# Ozonized Water Administration in Peri-Implant Mucositis Sites: A Randomized Clinical Trial
## 4 Discussion  
The assurance of correct oral hygiene procedures plays a key role for the long-term maintenance of implant sites, thus avoiding the development of peri-implant mucositis and eventually peri-implantitis, with the risk of implant failure. Several hygiene protocols have been proposed, all sharing the common goal of disrupting the subgingival biofilm while avoiding the alteration of the implant surface [25]; these treatment modalities include mechanical debridement [26], the administration of chlororexidine [27], and air polishing with glycine or bicarbonate powder [28]. Despite this quite wide range of therapeutic modalities, until now, none seemed to meet all the requirements which include the cleaning efficacy, the biocompatibility, and a low risk of alterations of the implant's surface. Based on this consideration, the aim of the present report has been that of evaluating the efficacy of ozone therapy for the treatment of peri-implant mucositis. Several clinical conditions are currently being addressed by means of ozone, due to its recognized wide  
Figure 5: Bleeding Score (0–3): the figure shows the absence of intergroup differences at all the evaluation times (\(p>0.05\)). As to intragroup differences, a progressive significant reduction in the index was assessed in the trial group but not in the control one. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Group** & **Time** & **Mean** & **St Dev** & **Min** & **Median** & **Max** & **Intragroup Differences*** & **Intergroup Differences*** \\ \hline Trial Group & T0 & 1.86 & 0.46 & 1.00 & 2.00 & 3.00 & A & T0: ns \\  & T1 & 1.16 & 0.89 & 0.00 & 1.00 & 3.00 & B & T1: ns \\  & T2 & 0.70 & 0.83 & 0.00 & 0.50 & 3.00 & C & T2: ns \\ Placebo Group & T0 & 1.43 & 0.66 & 0.55 & 1.25 & 2.50 & D & \\  & T1 & 1.50 & 0.78 & 0.60 & 1.25 & 3.00 & D & \\  & T2 & 1.40 & 0.71 & 0.50 & 1.21 & 3.00 & D & \\ \hline \hline \end{tabular}  
* Different letters show statistically significant differences among the time frames (\(p<0.05\));
* ns = not significant.  
\end{table} 
Table 5: Descriptive statistics of Bleeding Score measurements (BS). properties. However, the possible role for the maintenance of oral implants undergoing a reversible inflammatory process seems to be poorly explored in the literature so far. The null hypotheses of this study were rejected. As regards the intragroup comparisons, we can state that the application of ozonized water in the trial group succeeded in reducing all the clinical indexes tested, with a progressive decrease from baseline to the subsequent two months (except when considering the period T1-T2 for the Plaque Index). Conversely, no significant difference occurred for the control group. Therefore, ozone has reported a beneficial effect on the peri-implant status, whereas pure water did not cause any significant variation, as expected. Despite this apparent positive outcome for the ozonized water, the evidence obtained from the subsequent intergroup comparisons seems to point towards a different direction. No significant differences were assessed comparing each respective time frame for the two groups, except for PPD at T2. Only in this latter case, in fact, did ozonized water manage to cause a more significant clinical improvement with respect to the pure water. Therefore, on the basis of the present results, ozonized water improved all the clinical indexes tested, whereas the pure water had no effect on the peri-implant status, but, except for the better outcome reported for PPD at the 2-month time, any relevant action has resulted in this study for ozone therapy on the peri-implant sites affected by mucositis. However, it is important to consider that for PPD measurements the presence of statistically significant differences does not directly correspond to important differences at a clinical level.