# Periodontal Health Parameters in Adults: The Role of the Vestibular Fornix Depth
## 4 Discussion  
This study investigated periodontal parameters in relation to the depth of the vestibular fornix in individuals in good periodontal health. Our data showed that the anatomical parameters, such as the depth of the fornix, the width of the keratinized gingival, and the width of the attached gingival have absolute values better represented on a level with the upper arch than on the lower one. This observation was also made in the study by [PERSON] et al., who identified the same difference between the two regions [4]. Our data indicated that the depth of the vestibular fornix could vary considerably from one individual to another, and from one part of the oral cavity to another. In the upper arch, the minimum fornix depths were much the same between pairs of contralateral teeth and amounted to 5 mm in the region of the central incisors, 7 mm on a level with the lateral incisors, and 5 mm in the region of the canine teeth. In the lower arch, they were 3 mm, 4 mm, and 3 mm, respectively. In all regions of the oral cavity, there was at least 1 mm of attached gingiva--a finding consistent with the reports from [PERSON] et al. and [PERSON], who demonstrated that 1 mm of attached gingiva sufficed for an adequate periodontal health [3; 12]. The width of attached gingiva in our sample had a mean 4.5 mm (min 1.0 mm, max 10.0 mm) for the upper arch, and 3.2 mm (min 1.0 mm max 9.0 mm) for the lower arch. This wide range of values is in accordance with the wide anatomical variability of the healthy periodontitis and is in agreement with previous anatomical studies [1; 13]. These values also corroborate [PERSON]'s findings for the attached gingiva (min 1.0 mm, max 7.0 mm): [PERSON] considered only the lower jaw and found the attached gingiva narrowest on a level with the canines [3]. The percentage of the fornix with keratinized gingiva was relatively similar from canine to canine, with a mean of 54% in the lower arch and 58% in the upper arch. For both dental arches, the percentage of the fornix occupied by keratinized gingiva tended to \begin{table}
\begin{tabular}{l c c c} \hline  & **Participants with No History** & **Participants Who Had** & \\  & **of Orthodontic Treatments:** & **Previously Had Orthodontic** & _p-Value_ \\  & **Mean (SD)** & ** Treatments: Mean (SD)** & _p-Value_ \\ \hline Keratinized gingiva (upper arch), mm & 6.4 (1.5) & 5.7 (1.4) & 0.08 \\ \hline Keratinized gingiva (lower arch), mm & 4.7 (1.49 & 4.3 (1.0) & 0.13 \\ \hline Keratinized gingiva (overall), mm & 5.5 (1.3) & 5.0 (1.1) & 0.09 \\ \hline Fornix depth (upper arch), mm & 10.9 (1.9) & 10.1 (1.8) & 0.08 \\ \hline Fornix depth (lower arch), mm & 8.9 (2.1) & 8.1 (1.8) & 0.10 \\ \hline Fornix depth (overall), mm & 9.9 (1.8) & 9.1 (1.5) & 0.08 \\ \hline \end{tabular}
\end{table} 
Table 4: Associations between anatomical parameters and orthodontic treatments. \begin{table}
\begin{tabular}{l c c c} \hline  & **Thick Gum Phenotype** & **Thin Gum Phenotype** & _p-Value_ \\ \hline  & Mean (SD) & Mean (SD) & \\ Keratinized gingiva (upper arch), mm & 6.4 (1.4) & 5.6 (1.4) & 0.02 \\ Keratinized gingiva (lower arch), mm & 4.7 (1.2) & 4.2 (1.1) & 0.06 \\ Keratinized gingiva (overall), mm & 5.6 (1.2) & 4.9 (1.1) & 0.02 \\ Fornix depth (upper arch), mm & 10.8 (1.8) & 10.0 (1.9) & 0.06 \\ Fornix depth (lower arch), mm & 8.5 (1.9) & 8.3 (1.9) & 0.58 \\ Fornix depth (overall), mm & 9.7 (1.6) & 9.1 (1.7) & 0.19 \\ \hline  & Median (IQR) & Median (IQR) & \\ BOP & 1.39 (0.00–2.78) & 0.00 (0.00–2.78) & 0.24 \\ PI & 0.00 (0.00–2.78) & 0.00 (0.00–1.39) & 0.43 \\  & \(n\) (\%) & \(n\) (\%) & \\ Males & 15 (36) & 21 (36) & 0.99 \\ \hline \end{tabular}
\end{table} 
Table 3: Associations between clinically relevant parameters and gum phenotype. diminish from the central incisors to the canine. As for the lower arch, these findings on the relationship between gingiva and the fornix again confirm the findings of [PERSON] [3]. There was evidence of a positive correlation between fornix depth and the width of keratinized gingiva.