Table 1.
Univariate analysis of risk factors of osteoradionecrosis
| Factors | Subgroup | n | p value | 5-y ORN rate (%) |
|---|---|---|---|---|
| V10 |
<14.5 ml |
31 |
|
26.1 |
| |
≥14.5 ml |
32 |
0.015 |
53 |
| V20 |
<11.9 ml |
31 |
|
20 |
| |
≥11.9 ml |
32 |
0.001 |
58.5 |
| V30 |
<8.1 ml |
31 |
|
13.7 |
| |
≥8.1 ml |
32 |
0.001 |
64.4 |
| V40 |
<4.6 ml |
31 |
|
12.1 |
| |
≥4.6 ml |
32 |
0.0002 |
67.7 |
| V50 |
<3.0 ml |
31 |
|
11.7 |
| |
≥3.0 ml |
32 |
0.0002 |
69.5 |
| Age (years) |
<59 |
31 |
|
33.5 |
| |
≥59 |
32 |
0.23 |
45.5 |
| Sex |
Male |
31 |
|
40.4 |
| |
Female |
32 |
0.5 |
38.2 |
| Teeth in the PTV |
None |
34 |
|
5.9 |
| |
Some |
29 |
0.0001 |
81 |
| Smoking |
Yes |
22 |
|
41.6 |
| |
No |
41 |
0.66 |
38.6 |
| Alcohol |
Yes |
31 |
|
48.6 |
| |
No |
32 |
0.11 |
30.3 |
| Chemotherapy |
Yes |
23 |
|
54.0 |
| No | 40 | 0.04 | 30.5 |
A large V10 to V50 and the presence of teeth within the PTV were found to correlate with ORN development.