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Additive manufacturing (AM) enables the production of complex structured parts with tailored properties. Instead of manufacturing parts as fully solid, they can be infilled with lattice structures to optimize mechanical, thermal, and other functional properties. A lattice structure is formed by the repetition of a particular unit cell based on a defined pattern. The unit cell's geometry, relative density, and size dictate the lattice structure's properties. Where certain domains of the part require denser infill compared to other domains, the functionally graded lattice structure allows for further part optimization. This manuscript consists of two main sections. In the first section, we discussed the dual graded lattice structure (DGLS) generation framework. This framework can grade both the size and the relative density or porosity of standard and custom unit cells simultaneously as a function of the structure spatial coordinates. Popular benchmark parts from different fields were used to test the framework's efficiency against different unit cell types and grading equations. In the second part, we investigated the effect of lattice structure dual grading on mechanical properties. It was found that combining both relative density and size grading fine-tunes the compressive strength, modulus of elasticity, absorbed energy, and fracture behavior of the lattice structure.

Purpose: This study aimed to evaluate the osteoconductive features of Bio-Oss Collagen in large critical-size defects (8 mm)., Materials and Methods: Thirty-six adult Wistar Albinus male adult rats were carried out a critical-size defect with a trephine bur of 8 mm in the calvaria. Groups were divided depending on the filling biomaterial as follows: group BO: Bio-Oss (n = 18); group BOC: Bio-Oss Collagen (n = 18). After 7, 30, and 60 days, 6 rats of each group were euthanized with anesthetic overdose. Specimens were laboratory processed for histomorphometric analysis. Histomorphometric data were statistically analyzed by analysis of variance and post-Tukey test (P < 0.05)., Results: Statistical differences were found in new bone formation just in the intragroup comparison among periods after 7 and 60 postoperative days, indicating more new bone formation after 60 days (Tukey test, P = 0.029)., Conclusion: Under the limitation of this research, it could be concluded that Bio-Oss and Bio-Oss Collagen in this experimental model did not show osteoconductive features.

Dentigerous cysts are defined as a cyst originated by separation of the follicle of dental crown of a tooth unerupted. Although most dentigerous cysts are considered developmental cysts, some cases seem to have an inflammatory origin. The aim of this study was to show a case of an 8-year-old patient, male, presenting a lesion in maxilla with large proportions. Computed tomography scans showed a hypodense image, well-defined, associated to unerupted teeth. The case was treated by enucleation of the lesion under local anesthesia. Histopathological examination confirmed the diagnostic suspicious of dentigerous cyst. Currently, 3-year follow-up period showed no signs of recurrence, and it was observed eruption of the teeth associated to the lesion. This case highlights the importance of the association between clinical and radiographic analysis together to the surgical findings, aiming the best treatment for the patient.

Factors associated with the diagnosis, aetiology, and treatment of mandibular fractures occurring during the postoperative period following the removal of a lower third molar are discussed. The following databases were searched using specific key words: PubMed/MEDLINE, LILACS, Embase, and Scopus. The search yielded 124 cases. Sex, age, side, tooth position and angulation, bone impaction, relationship between the tooth and the inferior alveolar nerve, local pathological conditions, aetiology of the fracture, symptomatology, and time between surgery and fracture, as well as any displacement of the fracture and the treatment of the fracture, were evaluated. Data were tabulated and the χ 2 statistical test was applied (P<0.05). Male patients aged >35 years, with teeth in positions II/III and B/C, complete bony impaction, and local bone-like alterations, were found to have a higher frequency of fracture and pericoronitis (P<0.05). Late fractures generally occurred between the second and fourth postoperative weeks (P<0.05). They were generally not displaced and the typical treatment was the non-surgical approach (P<0.05). It is concluded that the risk of mandibular fracture after extraction is associated with excessive ostectomy and/or local alterations. At-risk patients should be thoroughly briefed on the importance of a proper postoperative diet., (Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Purpose: This study aimed to identify the main indications for the use of recombinant human bone morphogenetic protein-2 (rhBMP-2) for bone repair and maintenance in the maxilla and mandible through a review of clinical trials evaluating the viability of using rhBMP-2 to delay the installation of dental implants, thus allowing satisfactory bone formation and long-term osseointegration., Methods: Literature search of the PubMed/Medline databases was performed using the following MeSH index terms-"bone morphogenetic protein 2" and "dentistry". Only clinical trials necessarily published in English, related to dentistry, and focused on bone reconstruction in critical defects, post-extraction alveoli, increasing the atrophic alveolar ridge, or surgery for maxillary sinus elevation were included, regardless of the age, sex, ethnicity, associated morbidities, or period of publication., Results: Of the 17 studies identified based on the search filters, 2 were excluded. Therefore, 15 studies were finally included in this review., Conclusions: Based on the results of our review, we concluded that the use of rhBMP-2 for the preservation of the alveolar ridge after tooth extraction or for increasing the local defects is safe and viable. The use of rhBMP-2/Bio-Oss® for the elevation of the maxillary sinus membrane is unnecessary; however, it can improve and accelerate the maturation process in cases of guided bone regeneration in peri-implant defects. Compounds comprising rhBMP-2, allogenic bone, and plasma-rich platelet (PRP) can act as autograft substitutes in mandibular critical defects.

Craniofacial trauma can lead to several complications. The combined fractures of anterior and posterior walls of the frontal bone are almost always followed by lesions in nasofrontal orifices and disruption of nasofrontal ostia or ducts, a significant factor for the development of early and late complications after sinus fractures. This article reports a case of trauma patient, who underwent neurological evaluation and at first showed good general condition. Computed tomography noted fracture of the anterior and posterior walls of the frontal sinus and small foci of pneumocephalus in the cerebral cortex. The patient was monitored periodically and 9 days after trauma showed increased areas of pneumocephalus in prefrontal cortex, cerebrospinal fluid draining, and large dura mater lesion, with signs of necrosis and inflammation (meningitis). The necrotic tissues were removed, and dura mater was repaired through the approximation with resorbable wire polyglactin 910 5-0, oxidized cellulose application, and bonding with human fibrin sealant (fibrinogen, thrombin, and calcium chloride). Sinusectomy, frontal sinus, and nasofrontal duct obliteration with pedicled pericranium flap were performed. Tomographically, a reanatomization was noted in frontal region, and a 12-month follow-up showed no complication. The use of fibrin glue to repair dura mater lacerations, as well as the pedicle pericranium flap for frontal sinus and nasofrontal duct obliteration, is an efficient method for treating fractures of the frontal bone.