Accuracy of a 3D printed sleeveless guide system used for fiber post removal: An in vitro study

Siyi Mo; Yongwei Xu; Lei Zhang; Ye Cao; Yongsheng Zhou; Xiaoxiang Xu

doi:10.1016/j.jdent.2022.104367

Accuracy of a 3D printed sleeveless guide system used for fiber post removal: An in vitro study

J Dent. 2023 Jan:128:104367. doi: 10.1016/j.jdent.2022.104367. Epub 2022 Nov 17.

Authors

Siyi Mo¹, Yongwei Xu², Lei Zhang¹, Ye Cao¹, Yongsheng Zhou¹, Xiaoxiang Xu³

Affiliations

¹ Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA key Laboratory for Dental Materials, Zhongguancun South Avenue 22, Beijing 100081, China.
² Department of dentistry, Peking University People's Hospital, Xizhimen South Street 11, Beijing 100044, China.
³ Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing Key Laboratory of Digital Stomatology, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, NMPA key Laboratory for Dental Materials, Zhongguancun South Avenue 22, Beijing 100081, China. Electronic address: xiaoxiang86@bjmu.edu.cn.

PMID: 36402258
DOI: 10.1016/j.jdent.2022.104367

Abstract

Objectives: The removal of fiber post is often a challenging task. A 3D printed assembled sleeveless system that guides the head of the handpiece instead of the drill was developed to address this issue. This study aimed to evaluate the accuracy of this novel guide system using an in vitro approach.

Methods: A standard maxillary typodont was digitized. The right first molar, the right central incisor, the left first premolar, and the left second molar in the digitized dentition were virtually crown-amputated. Four cylinders (diameter: 6 mm, height: 12 mm) were positioned along the directions of the main roots of these teeth to establish the virtual test model. Ten copies of the test model were printed using light-polymerizing resin. Four assembled sleeveless guide systems targeting the cylindrical axes were designed and printed using titanium alloy. One senior prosthodontist performed the drilling task targeting each cylindrical axis aided by the guide system or freehand (20 teeth each). The drilled models were scanned. The coordinates of the centers of all perforations and circular bases on the coronal and apical surfaces were obtained. The linear and angular deviations between the actual drilling path and the cylindrical axis for each tooth were calculated and analyzed.

Results: The guided group exhibited significantly smaller linear and angular deviations than the freehand group (coronal linear deviation: 0.19 ± 0.09 mm vs. 0.35 ± 0.18 mm, p = 0.0012; apical linear deviation: 0.54 ± 0.19 mm vs. 1.71 ± 0.51 mm, p < 0.001; angular deviation: 2.67 ± 1.07° vs. 8.48 ± 2.86°, p < 0.001).

Conclusion: The accuracy of the 3D printed assembled sleeveless guide system used for fiber post removal is superior to that of the freehand method within the limits of an in vitro design.

Clinical significance: For the removal of fiber posts, the present 3D printed sleeveless guide system can provide better accuracy that the conventional freehand method. This may justify the diffusion of the guided technique for fiber post removal.

Keywords: 3D printing; Computer-aided design; Dental root post; Guided technique; In vitro study.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bicuspid / surgery
Computer-Aided Design
Dental Implantation, Endosseous* / methods
Maxilla
Printing, Three-Dimensional
Research Design*