J Korean Acad Prosthodont.  2021 Jul;59(3):261-270. 10.4047/jkap.2021.59.3.261.

Reverse engineering technique on the evaluation of impression accuracy in angulated implants

• Jung HT
• Lee KS
• Song SY
• Park JH
• Lee JY

• KMID: 2518725
• DOI: http://doi.org/10.4047/jkap.2021.59.3.261

Abstract

Purpose
The aim of this study was (1) to compare the reverse engineering technique with other existing measurement methods and (2) to analyze the effect of implant angulations and impression coping types on implant impression accuracy with reverse engineering technique.
Materials and methods
Three different master models were fabricated and the distance between the two implant center points in parallel master model was measured with different three methods; digital caliper measurement (Group DC), optical measuring (Group OM), and reverse engineering technique (Group RE). The 90 experimental models were fabricated with three types of impression copings for the three different implant angulation and the angular and distance error rate were calculated. One-way ANOVA was used for comparison among the evaluation methods (P < .05). The error rates of experimental groups were analyzed by two-way ANOVA (P < .05).
Results
While there was significant difference between Group DC and RE (P < .05), Group OM had no significant difference compared with other groups (P > .05). The standard deviations in reverse engineering were much lower than those of digital caliper and optical measurement. Hybrid groups had no significant difference from the pick-up groups in distance error rates (P > .05).
Conclusion
The reverse engineering technique demonstrated its potential as an evaluation technique of 3D accuracy of impression techniques.

Keyword

Digital evaluation method; Hybrid impression coping; Implant angulation; Reverse engineering technique