Table 5 Effects of jaw lesions and chemotherapy for progression of ORNJ and the onset time compared with different variables

Overall treatment

0.018^b

 Radiotherapy only

29 (23.4%)

19 (65.5%)

10 (34.5%)

 Radiotherapy and surgery with jaw lesions

58 (46.8%)

24 (41.4%)

34 (58.6%)

 Radiotherapy and surgery without jaw lesions

37 (29.8%)

25 (67.6%)

12 (32.4%)

Surgery involving the jaw

0.133^b

 Paramedian or median mandibular osteotomy

20 (16.1%)

5 (25%)

15 (75.0%)

 Marginal mandibulectomy or maxillectomy

30 (24.2%)

14 (46.7%)

16 (53.3%)

 Segmental mandibulectomy

8 (6.5%)

5 (62.5%)

3 (37.5%)

 Surgery with flap reconstruction

32 (25.8%)

18 (56.2%)

14 (43.8%)

0.011^b

 Surgery without flap reconstruction

26 (21.0%)

6 (23.1%)

20 (76.9%)

Different jaw lesions with flap reconstruction

0.115^b

 Paramedian or median mandibular osteotomy

8 (6.4%)

2 (25%)

6 (75%)

 Marginal mandibulectomy or maxillectomy

16 (12.9%)

11 (68.8%)

5 (31.2%)

 Segmental mandibulectomy

8 (6.4%)

5 (62.5%)

3 (37.5)

Paramedian or median mandibular osteotomy with flap reconstruction

8 (6.4%)

2 (25%)

6 (75%)

1.000^b

Paramedian or median mandibular osteotomy without flap reconstruction

12 (9.8%)

3 (25%)

9 (75%)

Marginal mandibulectomy or maxillectomy with flap reconstruction

16 (12.9%)

11 (68.8%)

5 (31.2%)

0.014^b

Marginal mandibulectomy or maxillectomy without flap reconstruction

14 (11.3%)

3 (21.4%)

11 (78.6%)

Chemoradiotherapy and jaw lesions

 Chemoradiotherapy

46 (37.0%)

17 (37.0%)

29 (63.0%)

0.004^b

 Radiotherapy only

78 (63.0%)

51 (65.4%)

27 (34.6%)

 Chemoradiotherapy with jaw lesions

16 (13.0%)

1 (6.2%)

15 (93.8%)

 < 0.001^b

 Radiotherapy only with jaw lesions

42 (33.9%)

23 (54.8%)

19 (45.2%)

 Chemoradiotherapy without jaw lesions

30 (24.2%)

16 (53.3%)

14 (46.7%)

0.036^b

 Radiotherapy only without jaw lesions

36 (29.0%)

28 (77.8%)

8 (22.2%)

 Chemoradiotherapy with jaw lesions

16 (13.0%)

1 (6.2%)

15 (93.8%)

0.002^b

 Chemoradiotherapy without jaw lesions

30 (24.2%)

16 (53.3%)

14 (46.7%)

 Radiotherapy only with jaw lesions

42 (33.9%)

23 (54.8%)

19 (45.2%)

0.033^b

 Radiotherapy only without jaw lesions

36 (29.0%)

28 (77.8%)

8 (22.2%)

Onset time of ORN, mean years (\(\pm\) SD)

 Surgery with jaw lesions (n = 58)

3.3 (3.8)

0.008^a

 Surgery without jaw lesions (n = 66)

5.7 (5.7)

 Jaw lesions with flap reconstruction (n = 32)

2.9 (3.3)

0.484^a

 Jaw lesions without flap reconstruction (n = 26)

3.6 (4.3)

 Chemoradiotherapy (n = 46)

4.3 (4.2)

0.637^a

 Radiotherapy only (n = 78)

4.8 (5.5)

 Chemoradiotherapy with jaw lesions (n = 16)

2.4 (3.6)

0.331^a

 Radiotherapy only with jaw lesions (n = 42)

3.5 (3.8)

 Chemoradiotherapy without jaw lesions (n = 30)

5.0 (4.3)

0.396^a

 Radiotherapy only without jaw lesions (n = 36)

6.3 (6.7)

 Radiotherapy only with jaw lesions (n = 42)

3.5 (3.8)

0.025^a

 Radiotherapy only without jaw lesions (n = 36)

6.3 (6.7)

 Chemoradiotherapy with jaw lesions (n = 16)

2.4 (3.6)

0.041^a

 Chemoradiotherapy without jaw lesions (n = 30)

5.0 (4.3)

 Nasopharyngeal carcinoma patients (n = 180)

6.8 (4.8)

 < 0.001^a

 Non-nasopharyngeal carcinoma patients (n = 125)

4.5 (5.1)