Bone Density Around Titanium Implants May Be Influenced by Intermittent Cigarette Smoke Inhalatio

Purpose: This study investigated the influence of cigarette smoke on bone healing around titanium implants placed in rats. Materials and Methods: After administration of anesthesia, the tibia surface was exposed and screw-shaped titanium implants (4.0 mm in length and 2.2 mm in diameter) were placed bilaterally (1 each side). The animals (n = 32) were randomly assigned to either group 1 (control, n = 18) or group 2 (intermittent cigarette smoke inhalation, n = 14). After 60 days, the animals were sacrificed and undecalcified sections obtained. Bone density (the proportion of mineralized bone in a 500-µm-wide zone lateral to the implant) was measured in the cortical (zone A) and cancellous bone (zone B) areas. Results: In zone A, a slight difference in bone density was noted between the groups (96.18% ± 1.08% and 95.38 ± 1.17% in groups 1 and 2, respectively; P > .05) but was not statistically significant. In contrast, bone density was significantly decreased in zone B in the animals that were exposed to cigarette smoke (17.57 ± 6.45% and 11.30 ± 6.81% for groups 1 and 2, respectively; P .05). Discussion: Whether different results would be observed if animals were exposed to cigarette smoke for a longer period of time and/or before implant placement remains to be investigated. Conclusion: Although intermittent cigarette smoke exposure may not seriously affect cortical bone density, it may jeopardize bone quality around titanium implants in the cancellous bone area.