## 4 Discussion  
According to current studies, the most significant evidence regarding the link between periodontitis and systemic conditions encompasses the biunivocal relationship between periodontal inflammation and DM [21; 22]. Periodontitis consists of a plaque-induced inflammation of the periodontium. The pathogenic importance of periodontal inflammation in T2 DM has been extensively demonstrated, whereas the link between T1 DM and periodontitis has not been extensively investigated. Paraprobiotics are non-viable microorganisms that may provide benefits to the host thanks to their anti-inflammatory, immunomododulatory, anti-proliferative, antioxidant, and antimicrobial activity. Even the influence of paraprobiotics on patients with T1 DM represents an unexplored field. Accordingly, the objective of the present report was to compare the effect of two domiciliary oral hygiene protocols (the experimental one based on paraprobiotics) on the periodontal clinical status as well as on the amount of glycosylated hemoglobin (HbA1c) in patients affected by type 1 diabetes mellitus. The first null hypothesis of the study has been rejected. In fact, significant differences were found for the clinical periodontal parameters considered in the study. In particular, PPD significantly decreased from baseline to the subsequent 3 months, with no further significant reductions at 6 months. No significant intergroup differences have been assessed comparing the control and trial group. Additionally, the same intergroup and intragroup differences have been found for PI. Therefore, both the use of probiotics-based toothpaste and mouthwash, as well as the use of a natural extracts-based toothpaste, resulted in a \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Group** & **Time** & **Mean** & **St Dev** & **Min** & **Median** & **Max** & **Significance \({}^{*}\)** \\ \hline Control Group & T0 & 3.62 & 1.69 & 1.00 & 4.00 & 8.00 & A, C \\  & T1 & 3.42 & 1.67 & 1.00 & 3.00 & 8.00 & B, D \\  & T2 & 3.30 & 1.67 & 1.00 & 3.00 & 8.00 & B \\ Trial Group & T0 & 4.07 & 1.23 & 2.00 & 4.00 & 7.00 & A, D \\  & T1 & 3.52 & 1.02 & 2.00 & 3.00 & 8.00 & B, C \\  & T2 & 3.43 & 1.06 & 2.00 & 3.00 & 8.00 & B, C \\ \hline \hline \end{tabular}  
* Means with same letters do no show statistically significant differences (\(p\) > 0.05).  
\end{table} 
Table 7: Descriptive statistics of PPD measurements. Figure 6: PPD values among the time frames of the study. \({}^{*}\) = \(p\) < 0.05. ns = not significant. similar improvement of PPD and PI, as expected, with a reduction in the pathological values starting from the first endpoint. Conversely, CAL significantly decreased in both groups only after 6 months from the baseline, with no significant intergroup differences even in this case. The different pattern of variation of CAL, if compared to PPD and PI, could be explained by the fact that the reconstitution of the attachment level requires a longer time to occur. Finally, as regards BoP, a significant progressive reduction occurred at every endpoint starting from the baseline in the trial group, whereas in the group treated with the natural extracts-toothgate the reduction at 3 months from the baseline was more significant, and no further significant reductions were assessed at 6 months. On the basis of these considerations, both the combination of the probiotics-based toothpaste and mouthwash and the use of the natural extracts-based toothpaste similarly led to an improvement of PPD, PI, and CAL. Probiotics are defined as \"live microorganisms which when administered in adequate amounts confer a health benefit on the host\" (FAO/WHO) [23].