RESUMO
@#Dental implants are valuable devices for restoring lost teeth. At this moment, nanotechnology has emerged with several techniques to modify implant surfaces. In addition, some evaluation techniques at the nano level are contributing important information regarding tissue and cell interactions with the implanted material. The purpose of this study was to analyze and compare the bone responses to 3 different types of 4.1-mm-diameter, 10mm-long implant surfaces on a dog femur model: 1) Sand blasted with alumina and Acid etched (SA), 2) Resorbable blast media (RBM), functioning as control groups, and 3) Anode oxidation nano-titana (Anodized TiO2) surface implants as experimental group. For this study, implants were placed in 3 beagle dogs (age, 18 months; weight, 11-14 kg). Their purchase, selection, management, and experimental procedure were carried out according to established conditions by the Department of Laboratory Animal Medicine, Medical Research Center, Medical College of Yonsei University. Nineteen turned screw-shaped implants with 3 different surfaces (4.1mm in diameter, 10mm in length) were made from commercially pure titanium (grade IV). Thirteen implants were placed in each beagle dogs no. 1 and 2 and six implants were placed in the remaining beagle dog. Implants placed in beagle dogs no. 1 and 2 underwent histology analysis, X-ray and CT taking, and analysis of relative bone mineral density with Dataviewer program. While removal torque was measured in the implants placed in beagle no. 3 after a healing period of 4 and 8 weeks. A histological evaluation of the specimens in this study showed that osseointegration was achieved for all control and experimental group after a healing period of 4 and 8 weeks. The following means were obtained for bone-implant contact (BIC) percentage for 4 and 8-week groups, respectively: SA: 85.16%, 38.88%; RBM: 41.62%, 58.87%; and Anodized TiO2: 43.85%, 61.3%. The following means were obtained for bone volume (BV) percentage for 4 and 8-week groups, respectively: SA: 34.48%, 51.55%; RBM: 58.56%, 81.56%; and Anodized TiO2: 47.22%, 63.53%. In this study, 8-week consolidated Anodized TO2 surface implants showed increased removal torque value (RTV) compared to that of the 4-week group. The obtained RTV means were 86.0 and 99.7Ncm, respectively, for 4 and 8-week Anodized TiO2 implants. The present study showed that osseointegration occurred in all investigated types of surface-treated implants. However, the control groups showed slight increase in the BIC and BIV values compared to the experimental groups. Therefore the clinical relevance of the observed results remains to be shown.
