Table 4 Factors influencing sinus mucosal thickness (< 0.8 mm rate: odds ratio)

Sex

Male: 38.5%

2.00

0.31

Female: 55.6%

Age

< 55 years: 66.7%

3.00

0.10

≥ 55 years: 40.0%

Systemic diseases

+: 33.3%

2.43

0.26

−: 54.8%

Time after tooth extraction

< 6 months: 21.4%

6.93

0.008**

≥ 6 months: 65.4%

Smoking

+: 44.4%

1.33

0.70

−: 51.6%

Reason for tooth extraction

per (+): 42.9%

1.56

0.51

per (−): 53.8%

Residual bone height

> 2.5 mm: 55.1%

2.15

0.28

≥ 2.5 mm: 36.3%

Septa

+: 25.0%

3.39

0.29

−: 52.8%

Nasal division

+: 25.0%

4.64

0.038*

−: 60.7%