Association between Smokeless Tobacco Use and Risk of Periodontitis in Asian Countries: A Systematic Review and Meta-Analysis

BACKGROUND: Individual studies conducted in Asian countries have reported higher risk of periodontitis among smokeless tobacco (SLT) users in comparison to non-users. Therefore, a systematic review was conducted to summarize the available evidence on this topic. METHODS: Prominent electronic databases were searched using pre-decided MeSH terms and keywords. Screening of titles and abstracts, full text reading, quality assessment and data extraction was done by two investigators independently. The Newcastle-Ottawa scale was used for risk of bias assessment of eligible studies. Meta-analysis was performed for four periodontal outcomes (periodontal pocket depth, loss of attachment, clinical attachment level and gingival recession). A sensitivity analysis was also performed. RESULTS: Of the 546 citations, 367 were screened for eligibility. Finally, 89 studies were shortlisted for full text reading, of which, 36 were found eligible for qualitative analysis. Most of the studies were conducted in India (n=22), were of cross-sectional design (n=33), utilized purposive sampling and 24 studies were included for meta-analysis (n=28) and done on hospital-based population (n=26). Only 13 (37.1%) studies achieved a score of more than 50% (5/10 stars) on quality assessment scale. SLT users had higher odds of greater periodontal pocket depth greater than 4 mm (OR=3.64), gingival recession (OR=1.71) and loss of attachment 4-5 mm (OR=2.83) and mean difference of 1.7 mm for Clinical Attachment Level compared to non-users. CONCLUSION: The studies included in this review suggests that SLT users have poorer periodontal health in comparison to non-users. But most of this evidence comes from cross-sectional studies. Longitudinal studies with rigorous methodology are required to support this elucidation. REGISTRATION: This systematic review protocol has been registered in PROSPERO (CRD42019122964).