Table 3 Assessment of image noise and artefacts in the bone and soft tissue for cone-beam (CBCT) and multidetector CT (MDCT) by two radiologists (R1, R2) using a five-point Likert scale
Score | Regular-dose CBCT | Low-dose CBCT | Regular-dose MDCT | Low-dose MDCT | |||||
|---|---|---|---|---|---|---|---|---|---|
R1 | R2 | R1 | R2 | R1 | R2 | R1 | R2 | ||
Noise in the bone | 5 | 16 (100.0) | 14 (87.5) | – | 6 (37.5) | 10 (62.5) | 2 (12.5) | – | – |
4 | – | 2 (12.5) | 10 (62.5) | 7 (43.8) | 4 (25.0) | 8 (50.0) | 6 (37.5) | 4 (25.0) | |
3 | – | – | 6 (37.5) | 3 (18.8) | 2 (12.5) | 4 (25.0) | 3 (18.8) | 4 (25.0) | |
2 | – | – | – | – | – | 2 (12.5) | 3 (18.8) | 4 (25.0) | |
1 | – | – | – | – | – | - | 4 (25.0) | 4 (25.0) | |
Median | 5.0 | 5.0 | 4.0 | 4.0 | 5.0 | 4.0 | 3.0 | 2.5 | |
Noise in the soft tissue | 5 | 1 (6.3) | – | – | – | 2 (12.5) | 2 (12.5) | – | – |
4 | 10 (62.5) | 14 (87.5) | – | – | 6 (37.5) | 2 (12.5) | – | – | |
3 | 5 (31.3) | 2 (12.5) | 7 (43.8) | 9 (56.3) | 8 (50.0) | 10 (62.5) | 2 (12.5) | 2 (12.5) | |
2 | – | – | 5 (31.3) | 4 (25.0) | – | 2 (12.5) | 2 (12.5) | 2 (12.5) | |
1 | – | – | 4 (25.0) | 3 (18.8) | – | – | 12 (75.0) | 12 (75.0) | |
Median | 4.0 | 4.0 | 2.0 | 3.0 | 3.5 | 3.0 | 1.0 | 1.0 | |
Artefacts in the bone | 5 | 16 (100.0) | 16 (100.0) | 16 (100.0) | 15 (93.8) | 13 (81.3) | 12 (75.0) | 13 (81.3) | 12 (75.0) |
4 | – | – | – | 1 (6.3) | 2 (12.5) | 4 (25.0) | 2 (12.5) | 2 (12.5) | |
3 | – | – | – | – | – | – | 1 (6.3) | 2 (12.5) | |
2 | – | – | – | – | – | – | – | – | |
1 | – | – | – | – | – | – | – | – | |
Median | 5.0 | 5.0 | 5.0 | 5.0 | 5.0 | 5.0 | 5.0 | 5.0 | |
Artefacts in the soft tissue | 5 | – | – | – | – | 13 (81.3) | 12 (75.0) | 13 (81.3) | 12 (75.0) |
4 | 15 (93.8) | 12 (75.0) | 15 (93.8) | 7 (43.8) | 2 (12.5) | 3 (18.8) | 2 (12.5) | 2 (12.5) | |
3 | 1 (6.3) | 2 (12.5) | 1 (6.3) | 5 (31.3) | 1 (6.3) | 1 (6.3) | 1 (6.3) | 2 (12.5) | |
2 | – | 2 (12.5) | – | 4 (25.0) | – | – | – | – | |
1 | – | – | – | – | – | – | – | – | |
Median | 4.0 | 4.0 | 4.0 | 3.0 | 5.0 | 5.0 | 5.0 | 5.0 | |