Bone Density Around Titanium Implants May Benefit from Smoking Cessation: A Histologic Study in Rats

Purpose: This study tested the hypothesis that interruption of cigarette smoke inhalation (CSI) would reverse its impact on bone quality around implants. Materials and Methods: Sixty-nine rats were assigned to 1 of 4 groups. Group 1 (n = 16) was the control group; group 2 experienced CSI for the duration of the study (150 days); group 3 experienced CSI for 83 days prior to implant placement, until 7 days prior to implant placement, when CSI ceased; and for group 4, CSI exposure was temporarily halted from 7 days before implantation to 21 days afterward. Bone density (the proportion of mineralized bone in a 500-µm-wide zone lateral to the implant) was calculated for each specimen (mean ± SD). Results: In the cortical bone, a slight difference in bone density was noted between the groups (97.66% ± 3.69% for group 1, 98.30% ± 0.95% for group 2, 98.83% ± 0.73% for group 3, and 98.11% ± 1.14 for group 4; P > .05). In contrast, continuous exposure to cigarette smoke (group 2) significantly decreased density in the cancellous bone in comparison to the other groups (25.69% ± 9.41% for group 1, 18.08% ± 6.0% for group 2, 25.46% ± 5.42 for group 3, and 26.20% ± 6.77% for group 4; P .05), with no significant differences between groups 1, 3, and 4 (P > .05). Discussion: The results support the concept that the effects of cigarette consumption on dental implants may be reversible, and therefore suggest that smokers may realize satisfactory outcomes if they cease smoking, even temporarily. Conclusion: In conclusion, smoking may affect bone quality around titanium implants in cancellous bone, and cessation could result in a return toward to the levels of the control group. Keywords: dental implants, osseointegration, smoking, smoking cessation