a significant trendp = 0.0233
The OR (95% CI) for periodontitis were 1.09 (0.99–1.19) in working group of 40< and ≥52 and 1.10 (1.01–1.20) in working group of >52 hours per week with a significant trend (p = 0.0233) even after adjusting for age, socioeconomic status, healthy behaviour, chronic disease, and dental care status.