## 2 Material and Methods  
Group A patients  
Group A included 120 post-extractive surgical sites of mandibular molars, two for each patient, one on each side of the jaw, to obtain an in-patient comparison among case (receiving gel) and control (not receiving gel). Group B included 60 post-extractive sites of molars in oncologic patients receiving intravenous bisphosphonates (BPs) and considered at high risk for medication-related osteonecrosis of the jaw (MRONJ); teeth extractions were performed after a drug-free period of 3 months with suspension of all antiresorptive therapies [12]. Thirty post-extractive sockets were inserted in the experimental subgroup and treated with Aminogam(r) (five applications per day) until the complete gingival closure. Group C patients  
Group C included 100 cases of MRONJ who underwent surgical resection of necrotic bone; of these, 50 belonged to the experimental subgroup which received Aminogam(r) gel (five applications per a day) after surgery until the full thickness closure of the mucosal flaps. Group D patientsGroup D included 80 cases of endosseous dental implants with gingival flap elevation; of these, 40 were inserted into the experimental subgroup, which was treated with Aminogam(r) (five applications per day) until the gingival healing. Group E patients  
Group E included 140 cases of diode laser excisions of proliferating oral mucosa lesions (neoplastic and not) without direct closure of surgical margins by stitches (wound diameter had an average size of 30 mm); the 70 cases of the experimental subgroup were treated with Aminogam(r) gel (five applications per day) until the complete reconstruction of a normally colored covering mucosa. Group F patients  
Group F included 40 cases of diode laser photocoagulation of slow flow vascular malformations (lesion diameter ranging from 20 to 40 mm); the 20 cases of the experimental subgroup received application of Aminogam(r) gel (five applications per day) until the complete healing of the irradiated area. Group G patients  
Group G included 40 cases of bone lesions (benign and/or malignant odontogenic or not odontogenic tumors, and odontogenic cysts) radiographically appearing as radiolucent areas larger than 50 mm in diameter, and all surgically removed. The 20 cases of the experimental subgroup received Aminogam(r) gel directly within bone cavity immediately after lesion removal and also upon receiving stitches until the complete gingival closure. Healing time evaluation after oral surgery  
To assess the effectiveness of Aminogam(r) in terms of reducing of the healing time (HT), we compared the average time elapsed between the oral surgical procedure and the clinical healing of the covering soft tissue among control and experimental subgroups, and compared using the t-test or the Mann-Whitney U test when the normality test failed. A P value of less than 0.05 was considered to indicate statistical significance. Analyses were carried out with the use of SPSS 23 for Windows. Furthermore, three months after implant insertion in Group D patients, gingival tissues were removed during fixture exposition, collected and then sent for histological examination (conventional and confocal laser scanning microscopic analysis) to histologically compare soft tissues treated with Aminogam(r) gel and those which were not, approximately 4-6 months after surgery. The surgical samples were formalin-fixed, paraffin embedded, cut at 4 um thickness and stained with two different methods: hematoxylin-eosin for conventional optical microscopy and picrosirius red for Confocal Scanning Laser Microscopy (CSLM) analysis performed by a Nikon Eclipse E600 microscope (Nikon Corporation, Tokyo--Japan), equipped with Argon-ion and Helio-Neon lasers, which allows both optical and confocal laser scanning analyses. This study was performed in accordance with the principles of the Declaration of Helsinki and has been approved by our institution's ethical committee (Study n\({}^{\circ}\)3134, Prot. 21/C.E.