Table I.
Landmarks and respective number as marked on facial map in Figure 1
| Number | Landmark |
|---|---|
| 1 | Reference Point |
| 2 | Glabella |
| 3 | R Cheek |
| 4 | L Cheek |
| 5 | Nasal Tip |
| 6 | Subnasale |
| 7 | R Commissure |
| 8 | L Commissure |
| 9 | Soft Tissue Pogonion |
| 10 | R Alar Base |
| 11 | L Alar Base |
| 12 | R Gonion |
| 13 | L Gonion |
| 14 | L Upper Ear |
| 15 | L Tragus |
| 16 | L Lower Ear |
| 17 | R Upper Ear |
| 18 | R Tragus |
| 19 | R Lower Ear |
Figure 1.
Nineteen landmarks marked on a facial map: 1, Reference Point (Ref); 2, Glabella; 3, Right Cheek (R Cheek); 4, Left Cheek (L Cheek); 5, Nasal Tip; 6, Subnasale; 7, Right Commissure (R Commissure); 8, Left Commissure (L Commissure); 9, Soft Tissue Pogonion; 10, Right Alar Base (R Alar Base); 11, Left Alar Base (L Alar Case); 12, Right Gonion (R Gonion); 13, Left Gonion (L Gonion); 14, Left Upper Ear (L Upper ear); 15, Left Tragus (L Tragus); 16, Left Lower Ear (L Lower Ear); 17, Right Upper Ear (R Upper Ear); 18, Right Tragus (R Tragus); 19, Right Lower Ear (R Lower Ear) (Table I).
Figure 2.
Examples of 3D digital models captured by the Bellus3D ARC-7 camera. (A) Frontal View. (B) Angled View.
Figure 3.
A facial Map outlining the reproducibility of pooled digital measurements taken by all examiners. (Legend: Mean Difference of repeated measurements depicted in Dark green = <0.5 mm, yellow = ≥1.0 mm. Grey=Not determinable).
Table II.
Mean difference in measurements of inter-landmark measurements taken on two consecutive digital models of the same sample
| Landmark 1 | Landmark 2 | Mean Difference (mm) | |||
|---|---|---|---|---|---|
| Ref | Glabella | 0.25 | |||
| Glabella | Nose Tip | 0.19 | |||
| Subnasale | Pogonion | 0.54 | |||
| R Cheek | L Cheek | 0.46 | |||
| R Alar | L Alar | 0.38 | |||
| R Commissure | L Commissure | 0.87 | |||
| R Upper Ear | R Middle Ear | N/A | |||
| R Middle Ear | R Lower Ear | 0.57 | |||
| R Cheek | R Gonion | 0.53 | |||
| R Cheek | R Middle Ear | 0.69 | |||
| R Gonion | R Commissure | 0.51 | |||
| L Upper Ear | L Middle Ear | 0.47 | |||
| L Middle Ear | L Lower Ear | 0.37 | |||
| L Cheek | L Gonion | 0.23 | |||
| L Cheek | L Middle Ear | 0.27 | |||
| L Gonion | L Commissure | 1.11 | |||
| Colour Legend: | 0 - 0.5mm | 0.5 - 1.0mm | 1.0 - 1.5mm | 1.5 - 2.0mm | 2.0+mm |
Table III.
The proportion of manual measurements within set threshold deviation values, obtained by a single examiner (categorised by interlandmark variables)
| Inter-landmark measurements | % of measurements within set threshold deviations of: | ||||
|---|---|---|---|---|---|
| Landmark 1 | Landmark 2 | ≤0.5 mm | ≤1.0 mm | ≤1.5 mm | ≤2.0 mm |
| Ref | Glabella | 75% | 88% | 100% | 100% |
| Glabella | Nose Tip | 38% | 75% | 100% | 100% |
| Subnasale | Pogonion | 50% | 63% | 75% | 88% |
| R Cheek | L Cheek | 25% | 50% | 75% | 88% |
| R Alar | L Alar | 25% | 75% | 100% | 100% |
| R Commissure | L Commissure | 25% | 75% | 88% | 88% |
| R Upper Ear | R Middle Ear | 38% | 88% | 88% | 100% |
| R Middle Ear | R Lower Ear | 75% | 100% | 100% | 100% |
| R Cheek | R Gonion | 13% | 38% | 50% | 75% |
| R Cheek | R Middle Ear | 38% | 75% | 88% | 88% |
| R Gonion | R Commissure | 38% | 75% | 88% | 100% |
| L Upper Ear | L Middle Ear | 38% | 75% | 88% | 100% |
| L Middle Ear | L Lower Ear | 63% | 100% | 100% | 100% |
| L Cheek | L Gonion | 13% | 50% | 75% | 75% |
| L Cheek | L Middle Ear | 50% | 75% | 88% | 100% |
| L Gonion | L Commissure | 38% | 50% | 63% | 88% |
Table IV.
The overall proportion of combined manual measurements within set threshold deviation values, obtained by a single examiner
| % of measurements within set threshold deviation of: | |
|---|---|
| ≤0.5 mm | 40% |
| ≤1.0 mm | 72% |
| ≤1.5 mm | 85% |
| ≤2.0 mm | 93% |
Table V.
The proportion of digital measurements within set threshold deviation values, obtained by a single examiner (categorised by interlandmark variables)
| Inter-landmark Variables | % of measurements within set threshold deviations of: | ||||
|---|---|---|---|---|---|
| Landmark 1 | Landmark 2 | ≤0.5 mm | ≤1.0 mm | ≤1.5 mm | ≤2.0 mm |
| Ref | Glabella | 100% | 100% | 100% | 100% |
| Glabella | Nose Tip | 88% | 100% | 100% | 100% |
| Subnasale | Pogonion | 75% | 100% | 100% | 100% |
| R Cheek | L Cheek | 100% | 100% | 100% | 100% |
| R Alar | L Alar | 100% | 100% | 100% | 100% |
| R Commissure | L Commissure | 75% | 100% | 100% | 100% |
| R Upper Ear | R Middle Ear | N/A | N/A | N/A | N/A |
| R Middle Ear | R Lower Ear | 88% | 100% | 100% | 100% |
| R Cheek | R Gonion | 75% | 100% | 100% | 100% |
| R Cheek | R Middle Ear | 100% | 100% | 100% | 100% |
| R Gonion | R Commissure | 88% | 88% | 100% | 100% |
| L Upper Ear | L Middle Ear | 100% | 100% | 100% | 100% |
| L Middle Ear | L Lower Ear | 75% | 88% | 100% | 100% |
| L Cheek | L Gonion | 88% | 100% | 100% | 100% |
| L Cheek | L Middle Ear | 88% | 100% | 100% | 100% |
| L Gonion | L Commissure | 75% | 100% | 100% | 100% |
Table VI.
The overall proportion of combined manual measurements within set threshold deviation values, obtained by a single examiner
| % of measurements within set threshold deviation of: | |
|---|---|
| ≤0.5 mm | 88% |
| ≤1.0 mm | 98% |
| ≤1.5 mm | 100% |
| ≤2.0 mm | 100% |
Table VII.
The mean difference in pooled manual measurements of inter-landmark measurements taken by all examiners
| Landmark 1 | Landmark 2 | Mean Difference (mm) | |||
|---|---|---|---|---|---|
| Ref | Glabella | 0.35 | |||
| Glabella | Nose Tip | 0.64 | |||
| Subnasale | Pogonion | 0.90 | |||
| R Cheek | L Cheek | 1.14 | |||
| R Alar | L Alar | 0.65 | |||
| R Commissure | L Commissure | 0.99 | |||
| R Upper Ear | R Middle Ear | 0.70 | |||
| R Middle Ear | R Lower Ear | 0.28 | |||
| R Cheek | R Gonion | 1.28 | |||
| R Cheek | R Middle Ear | 0.80 | |||
| R Gonion | R Commissure | 0.69 | |||
| L Upper Ear | L Middle Ear | 0.72 | |||
| L Middle Ear | L Lower Ear | 0.47 | |||
| L Cheek | L Gonion | 1.38 | |||
| L Cheek | L Middle Ear | 0.62 | |||
| L Gonion | L Commissure | 0.26 | |||
| Colour Legend: | 0 to 0.5 mm | 0.5 to 1.0 mm | 1.0 to 1.5 mm | 1.5 to 2.0 mm | 2.0+mm |
Table VIII.
The mean difference in pooled digital measurements of inter-landmark measurements taken by all examiners
| Landmark 1 | Landmark 2 | Mean difference (mm) | |||
|---|---|---|---|---|---|
| Ref | Glabella | 0.25 | |||
| Glabella | Nose Tip | 0.19 | |||
| Subnasale | Pogonion | 0.23 | |||
| R Cheek | L Cheek | 0.11 | |||
| R Alar | L Alar | 0.09 | |||
| R Commissure | L Commissure | 0.31 | |||
| R Upper Ear | R Middle Ear | N/A | |||
| R Middle Ear | R Lower Ear | 0.28 | |||
| R Cheek | R Gonion | 0.33 | |||
| R Cheek | R Middle Ear | 0.23 | |||
| R Gonion | R Commissure | 0.29 | |||
| L Upper Ear | L Middle Ear | 0.23 | |||
| L Middle Ear | L Lower Ear | 0.41 | |||
| L Cheek | L Gonion | 0.26 | |||
| L Cheek | L Middle Ear | 0.32 | |||
| L Gonion | L Commissure | 1.16 | |||
| Colour Legend: | 0 to 0.5mm | 0.5 to 1.0mm | 1.0 to 1.5mm | 1.5 to 2.0mm | 2.0+mm |
Figure 4.
A Facial Map outlining the reproducibility of pooled manual measurements taken by all examiners. (Legend: Mean Difference of repeated measurements depicted in Dark green = <0.5 mm, Light green = <1.0 mm, yellow = ≥1.0 mm).
Figure 5.
A Facial Map outlining the reproducibility of measurements taken on two consecutive digital models of the same sample. (Legend: Mean Difference of repeated measurements depicted in Dark green = <0.5 mm, Light green = <1.0 mm, yellow = ≥1.0 mm).
Figure 6.
A Facial Map outlining the deviation of digital measurements from manual measurements on models (at rest). (Legend: Mean Deviations depicted in Dark green = <0.5 mm, Light green = <1.0 mm, Yellow = ≤1.5 mm, Orange = ≤2.00 mm, Red = >2.00 mm).
Table IX.
The mean difference between digital and manual inter-landmark measurements on models (at rest)
| Landmark 1 | Landmark 2 | Mean difference (mm) | |||
|---|---|---|---|---|---|
| L Upper Ear | L Middle Ear | 0.27 | |||
| R Middle Ear | R Lower Ear | 0.52 | |||
| R Cheek | R Middle Ear | 0.56 | |||
| Glabella | Nose Tip | 0.61 | |||
| L Middle Ear | L Lower Ear | 0.61 | |||
| Ref | Glabella | 0.71 | |||
| L Cheek | L Middle Ear | 0.78 | |||
| R Alar | L Alar | 0.94 | |||
| R Cheek | L Cheek | 1.10 | |||
| Subnasale | Pogonion | 1.11 | |||
| R Gonion | R Commissure | 1.13 | |||
| R Commissure | L Commissure | 1.52 | |||
| L Cheek | L Gonion | 1.63 | |||
| R Cheek | R Gonion | 1.76 | |||
| L Gonion | L Commissure | 2.12 | |||
| R Upper Ear | R Middle Ear | N/A | |||
| Colour Legend: | 0 to 0.5 mm | 0.5 to 1.0 mm | 1.0 to 1.5 mm | 1.5 to 2.0 mm | 2.0+mm |
Figure 7.
A Facial Map outlining the deviation of digital measurements from manual measurements on models (during smiling). (Legend: Mean Deviations depicted in Dark green = <0.5 mm, Light green = <1.0 mm, Yellow = ≤1.5 mm, Orange = ≤2.00 mm, Red = >2.00 mm).
Table X.
The mean difference between digital and manual inter-landmark measurements on models (during smiling)
| Landmark 1 | Landmark 2 | Mean difference (mm) | |||
|---|---|---|---|---|---|
| Ref | Glabella | 0.39 | |||
| L Upper Ear | L Middle Ear | 0.31 | |||
| R Middle Ear | R Lower Ear | 0.46 | |||
| Glabella | Nose Tip | 0.57 | |||
| L Middle Ear | L Lower Ear | 0.66 | |||
| R Cheek | R Middle Ear | 0.79 | |||
| L Cheek | L Middle Ear | 0.95 | |||
| R Cheek | R Gonion | 1.24 | |||
| L Cheek | L Gonion | 1.33 | |||
| R Alar | L Alar | 1.44 | |||
| R Cheek | L Cheek | 1.68 | |||
| L Gonion | L Commissure | 1.85 | |||
| R Commissure | L Commissure | 1.88 | |||
| Subnasale | Pogonion | 2.20 | |||
| R Gonion | R Commissure | 2.28 | |||
| R Upper Ear | R Middle Ear | N/A | |||
| Colour Legend: | 0 to 0.5mm | 0.5 to 1.0mm | 1.0 to 1.5mm | 1.5 to 2.0mm | 2.0+mm |
Figure 8.
Bell curve displays that the majority of digital vs calliper deviated measurements were within 2 mm.
Figure 9.
The variability of measurements between landmarks. Green: Measurements between these landmarks had the least variability within and between examiners, for both calliper and digital methods. Grey: Measurements between these landmarks also had the most variability when comparing calliper and digital methods.
Figure 10.
Examples of distortion of stickers, digital landmarks and soft tissues. (A) Hairline (B) Ears concealed by hair. (C) Ear lobe. (D) Lips & teeth during smile. (E) Pogonion, with blurred sticker. (F) L Cheek, with double image.
Appendix 1.
Table containing raw data of difference between the digital and manual inter-landmark measurements (on models at rest).
Appendix 2.
Table containing raw data of difference between the digital and manual inter-landmark measurements (on models during smiling).