Accuracy of IOS in Full-Arch Dentate Patients Compared to CBCT Cast-Scanning. An In-Vivo Study

Abstract

Twenty fully-dentate patients were enrolled in the study.Full-arch maxillary and mandibular PVS impressions were acquired using stock metal trays and the dual mix technique. A full-arch maxillary and mandibular intraoral scanner (IOS) was also obtained using the Trios IOS. The impressions were cast and subsequently scanned using a Planmeca Promax cone beam computed tomography (CBCT) scanner. The casts were also scanned in a Desktop Scanner for reference(7series Dental Wings). DICOM files from the CBCT device were converted into stl files. The.stl files from the CBCT and IOS devices were compared for accuracy against the reference files from the Desktop Scanner using a 3D surface measurement software. Statistical analysis was carried out using SPSS software. Trios had a smaller error (median = 39μm) than CBCT (median = 62μm),a statistically significant difference between the 2 modalities (z=-4.6, p⟨0.005).Concerning the IOS, the anterior teeth presented with a smaller error (42±16μm) as opposed to the posterior teeth (47±16μm), a significant difference (t(39)=-2.4, p=0,019). There were no significant differences in IOS mean accuracy between maxilla and mandible or between left and right quadrants. Fullarch digitization using the Trios IOS is significantly more accurate compared to CBCT scanning of the relevant plaster models. Anterior teeth Trios IOS is statistically more accurate compared to posterior teeth IOS.

Keywords: CBCT Scanning; Full-Arch Accuracy; Intraoral Scanning.