# Periodontal Health Parameters in Adults: The Role of the Vestibular Fornix Depth
## 3 Results  
The analysis concerned all 100 participants (36 males and 64 females; median age 25 years, IQR 22-27). Inter-rater reliability was very good for the keratinized gingiva (ICC 0.92, 95% CI 0.88 to 0.94), fornix (ICC 0.93, 95% CI 0.90 to 0.95), and phenotype (Cohen's Kappa 0.99, 95% CI 0.99 to 0.99), while it was moderate for the PPD (Cohen's Kappa 0.60, 95% CI 0.44 to 0.77). S Sixty-nine participants (69%) had previously had orthodontic treatments; 18 participants (18%) were smokers (<10 cigarettes/day); and 16/64 females (25%) used oral contraceptives. Overall, the PI was 0.00% (IQR 0.00-1.40%), and the median BOP was 1.39% (IQR 0.00-2.78%). The gum phenotype was thick in 42 participants (42%), and thin in 58 (58%). The median BOP was 1.39% (IQR 0.00-2.78%) in males, and 1.39% (0.00-2.78%) in females (\(p\) = 0.68). The median PI was 0.70% (IQR 0.00-2.78%) in males, and 0.00% (0.00-1.39%) in females (\(p\) = 0.33). The median BOP was 1.39% (IQR 0.00-2.78%) in smokers, and 1.39% (0.00-2.78%) in non-smokers (\(p\) = 0.68). The median PI was 1.39% (IQR 0.00-3.82%) in smokers, and 0.00% (0.00-1.39%) in non-smokers (\(p\) = 0.30). The median BOP was 0.00% (IQR 0.00-2.78%) in females who were using oral contraceptives, and 1.39% (0.00-2.78%) in those who were not (\(p\) = 0.68). The median PI was 0.00% (IQR 0.00-1.39%) in both subgroups of females, regardless of any use of oral contraceptives (\(p\) = 0.94). Mean fornix depth was 10.35 mm (SD 0.66) for the upper dental arch (10.69 mm in males, 10.15 mm in females), and 8.39 mm (SD 0.08) for the lower arch (8.71 mm in males, 8.20 mm in females). Vestibular fornix depth ranged between 3 and 17 mm. The width of keratinized gingiva had a mean of 5.94 mm (SD 0.62) for the upper arch (5.75 mm in males, 6.05 mm in females), and 4.40 mm (SD 0.40) for the lower arch (4.71 mm in males, 4.23 mm in females). The amount of attached gingiva had a mean of 4.50 mm (SD 0.62) for the upper arch (4.30 mm in males, 4.61 mm in females), and 3.20 mm (SD 0.49) for the lower arch (3.45 mm in males, 3.05 mm in females). The amount of attached gingiva ranged between 1 and 10 mm. The proportion of the fornix with attached gingiva had a mean of 43.45% for the upper arch (40.17% in males, 45.39% in females), and 38.12% for the lower arch (39.64% in males, 37.22% in females). The proportion of the fornix with attached gingiva ranged from 31% to 50%, while the proportion of the fornix with keratinized gingiva ranged from 48% to 65% (Table 1). A moderate positive correlation emerged between fornix depth and the width of keratinized gingiva at all sites (for each tooth, for the upper and lower arches, and overall) (Table 1). Figure 5: Measurement of depth of vestibular fornix. Table 2 shows the correlations between the anatomical parameters (fornix depth, width of keratinized gingiva, and attached gingiva) and the periodontal parameters. No statistically significant correlations came to light between the anatomical and periodontal parameters (Table 2). When participants were compared by overall fornix depth \(\geq\)7 vs. \(<\)7 mm, we found a median BOP of 1.39% (IQR 0.00-2.78%) in the former, and 0.00% (0.00-1.39%) in the latter (\(p=0.62\)). The median PI was 0.00% (IQR 0.00-1.40%) in participants with an overall fornix depth \(\geq\)7 mm, and 0.00% (0.00-0.70%) in those with an overall fornix depth \(<\)7 mm (\(p=0.66\)). The thin gum phenotype was associated with a narrower keratinized gingiva (upper arch, \(p=0.0.02\); overall, \(p=0.0.02\)) (Table 3). Participants who had previously had orthodontic treatments seemed to have less keratinized gingiva in the upper arch, and a shallower formix depth in the upper arch, and in the fornix as a whole, than participants who had no history of such treatments, but the difference was only close to statistical significance (Table 4).