The bone regeneration is one of the most important challenges for regenerative medicine. In maxillo-facial area, bone resorption of the alveolar crest occurs after tooth extraction and leads to several risks for rehabilitation treatments, including dental implants procedures. Goal of our study was to demonstrate the efficacy of an innovative clinical protocol of bone tissue engineering called Rigenera protocol, aimed to create and optimize bio-complexes constituted by collagen biomaterial and human autologous periosteum-derived micro-grafts. We assessed the capacity of these bio-complexes to prevent the bone resorption in the alveolar crest with respect to simple collagen performing histological evaluations of neo-formed osseous tissue. We demonstrated that autologous bio-complexes significantly reduced the bone resorption of both horizontal and vertical dimension of alveolar crest when compared to collagen alone. We also showed that these bio-complexes accelerate the ossification process triggering the formation of new osseous tissue after 45 days from treatment and increasing the calcified matrix after 60 days and until to 120 days with respect to collagen alone. Taken together, these data showed the efficacy of bio-complexes composed by periosteum-derived micro-grafts and collagen in the alveolar ridge preservation through a reduction of bone resorption and an enhancement of new osseous tissue formation.

Within the limits of the study, treatment with glycine seems appropriate in the maintenance of peri-implant health and more effective than the traditional treatment with plastic curette and chlorhexidine.

Although numerous biomaterials are used for maxillary sinus-lift surgery, the ideal material for such procedures has not yet been identified. Both heterologous and alloplastic bone substitutes have a solely osteoconductive effect and lack the osteoinductive properties of the bone morphogenetic proteins typical of autologous bone. Our group assessed a new alloplastic graft material, poly(lactic-co-glycolic) acid/hydroxyapatite (PLGA/HA), implanted in a human model of maxillary sinus-lift surgery. For this prospective, random, double-blind trial, we used deproteinized bovine bone (DBB) as the comparison material. Radiographic bone vertical height and density were assessed at approximately 28 weeks after grafting using cone-beam computed tomography. The vertical dimension of the regenerated bone was equivalent between the 2 groups. The density of the bone regenerated using PLGA/HA was significantly lower than that obtained with DBB. Despite clinical assessments demonstrating that PLGA/HA has sufficient characteristics for use in sinus-lift surgery, DBB provided greater bone density and an equivalent vertical dimension of grafted bone. Further studies are needed to supplement the radiologic findings with histologic and micromorphometric examinations.

Introduction:Acute Myeloid Leukemia (AML) in pediatric patients is a serious disease, although, for the subgroup of patients who receive proper treatment, a long-term survival rate above 50% is typical. The cycles of chemo- and radiotherapy used to treat AML can impair dental development.Case Report:Herein, we describe the oral condition of a 25-year-old male patient treated for AML with chemo- and radiotherapy from 5 to 7 years of age; his AML has remained in remission for the past 18 years. He had lost only one permanent tooth, but the remaining teeth demonstrated serious deformations and radicular hypoplasia. Two teeth required immediate extraction and subsequent replacement by implant-supported crowns. We found that the decayed, missing, filled teeth (DMFT) index was not representative of the real oral condition. Here, we report the full case and provide a brief review of the literature.Conclusion:Antitumor treatment of pediatric leukemia can induce total impairment of dental development and function. These adverse effects may become clinically evident many years after the resolution of cancer, and can be significantly detrimental to the patient’s quality of life.

Sinus lift augmentation is a procedure required for the placement of a dental implant, whose success can be limited by the quantity or quality of available bone. To this purpose, the first aim of the current study was to evaluate the ability of autologous periosteum-derived micrografts and Poly(lactic-co-glycolic acid) (PLGA) supplemented with hydroxyl apatite (HA) to induce bone augmentation in the sinus lift procedure. Secondly, we compared the micrograft's behavior with respect to biomaterial alone, including Bio-Oss® and PLGA/HA, commercially named Alos. Sinus lift procedure was performed on 24 patients who required dental implants and who, according to the study design and procedure performed, were divided into three groups: group A (Alos + periosteum-derived micrografts); group B (Alos alone); and group C (Bio-Oss® alone). Briefly, in group A, a small piece of periosteum was collected from each patient and mechanically disaggregated by Rigenera® protocol using the Rigeneracons medical device. This protocol allowed for the obtainment of autologous micrografts, which in turn were used to soak the Alos scaffold. At 6 months after the sinus lift procedure and before the installation of dental implants, histological and radiographic evaluations in all three groups were performed. In group A, where sinus lift augmentation was performed using periosteum-derived micrografts and Alos, the bone regeneration was much faster than in the control groups where it was performed with Alos or Bio-Oss® alone (groups B and C, respectively). In addition, the radiographic evaluation in the patients of group A showed a radio-opacity after 4 months, while after 6 months, the prosthetic rehabilitation was improved and was maintained after 2 years post-surgery. In summary, we report on the efficacy of periosteum-derived micrografts and Alos to augment sinus lift in patients requiring dental implants. This efficacy is supported by an increased percentage of vital mineralized tisssue in the group treated with both periosteum-derived micrografts and Alos, with respect to the control group of Alos or Bio-Oss® alone, as confirmed by histological analysis and radiographic evaluations at 6 months from treatment.

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To evaluate the geometric distortion of tilting of mandibular third molars with respect to second molars on panoramic reconstruction. Methods: Cone-beam CT (CBCT) reconstructions of 160 third molars, obtained due to an indication of risk of inferior alveolar nerve damage during surgery, were used. CBCT-reconstructed panoramic images were used as bi-dimensional (2D) images, to avoid distortions other than geometric distortions. The angle between the second and the third molar was measured in 2D and three-dimensional (3D) images. Student's t-test was used to assess the null-hypothesis of no difference between 2D and 3D measurements. Results: A significant mean difference (−2.3° ± 6.3°) between 2D and 3D measurements was found, with an absolute error of 3.6° ± 5.7° and a relative error of 10%. These findings comprehensively explain the geometric distortion on panoramic radiographs. conclusions: Although a widely used and undoubtedly useful tool for diagnosis and surgical planning of mandibular third molar extractions, panoramic reconstruction are biased from geometric distortion that may influence surgical planning.