Standardised radiographs taken before (T1) and 12 months after surgery (T2),
digitised and displayed in pseudo-color.
Mean ratios in pseudocolors for before surgery (T1) / recall (T2)
digitised radiographs. Green, yellow and red areas indicate density gains.
Areas without change are blue. Density loss is shown in dark blue and violet.
However, the clinical crowns of the two premolars were at the maximum
range of saturation, giving an erroneous image of some loss of density.
The recording conditions were adjusted so that the ideal values were
at the sites of pertinent information: the bone areas that were
grafted or controls.
Three Sites Of Interest (SOI) are defined:
SOI 1 is the grafted osseous defect,
SOI 2 is located beneath the graft,
and SOI 3 is the control site.
Density scale. From 0 (violet) to 255 (red).
Table I
|
|
Sites |
Of (SOI)
|
Interest |
|
|
SOI 1
|
SOI 2
|
SOI 3
|
|
Max.
|
1.66 |
1.09 |
1.25 |
Ratio values (T12m / T0) |
Mean
|
1.35 |
0.89 |
0.91 |
|
Mini.
|
1 |
0.77 |
0.68 |
SOI 1 was the grafted osseous defect. Visual examination showed increasing density from the periphery to the centre of the defect. The DIR ratios ranged from 1 to 1.66, with a mean of 1.35. Since a value of 1 indicates sites without any change, 1.35 indicated a 35% gain in bone density, or bone mass in the SOI. The value 1.66 was the density in the centre of the grafted site (Table 1). SOI 2 was located immediately beneath the graft, and showed a slight loss of density. The ratios ranged from 0.77 to 1.09 (mean value 0.89). This means an 11% loss of bone mass (bone density), with extremes of 23% loss and 9% gain. SOI 3 was a control site that included superficial and deep areas of bone.
|