Background: Smoking, which is an important risk factor for periodontitis, induces oxidative stress in the body and causes an imbalance between reactive oxygen species (ROS) and antioxidants, such as superoxide dismutase (SOD). In the present study, the influence of smoking on the periodontium was determined by estimating the levels of SOD in light and heavy smokers with periodontitis.Methods: Seventy subjects in the age range of 20 to 55 years, including 60 smokers and 10 non‐smokers (controls), were selected. Clinical parameters recorded were plaque index (PI), probing depth (PD), and attachment loss (AL). Smokers were divided into light smokers (<10 cigarettes/day) and heavy smokers (≥10 cigarettes/day) and into three subgroups: healthy, mild periodontitis, and moderate periodontitis. Gingival crevicular fluid (GCF) and saliva samples were collected. SOD levels were analyzed using spectrophotometric assay.Results: The mean levels of SOD in the GCF and saliva of smokers were decreased compared to controls. Intra‐ and intergroup analyses showed a significant reduction in the levels of SOD in the GCF and saliva of heavy smokers compared to light smokers and the control group.Conclusions: There was a progressive reduction in SOD levels from healthy non‐smokers to light smokers to heavy smokers. These findings highlight the need to augment the efforts of smoking‐cessation programs. The benefits of reduced smoking and improved antioxidant levels may motivate smoking cessation.

Bio-tribocorrosion is a phenomenon that combines the essentials of tribology (friction, wear, and lubrication) and corrosion with microbiological processes. Lately, it has gained attention in implant dentistry because dental implants are exposed to wear, friction, and biofilm formation in the corrosive oral environment. They may degrade upon exposure to various microbial, biochemical, and electrochemical factors in the oral cavity. The mechanical movement of the implant components produces friction and wear that facilitates the release of metal ions, promoting adverse oro-systemic reactions. This review describes the bio-tribocorrosion of the titanium (Ti) dental implants in the oral cavity and its toxicological implications. The original research related to the bio-tribo or tribocorrosion of the dental implants was searched in electronic databases like Medline (Pubmed), Embase, Scopus, and Web of Science. About 34 studies included in the review showed that factors like the type of Ti, oral biofilm, acidic pH, fluorides, and micromovements during mastication promote bio-tribocorrosion of the Ti dental implants. Among the various grades of Ti, grade V, i.e., Ti6Al4V alloy, is most susceptible to tribocorrosion. Oral pathogens like Streptococcus mutans and Porphyromonas gingivalis produce acids and lipopolysaccharides (LPS) that cause pitting corrosion and degrade the TiO₂. The low pH and high fluoride concentration in saliva hinder passive film formation and promote metal corrosion. The released metal ions promote inflammatory reactions and bone destruction in the surrounding tissues resulting in peri-implantitis, allergies, and hyper-sensitivity reactions. However, further validation of the role of bio-tribocorrosion on the durability of the Ti dental implants and Ti toxicity is warranted through clinical trials.