Heavy smoking may negatively impact the optimal time for implant placement, according to a recent study. Researchers discovered that heavy smoking slowed the health of posterior mandible implant but did not impact the survival rate of implants.

The results of this study heavily suggest that smoking promoted the loss of marginal bone and the continued development of deep gum pockets.

“These results imply that it might be of importance to select the right time point to apply the implant lading for heavy smokers,” wrote lead researcher Cong Sun in the Journal of Oral Implantology.

The study was conducted by Dr. Sun and researchers at the First Affiliated Hospital of Xi’an Jiaotong.

Impact of Smoking

Earlier studies have suggested that smokers suffer from increased implant failure rates and a higher risk of postoperative infection, as well as greater marginal bone loss. However, additional analysis has suggested that smoking only significantly impacts the survival of implants placed in the maxilla, and some reports indicate that smoking does not dramatically impact the survival of implants placed in the mandible.

“Currently, informative studies on the influence of heavy smoking on single-tooth implants placed at the posterior mandibles of smokers are lacking,” noted the study authors. “However, this information/knowledge is needed for surgeons to make informed decisions and refine treatment plans to optimize outcomes.”

Researchers began to evaluate postsugery bone healing and peri-implant tissue response in heavy smokers who received dental implants due in part to partially edentulous posterior mandibles.

The study involved 16 heavy smokers and 16 nonsmokers. All of the study participants were men between the ages of 25 to 65. Among the participants, 45 dental implants were placed.

Heavy smokers were classified as those who smoked one or more packs of cigarettes per day for at least a decade. Nonsmokers had no history of smoking.

Since the majority of implant failures occur between the second surgery phase and first year of functional loading, researchers examined implant stability during:

• The first 12 weeks after surgery prior to loading
• The first after following loading

Researchers monitored implant stability for the initial three months following implantation. Changes in stability during bone healing before loading represent changes at the implant-bone interface.

In both groups, the stability of the implant decreased from the initial measurement taken following surgery, with the lowest recorded stability rating coming around 14 days after surgery. However, the rate of healing between the participants diverged between two weeks and three months.

Furthermore, examination of samples of jaw marrow from the participants indicated that samples from nonsmokers exhibited a better ability to form calcified nodules and mineralization when compared to samples taken from smokers. A reduced ability to mineralize would slow osseointegration, noted researchers.

Between 6 and 12 months, researchers found that marginal bone loss and probing depth were dramatically higher in smokers when compared to the nonsmokers. This suggested to researchers that after a short loading time, heavy smokers had an increased risk of developing inflammation in the surrounding soft tissue. This inflammation could negatively impact implant success rates.

Impact on Osseointegration

Researchers involved in the study noted that their results differed in some ways from earlier studies that found that smoking had no significant impact on osseointegration or marginal bone loss. The results of the study may have occurred because of the use of different implants or some other unknown factor, admitted researchers.

Researchers also noted the limitation of their study in the small sample size of their participant group and limited duration of examination. For these reason, researchers believe further examination on this topic is warranted.