Background: This prospective and controlled histologic study evaluates the impact of smoking on bone-to-implant contact, the bone density in the threaded area, and the bone density outside the threaded area around microimplants with anodized surface retrieved from human jaws.
Methods: A total of 24 subjects (mean age 51.32 + or - 7.5 years) were divided in two groups: smokers (n = 13 subjects) and non-smokers (n = 11 subjects). Each subject received one microimplant with oxidized surface during conventional mandible or maxilla implant surgery. After 8 weeks, the microimplants and the surrounding tissue were removed and prepared for histomorphometric analysis.
Results: Three microimplants placed in smokers showed no osseointegration. The newly formed bone showed early stages of maturation, mainly in the non-smokers. Marginal bone loss, gap, and fibrous tissue were present around implants retrieved from smokers. Histometric evaluation indicated that the mean bone-to-implant contact ranged between 25.97% + or - 9.02% and 40.01% + or - 12.98% for smokers and non-smokers, respectively (P <0.001). Smokers presented 28.17% + or - 10.32% of bone density in the threaded area, whereas non-smokers showed 46.34% + or - 19.12%. The mean of bone density outside the threaded area ranged between 18.76% and 25.11% for smokers and non-smokers, respectively (P >0.05).
Conclusion: The present data obtained in human subjects confirm that smoking has a detrimental effect on early bone tissue response around oxidized implant surfaces.