Accuracy of a workflow using sleeveless 3D printed surgical guides made from a cost‐effective and biodegradable material: An in vitro study

Abstract

Background : Digital implant planning and guided insertion facilitates prosthetically-driven implant positioning. Nowadays, most guide systems are using photopolymerized 3D printed surgical templates with metal sleeves for drill guidance. However, a cost-effective but accurate alternative might be represented by sleeveless surgical guides made of polylactate. Since absence of wear cannot be secured using sleeveless surgical guides, this biodegradable material could be beneficial.Aim/Hypothesis : To determine the accuracy of the implant position installed with surgical guides obtained by Fused Deposition Modeling (FDM) or Stereolithography (SLA). Moreover, a potential benefit of inserted metal sleeves and the influence of the implantation site was evaluated.Material and Methods : A surgical guide for the insertion of two titanium implants in a lower jaw resin model in the region of the second premolar and molar was virtually designed with (S) and without (NS) metal sleeves. Each dataset was 3D printed ( n = 10) using SLA and FDM technologies, resulting in four groups (SLA-S, SLA-NS, FDM-S, FDM-NS). Finally, a total of 80 two-piece titanium implants were inserted in the resin model. Scan bodies were used for the digitization by means of a desktop scanner. Discrepancies between the final and virtually planned implant position were measured using an inspection software. Horizontal and vertical deviations at apex and shoulder level, as well as main axis deviations were calculated. For the statistical analysis one-way ANOVA with post-hoc Tukey tests was used.Results : Inserted implants showed maximum horizontal deviation values of 0.97 mm at the implant tip and 0.55 mm at the implant shoulder.(Fig. 1) Furthermore, maximum deviations in the vertical dimension of 0.56 mm at the implant tip and 0.24 mm at the implant shoulder were measured. The implants maximum deviation to the main axis was 3.02°. When comparing the four evaluated groups (SLA-S, SLA-NS, FDM-S, FDM-NS), no statistically significant differences regarding to the implant site were found ( P > 0.05). Likewise, insertion of a metal sleeve had no significant impact on accuracy ( P > 0.05). Pairwise comparisons regarding the manufacturing technology (SLA FDM) showed significant differences between FDM-S and SLA-S ( P = 0.023) for the lateral deviations at apex. Conclusion and Clinical Implications: Within the limitations of the present laboratory setup, all installed implants showed a maximal deviation <1 mm and might be therefore considered suitable for clinical use. Both evaluated 3D printing technologies showed similar outcomes irrespective of the region in the jaw model and the use of metal sleeves does not improve the accuracy of the implantation procedure.

Accuracy of two 3D printing technologies in manufacturing of dental implant surgical guides (An in vitro study)

“…These results are in agreement with Pieralli et al2020 [18] which concluded that Comparable levels of accuracy in implant placement were achieved when utilizing FDM and SLA printed surgical guides This coincides with Hromadnik et al 2020 [19] which reported that when comparing the four evaluated groups (SLA-S, SLA-NS, FDM-S, FDM-NS), no statistically significant differences regarding to the implant site were found.…”

In Vitro Comparison between Metal Sleeve-Free and Metal Sleeve-Incorporated 3D-Printed Computer-Assisted Implant Surgical Guides

“…Studies that compared the accuracy of implant placement in relation to the pre-planned implant positions with the use of surgical guides commonly used surgical guides that required metal sleeve insertion; industrial 3D printers were used to fabricate the body of the surgical guides, and the metal sleeves were inserted [ 12 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. As in-office 3D printers are becoming more popular and their accuracy is being reported as comparable to that of industrial printers, metal sleeveless surgical guides are becoming a major trend [ 23 , 24 , 25 ].…”

3-D Printed Protective Equipment during COVID-19 Pandemic

“…Visors can be manufactured from several types of materials that include polycarbonate, propionate, acetate, poly(vinylchloride), and PETG [9]. Since PLA and PETG are known to show volume change during sterilization processes [21], one-time use of the visor is recommended, whereas a study showed that sterilized 3-D printed surgical splints using filaments based on lignin (Green-TEC Pro) remained dimensionally stable [22]. The sterilization of the frame might be possible, but was not tested in this study.…”