Please activate JavaScript!
Please install Adobe Flash Player, click here for download
ePaper created 2017-01-11, 10:22:38 | version 1.38.0
Journal of Oral Science & Rehabilitation Volume 2 | Issue 4/2016 35 I m p l a n t s u r f a c e s a n d b l a s t e d w i t h t i t a n i u m d i o x i d e m i c r o p a r t i c l e s Figs. 3 & 4 Itapiranga Faculty of Veterinary Medicine, Itapi- ranga, Brazil. The rabbits were anesthetized by intramuscular ketamine (35 mg/kg; Agener Pharmaceutica, Brazil). Thereafter, a muscle re- laxant (Rompum 5 mg/kg, Bayer, Brazil) and a tranquilizer (Acepran 0.75 mg/kg, Univet, Brazil) were injected intramuscularly.Additionally, 1 mL of local anesthetic (3% prilocaine-felypressin, Astra, Mexico) was injected subcutaneously at the site ofsurgeryto improve analgesia and con- trolbleeding.Askinincisionwithaperiostealflap wasusedtoexposetheboneintheproximaltibia. The preparation of the bone site was done with bursundercopioussalineirrigation.Twoimplants were inserted into the tibial metaphysis of each rabbit (Fig. 3), one most proximal at 5 mm from thearticulationandtheother10mmtothedistal, thus avoiding differences in bonetypologyinthis area. The implant position was randomized for each animal at www.randomization.com. The tibia was chosen as the implant site because it provides easier surgical access. The implant in- sertion was performed by hand with a torque of < 20 N until locking of the implant in the oppo- site cortical portion of the osteotomy, as part of the implant shoulder just out in relation to the top of the cortical bone crest, thereby avoiding excessivecompressionoftheboneduetoimplant design. The periosteum and fascia were sutured with catgut and the skin with silk. Postoperati- vely, a single dose of 600,000 IU of benzathine penicillin (Benzetacil, Eurofarma Laboratórios, Rio de Janeiro, Brazil) was used. After surgery, the animals were placed in individual cages with 12-h cycles of light, controlled temperature (21 °C), and food and water ad libitum. No com- plications or deaths occurred in the postoperati- ve period. All of the animals were euthanized after four weeks using an intravenous overdose of ketamine (2 mL) and xylazine (1 mL). Atotal of 24 implants were retrieved. The implants of all right tibiae were immediately analyzed using a torque-testing machine (CME,Técnica Industrial Oswaldo Filizola, Guarulhos, Brazil), which was fully controlled by DynaView Torque Standard/ Pro M software (Fig. 4). Allofthe implants ofthe lefttibiaewere used for histological analysis and were placed in 10% formalinafterremovalandtakentotheBiotecnos Laboratory (Santa Maria, Brazil).Afterthe fixati- on period,theywere dehydrated in an ascending series of alcohols and embedded in glycol met- hacrylate resin (Technovit 9100 VLC, Kulzer, Hanau, Germany) to produce undecalcified sec- tions.Undecalcifiedcutandgroundsectionsthat contained the central part of each implant and had a final thickness of 15 μm were produced usingamacro-cuttingand-grindingsystem(Iso- met 2000, Buehler, Braunschweig, Germany). The sections were stained with picro-sirius- hematoxylin, and histomorphometric analysis was then carried out. The specimens prepared for the analysis of the tissue around the implant were examined under a light microscope (EOS 200, Nikon, Tokyo, Japan). After digitizing the phase of each specimen under a light microsco- pe, the percentage of bone-to-implant contact (BIC%)was measured usingthe ImageToolsoft- ware for Microsoft Windows (Version 5.02). BIC% was calculated as the percentage of the total length of bone in direct contact with the implant surface, from the first crestal bone con- tact to the most apical contact. The statistical analysis was performed using the t-test for comparison between groups. Two correlation measurements were used to assess the relationship between the groups: Pearson’s correlation coefficient (with -1 < R < 1; when R is Fig. 3 Image of the implants inserted into the tibia. Fig. 4 Image of the computerized torque machine used in the removal torque test. Volume 2 | Issue 4/201635