scholarly journals Accuracy of Implant Position Reproduction According to Exposed Length of the Scan Body during Optical Scanning: An In Vitro Study

2021 ◽  
Vol 11 (4) ◽  
pp. 1689
Author(s):  
Na-Eun Nam ◽  
Seung-Ho Shin ◽  
Jung-Hwa Lim ◽  
Bora Lee ◽  
June-Sung Shim ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Three Dimensions ◽  
Lateral Incisor ◽  
Implant Position ◽  
Optical Scanner ◽  
Implant Placement ◽  
Bone Level ◽  
Scan Data ◽  
Mean Square Errors

Accuracy of implant position reproduction according to various types of scanners, implant placement depths, and tooth positions are unknown. The purpose of this study was to compare the accuracy of implant position reproduction for differences in the exposed length of the implant scan body according to scanner type and tooth position. Implants were placed at the positions of the lateral incisor, first premolar, and first molar in the study model at the bone level and submerged 1.5 mm, 3.0 mm, 4.5 mm, and 6.0 mm. The completed models were scanned with one type of tabletop scanner and three types of intraoral scanners (TRIOS 3, i500, and CS3600). A matching process was performed for all scan data to superimpose abutment library data on the scan body, and the root mean square errors were analyzed in three dimensions to evaluate the position reproducibility of the replaced abutment library. In the trueness analysis, the error increased rapidly for an implant placement depth of 4.5 mm, and was largest for a submersion of 6.0 mm. The precision analysis confirmed that the error increased for depths of at least 3.0 mm. The analysis by position identified that the accuracy was lowest for an implant placed at the position of the lateral incisor. These findings indicate that special care is required when making an impression of a deep implant with an optical scanner.

scholarly journals Accuracy of Guided Implant Surgery in the Edentulous Jaw Using Desktop 3D-Printed Mucosal Supported Guides

2021 ◽  
Vol 10 (3) ◽  
pp. 391
Author(s):  
Rani D’haese ◽  
Tom Vrombaut ◽  
Geert Hommez ◽  
Hugo De Bruyn ◽  
Stefan Vandeweghe
Keyword(s):  
In Vitro Study ◽  
Angular Deviation ◽  
Implant Surgery ◽  
Implant Position ◽  
Surgical Guides ◽  
Negative Effect ◽  
Bone Level ◽  
3D Printed ◽  
Implant Alignment

Purpose: The aim of this in vitro study is to evaluate the accuracy of implant position using mucosal supported surgical guides, produced by a desktop 3D printer. Methods: Ninety implants (Bone Level Roxolid, 4.1 mm × 10 mm, Straumann, Villerat, Switzerland) were placed in fifteen mandibular casts (Bonemodels, Castellón de la Plana, Spain). A mucosa-supported guide was designed and printed for each of the fifteen casts. After placement of the implants, the location was assessed by scanning the cast and scan bodies with an intra-oral scanner (Primescan®, Dentsply Sirona, York, PA, USA). Two comparisons were performed: one with the mucosa as a reference, and one where only the implants were aligned. Angular, coronal and apical deviations were measured. Results: The mean implant angular deviation for tissue and implant alignment were 3.25° (SD 1.69°) and 2.39° (SD 1.42°) respectively, the coronal deviation 0.82 mm (SD 0.43 mm) and 0.45 mm (SD 0.31 mm) and the apical deviation 0.99 mm (SD 0.45 mm) and 0.71 mm (SD 0.43 mm). All three variables were significantly different between the tissue and implant alignment (p < 0.001). Conclusion: Based on the results of this study, we conclude that guided implant surgery using desktop 3D printed mucosa-supported guides has a clinically acceptable level of accuracy. The resilience of the mucosa has a negative effect on the guide stability and increases the deviation in implant position.

scholarly journals Effects of Groove Sealing of the Posterior Occlusal Surface and Offset of the Internal Surface on the Internal Fit and Accuracy of Implant Placements Using 3D-Printed Surgical Guides: An In Vitro Study

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1236
Author(s):  
Jung-Hwa Lim ◽  
Enkhjargal Bayarsaikhan ◽  
Seung-Ho Shin ◽  
Na-Eun Nam ◽  
June-Sung Shim ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Internal Surface ◽  
Three Dimensions ◽  
Surface Shape ◽  
Digital Data ◽  
Surgical Guide ◽  
Implant Placement ◽  
Surgical Guides ◽  
Internal Fit

This study evaluated the internal fit and the accuracy of the implant placement position in order to determine how the surface shape of the tooth and the offset influence the accuracy of the surgical guide. The acquired digital data were analyzed in three dimensions using 3D inspection software. The obtained results confirmed that the internal fit was better in the groove sealing (GS) group (164.45 ± 28.34 μm) than the original shape (OS) group (204.07 ± 44.60 μm) (p < 0.001), and for an offset of 100 μm (157.50 ± 17.26 μm) than for offsets of 30 μm (206.48 ± 39.12 μm) and 60 μm (188.82 ± 48.77 μm) (p < 0.001). The accuracy of implant placement was better in the GS than OS group in terms of the entry (OS, 0.229 ± 0.092 mm; GS, 0.169 ± 0.061 mm; p < 0.001), apex (OS, 0.324 ± 0.149 mm; GS, 0.230 ± 0.124 mm; p < 0.001), and depth (OS, 0.041 ± 0.027 mm; GS, 0.025 ± 0.022 mm; p < 0.001). In addition, the entries (30 μm, 0.215 ± 0.044 mm; 60 μm, 0.172 ± 0.049 mm; 100 μm, 0.119 ± 0.050 mm; p < 0.001) were only affected by the amount of offset. These findings indicate that the accuracy of a surgical guide can be improved by directly sealing the groove of the tooth before manufacturing the surgical guide or setting the offset during the design process.

The Influence of Using Different Types of Scan Bodies on the Transfer Accuracy of Implant Position: An In Vitro Study

2021 ◽  
Vol 34 (2) ◽  
pp. 254-260
Author(s):  
Alexander Schmidt ◽  
Jan-Wilhelm Billig ◽  
Maximiliane Schlenz ◽  
Bernd Wöstmann
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Implant Position ◽  
Different Types ◽  
Transfer Accuracy

scholarly journals Enamel loss following ceramic bracket debonding: A quantitative analysis in vitro

2014 ◽  
Vol 85 (4) ◽  
pp. 651-656 ◽  
Author(s):  
Sam N. Suliman ◽  
Terry M. Trojan ◽  
Daranee Tantbirojn ◽  
Antheunis Versluis
Keyword(s):  
Standard Deviation ◽  
Three Dimensions ◽  
Optical Scanner ◽  
Polycrystalline Ceramic ◽  
Tooth Surfaces ◽  
Ceramic Brackets ◽  
Successful Removal ◽  
Ceramic Bracket ◽  
Surface Changes

ABSTRACT Objective:  To measure enamel surface changes after ceramic bracket debonding and after cleanup. Materials and Methods:  Forty extracted teeth were scanned in three dimensions using an optical scanner (baseline). Two ceramic bracket systems were placed (19 metal-reinforced polycrystalline ceramic brackets; 21 monocrystalline ceramic brackets). Seven days later, brackets were debonded and teeth scanned (post-debond). Adhesive remnants and bracket fragments were recorded. Tooth surfaces were cleaned using a finishing carbide bur and scanned again (post-cleanup). Post-debond and post-cleanup scans were aligned with the baseline, and surface changes were quantified. Results were statistically compared using t-tests and Mann-Whitney tests (α  =  .05). Results:  The depth of enamel loss (mean ± standard deviation) post-debond was 21 ± 8 µm and 33 µm and post-cleanup was 28 ± 14 µm and 18 ± 8 µm (P  =  .0191); the post-debond remnant thickness was 188 ± 113 µm and 120 ± 37 µm (P  =  .2381) and post-cleanup was 16 ± 5 µm and 15 µm for polycrystalline and monocrystalline ceramic brackets, respectively. The monocrystalline ceramic brackets predominantly left all adhesive on the tooth; the polycrystalline ceramic brackets were more likely to leave bracket fragments attached. Conclusion:  Both systems allowed successful removal of the brackets with minimal enamel loss. However, the polycrystalline ceramic brackets left more fragments on the tooth, which complicated cleanup efforts.

Preclinical study of PD-0332991 on EBV-positive NPC cell lines and xenografts.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e17506-e17506
Author(s):  
Zhichao Xue
Keyword(s):  
Cell Lines ◽  
Tumor Size ◽  
In Vitro Study ◽  
Preclinical Study ◽  
Drug Study ◽  
Single Drug ◽  
Combination Study ◽  
Scan Data

e17506 Background: Originated from nasopharynx, nasopharyngeal carcinoma is a subtype of head and neck cancer, which is consistently associated with EBV infection. It is prevalent exclusively in south of China, Malaysia and southeast Asia. Previously, there was only one EBV positive cell line, c666-1, for NPC study, the new EBV positive cell lines and xenografts established by our lab recently represent better models for preclinical drug test. The objective of this preclinical study is to evaluate the therapeutic effect of specific CDK4/6 inhibitor PD-0332991 in our new established EBV positive NPC cell lines and Xenografts. Methods: Cell lines were cultured in both 2D and 3D condition, cytotoxic test was conduct by Resazurin in 2D and by cell titer-glo in 3D. Cell cycle was analyzed by Western blot and flow cytometry. In the animal study, PD-0332991 was first used as single drug administrated to xenograft mice daily by oral gavage. Secondly, SAHA as a HDAC inhibitor was used to combine with PD-0332991 in this study, which was i.p. injected into animal every other day. Tumor size, body weight well as micro-pets scan data was recorded. The data from each experiment was analyzed by ANOVA and unpaired t-test for significant drug responses. Results: PD-0332991 was first identified to be effective during in vitro study. Beside single drug effect, when combination with SAHA, a synergistic effect was observed both in vitro and in vivo. In single drug study, PD-0332991 can significantly inhibit tumor growth in 3 of our xenografts (XENO76: P < 0.0001, XENO32: P < 0.0001, XENO23: P = 0.0019). In combination study, through tumor size and micro-pets scan, combination treatment induced significant decrease in tumor size and tumor metabolism states in animal models compare to vehicle, PD-0332991 and SAHA treatment. Conclusions: PD-0332991 is identified to be effective in our preclinical test by using our new established EBV positive cell lines and xenografts, this could be a promising treatment for NPC patients after clinical trial.

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