Abstract
Purpose
To evaluate the scanning strategies affecting the accuracy of virtual interocclusal records (VIR) in partially edentulous arches using an intraoral scanner in vitro.
Methods
A reference model of a partially edentulous arch with implant analogs in positions 45,46 and 47 was constructed. Six pairs of 1-mm diameter metal beads were placed on the gingival tissue as markers for measurement. Four scanning strategies were tested: Quadrant-arch Scan (group 1), Quadrant-arch Scan with Auxiliary occlusal devices (AOD) (group 2), Full-arch Scan (group 3), Full-arch Scan with AOD (group 4). The model was digitalized with a lab scanner as a reference and 15 scans were obtained for each group. The accuracy of VIR was assessed by comparing the experiment data to the reference digital model.
Results
The mean surface deviations of VIR for Groups 1–4 were 89.4 ± 105.2 μm,95.6 ± 132.8 μm,152.3 ± 159.7 μm and 107.6 ± 138.2 μm respectively. Quadrant-arch scans resulted in lower errors of VIR than full-arch scan (P < 0.001). There was a significant interaction between the AOD and scanning span (P = 0.017). The Quadrant-arch scan with AOD (group 2) produced the least error in the distally extended edentulous area.
Conclusions
Quadrant-arch scans showed better accuracy of VIR than full-arch scans across all tooth positions. The combination of AOD and quadrant-arch scan further enhances VIR accuracy in distally extended edentulous areas.
Keywords: Auxiliary occlusal devices, Scanning spans, Virtual interocclusal records, Digital impression, Multiple implants
Introduction
Obtaining accurate VIR is critical in prosthetic dentistry. The introduction of intraoral scanners (IOSs) has led to a gradual transition from conventional occlusal record [1] toward virtual interocclusal records (VIR). VIR involve aligning the digital maxillary and mandible arches using digital buccal images with a computer algorithm to simulate the maxillo-mandibular relationship [2, 3]. These records play an essential role in dental diagnosis, treatment planning, and the fabrication of dental prostheses [4]. However, the scanning process with IOS involves stitching multiple images with overlapping areas, leading to potential inaccuracies [5]. Factors such as scanner brands, imaging technology, scan quality, best-fit alignment, software algorithms, intermesh penetrations can impact the accuracy of VIR [4, 6, 7]. Understanding how these factors influence accuracy is essential for optimizing IOS scanning strategies.
It has been shown that VIR accuracy correlates strongly with the number of missing teeth. In the previous studies VIR was highly accurate in the complete dentate arch [8]. The accuracy decreases significantly in cases with multiple missing teeth due to the lack of identifiable landmarks for scanners [9, 10]. Consequently the auxiliary occlusal devices (AOD) were applied in partially edentulous area to enhance VIR accuracy [11, 12]. Previous studies have demonstrated that auxiliary devices attached to multiple scanbodies improved the accuracy of implant positions in edentulous arches [13–16]. Healing abutments, serving as AOD, improved VIR accuracy in a lab study [11]. A clinical study [12] showed that the digital workflow using AOD required fewer occlusal crown adjustments compared to conventional workflow. However, the specific effect of AOD on improving the accuracy of VIR in partially edentulous arch remains unclear [11].
The choice of quadrant-arch scan versus complete-arch scan may also impact the VIR accuracy. Previous researches have presented conflicting findings on whether full-arch scans exhibit superior accuracy of occlusal registration compared to quadrant-arch scans [17–21]. Some studies [19, 20] have shown that for the fully dentate arch, scanning two lateral and frontal sections as occlusal records had the best accuracy compared to other scanning spans, suggesting that full-arch scan might offer better accuracy for VIR. However, the other study [18] has reported no significant differences between occlusal registrations obtained from full-arch and quadrant-arch scans. Additionally, some research [21] has demonstrated that the deviation of VIR on right posterior region increased with larger scanning spans, favoring the quadrant-arch scan in terms of occlusal registration. All these studies focused on fully dentate arches, leaving a gap in understanding the impact of scanning span on VIR accuracy in partially edentulous arches. Given that IOS accuracy tends to decrease with larger scanning spans while VIR accuracy improves with larger areas due to computer algorithms, this study aims to investigate which effect predominates by employing both full-arch and quadrant-arch scan methods.
Besides, the accuracy of VIR might also fluctuate across the different positions of the dental arch. Previous studies [9, 11] showed that there was a significant increase of distortion of digital occlusion from anterior to posterior tooth positions when using the intra-oral scanners. However, the interaction effect of the tooth position and other factors remains unclear.
The purpose of the present in vitro study is to assess the impact of AOD, scanning spans (full-arch scan and quadrant-arch scan) and the tooth positions on the accuracy of VIR in the partially edentulous model by using an IOS (TRIOS 4, wireless, 3Shape). The null hypothesis was that there would be no difference on the accuracy of VIR, regardless of the use of AOD, the scanning spans or tooth positions.
Materials and methods
The workflow of this in vitro study was illustrated in Fig. 1.
Fig. 1.
The workflow. AOD: Auxiliary Occlusal Devices
Model Preparation
A reference model representing a partially edentulous arch was fabricated using a complete dentate standard model (Prosthetic Restoration Jaw Model; Nissin Dental). Specifically, teeth 45, 46, and 47 were extracted from the mandibular arch, and three implant analogs were appropriately positioned in the resultant sockets. Subsequently, maxillary and mandibular stone models (Die-stones Type 4, Dentona) were cast from the reference model, with the gingival tissue simulated using pink cold-curing polymethylmethacrylate material (Gingitech Refill, Ivoclar Vivadent) around the implant analogs. The maxillary and mandibular models were then mounted on a semi-adjustable articulator (SAM®3, SAM) in the maximum intercuspation position (MIP) using class III dental stone (ZERO arti, Dentona). To ensure uniform occlusal contacts throughout the arch, the occlusal surfaces of the teeth were adjusted utilizing 8-mm-thick articulating film (Shimstock Occlusion Foil; Almore Mfg Co). Six pairs of 1-mm diameter metal beads (304 Steel Bead, Fuzhanggui) were attached to the gingival tissue, arranged sequentially from the canine to the second molar. Subsequently, the entire articulator with maxillary and mandibular casts in MIP was placed in a laboratory dental scanner (E4; 3 Shape) and scanned in accordance with the manufacturer’s guidelines. The manufacturer of the laboratory scanner reports a scanning accuracy of < 4 μm, adhering to ISO 12,836 standards.
IOS scanning
Four scanning strategies were implemented as follows:
-
A)
Full-arch scan;
-
B)
Full-arch scan with auxiliary occlusal devices (AOD);
-
C)
Quadrant-arch scan;
-
D)
Quadrant-arch scan with AOD.
A single intraoral scanner (TRIOS 4;wireless;3shape) was used through the whole study. All intraoral digital scans were conducted in a consistently illuminated environment to ensure minimal fluctuations in light intensity. Calibration procedures for the intraoral scanner were meticulously followed in accordance with the manufacturer’s guidelines. Data collection procedures for acquiring maxillary and mandibular digital scans, as well as virtual occlusal records adhered to the prescribed scanning pattern recommended by the IOS manufacturer. During full-arch scans, the scanning sequence commenced from the edentulous area and progressed towards the dentated region, traversing from the occlusal aspect to the buccal and subsequently to the lingual aspect. Bilateral virtual occlusal records were obtained and utilized for alignment. Similarly, quadrant-arch scans initiated from the distal end towards the ipsilateral central incisor, followed by the occlusal, buccal, and lingual directions. Only a single lateral occlusal record was employed for alignment in quadrant-arch scan. The auxiliary occlusal devices (AOD) were sandblasted titanium posts with convex features (Fig. 2). These devices varied in height from 5 mm to 10 mm, extending from the gingival margin to the antagonist teeth to offer more prominent anatomical landmarks in the edentulous area. AOD of appropriate height for the occlusal space were affixed to implant analogs. In scanning strategies without AOD, healing abutments measuring 3 mm in height were affixed to the implant analogs, after which the intraoral scanner was utilized as per the manufacturer’s instructions. No manual alignment was performed after auto-alignment by software program.
Fig. 2.
Custom auxiliary occlusal devices with various height
The sample size was calculated based on preliminary data from similar studies [10, 11], utilizing sample size software (PASS 15, NCSS Statistical Software) to ensure adequate statistical power. With the power set at 80% and an alpha level of 0.05, the analysis determined that a minimum of 4 repeated scans per strategy was necessary. To enhance the reliability of the findings, 15 repeated scans were conducted for each group. Each scanning strategy was repeated 15 times by one proficient operator to ensure consistency and reliability.
Maxillo-mandibular relationship analysis
The maxillo-mandibular relationship is three-dimensional, but the vertical dimension is particularly clinically relevant, as it directly impacts occlusion. Therefore, the accuracy of the VIR is typically assessed by measuring the linear distances between pairs of markers on the maxilla and mandible, as suggested by previous references [8, 10].
Standard tessellation language (STL) files, including maxillary and mandibular digital casts, were exported from the IOS and imported into a surface matching software program (Geomagic Control X, v2020.0.1; 3D Systems Inc). The measurements of the distance between two metal beads were taken into two steps: first, the center of each bead was identified by selecting the spherical surface, with the center automatically calculated by the software. Then, the distance between the centers of each bead pair was measured (Fig. 3). Similarly, data from reference digital model obtained from the laboratory scanner were also measured accordingly 5 times and the average value was adopted as the reference.
Fig. 3.
Digital casts with linear measurement
All distance measurements were operated and recorded by one examiner. To test the intra-examiner reliability, 16 pairs of markers were randomly selected and measured twice in two separated days. The interclass correlation coefficient (ICC) were 0.96 and 0.92, respectively.
Statistical analysis
The experimental data were analyzed utilizing the SV26 software program (IBM SPSS Statistics 26). Normality of the data was verified using the Shapiro-Wilk test (P < 0.05). Subsequently, a three-way analysis of variance (ANOVA) was conducted to investigate the impact of three factors, namely scanning spans, auxiliary occlusal device (AOD), and maker position, on the surface deviation of VIR between IOS and the reference. The significance level was set at α = 0.05 for all statistical tests.
Results
The overall mean surface deviations of virtual interocclusal records (VIR) between intraoral scanners (IOS) and the reference was listed by groups. See Table 1.
Table 1.
Surface deviation of VIR (Mean±Standard deviation)(μm) AOD: Auxiliary Occlusal Device
| Scanning Strategy | Quadrant-arch Scan No AOD |
Quadrant-arch Scan AOD |
Full-arch Scan No AOD |
Full-arch Scan AOD |
|---|---|---|---|---|
| Marker position 1 | 68.1±83.6 | 118.7±93.4 | 0.2±69.6 | 17.9±70.2 |
| Marker position 2 | 66.2±50.0 | 119.6±60.7 | 80.1±44.1 | 74.5±36.4 |
| Marker position 3 | 70.6±32.5 | 94.5±52.0 | 127.1±59.3 | 81.6±29.2 |
| Marker position 4 | 101.6±53.0 | 89.6±67.0 | 183.7±69.7 | 121.0±59.1 |
| Marker position 5 | 12.6±89.4 | -31.5±133.1 | 107.1±77.5 | 36.6±90.4 |
| Marker position 6 | 217.1±153.7 | 182.5±219.5 | 415.7±179.9 | 314.2±202.2 |
| Mean | 89.4±105.2 | 95.6±132.8 | 152.3±159.7 | 107.6±138.2 |
The three-way revealed significant main effects for scanning spans and marker position on the surface deviation of VIR (P < 0.001), while the effect of auxiliary occlusal device (AOD) was not significant (P = 0.071 > 0.05).
The main effect of scanning spans was significant (P < 0.001). The mean surface deviation of VIR were 92.5 ± 119.5 μm in quadrant-arch scanning and 130.0 ± 150.6 μm in full-arch scanning, indicating that the choice of scanning spans significantly influenced the surface deviation of VIR. Specifically, VIR generated using quadrant-arch scanning exhibited lower surface deviations compared to those generated using full-arch scanning irrespective of the presence or absence of AOD.
Similarly, the main effect of marker positions was found to be significant, P < 0.001. This implies that VIR accuracy varies across different marker positions, see Fig. 4. Notably, VIR generated from positions 6, corresponding to the distal and edentulous areas, exhibited significantly higher surface deviations compared to those obtained from positions 1, 2, 3, representing the mesial and dentated regions.
Fig. 4.
Surface deviation of virtual interocclusal records (VIR)
However, AOD doesn’t function as a significant main effect on the surface deviation of VIR, P = 0.071.
There was an interaction effect between any two of the three factors (scanning spans * AOD P = 0.017, scanning spans * marker position P < 0.001, and AOD * marker position P = 0.023). The mean absolute error of VIR were 89.4 ± 105.2 μm in quadrant-arch scanning and 152.3 ± 159.7 μm in full-arch scanning without AOD respectively, while the mean surface deviation of VIR were 95.6 ± 132.8 μm in quadrant-arch scanning and 107.6 ± 138.2 μm in full-arch scanning with AOD respectively. Specifically, when examining marker position 6 representing the most distal edentulous area, it was observed that quadrant-arch scanning in conjunction with AOD resulted in the least VIR error (Surface deviation = 182.5 ± 219.5 μm) compared to alternative scanning methods with surface deviation ranging from 217.1 μm to 415.7 μm. See Fig. 4.
Discussion
This study aimed to evaluate the influence of the auxiliary occlusal devices (AOD) and scanning spans on the accuracy of virtual interocclusal records (VIR) in partially edentulous arches using an intraoral scanner.
Interestingly, this study’s findings contradict those of Jeong et al. [18] and Solaberrieta et al. [19], who either favored complete-arch scans over quadrant-arch scans for occlusal registration accuracy or found no significant differences between the two methods. This discrepancy might stem from the focus of the studies on complete dentate arches, whereas this research specifically targets partially edentulous arches. This suggests that the impact of scanning spans on the accuracy of VIR is more pronounced in cases involving partially edentulous arches. The difference might also be attributed to the distinct computer algorithms used to construct the virtual VIR, which depend on the available anatomical landmarks. However, further investigation is required to fully understand these mechanisms.
The findings revealed that while the main effect of the AOD was generally not significant, it displayed particular significance for the distal edentulous areas (positions 4 and 6), leading to the partial rejection of the second null hypothesis. Previous studies have indicated that long-span partially edentulous area has negative impact on the accuracy of VIR [9, 10]. Additionally, several studies have demonstrated that the utilization of AOD enhances the accuracy of digital impression of multiple implants on edentulous arch with IOS [13, 22–24]. Moreover, a few studies have underscored the efficacy of AOD in enhancing the precision and efficiency of VIR [4, 12, 25]. While the design of AODs in previous studies varied in shape and material, the common goal was to provide sufficient landmarks without obstructing the achievement of maximum intercuspation position (MIP). In this investigation, the AODs were titanium posts of various heights, selected based on the available occlusal space. Although the overall accuracy of VIR remained relatively consistent regardless of the utilization of AOD, notable enhancements in accuracy were observed specifically in edentulous areas where implant-supported restorations were situated.
The results further revealed a significant main effect of marker positions. Jin et al. [25] reported an increasing distortion of VIR from anterior to posterior tooth positions in partially edentulous arches, resulting in decreased accuracy of VIR in distal edentulous areas. Consistent with this trend, this study found significantly higher surface deviations in VIR generated from positions 4 and 6 compared to positions 1, 2, 3, and 5. While the overall pattern of decreased accuracy in edentulous areas aligns with prior research, variations in VIR were observed in specific local areas, such as position 5, potentially attributed to differences in intraoral scanner brands and corresponding computer algorithms utilized across studies.
The surface deviations observed in this study fall within the range of 200–400 μm, which is clinically acceptable based on prior research. Previous studies [26, 27] on implant-supported restorations have indicated that occlusal adjustments of crowns typically range from 212.7 to 279.67 μm with a chairside adjustment time of 8.4 to 12.7 min in digital workflows, and from 330.7 to 479.59 μm with 12.3 to 19.75 min in conventional workflows. Therefore, surface deviations within 200–400 μm are generally associated with chairside adjustment times of approximately 10–20 min. While these deviations are within a clinically acceptable range, excessive occlusal adjustments can still negatively affect the morphology and ideal occlusion of crowns. Thus, achieving the highest possible accuracy is critical. When considering strategies for enhancing scanning accuracy in clinical practice, priority should be given to optimizing the scanning spans. Specifically, for the distally extended edentulous area, the combination of quadrant-arch scan with AOD yielded the lowest error rates. This highlights the significance of incorporating quadrant-arch scan with AOD during digital impression procedures for multiple-implant supported restorations to achieve the most accurate occlusion.
This study has several limitations. Firstly, as an in vitro study, it does not fully replicate real oral conditions, where factors such as blood and saliva could unpredictably impact the scanning process. Secondly, the investigation solely focused on determining whether the AOD significantly influenced the accuracy of VIR, without considering potential variations in the effects of different types of AOD. Future research could explore this aspect further. Thirdly, the study utilized only one IOS, whereas different IOSs may exhibit varying accuracies due to differences in data capture modes and software algorithms. This variability could potentially influence the study results. Finally, it remains unclear whether the presence of the metal bead itself may affect the accuracy of the virtual VIR, considering it serves as a geometric landmark. Future research should explore different types of AOD and in vivo conditions to validate these findings.
Conclusions
Quadrant-arch scan consistently showed better accuracy of VIR than full-arch scan. While the AOD itself did not significantly influence accuracy, the combination of AOD and quadrant-arch scan further enhances VIR accuracy in distally extended edentulous areas.
Acknowledgements
The authors would like to thank Dong Zhou, the dental technician from Department of Oral Implantology at Peking University School and Hospital of Stomatology in Beijing for his support in techniques and materials.
Author contributions
S.R. and X. J. concepted the idea. C.Y. and C.Z. conducted the experiment, Y. W. collected and analyzed data. C.Y. wrote the main manuscript text. All authors reviewed the manuscript.
Funding
The study was supported in part by Program for New Clinical Techniques and Therapies of Peking University School and Hospital of Stomatology (PKUSSNCT-23A03) and Beijing Natural Science Foundation (L232111).
Data availability
The datasets used and/or analyzed during the current study is available from the corresponding author on reasonable request.
Declarations
Ethics approval and consent to participate
Not applicable.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Can Yu and Chengzhe Zhang contributed to the work equally and should be regarded as co-first authors.
Contributor Information
Xi Jiang, Email: jiangxi2003@bjmu.edu.cn.
Shuxin Ren, Email: shuxin.ren@hotmail.com.
References
- 1.Alghazzawi TF. Advancements in CAD/CAM technology: options for practical implementation. J Prosthodont Res. 2016;60:72–84. [DOI] [PubMed] [Google Scholar]
- 2.Myers ML. Centric relation records—historical review. J Prosthet Dent. 1982;47:141–5. [DOI] [PubMed] [Google Scholar]
- 3.Pokorny PH, Wiens JP, Litvak H. Occlusion for fixed prosthodontics: a historical perspective of the gnathological influence. J Prosthet Dent. 2008;99:299–313. [DOI] [PubMed] [Google Scholar]
- 4.Chinam N, Bekkali M, Kallas M, Li J. Virtual occlusal records acquired by using intraoral scanners: a review of factors that influence maxillo-mandibular relationship accuracy. J Prosthodont. 2023;32:192–207. [DOI] [PubMed] [Google Scholar]
- 5.Wu HK, Wang J, Chen G, Huang X, Deng F, Li Y. Effect of novel prefabricated auxiliary devices attaching to scan bodies on the accuracy of intraoral scanning of complete-arch with multiple implants: an in-vitro study. J Dent. 2023;138:104702. [DOI] [PubMed] [Google Scholar]
- 6.Pesce P, Bagnasco F, Pancini N, Colombo M, Canullo L, Pera F et al. Trueness of Intraoral Scanners in Implant-Supported Rehabilitations: An In Vitro Analysis on the Effect of Operators’ Experience and Implant Number. 2021. [DOI] [PMC free article] [PubMed]
- 7.Canullo L, Colombo M, Menini M, Sorge P, Pesce P. Trueness of Intraoral scanners considering Operator experience and three different Implant scenarios: a preliminary Report. Int J Prosthodont. 2021;34:250–3. [DOI] [PubMed] [Google Scholar]
- 8.Revilla-León M, Alonso Pérez-Barquero J, Zubizarreta-Macho Á, Barmak AB, Att W, Kois JC. Influence of the number of Teeth and Location of the virtual Occlusal Record on the Accuracy of the Maxillo-Mandibular Relationship obtained by using an Intraoral scanner. J Prosthodont. 2023;32:253–8. [DOI] [PubMed] [Google Scholar]
- 9.Lee Y-C, Kim J-E, Nam N-E, Shin S-H, Lim J-H, Lee K-W, et al. Influence of Edentulous conditions on Intraoral scanning accuracy of virtual interocclusal record in Quadrant scan. Appl Sci. 2021;11:1489. [Google Scholar]
- 10.Ren S, Morton D, Lin W-S. Accuracy of virtual interocclusal records for partially edentulous patients. J Prosthet Dent. 2020;123:860–5. [DOI] [PubMed] [Google Scholar]
- 11.Jin G, Kim J-E, Nam N-E, Shin S-H, Shim J-S. Accuracy improvement of Intraoral scanning and Buccal Bite Registration using Healing Abutment as landmarks: an in Vitro Study. Appl Sci. 2020;11:318. [Google Scholar]
- 12.Ren S, Jiang X, Di P. Auxiliary occlusal devices for IO scanning in a complete digital workflow of implant-supported crowns: a randomized controlled trial. BMC Oral Health. 2024;24:374. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Iturrate M, Eguiraun H, Etxaniz O, Solaberrieta E. Accuracy analysis of complete-arch digital scans in edentulous arches when using an auxiliary geometric device. J Prosthet Dent. 2019;121:447–54. [DOI] [PubMed] [Google Scholar]
- 14.Iturrate M, Eguiraun H, Solaberrieta E. Accuracy of digital impressions for implant-supported complete-arch prosthesis, using an auxiliary geometry part-An in vitro study. Clin Oral Implants Res. 2019;30:1250–8. [DOI] [PubMed] [Google Scholar]
- 15.Pan Y, Tsoi JKH, Lam WY, Zhao K, Pow EH. Improving intraoral implant scanning with a novel auxiliary device: an in-vitro study. Clin Oral Implants Res. 2021;32:1466–73. [DOI] [PubMed] [Google Scholar]
- 16.Arikan H, Muhtarogullari M, Uzel SM, Guncu MB, Aktas G, Marshall LS, et al. Accuracy of digital impressions for implant-supported complete-arch prosthesis when using an auxiliary geometry device. J Dent Sci. 2023;18:808–13. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Edher F, Hannam AG, Tobias DL, Wyatt CCL. The accuracy of virtual interocclusal registration during intraoral scanning. J Prosthet Dent. 2018;120:904–12. [DOI] [PubMed] [Google Scholar]
- 18.Jeong Y, Kim Y-K, Shim J-S, Lee H. 3D analysis of occlusal registration through geometry embedded library matching between quadrant and full-arch digital impression. Clin Oral Investig. 2023;27:3771–8. [DOI] [PubMed] [Google Scholar]
- 19.Solaberrieta E, Garmendia A, Brizuela A, Otegi JR, Pradies G, Szentpétery A. Intraoral Digital Impressions for Virtual Occlusal Records: section quantity and dimensions. Biomed Res Int. 2016;2016:1–7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Eneko S, Arias A, Brizuela A, Garikano X, Pradies G. Determining the requirements, section quantity, and dimension of the virtual occlusal record. J Prosthet Dent. 2016;115:52–6. [DOI] [PubMed] [Google Scholar]
- 21.Mei J, Ma L, Chao J, Liu F, Shen J. Three-dimensional analysis of the outcome of different scanning strategies in virtual interocclusal registration. J Adv Prosthodont. 2022;14:369. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 22.Roig E, Roig M, Garza LC, Costa S, Maia P, Espona J. Fit of complete-arch implant-supported prostheses produced from an intraoral scan by using an auxiliary device and from an elastomeric impression: a pilot clinical trial. J Prosthet Dent. 2022;128:404–14. [DOI] [PubMed] [Google Scholar]
- 23.Kim J-E, Amelya A, Shin Y, Shim J-S. Accuracy of intraoral digital impressions using an artificial landmark. J Prosthet Dent. 2017;117:755–61. [DOI] [PubMed] [Google Scholar]
- 24.Andriessen FS, Rijkens DR, van der Meer WJ, Wismeijer DW. Applicability and accuracy of an intraoral scanner for scanning multiple implants in edentulous mandibles: a pilot study. J Prosthet Dent. 2014;111:186–94. [DOI] [PubMed] [Google Scholar]
- 25.Jin G, Kim J-E, Nam N-E, Shin S-H, Shim J-S. Accuracy improvement of Intraoral scanning and Buccal Bite Registration using Healing Abutment as landmarks: an in Vitro Study. Appl Sci. 2021;11:318. [Google Scholar]
- 26.Zhang Y, Tian J, Wei D, Di P, Lin Y. Quantitative clinical adjustment analysis of posterior single implant crown in a chairside digital workflow: a randomized controlled trial. Clin Oral Implants Res. 2019;30:1059–66. [DOI] [PubMed] [Google Scholar]
- 27.Ren S, Jiang X, Lin Y, Di P. Crown Accuracy and Time Efficiency of Cement-retained Implant‐supported restorations in a complete Digital Workflow: a Randomized Control Trial. J Prosthodont. 2022;31:405–11. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets used and/or analyzed during the current study is available from the corresponding author on reasonable request.