Oral Complications Associated with Habitual Khat Chewing: A Systematic Review

Objective: Habitual khat chewing is prevalent in East Africa and the Arabian Peninsula, but its long-term effects on oral health remain poorly defined. This review systematically evaluates the oral health complications associated with khat chewing, including periodontal disease, mucosal lesions, dental caries, tooth wear, tooth loss, and temporomandibular disorders (TMD). Methods: A systematic review of PubMed, Scopus, Web of Science, and Google Scholar was conducted for English-language studies published up to August 2024. Observational and interventional studies assessing oral outcomes in khat chewers were included. Screening and data extraction were performed independently by two reviewers. Quality assessment was conducted using National Institute of Health tools. A qualitative synthesis was performed due to high heterogeneity. Results: Fifty-seven studies were included. Khat chewing was associated with periodontal disease (gingival recession, clinical attachment loss), mucosal white lesions, tooth wear, and increased risk of TMD. A few studies reported reductions in plaque and gingival indices, but these benefits were inconsistent and outweighed by harmful effects. Variability in diagnostic criteria and study design limited causal inference. Conclusion: Khat chewing adversely affects oral health, with strong evidence for periodontal and mucosal damage. Preventive public health strategies and longitudinal studies are needed to mitigate these risks.