Evaluation of Three-Dimensional Digital Models Formulated From Direct Intra-oral Scanning of Dental Arches in Comparison With Extra-oral Scanning of Poured Dental Models in Terms of Dimensional Accuracy and Reliability

Samer T Jaber; Mohammad Y Hajeer; Khaled Walid Alkhouli; Rabab Mohamad Al-Shamak; Khaldoun M A Darwich; Ossama Aljabban; Mohammad Khursheed Alam; Jehad M Kara-Boulad

doi:10.7759/cureus.54869

Evaluation of Three-Dimensional Digital Models Formulated From Direct Intra-oral Scanning of Dental Arches in Comparison With Extra-oral Scanning of Poured Dental Models in Terms of Dimensional Accuracy and Reliability

Cureus. 2024 Feb 25;16(2):e54869. doi: 10.7759/cureus.54869. eCollection 2024 Feb.

Authors

Samer T Jaber¹, Mohammad Y Hajeer², Khaled Walid Alkhouli³, Rabab Mohamad Al-Shamak³, Khaldoun M A Darwich⁴, Ossama Aljabban², Mohammad Khursheed Alam⁵, Jehad M Kara-Boulad⁶

Affiliations

¹ Department of Orthodontics, Faculty of Dentistry, Al-Watanyia Private University, Hama, SYR.
² Department of Orthodontics, Faculty of Dentistry, University of Damascus, Damascus, SYR.
³ Department of Orthodontics, Faculty of Dentistry, Syrian Private University, Damascus, SYR.
⁴ Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Damascus, Damascus, SYR.
⁵ Department of Preventive Dental Science, College of Dentistry, Jouf University, Sakaka, SAU.
⁶ Department of Orthodontics, Faculty of Dentistry, Al-Hawash Private University, Homs, SYR.

Abstract

Background: The study's objective was to assess the dimensional accuracy and reliability of dental digital models prepared by direct intraoral scanning and indirect scanning of the plaster models compared to the plaster models as the gold standard.

Materials and methods: This study included 20 patients. Nine had a class I malocclusion, seven had a class II malocclusion, and four had a class III malocclusion. Intraoral scanning was done for the upper and lower arches of all the patients enrolled in this study using an intraoral scanner (i700; Medit, Seoul, Korea). The next step was preparing the plaster model for the control group. Addition-silicone impressions were taken for each patient's arches. The impressions were poured according to American Board of Orthodontics (ABO) standards. Finally, the digital models of the indirect scanning group were prepared using a 3D desktop scanner (T710; Medit). In total, 26 measurements were made on the plaster and digital models. Paired t-tests were used to test for significant differences between the studied groups. The reliability of the studied techniques was tested using intraclass correlation coefficients (ICCs). Because of the multiple comparisons, the ɑ level was adjusted and set at 0.002.

Results: No significant differences were found between the intraoral scanning group (20 patients) and the plaster models group (20 patients; P>0.002). The ICCs ranged from 0.814 to 0.993, indicating excellent agreement between the direct digital and traditional plaster models. There were no significant differences between the digital and original plaster models (P>0.002). ICCs ranged from 0.834 to 0.995, indicating excellent agreement between the indirect digital and original plaster models. No significant differences were detected between the direct and indirect digital models (P>0.002). ICCs ranged between 0.813 and 0.999, indicating excellent agreement between direct and indirect digital models.

Conclusion: Both direct and indirect scanning techniques are accurate and reliable for digital model preparation and can be considered an alternative to traditional plaster models used in clinical orthodontics diagnostic applications. The intraoral scanning technique can be considered a valid alternative for indirect scanning of the plaster models to prepare digital working models during the digital design and fabrication of orthodontic appliances such as clear aligners.

Keywords: accuracy; desktop scanner; digital models; intraoral scanner; model analysis; orthodontic; orthodontic models; precision; reliability; validation.