Search

ObjectivesTo measure the lateral surface area of microgrooved zirconia implants, to evaluate the cell geometry and cell density of human fetal osteoblasts seeded on zirconia microgrooved implants, to describe the surface roughness and chemistry, and to evaluate the activity of human fetal osteoblasts seeded on zirconia microgrooved disks. Materials and methodsThis experimental in vitro study used 62 zirconia implants and 130 zirconia disks. Two experimental groups were created for the implants: 31 non-microgrooved implants (Control) and 31 microgrooved implants (Test); two experimental groups were created for the disks: 65 non-microgrooved disks (Control) and 65 microgrooved disks (Test). The following evaluations of the implants were made: lateral surface area (LSA), cell morphology, and density of human fetal osteoblasts seeded on implant surfaces. On the disks, surface parameters (roughness and chemistry) and cell activity (alkaline phosphatase - ALP and alizarin red - ALZ) were evaluated at 7 and 15days. ResultsLSA was lower for control implants (62.8mm) compared with test implants (128.74mm) (P lt 0.05). Cell bodies on control surfaces were flattened and disorganized, while in the test group, they were aligned inside the microgrooves. Control group cells showed few lamellipodia, which were attached mainly inside topographical accidents (surface cracks, valleys, and pits). Test group implants presented cells rich in lamellipodia prolongations, attached to the inner walls or to the borders of the microgrooves and in the flat areas between the microgrooves. Cell density was higher in the test group compared with controls (P lt 0.05) Surface roughness and oxygen content increased in test disks samples compared with controls (P lt 0.05). Carbon and aluminum were reduced in disks test samples compared with controls (P lt 0.05), and ALP and ALZ levels were significantly increased on test surfaces (P lt 0.05) at both study times. ConclusionsWithin the limitations of th

PurposeThe study aims to assess the total soft tissue (ST) width, crestal bone level (CBL), bone-to-implant contact (BIC), and bone density (BD) for zirconia implants textured with microgrooved surfaces and immediately loaded. Materials and MethodsThis study included 51 implants; one implant from each study group was retained for surface characterization. The 48 remaining implants were inserted randomly in premolar areas of both sides of the healed edentulous lower jaws of foxhound dogs. They were divided into three groups of 16: control (titanium); test A (zirconia), and test B (microgrooved zirconia). The implants were splinted and covered with an acrylic bridge. A split-mouth design was used and immediate occlusal loading was applied on one side, while the other side did not have occlusal contact. ST, CBL, BIC, and BD were evaluated after 3 months. The effects of immediate loading on these parameters were analyzed. ResultsAll the implants were osseointegrated. ST was established at 3 months with mean values of 2.90.4mm for all groups. No differences were appreciated between loaded and unloaded sides regarding ST (p>.05). CBL showed a mean of 1.2 +/- 0.3mm for all groups without differences between loaded and unloaded sides (p>.05). BIC percentages were significantly higher for loaded all-microgrooved implants (p<.05). BD percentages were higher in areas close to all-microgrooved implants (p<.05) and significantly higher for loaded implants than unloaded. ConclusionsWithin the limitations of the present study, it may be concluded that for zirconia dental implants with microgrooved surfaces and immediate loading, the thickness of STs remains stable resulting in 3mm mean biologic width, that crestal bone preservation is related to insertion depth, and that higher BIC percentages and increased BD around implants microgrooved over the entire intraosseous area may be expected at 3 months following implant insertion and immediate loading.