Influence of Operator Experience and Tooth Type on the Accuracy of Intraoral Scanning for Post and Core Restorations: An In Vitro Study

Description :

The study will compare scan accuracy between 3 groups: operator with less than 1 year of experience (low experience), operator with 1 to 3 years of experience (medium experience), and operator with more than 3 years of experience (high experience), resulting in 108 scans total (12 per group). To conduct the study, three extracted teeth (a central incisor, a premolar, and a molar) will be cleaned, disinfected, and prepared for post and core restorations with a standardized post-space depth of 10 mm. These teeth will be embedded in a typodont then placed on a dental manikin to replicate clinical conditions. A micro CT will be used to generate reference Standard Tessellation Language (STL) files for each tooth, which will serve as the refernce for comparison. Each operator will scan all three types of teeth 12 times, following a standardized protocol to ensure consistency, resulting in a total of 108 scans (36 per group). The same scanner model (Primescan) will be used, and calibration will be performed before each session. The obtained scans will be analyzed using software such as Geomagic Control X. The process will include manual alignment based on anatomical features, followed by fine alignment using the Iterative Closest Point (ICP) algorithm (1). Accuracy will be assessed through Hausdorff distance analysis, evaluating trueness (mean deviation) and precision (standard deviation across repeated scans). Statistical analysis will be performed to determine if significant differences exist between the two groups.

Titulaire :
HABRE HALLAGE Pascale

Contact USJ :
pascale.habrehallage@usj.edu.lb

Chercheur(s) :
Dr Pascale HABRE HALLAGE

Projet présenté au CR, le : 01/05/2025

Projet achevé auprès du CR : 01/06/2026