The impact of nicotine on osseointegration - An experimental study in the femur and tibia of rabbits

Objectives: The aim of the present study was to analyze the effect of an enhanced systematic dose of nicotine on osseointegration of titanium implants. Material and methods: Sixteen female rabbits received either nicotine ( n = 8) or saline ( n 8) administered subcutaneously via mini-osmotic pumps for 2 months. The pump delivered 6 mg/kg/min of nicotine for the animals in the test group. Blood was withdrawn and plasma cotinine levels were measured weekly. Thirty-two titanium implants were inserted into the femur and tibia of all rabbits after 4 weeks and after 6 weeks of nicotine/ placebo exposure. Thus, 2- and 4-week healing groups were created. Biomechanical evaluation by (i) resonance frequency analysis test (RFA) on all implants after insertion and before sacrifice and (ii) removal torque test (RMT) on tibial implants before sacrifice was performed. All implants placed in the femur were processed to undecalcified ground sections. The percentage of bone-to-implant contact (BIC) and of bone area within the threads (BD-i) were measured. Results: No significant difference in RMT and RFA values was found between the test and the control group. Histomorphometric measurements of the BIC and the peri-implant BD-i showed no significant differences between the test and the control group after 2 or after 4 weeks. Conclusion: Nicotine exposure for a short period of time even in a high dose did not have a significant impact on implant osseointegration in rabbits

The impact of nicotine on bone healing and osseointegration - An experimental study in rabbits

Objecives: To examine the short-term effect of nicotine on bone healing and osseointegration. Material and methods: Sixteen female rabbits were divided into two groups. The test group was exposed to nicotine tartrate for 8 weeks and the control group was exposed to placebo. Nicotine or placebo was administered via a miniosmotic pump and plasma cotinine levels were measured weekly. The pump delivered 15 mg of nicotine/day for the animals in the test group. All rabbits had three tibial bone preparations. In the proximal and distal bone bed, implants were placed after 4 weeks (right tibia) and after 6 weeks (left tibia). Thus, 2- and 4-week healing groups were created. Removal torque test (RMT) was performed at the distal implants. Ground sections were made from the proximal and the central bone beds. The fraction of mineralized bone in contact to the implant (BIC) and the bone density within the implant threads (BD-i) were determined for the bone-implant specimens. For the central bone beds without implants the bone density (BD-c) in the bone defects was determined. Results: No significant difference in RMT values was found between the test and the control group. Histomorphometric measurements of the BIC and the peri-implant BD-i showed no significant differences between the test and the control group after 2 or 4 weeks. Significant differences were, however, found between the 2- and 4-week samples. In the central bone beds, there was no significant difference in BD-c between the test and the control group. Conclusion: Nicotine exposure in a short period of time did not have a significant impact on bone healing or implant osseointegration in rabbits