We would advise caution as the act of smoking may adversely impact on both the effectiveness of the Invisalign tooth aligners and their discreet aesthetic appearance. Potential staining and discolouration of the appliance may occur as well as the risk of mis-shaping the bespoke fit of the thermoplastic material via the application of extreme heat present in a lit cigarette. Our orthodontic team will almost always recommend patients to try give up smoking before investing time and money in the Invisalign system.