Case report: Fabrication of a dental implant guide based on tetrahedron positioning technology.

BACKGROUND: Conventional static computer-assisted implant surgery (s-CAIS) requires special equipment, such as 3D printers or computer numerical control (CNC) lathes. We present a low-cost workflow for manufacturing dental implant guides based on tetrahedron positioning technology (TPT). The aim of this case report was to use a surgical guide technique for dental implant placement using tetrahedron positioning technology. CASE PRESENTATION: A 28-year-old man consulted for the treatment of a missing right first mandibular molar by implant placement. The cone-beam computed tomography (CBCT) data were imported into medical image processing software for analysis, and the implant design was simulated. The implant design on CBCT was transferred to the mandibular model using TPT, and the implant surgical guide was made to guide the dental implant operation. CBCT was performed postoperatively and compared with the preoperative design to check the accuracy. The central deviation of the implant head was 0.31 mm, the central deviation of the implant apex was 0.93 mm, and the implant angular deviation was 2.45°. CONCLUSION: The use of tetrahedral positioning technology based on CBCT data is a new method for making implant guides. It is a promising technique offering a highly predictable outcome and lower risk of iatrogenic damage. However, these results should be interpreted with care since they are based on limited evidence from a case report. Larger population studies with longer follow-up periods and standardized experimental studies are required.

Fabrication of guide and removal of fiber post by tetrahedron positioning technology at the chair side: a case report and literature review / 口腔疾病防治

Objective @#To explore the technology and efficacy of fabrication of a guide and removal of a fiber post by tetrahedron positioning technology at the chair side.@*Methods@# For one patient with acute chronic periapical periodontitis of the left maxillary lateral incisor who needed to have the fiber post removed, the chair side tetrahedral positioning technique was used to make a guide plate to remove the fiber post. Cone beam CT (CBCT) data were imported into the software to design the guide plate for fiber post removal. The guide plate design on CBCT was transferred to a solid model by using tetrahedral positioning technology. The guide plate was made to guide the removal of the fiber post, and then left maxillary lateral incisor root canal was performed. We evaluated the effect of fiber post removal with tetrahedral positioning technology by reviewing the literature.@*Results @#The guide plate made by tetrahedral positioning technology can accurately locate the position and direction of fiber posts at a low cost and with high speed. After the fiber post was removed, the root canal could be dredged by using root canal preparation instruments. After root canal preparation, the root canal was filled with warm gutta-percha to complete the root canal treatment. After 3 months, the apical radiograph showed that the transmission shadow of the apical area was reduced. The results of the literature review showed that the fiber post removal with guide plates provides a predictable result and a lower risk of iatrogenic damage. Minimally invasive treatment can be carried out, and chair time can be reduced.@*Conclusion@#On the basis of CBCT data, using tetrahedral positioning technology to make fiber post removal guides can help reduce the risk of fiber post removal and has the characteristics of speed, low cost and short chair side processing. However, the accuracy comparison between tetrahedral positioning technology and 3D printing guides needs further study.