodies on the accuracy of full-arch recording.