## 4 Discussion  
Infections occurring in the oral cavity represent one of the most frequent concerns in dental clinical practice, and many strategies have been proposed to avoid this outcome, such as the use of anti-infective materials [11]. In addition to the colonization of teeth by cariogenic bacteria resulting in carious lesions, specific microorganisms can attack the periodontal tissues. In the presence of poor immune defenses and other eventual risk factors (such as improper oral hygiene or the habit of smoking), bacterial colonization can advance until causing a dysbiosis leading to periodontal disease [12]. Accordingly, it is fundamental for patients to properly carry out correct domiciliary oral hygiene maneuvers aimed at preventing this progression. In case this condition should occur, the conventional treatment for periodontal patients is based on a mechanical therapy (scaling and root planing, SRP) which is aimed at removing plaque/calculus and smoothing infected dental roots surfaces [4]. However, the management of periodontal disease cannot be simply based solely on professional treatment; patients must be directly involved in the therapeutic protocol, thus performing correct domiciliary hygiene procedures with specific products, as prescribed by the clinician [13]. On the basis of this consideration, a correct oral hygiene routine appears to be a fundamental preventive procedure, both to avoid the onset of periodontitis as well as to avoid a relapse when the pathology is under control. This is particularly true especially for patients at high risk of periodontal inflammation, such as orthodontic patients or those having a periodontitis not yet diagnosed or those with predisposing systemic diseases [14]. Accordingly, the aim of the present randomized clinical trial was to evaluate different toothpastes used as a domiciliary means to pursue a good oral hygiene status in periodontal patients undergoing recurrent treatments of SRP. Specifically, the purpose was to assess the effect of the different toothpastes on the management of gingival bleeding. Accordingly, only bleeding indexes were chosen as outcomes of the present research. The first null hypothesis of the study was rejected, whereas the second one was partially rejected. All the experimental toothpastes tested (i.e., Biorepair Gum Protection, Biorepair Plus Parodontgel, and Biorepair Peribioma PRO) resulted in being highly effective in varying all three of the periodontal bleeding indexes considered. The three agents equally modified the modified sulcus bleeding index (mSBI), with a significant reduction in this parameter between the baseline appointment and the following visit after 15 days. No further changes were detected during the subsequent follow up at 3 and 6 months; therefore, the effect of the toothpastes was exerted mainly in the short-term of daily use and was maintained unaltered at least for the six months of follow up here considered. With regard to the full-mouth bleeding score (FMBS), the toothpastes Biorepair Gum Protection and Biorepair Plus Parodontgel significantly reduced this index between T\({}_{0}\) and T\({}_{1}\), with no further reductions after this last time. In addition, no significant intergroup differences were noticed between the two abovementioned agents. However, it was Biorepair Peribioma PRO that showed the best effect with respect to the other experimental products by strongly reducing FMBS after baseline; here again, this outcome was maintained during the whole follow-up, with no variations in the meantime. As to bleeding on probing (BoP), all the three pastes were again successful in reducing this index, especially Biorepair Plus Parodontgel and Biorepair Peribioma PRO. As previously reported for the other variables, the effect was seen immediately after the baseline time, whereas it remained unaltered subsequently.