Background/Aim. The function of dental implants depends on their stability in
bone tissue over extended period of time, i.e. on osseointegration. The
process through which osseointegration is achieved depends on several
factors, surgical insertion method being one of them. The aim of this study
was to histopathologically compare the impact of the surgical method of
implant insertion on the peri-implant bone tissue. Methods. The experiment
was performed on 9 dogs. Eight weeks following the extraction of lower
premolars implants were inserted using the one-stage method on the right
mandibular side and two-stage method on the left side. Three months after
implantation the animals were sacrificed. Three distinct regions of bone
tissue were histopathologically analyzed, the results were scored and
compared. Results. In the specimens of one-stage implants increased amount of
collagen fibers was found in 5 specimens where tissue necrosis was also
observed. Only moderate osteoblastic activity was found in 3 sections. The
analysis of bone-to-implant contact region revealed statistically
significantly better results regarding the amount of collagen tissue fibers
for the implants inserted in the two-stage method (Wa = 59 < 66,5, ? = 0.05),
but necrosis was found in all specimens, and no osteoblastic activity.
Histopathological analysis of bone-implant interface of one-stage implants
revealed increased amount of collagen fibers in all specimens, moderate
osteoblastic activity and neovascularization in 2 specimens. No inflammation
was observed. The analysis of two-stage implants revealed a marked increase
of collagen fibers in 5 specimens, inflammation and bone necrosis were found
in only one specimen. There were no statistically significant differences
between the two methods regarding bone-implant interface region.
Histopathological analysis of bone tissue adjacent to the one-stage implant
revealed moderate increase of collagen tissue in only 1 specimen, moderate
increase of osteoblasts and osteocytes in 3 specimens. No necrotic tissue was
found. The analyzed specimens of bone adjacent to two-stage implants revealed
a moderate increase in the number of osteocytes in 3 and a marked increase in
6 specimens respectively. This difference was statistically significant (Wb =
106.5 > 105, ? = 0.05). No necrosis and osteoblastic activity were observed.
Conclusion. Better results were achieved by the two-stage method in
bone-to-implant contact region regarding the amount of collagen tissue, while
the results were identical regarding the osteoblastic activity and bone
tissue necrosis. There was no difference between the methods in the
bone-implant interface region. In the bone tissue adjacent to the implant the
results were identical regarding the amount of collagen tissue, osteoblastic
reaction and bone tissue necrosis, while better results were achieved by the
two-stage method regarding the number of osteocytes.