Table 3 IOS accuracy compared to conventional techniques
From: The direct digital workflow in fixed implant prosthodontics: a narrative review
| References | Indication | Measurement | Study type | Intraoral/extraoral scanner used | Analogue impression type (stone cast accuracy) | Reference scanner | Conclusions |
|---|---|---|---|---|---|---|---|
| Lin et al. [64] | Partially dentate mandible with 2 implants and 4 different angulations (0,15,30 and 45 degrees) | Distance and angulation | In vitro (n = 4) | iTero | PVS (Aquasil) open tray, non-splinted | Cagenix | The amount of divergence between implants significantly affected the accuracy of the milled casts created digitally. The digital technique was more accurate when the implants diverged more. At 0 and 15 degrees of divergence, the digital method resulted in highly significantly less accurate definitive casts. At 30 and 45 degrees of divergence, however, the milled casts showed either no difference or marginal differences with casts created conventionally |
| Mangano et al. [44] |
Partially edentulous maxilla with 3 implants Full edentulous maxilla with 6 implants | 3D surface | In vitro (n = 2) |
Trios 2 (71 μm) CS 3500 (47-63 μm) Zfx Intrascan 117-103 μm) Planscan (233-253 μm) | N/A | Iscan D104I (Imetric3D) |
CS3500 most accurate IOS but no SS compared to TRIOS Refractory Index of PEEK is better than Titanium |
| Flügge et al. [43] |
Partially dentate mandible with 2 implants Partially dentate mandible with 5 implants (Kennedy 1) | Distance and angulation | In vitro (n = 2) |
Trios iTero True Def | N/A | D250 | The precision of IOS decreases with longer distances between scanbodies, especially crossing the midline |
| Fukazawa et al. [45] | Partially dentate mandible with 2 implants (short and long distance) | Distance | In vitro (n = 2) |
Trios 2 (7 and 20 μm) Lava COS (27 μm and 80 μm) True Def (17 μm and 60 μm) Kavo ARCTICA (3 μm and 18 μm) | N/A |
CMM UPMC 550-Sarat |
Trios comparably accurate to Lab scanner and SS more accurate than the other IOS tested For longer distances, IOS accuracy decreases Deviation of up to 100 μm is acceptable |
| Basaki et al. [21] | Partially dentate mandible with 4 implants (Kennedy 1) | Distance | In vitro (n = 1) | iTero (116 μm) | PVS monophase with custom trays (56 μm) | D810 |
PVS impressions were statistically more accurate than IOS Implant angulation did not affect IOS accuracy. Milled 3D casts were less accurate compared to stone casts |
| Imburgia et al. [46] | Partial maxillary arch with 3 implants | 3D surface | In vitro (n = 1) |
Trios 3 (Tr = 50 μm/Pr = 24 μm) CS3600 (Tr = 45 μm/Pr = 24 μm) Omnicam (Tr = 58 μm/Pr = 26 μm) TrueDef (Tr = 61 μm/Pr = 19 μm | N/A | ScanRider |
CS3600 had SS higher trueness compared to other IOS. No SS differences in precision were found Accuracy in the partial arch is higher for all IOS compared to the Full arch situation |
| Chew et al. [24] | Partial jaw with 2 implants and 2 different depths | Distance and angulation | In vitro (n = 2) |
Trios True Def iTero | Polyether mono (custom tray) |
CMM Model Global Silver | Conventional impressions had ss less deviation compared to IOS. Implant depth affected IOS accuracy. Angulation did not affect accuracy |
| Chia et al. [25] | Partial jaw with 2 implants and 3 different angulations | Distance and angulation | In vitro (n = 3) | Trios (31-45 μm) depending on configuration | Polyether mono (custom tray) (18-33 μm) depending on configuration |
CMM Model Global Silver | Distortions were found with conventional and IOS imps. Conventional imps in parallel implants had highest accuracy compared to IOS. Angulation affects IOS accuracy |
| Marghalani et al. [31] | Partially dentate mandibles with 2 implants | 3D surface | In vitro (n = 2) |
Omnicam (33-55 μm) True Def (27-39 μm) | Polyether mono on splinted implant copings (open tray) (26-53 μm) | Activity 880 industrial scanner |
True Def IOS was more accurate but SS difference were not always observed Low deviations < 56 μm |
| Kim et al. [47] | Partially dentate mandible with 6 implant cylinders | Distance | In vitro (n = 1) |
Trios 3 Omnicam CS3600 I500 iTero Element | N/A | StereoSCANneo |
All IOSs exhibit deviations as scanning distance increases from the start position Trios3 and Medit outperformed other IOSs for partially edentulous accuracy |
| Mangano et al. [23] | Partial edentulous maxilla with 2 implants | 3D Surface | In vitro (n = 1) |
Trios 3 (Tr = 28 μm/Pr = 21 μm) CS3600 (Tr = 23 μm/Pr = 17 μm) Omnicam (Tr = 38 μm/Pr = 43 μm) DWIO (Tr = 49 μm/Pr = 34 μm Emerald (Tr = 49 μm/Pr = 29 μm) | N/A | Freedom DOF |
Trios3 and CS3600 were SS more accurate compared to other IOS Accuracy of IOS in implants complete arch is NOT corelated to IOS resolution |
| Motel et al. [65] | Titanium partial model with 3 implants and 3 different scanbody designs and 2 different scan strategies | Distance and 3D surface | In vitro (n = 1) | Trios 3 | N/A | ATOS So4 II |
All in One scan strategy produced more accurate results (71 μm) Emergence profile scan produced lower accuracy (125 μm) In All in One scan strategy, cylindrical scanbodies with flatter surfaces produced more accurate results |
| Alsharbaty et al. [32] | Partially dentate mandibles and maxillae with 2 posterior adjacent implants | Distance | In vivo (n = 28) | Trios 3 |
PVS (Panasil) dual mix, plastic tray/splinted (used as reference) PVS (Panasil) dual mix, plastic tray/non splinted in open and closed tray methods (used for comparison) | CMM (Dea Global) | Conventional open tray pick-up impression was ss more accurate compared to IOS and conventional closed tray pick-up impression |
| Jiang et al. [92] | Partial dentate maxilla and mandible with implants and 2–4 teeth span | 3D surface | In vivo (n = 31) | Trios (27 μm) | Material not provided/splinted, open tray | D800 | The 3D discrepancy between digital and traditional impression is within clinical acceptable range |