Comparison of intraoral scan precision according to surface roughness of the prepared abutment models
10.4047/jkap.2026.64.1.15
- Author:
Dong-Joon SONG
1
;
Hee-Jung KIM
;
Joo-Hun SONG
Author Information
1. Department of Prosthodontics, School of Dentistry, Chosun University, Gwangju, Republic of Korea
- Publication Type:ORIGINAL ARTICLE
- From:The Journal of Korean Academy of Prosthodontics
2026;64(1):15-26
- CountryRepublic of Korea
- Language:English
-
Abstract:
Purpose:The purpose of this study was to determine scanning accuracy (precision) of an intraoral scanner according to surface roughness of the prepared abutment models and to identify the most advantageous tooth surface roughness for scanning.
Materials and methods:Using Computer-Aided Design (CAD) software (Autodesk Meshmixer), four maxillary molar abutment models were designed to fit the maxillary dentiform and printed with Polymethylmethacrylate (PMMA) (MAZIC D temp) using a 3D printer (Carima IMD). The teeth were fixed to the dentiform. Each model was prepared with four diamond burs of different grit sizes:Coarse (125 – 150 µm), Medium (106 – 125 µm), Fine (53 – 63 µm), and Extra-fine (20 – 30 µm), producing four abutment groups (group G, B, R, Y). Each model was scanned twice with an intraoral scanner (Primescan), generating paired scan files that were overlapped and aligned. This was repeated ten times, yielding 20 files (10 pairs) per model. The precision of the 10 pairs was evaluated with 3D analysis software (GOM Inspect 2018). A point guide created with Autodesk Meshmixer was used to analyze deviations at 14 fixed points. The analysis was conducted from three perspectives: First, whether precision differed as surface roughness changed; second, whether there was a difference in precision between the seven upper and seven lower points in each model; third, whether the presence and direction of adjacent teeth influenced precision, assessed by deviations at mesial, distal, buccal, and palatal points. Differences in mean deviations among the groups and the directions were statistically analyzed using ANOVA (α = 0.05), and the differences between the upper and lower points were analyzed using an independent samples T-test (α = 0.05).
Results:Deviations according to abutment surface roughness were lowest in group Y, followed by R, B, and G (P < .05). No statistical significance was observed between the seven upper and seven lower points in groups G, B, R, and Y (P > .05). To determine differences in scan precision by directions, points on the same horizontal plane were grouped, and mean deviations among the seven groups were compared. No statistical significance was found (P> .05).
Conclusion:When preparing an abutment for prosthesis restoration, the consistency and precision of intraoral scan improve as the surface roughness decreases and angled areas are finished smoothly. In addition, if a skilled operator performs the intraoral scan consistently, there is no significant difference in scan precision according to the location of the scanned point.
