Periodontal disease represents a significant global health concern with established bidirectional relationships with various systemic conditions. Emerging evidence suggests interconnections between psychological factors, particularly anxiety, and periodontal disease progression. This study reviews the impact of non-surgical periodontal therapy (NSPT) on anxiety levels in patients with stage III/IV periodontitis, with additional consideration of smoking status as a modifying factor. Current evidence demonstrates significantly elevated baseline anxiety levels in periodontitis patients compared to periodontally healthy individuals, with the highest levels observed in smokers with periodontitis. Following NSPT, both smoking and non-smoking periodontitis patients typically exhibit significant reductions in anxiety scores coinciding with improvements in clinical parameters, though the magnitude of anxiety reduction appears greater in non-smokers. Significant associations exist between reductions in clinical attachment loss, probing depth, and anxiety score improvements. These findings suggest that effective periodontal therapy may contribute to psychological well-being, highlighting the importance of integrated approaches to periodontal care that address both biological and psychological dimensions of the disease.