Kobiakov Oleksandr, DDS, MSc
1. Research methods
Sample preparation for microscopic research. Drying. Drying was done in a vacuum drying oven for 4 hours.
1.1. Previous fixation of the sample for cutting
The size of the provided sample exceeded the maximum allowable dimensions of the press form for pressing into bakelite for further preparation of the sample for research. Therefore, the sample had to be trimmed. To preserve its integrity, the sample was poured into epoxy resin and kept in a vacuum oven for 30 minutes.
a. Cutting
The sample was cut on a Delta Abrasimet cutting machine (Picture 1.2) manufactured by Buehler (Germany) using a BuehlerMet II Wheels- HRC35-50 abrasive wheel with a cooling liquid supply.
b. Pressing into the cage
For further automatic grinding and polishing, the cut sample was pressed into a bakelite cage. This operation was done on a SimpliMet 1000 automatic press (Picture 1.3) by Buehler (Germany).
c. Grinding
The sample was grinded on an automatic grinding and polishing machine GP beta (Picture 1.4) with a multi-position grinding and polishing gear Vector POWER HEAD with a load of 10 N and a rotation speed of the abrasive disc of up to 120 rpm. During the grinding process, BuehlerMet silicon carbide abrasive papers with grit sizes P120, P320, P600, and P1200 were used in sequence. After grinding, the sample was rinsed and wiped with alcohol.
d. Polishing
The sample was polished on the same grinding and polishing machine (Picture 1.4) using felt and a corundum suspension with a particle size of 50 nm. The rotation speed of the polishing surface did not exceed 100 rpm.
1.2. The electron microscopic researches
The researches were carried out on a scanning electron microscope SEM 106I (Picture 1.5) of Selmi (Ukraine) with an attachment for energy dispersive X-ray microanalysis EDS. The window of the EDS detector is made of beryllium, which does not allow to determine the content of chemical elements with an atomic number lower than that of magnesium (O, N, C. B, H, Li). The resolution of the obtained images reached 200 nm, and the accuracy of chemical composition determination significantly depends on the concentration of the element in the material. Microstructure analysis was carried out using a reflected electron detector (COMPO mode) and in a low controlled vacuum mode (this was necessary to remove the charge from the non-conductive epoxy).
2. Research Results
According to the results of electron microscopic research of the sample, it was found that most of the implant ( Picture 2.1) is in contact only with epoxy resin.
In this case, a strong connection appears at the site of bone ingrowth into the implant relief because of mechanical adhesion to it (Picture 2.2).
The research also revealed a coating (Picture 2.3), the thickness of which is about 2 - 4 microns.
The composition of the bone near the implant (Picture. 2.4) is different from the main mass of bone (in the picture, this part of the bone has a darker shade).
Bone ingrowth along the surface of the implant coating and adhesion to it (Picture 2.5) is very dense.
Based on the results of micro-X-ray spectral analysis, the chemical composition of the implant, coating and bone was compared (Picture 2.6).
3. Other product research
Kobiakov Oleksandr, DDS, MSc
Kobiakov Oleksandr, DDS, MSc
PhD. Kaplun D.V.
Alpha Dent
PhD. Kaplun D.V.