## 1 Introduction  
Alveolar socket preservation techniques were introduced for ridge augmentation and prevention of the alveolar bone resorption after tooth extraction with bone substitute materials with or without membrane barrier use [1; 2; 3]. The tooth grafting procedure has been introduced by [PERSON] et al. more than 50 years ago, when they discovered the osteoinduction potential of demineralized dentin matrix [4; 5]. Recently, [PERSON] et al. demonstrated the presence of bone morphogenetic proteins (BMPs) in human dentin matrix. In particular, bone formation and osteoblasts' presence in rat muscles after demineralized human dentin matrix graft were observed [6]. It was clear that both bone and dentin matrix contained fundamental growth factors for bone regeneration. It represented an efficient reserve of BMPs and bioactive growth factors (GFs), such transforming growth factor-B (TGF-B), which are well known to be involved in bone repairing processes [7]. Some authors theorized that the demineralization process allows better bone augmentation than non-demineralized dentin [8]. Moreover, the chemical composition of bone and dentin was almost the same as the presence of an inorganic portion made of hydroxyapatite and an organic one, mainly composed of collagen type 1 and other secondary proteins. Heterologous or alloplastic grafting materials, on the other hand, have been used for bone augmentation procedures from more than 35 years, but they work as a mechanical scaffold for host cells and do not offer any osteoinductive stimulus [9; 10; 11; 12]. The efficacy and safety of autogenous partially demineralized dentin matrix prepared chairside, for clinical application in bone regeneration procedures related to implant dentistry, including socket preservation, alveolar ridge augmentation, and maxillary sinus floor augmentation were recently demonstrated in some human studies [13; 14]. Recently, an innovative medical device (TT TOOTH TRANSFORMER SRL, Via Washington, 59--Milan, Italy) to obtain suitable tooth graft materials starting from the whole tooth of the patient was introduced to the market. This device ensures completely automated disinfection, grinding, and demineralizing processes without any possible mistake induced by human manipulation of the process. This new device represents an advanced system in the area of tissue engineering because it is able to process and transform extracted tooth into useful bone graft material in a short time. The graft material, produced starting from the whole tooth, showed high wettability that allowed an easy handling and positioning on a host site [15]. A previous case series described the successful clinical outcomes of bone regeneration after autologous tooth grafting using this new device and demonstrated the complete filling of bone defects by hard tissue without any complications [16].  
The aim of the study is to evaluate the tooth extracted use for the first time as autologous tooth graft after endodontic root canal therapies used for socket preservation with histological analysis. The second outcome is to evaluate the implant insertion in regenerated vital bone with six months of follow up.