Table 4. Results of the included studies.
| Study | Main Outcomes | Secondary Outcomes | Main Results | Secondary Results |
|---|---|---|---|---|
| Almukhtar et al., PLoS One (2014) |
Mean absolute distance of surface models in unchanged areas (anterior cranial base for hard tissue and forehead for soft tissue models): 1. VBR hard; 2. VBR soft; 3. SBR hard; 4. SBR soft | Correlation between VBR and SBR results on hard and soft tissues | Mean absolute distances (mm): 1. 0.050 ± 0.206; 2. 0.294 ± 0.334; 3. 0.047 ± 0.259; 4. 0.230 ± 0.561 VBR hard - SBR hard (p = 0.392) VBR soft - SBR soft (p = 0.243) |
VBR hard - SBR hard: r = 0.886 VBR soft - SBR soft: r = 0.126 |
| Bazina et al., Am J Orthod Dentofacial Orthop (2018) |
1. Reproducibility of the Dolphin technique 2. Agreement with the ITK-Snap+3D Slicer assessed through the mean differences at 7 areas: a. Nasion area; b. A-point area; c. Right zygomatic area; d. Left zygomatic area; e. Right gonial angle; f. B-point area; g. Left gonial angle |
NA | 1. ICC = 0.964 (0.941 - 0.978) 2. Mean differences (mm) = a. 0.099 ± 0.072; b. 0.188 ± 0.110; c. 0.113 ± 0.086; d. 0.092 ± 0.057; e. 0.210 ± 0.136; f. 0.189 ± 0.101; g. 0.169 ± 0.082 |
NA |
| Cevidanes et al., Dentomaxillofaci Radiol (2005) |
Inter-operator agreement on surface distance measurements of 3D models at 3 mandibular regions: 1. Anterior mandibular ramus, 2. Posterior mandibular ramus, 3. Condyles | NA | Surface distances (mm): 1. 0.25 ± 0.11; 2. 0.13 ± 0.05; 3. 0.09 ± 0.05 | NA |
| Cevidanes et al., Am J Orthod Dentofacial Orthop (2009) |
Inter-operator agreement on surface distance measurements of 3D models at 9 regions: 1. Zygomatic process, 2. Anterior maxilla, 3. Chin, 4. Right anterior condyle, 5. Right posterior condyle, 6. Left anterior condyle, 7. Left posterior condyle, 8. Mandibular inferior border, 9 Soft-tissue upper lip | NA | Surface distances (mm): 1. 0.1–0.4; 2. 0.2 - 0.5; 3. 0.1 - 0.4; 4. 0.0 - 0.3; 5. 0.1–0.4; 6. 0.0–0.3; 7. 0.0–0.4; 8. 0.2 - 0.4; 9. 0.3 - 0.5 | NA |
| Gkantidis et al., PLoS One (2015) |
A. Trueness (overall deviation of surface models at unchanged areas: AC + F) B. Intra-operator agreement (on measured structural changes at four corresponding landmarks) of different superimposition techniques: 1. 3P; 2. 1Z; 3. BZ; 4. AC; 5. AC+F C. Inter-operator agreement assessed as described above |
NA | A. Trueness (median values of the 3 operators in mm): 1. 0.79 - 1.01; 2. 1.42 - 1.76; 3. 0.31 - 0.57; 4. 0.35 - 0.52; 5. 0.07 - 0.11 (p = 0.0002) B. p = 0.854 C. p = 0.661; r > 0.91 for all except 3P |
NA |
| Ghoneima et al., Orthod Craniofac Res (2017) |
A. Reproducibility of each superimposition technique B. Mean absolute distance between manually located landmarks on superimposed duplicated scans (ACP, Ba-x, Ba-y, PNS-y, B point-x, Me-x, U1-x, L1-x) |
NA |
Surface-based and Voxel-based superimposition methods using the anterior cranial base as reference seem to be reproducible whereas Landmarks-based superimposition is less reproducible. | NA |
| Häner et al., Orthod Craniofac Res (2019) |
1. Trueness of the voxel-based superimposition assessed through visual inspection of corresponding reference structures 2. Intra-operator reproducibility assessed through the mean absolute distance (MAD) of the repeatedly superimposed T0 surface models measured in the following areas: N-point, A-point, Pogonion, Right and Left zygomatic arch, Right and left gonial angle 3. Inter-operator reproducibility assessed as described above |
Segmentation effect (manual and automatic) assessed as the intra- and interoperator reproducibility | 1. In all cases, visual inspection of the superimposed T0-T1 volumes presented adequate overlap 2. MAD (0.06 - 0.16 mm). In very few cases, it exceeded 0.5 mm and never 1 mm 3. MAD (0.15 - 0.24 mm). In few cases, it exceeded 0.5 mm and never 1.5 mm |
The median segmentation error ranged from 0.05 - 0.12 mm. The biggest segmentation error was found at A-point (0.3 mm) |
| Koerich et al., Int J Oral Maxillofac Surg (2016) |
A. Intra-operator agreement on surface distance measurements (RMSD) of serial 3D models at 2 regions of the maxilla and 3 regions of the mandible (average difference) B. Inter-operator agreement assessed as described above |
NA |
A.1 Intra-operator agreement (mm): NA A.2 Intra-operator agreement (mm). Maxilla: 0.183 - 0.184, Mandible: −0.005 - 0.001 B.1 Inter-operator agreement (mm). Maxilla: 0.087 - 0.098, Mandible: 0.183 - 0.184 B.2 Inter-operator agreement (mm). Maxilla: 0.072 - 0.092, Mandible: 0.087 - 0.105 |
NA |
| Koerich et al., Angle Orthod (2017) |
Inter-operator agreement on surface distance measurements (RMSD) at 5 mandibular regions: 1. Right mandible, 2. Chin, 3. Left mandible, 4. Right ramus, and 5. Left ramus, located at the outer surface of the mandible | NA | Surface distances (mm): 1. 0.11 ± 0.12; 2. 0.14 ± 0.1; 3. 0.11 ± 0.16; 4. 0.33 ± 0.29; 5. 0.36 ± 0.33 | |
| Lemieux et al., Am J Orthod Dentofacial Orthop (2014) |
Amount of expansion at the levels of the first premolars (from tip to tip of each buccal cusp) and the first molars (from tip to tip of each mesiobuccal cusp) on 1. plaster models and 2. 3D plane superimposition | Landmark identification reproducibility through ICC | Mean distances measured between premolars (mm): 1. 2.97 ± 2.12; 2. 3.06 ± 1.97 Mean distances measured between molars (mm): 1. 4.18 ± 1.62; 2. 4.28 ± 1.61 |
ICC > 0.924, 0.992, 0.973 in the x, y, and z axes respectively |
| Nada et al., PLoS One (2011) |
Mean absolute distance of surface models on the following stable areas: a. anterior cranial base (CB); b. forehead (FH); c. left zygomatic arch (ZL); d. right zygomatic arch (ZR) | A. Mean differences between the two superimposition techniques B. Mean differences between repeated AC superimposition measurements C. Mean differences between repeated LZ superimposition measurements |
Mean distances measured between the models (mm): 1. 0.20 - 0.37 (SD: 0.08 - 0.16); 2. 0.20 - 0.45 (SD: 0.09 - 0.27) | A. Mean differences (mm): a. 0.12 ± 0.19; b. 0.19 ± 0.12; c. 0.15 ± 0.18; d. −0.17 ± 0.13 B. Mean differences (mm): a. 0.02 ± 0.09; b. 0.01 ± 0.07; c. −0.07 ± 0.12; d. 0.04 ± 0.09 C. Mean differences (mm): a. −0.07 ± 0.25; b. 0.04 ± 0.24; c. 0.14 ± 0.10; d. 0.04 ± 0.09 |
| Nguyen et al., Am J Orthod Dentofacial Orthop (2017) |
1. Absolute mean surface distance of the registered models on plates and screws, calculated at 3 regions: a. Chin, b. Symphysis, c. Lower contour of the third molar crypt 2. Reproducibility of the combined chin+symphysis regions measured through ICC and mean absolute distances of the entire surface of T2 registered mandibular models by two operators |
NA | 1. Absolute mean surface distance (mm): a. 0.37 ± 0.16; b. 0.40 ± 0.14; c. 1.94 ± 0.06 2. ICC = 0.998 (95% CI [0.995–1.000]) |
NA |
| Ruellas et al., Am J Orthod Dentofacial Orthop (2016a) |
Differences between corresponding landmark distances from T0-T1 measured through the two superimpositions | A. Precision and B. reproducibility of each technique measured as differences in Euclidean distances of corresponding landmarks | Mean differences (mm): 0.35 - 0.39 (SD: 0.23 - 0.24) | A. Mean differences (mm): 0.36 - 0.42 (SD: 0.21 - 0.24) B. Mean differences (mm): 0.31 - 0.44 (SD: 0.16 - 0.28) |
| Ruellas et al., PLoS One (2016b) |
Difference of corresponding landmark distances between T0-T1 calculated through superimposition on 3 different reference regions, compared to direct measurements of landmark movements from a point considered stable | NA | NA (Mean values provided were outside of the Limits of Agreement range) | NA |
| Weissheimer et al., Int J Oral Maxillofac Surg (2015) |
Visual inspection of the superimposition technique and trueness assessment through visualisation of 3D colour maps | Visual inspection of the effectiveness of the technique through superimposition of reoriented identical models | Highest distance between corresponding anterior cranial base references is less than 0.5 mm for growing and non-growing patients | Highest distance between identical, reoriented anterior cranial bases was less than 0.25 mm |