Histopathological morphometric evaluation of 2 different hydroxyapatite-bone derivatives in sinus augmentation procedures: A comparative study in humans
Z. Artzi et al., Histopathological morphometric evaluation of 2 different hydroxyapatite-bone derivatives in sinus augmentation procedures: A comparative study in humans, J PERIODONT, 72(7), 2001, pp. 911-920
Background: Xenografts to augment the maxillary sinus have been used extens
ively. The aim of the present study was to evaluate, qualitatively and quan
titatively, two different HA derivatives of natural and synthetic sources o
n newly formed bone in the augmented sinus.
Methods: A bilateral sinus augmentation procedure with simultaneous (16 out
of 20 sites) or subsequent implant placement was performed in 10 patients.
The antrum was randomly filled with a deproteinized, bovine hydroxyapatite
mineral (B-HA) on one side and a non-ceramic resorbable hydroxyapatite (NC
-HA) on the other. Cylindrical specimens were harvested from the augmented
core at 12 months. Decalcified specimens were sectioned at a cross-horizont
al plane and stained with hernatoxylin and eosin for histopathologic and hi
stomorphometric examinations. Tissue area fractions of bone, marrow, and th
e grafted particles were calculated for each specimen from the lateral to t
he deep region, and changes in values were compared within each material an
d between them.
Results: New bone formation was evident. B-HA and NC-HA particles were obse
rved in all specimens surrounded by newly formed bone in direct connection
or by soft tissue marrow. Morphometrically in the B-HA sites, from the late
ral to deeper area, bone area fraction increased from 29.8% to 54.2% (avera
ge 42.1 %) and marrow area fraction decreased from 37.9% to 26.7% (average
33.3%). The mineral area fraction decreased from 32.3% to 19.1% (average 24
.7%). All increasing/decreasing patterns were statistically significant (P
<0.001). In the NC-HA sites, from the lateral to deeper area, bone area fra
ction increased from 25% to 36.5% (average 32.3%) and marrow area fraction
decreased from 51.6% to 41.9% (average 43.2%) (P <0.001). The mineral area
fraction decreased from 29% to 21.7% (average 24.6%) (P = 0.038). Compariso
n between the two HA derivative groups showed a significant difference betw
een the bone area fraction averages (P= 0.0053) and between the increasing
patterns along the core depth (P= 0.0006). There was also a significant dif
ference between the decreasing marrow patterns (P= 0.003), but not between
their averages. Comparison between the mineral area fractions showed no dif
ferences.
Conclusions: B-HA and NC-HA were proven to be biocompatible materials. Alth
ough the B-HA-augmented sites showed a higher percentage of bone formation
at 12 months, both are suitable bone derivatives in sinus augmentation proc
edures and can accommodate osseointegrated implants.