Year Site Gender History of
periodontitis		 Smoking Age
Mean (SD) P-valuea Mean (SD) P-valuea Mean (SD) P-valuea Mean years P-valueb
1 year Mesial 0.6 (0.13) 0.22 0.42 (0.19) 0.009 0.45 (0.38) 0.001 0.32 0.008
Distal 0.07 (0.15) 0.28 0.38 (0.22) 0.022 0.51 (0.42) 0.004 0.28 0.009
2 years Mesial 0.12 (0.15) 0.31 0.44 (0.23) 0.015 0.47 (0.48) 0.001 0.3 0.008
Distal 0.14 (0.16) 0.37 0.41 (0.31) 0.014 0.52 (0.32) 0.007 0.32 0.009
3 years Mesial 0.18(0.25) 0.31 0.4 (0.33) 0.006 0.45 (0.33) 0.012 0.36 0.003
Distal 0.19 (0.36) 0.38 0.38 (0.31) 0.015 0.55 (0.42) 0.013 0.38 0.006
4 years Mesial 0.2 (0.25) 0.41 0.37 (0.35) 0.016 0.5 (0.29) 0.009 0.33 0.005
Distal 0.19 (0.36) 0.35 0.39 (0.41) 0.008 0.51 (0.32) 0.013 0.31 0.002
5 years Mesial 0.21 (0.22) 0.36 0.34 (0.45) 0.002 0.47 (0.39) 0.003 0.34 0.007
Distal 0.22 (0.26) 0.48 0.33 (0.51) 0.003 0.49 (0.42) 0.008 0.35 0.009

aIndependent samples t-test P-values.
bPearson correlation coefficients for age.
SD = standard deviation.