The effect of cigarette smoking on early osseointegration of dental implants: a prospective controlled study

Objective: This study evaluated the effect of cigarette smoking on the percentage of early bone-to-implant contact (BIC%), the bone density in the threaded area (BA%) as well as the bone density outside the threaded area (BD%) around micro-implants with sandblasted acid-etched surface retrieved from human jaws. Material and methods: Twenty-two subjects (mean age 55.4 +/- 4.5 years) were divided in two groups: smokers (n = 11 subjects) and never-smokers (n = 11 subjects). Each subject received one micro-implant during conventional mandible or maxilla implant surgery. After 8 weeks, the micro-implants and the surrounding tissue were removed and prepared for histomorphometric analysis. Results: Two micro-implants placed in smokers showed no osseointegration. Early stages of maturation of the newly formed bone were present, mainly in the never-smokers. Marginal bone loss, gap, and fibrous tissue were present around some implants retrieved from smokers. Histometric evaluation indicated that the mean BIC% ranged between 25.9 +/- 9.1 and 39.8 +/- 14.2 for smokers and non-smokers, respectively (P = 0.02). Smokers presented 28.6 +/- 10.1 of BA% while never-smokers showed 46.4 +/- 18.8 (P = 0.04). The mean of BD% ranged between 19.1 +/- 7.6 and 28.5 +/- 18.8 for smokers and never-smokers, respectively (P = 0.21). Conclusion: Cigarette smoking has a detrimental effect on early bone tissue response around sandblasted acid-etched implant surface topographies.