Preparation and osteogenic properties of nanocomposite hydrogel beads loaded with nanometric bioactive glass particles.

Bone reconstruction in the oral and maxillofacial region presents particular challenges related to the development of biomaterials with osteoinductive properties and suitable physical characteristics for their surgical use in irregular bony defects. In this work, the preparation and bioactivity of chitosan-gelatin (ChG) hydrogel beads loaded with either bioactive glass nanoparticles (nBG) or mesoporous bioactive glass nanospheres (nMBG) were studied.In vitrotesting of the bionanocomposite beads was carried out in simulated body fluid, and through viability and osteogenic differentiation assays using dental pulp stem cells (DPSCs).In vivobone regenerative properties of the biomaterials were assessed using a rat femoral defect model and compared with a traditional maxillary allograft (Puros®). ChG hydrogel beads containing homogeneously distributed BG nanoparticles promoted rapid bone-like apatite mineralization and induced the osteogenic differentiation of DPSCsin vitro. The bionanocomposite beads loaded with either nBG or nMBG also produced a greater bone tissue formationin vivoas compared to Puros® after 8 weeks of implantation. The osteoinductivity capacity of the bionanocomposite hydrogel beads coupled with their physical properties make them promissory for the reconstruction of irregular and less accessible maxillary bone defects.

Biomechanical behavior of an alveolar graft under maxillary therapies.

Cleft lip and palate is a congenital defect that affects the oral cavity. Depending on its severity, alveolar graft surgery and maxillary orthopedic therapies must be carried out as a part of the treatment. It is widely accepted that the therapies should be performed before grafting. Nevertheless, some authors have suggested that mechanical stimuli such as those from the maxillary therapies could improve the success rate of the graft. The aim of this study is to computationally determine the effect of maxillary therapies loads on the biomechanical response of an alveolar graft with different degrees of ossification. We also explore how the transverse width of the cleft affects the graft behavior and compare results with a non-cleft skull. Results suggest that stresses increase within the graft as it ossifies and are greater if maxillary expansion therapy is applied. This has consequences in the bone remodeling processes that are necessary for the graft osseointegration. Maxillary orthopedic therapies after graft surgery could be considered as a part of the treatment since they seem to act as a positive extra stimulus that can benefit the graft.

Computer-Aided Design/Computer-Aided Manufacturing Milling of Allogeneic Blocks Following Three-Dimensional Maxillofacial Graft Planning.

Despite the advent of stereolithography in craniofacial surgery for creating surgical guides and custom synthetic scaffolds, little is known about the feasibility of computer-aided design/computer-aided manufacturing (CAD/CAM) milling of freeze-dried allogeneic bone blocks following previously designed volumetric graft plans. The aim of this technical report is to present a methodology for CAD/CAM milling to achieve the volume and shape of allogeneic bone blocks as estimated by using a virtual planning software. To perform the current methodology, an ex vivo simulation was performed. The milled allogeneic block presented satisfactory dimensional accuracy as compared with the respective three-dimensional virtual model.

Horizontal Bone Reconstruction on sites with different amounts of native bone: a retrospective study.

The lack of guidelines for bone augmentation procedures might compromise decision making in implantology. The objective of this study was to perform a retrospective study to verify the outcomes of horizontal bone reconstruction in implant dentistry with different types of materials and amounts of native bone in the recipient bed to allow for a new guideline for horizontal bone reconstruction. One hundred preoperative CT scans were retrospectively evaluated and categorized in accordance to horizontal bone defects as presence (Group P) or absence (Group A) of cancellous bone in the recipient bed. Different approaches were used to treat the edentulous ridge and the outcomes were defined either as satisfactory or unsatisfactory regarding the possibility of implant placement. The percentage distribution of the patients according to the presence or absence of cancellous bone was 92% for Group P and 8% for Group A. In Group P, 98% of the patients had satisfactory outcomes, and the use of autografts had 100% of satisfactory outcomes in this group. In Group A, 37.5% of the patients had satisfactory outcomes, and the use of autografts also yielded 100% of satisfactory outcomes. The use of allografts and xenografts in Group A had 0% and 33.3% of satisfactory outcomes, respectively. Therefore, it seems reasonable to speculate that the presence of cancellous bone might be predictive and predictable when the decision includes bone substitutes. In cases of absence of cancellous bone in the recipient bed, the use of a vitalized graft seems to be mandatory.

Antral Wall Approach for Reconstruction of Orbital Floor Fractures Using Anterior Maxillary Sinus Bone Grafts.

Isolated orbital wall fractures account for 4% to 16% of all facial fractures. Even a modest change in the position of the bony walls can have a significant impact on orbital volume and globe position. Alloplastic materials or autogenous bone grafts such as the antral maxillary wall can be used to reconstruct small- to medium-size orbital fractures. The main advantage of an antral wall graft is the intraoral approach with minimal morbidity. Nine patients underwent repair of orbital floor fractures using the extraoral and the intraoral antral wall approach. The patients underwent preoperative computed tomography imaging and a minimum of 1 year follow-up. The size of the defects ranged from 0.5 to 1.4 cm. Two patients experienced minor immediate postoperative complications; infraorbital hypoesthesia. On follow-ups, none of our patients suffered from ocular movement restrictions or complications regarding the maxillary antral wall approach. The use of harvested bone grafts from the anterolateral wall of the maxillary sinus is a promising approach for the reconstruction of small- to mid-size orbital floor defects with minimal complications and excellent cosmetic and functional results.

Endoscopic Repair of Persistent Oroantral Communications Using the Caldwell-Luc Approach.

In this article, a novel endoscopic technique used to close oro-antral fistulas will be described. In the technique described here, 24 cases were surgically treated between May 2011, and November 2014. Under endonasal endoscopic examination following partial inferior uncinectomy, the natural ostium of the maxillary sinus was identified; through this tract, a curved aspirator was advanced into the sinus. If present, we extracted endoscopically tissues causing obliteration of the ostium through the Caldwell-Luc antrostomy, taking care to preserve the integrity of the natural ostium. In the technique described here, endoscopic examination using the Caldwell-Luc approach, the inside of the maxillary sinus is explored fully, existing infection and polyps are eliminated locally, and natural patency of the maxillary sinus ostium can be achieved. The graft used to obliterate the oroantral fistula can be easily harvested from the bone of the anterior wall of the maxillary sinus by accessing the surgical entry tract.

Bone Regeneration using Silk Hydroxyapatite Hybrid Composite in a Rat Alveolar Defect Model.

Background: To overcome the limited source of autogenous bone in bone grafting, many efforts have been made to find bone substitutes. The use of hybrid composites of silk and hydroxyapatite to simulate natural bone tissue can overcome the softness and brittleness of the individual components. Methods: Critical-sized, 7 x 4 x 1.5 mm alveolar defects were created surgically in 36 Sprague-Dawley rats. Three treatment groups were tested: an empty defect group (group I), a silk fibrin scaffold group (group II), and a hydroxyapatite-conjugated silk fibrin scaffold group (group III). New bone formation was assessed using computed tomography and histology at 4, 8, and 12 weeks, and semi-quantitative western blot analysis was done to confirm bone protein formation at 12weeks. Statistical analysis of new bone formation was done using the Kruskal-Wallis test. Results: Radiomorphometric volume analysis revealed that new bone formation was 64.5% in group I, 77.4% in group II, and 84.8% in group III (p=0.027) at 12 weeks. Histologically, the osteoid tissues were surrounded by osteoblasts not only at the border of the bone defect but in the center of the scaffold implanted area in group III from week 8 on. Semi-quantitative western blotting revealed that osteocalcin expression in group III was 1.8 times higher than group II and 2.6 times higher than group I. Conclusions: New bone formation was higher in hybrid scaffolds. Both osteoconduction at the defect margin and osteoinduction at the center of the defect were confirmed. There were no detected complications related to foreign body implantation.

Horizontal Bone Reconstruction on sites with different amounts of native bone: a retrospective study

Abstract: The lack of guidelines for bone augmentation procedures might compromise decision making in implantology. The objective of this study was to perform a retrospective study to verify the outcomes of horizontal bone reconstruction in implant dentistry with different types of materials and amounts of native bone in the recipient bed to allow for a new guideline for horizontal bone reconstruction. One hundred preoperative CT scans were retrospectively evaluated and categorized in accordance to horizontal bone defects as presence (Group P) or absence (Group A) of cancellous bone in the recipient bed. Different approaches were used to treat the edentulous ridge and the outcomes were defined either as satisfactory or unsatisfactory regarding the possibility of implant placement. The percentage distribution of the patients according to the presence or absence of cancellous bone was 92% for Group P and 8% for Group A. In Group P, 98% of the patients had satisfactory outcomes, and the use of autografts had 100% of satisfactory outcomes in this group. In Group A, 37.5% of the patients had satisfactory outcomes, and the use of autografts also yielded 100% of satisfactory outcomes. The use of allografts and xenografts in Group A had 0% and 33.3% of satisfactory outcomes, respectively. Therefore, it seems reasonable to speculate that the presence of cancellous bone might be predictive and predictable when the decision includes bone substitutes. In cases of absence of cancellous bone in the recipient bed, the use of a vitalized graft seems to be mandatory.

First Lower Two-Thirds Osteomyocutaneous Facial Allograft Perfused by a Unilateral Facial Artery: Outcomes and Vascularization at 1 Year after Transplantation.

BACKGROUND: Facial allotransplantation provides a unique opportunity to restore facial form and function in severely disfigured patients. Using a single unilateral facial artery for vascularization can significantly reduce surgical duration and thus facilitate the practice of face transplantation. METHODS: A 33-year-old man with a history of high-energy ballistic trauma received a facial allograft comprising the lower two-thirds of the face, including maxilla and mandible. Vascular anastomoses involved one unilateral facial artery and two veins. Vascularization patterns, airway volume, and facial functions were assessed before and 1 year after transplantation. In addition, immunosuppressive therapy and rejection episodes were recorded. RESULTS: One year after transplantation, the facial allograft is well perfused and gradually improving in function. Unilateral facial artery anastomosis remains patent and collateralization with the contralateral side is taking place through collaterals of the submental arteries. Bony perfusion of the maxilla and mandible is provided periosteally. Bilateral venous outflow is evident. Airway volume is significantly increased compared with before transplantation, and gastrostomy and tracheostomy tubes have been securely removed. The recipient has gained the abilities to smell, speak, feel, and grimace 1 year after transplantation. Steroids were successfully weaned after 9 months, leaving the patient on dual immunosuppressive therapy with tacrolimus and mycophenolate mofetil. Two rejection episodes occurred, of which one was treated by steroid pulse and the other by adjusting the maintenance therapy. CONCLUSIONS: In this patient, a facial allograft comprising the lower two-thirds of the face including the maxilla and mandible is sufficiently perfused by one unilateral facial artery. Bilateral venous outflow, however, seems to be necessary. Facial allotransplantation can significantly and securely improve facial form and function. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Maxillofacial Prosthesis in Dentofacial Traumas: A Retrospective Clinical Study and Introduction of New Classification Method.

Background. Maxillofacial trauma represents a field of common interest as regards both the maxillofacial surgery and prosthodontics, especially for the functional and aesthetic stomatognathic rehabilitation. This condition necessitates relationship between maxillofacial surgeon and prosthodontist, to achieve the ultimate treatment goal. Purpose. The purpose of this study is to make predictable patients outcomes classifying their clinical data, using certain parameters and introducing a new classification method. Materials and Methods. We have chosen 7 parameters to classify the entity of the damage of these patients and to make their treatment and their prognosis predictable: number of teeth lost (T1-T4), upper/lower maxilla (U/L), alveolar/basal bone (Alv/B), gingival tissues (G), soft tissues (S), adult/child (a/c), and reconstructed patient (R). Results and Conclusions. The multidisciplinary approach and the collaboration between multiple clinical figures are therefore critical for the success of the treatment of these patients. The presence and quantification of above parameters influence the treatment protocol; patients undergo different levels of treatment depending on the measured data. The recognition of certain clinical parameters is fundamental to frame diagnosis and successful treatment planning.

[Surgical reconstruction of maxillary defects using a computer-assisted techniques].

The maxilla is the most important bony support of the mid-face skeleton and is critical for both esthetics and function. Maxillary defects, resulting from tumor resection, can cause severe functional and cosmetic deformities. Furthermore, maxillary reconstruction presents a great challenge for oral and maxillofacial surgeons. Nowadays, vascularized composite bone flap transfer has been widely used for functional maxillary reconstruction. In the last decade, we have performed a comprehensive research on functional maxillary reconstruction with free fibula flap and reported excellent functional and acceptable esthetic results. However, this experience based clinical procedure still remainssome problems in accuracy and efficiency. In recent years, computer assisted techniques are now widely used in oral and maxillofacial surgery. We have performed a series of study on maxillary reconstruction with computer assisted techniques. The computer assisted techniques used for maxillary reconstruction mainly include: (1) Three dimensional (3D) reconstruction and tumor mapping: providing a 3D view of maxillary tumor and adjacent structures and helping to make the diagnosis of maxillary tumor accurate and objective; (2) Virtual planning: simulating tumor resection and maxillectomy as well as fibula reconstruction on the computer, so that to make an ideal surgical plan; (3) 3D printing: producing a 3D stereo model for prebending individualized titanium mesh and also providing template or cutting guide for the surgery; (4) Surgical navigation: the bridge between virtual plan and real surgery, confirming the virtual plan during the surgery and guarantee the accuracy; (5) Computer assisted analyzing and evaluating: making a quantitative and objective of the final result and evaluating the outcome. We also performed a series of studies to evaluate the application of computer assisted techniques used for maxillary reconstruction, including: (1) 3D tumor mapping technique for accurate diagnosis and treatment of maxillary tumor; (2) Maxillary reconstruction with free fibula flap used computer assisted techniques; (3) Computer assisted orbital floor reconstruction after maxillectomy. The results suggested that computer assisted techniques could significantly improve the clinical outcome of maxillary reconstruction.

New bone formation induced by surface strontium-modified ceramic bone graft substitute.

OBJECTIVES: This study assessed the effect of surface strontium ion (Sr) modification on the osteogenic activity of an osteoconductive ceramic bone graft substitute with the hope of using the bone healing effect of Sr for potential application in periodontal and maxillofacial regenerative surgery. MATERIALS AND METHODS: A simple wet chemical treatment was employed to deliver Sr to the surface of particulate porcine bone graft. The osteogenic activity of surface Sr-modified bone substitute was compared in vitro and in vivo with that of unmodified ceramic bone, other clinically available synthetic bone or osteoinductive allograft bone. RESULTS: The resultant bone substitute showed the formation of Sr-containing microstructured surface layer along with the formation of additional nanostructures and displayed sustained Sr release. Sr modification promoted the osteogenic differentiation of bipotential ST2 stem cells. Sr-modified bone substitute increased the amount of newly formed bone at early healing period in calvarial defect of rabbits. CONCLUSIONS: These results suggest that the surface Sr modification by wet chemical treatment is a promising approach to enhance the early bone healing capacity of osteoconductive ceramic bone substitutes.

[Le Fort I osteotomies combined with post-operative bone grafts]. / Greffes osseuses réalisées à partir des résidus peropératoires lors des ostéotomies de Le Fort I.

INTRODUCTION: We present and assess a surgical technique for maxillary auto-bone grafting concomitantly with Le Fort I osteotomy. The graft has 2 main objectives: to fill in the space between the 2 advanced segments of the maxilla to help bone consolidation, and to increase the volume of the malar, para-nasal spaces to improve post-operative esthetic results. TECHNICAL NOTE: Bone fragments, removed during the Le Fort I osteotomy, are stored and wrapped in a Surgicel(®) sheet, then grafted in the space left by the osteotomy, or on the anterior maxilla in the para-nasal area or on the malar bone. One hundred and twenty-three patient records, operated from 2007 to 2012, were collected to assess the post-operative course retrospectively. The post-operative course was uneventful in 93.5% of cases. About 8.4% of patients (7 cases) presented with a persistent post-operative maxillary edema. 1 patient (1.2%) presented with a sinus infection without any determined etiology. The grafts were all osteointegrated at the end of follow-up. DISCUSSION: The technique is simple and quickly performed; it improves bone healing and cosmetic results, without increasing morbidity or surgical time. It is a good alternative to bone grafts from a secondary sample site. It can be applied to all Le Fort I osteotomies.

Surgical techniques for maxillary bone grafting - literature review.

For oral rehabilitation with implant-supported prostheses, there are required procedures to create the bone volume needed for installation of the implants. Thus, bone grafts from intraoral or extraoral donor sites represent a very favorable opportunity. This study aimed to review the literature on the subject, seeking to discuss parameters for the indications, advantages and complications of techniques for autogenous bone grafts.

Found in space: computer-assisted orthognathic alignment of a total face allograft in six degrees of freedom.

PURPOSE: Full facial osteomyocutaneous transplantation requires correct 3-dimensional (3D) alignment of donor osseous structures to a new cranial base with minimal reference points and 6 degrees of potential movement. We investigated whether computer-assisted design and manufacturing (CAD/CAM) could enable accurate placement of the facial skeleton. MATERIALS AND METHODS: A prospective single-cohort study of Le Fort III-based maxillary-mandibular segment allotransplantation was performed in 5 cadaver pairs and 1 clinical pair. The osteotomies were modeled using computed tomography (CT) data and 3D modeling software and then translated to the donor-recipient pairs using surgical navigation and osteotomy cutting guides. The predicted values were calculated about all rotational axes (pitch, yaw, and roll) and along all translational axes (vertical, horizontal, and anteroposterior) and used as the independent variable. The primary outcome variable of the actual postoperative CT values was compared for fidelity to the prediction using the intraclass correlation coefficient (ICC). The similarity to the donor versus recipient values was calculated as a secondary independent variable, and both predicted and actual measurements were compared with it as a percentage. RESULTS: The postoperative fidelity to the plan was adequate to excellent (ICC 0.520 to 0.975) with the exception of lateral translation (2.94 ± 1.31 mm predicted left vs 3.92 ± 2.17 mm right actual displacement; ICC 0.243). The predicted and actual values were not consistently skewed toward the donor or recipient values. CONCLUSIONS: We have demonstrated a novel application of CAD/CAM that enables orthognathic alignment of a maxillary-mandibular segment to a new cranial base. Quantification of the alignment in all 6 degrees of freedom delivers precise control compared with the planned changes and allows postoperative quality control.

Characterization, prophylaxis, and treatment of infectious complications in craniomaxillofacial and upper extremity allotransplantation: a multicenter perspective.

BACKGROUND: Vascularized composite allotransplants consist of heterogeneous tissues from different germ layers, which include skin, muscle, bone, fat, nerves, and lymph nodes. The antigenic diversity of these tissues, particularly of the highly immunogenic skin component, necessitates potent immunosuppressive regimens similar to that of some solid organ transplants. Indeed, the lifelong, high-dose, multidrug immunosuppressive protocols expose vascularized composite allotransplant recipients to considerable risk of infectious, metabolic, and neoplastic sequelae. In this article, the authors review the infectious risk to patients after vascularized composite allotransplantation, with special attention to the somewhat limited experience with the prophylaxis and treatment of infections after this innovative reconstructive surgery. METHODS: A review of the literature was undertaken to elucidate the characterization, prophylaxis, and treatment of all documented infectious complications. RESULTS: Infections in face and hand vascularized composite allotransplants follow a course similar to that of solid organ transplants. Several differences exist, including the unique flora of craniomaxillofacial transplants, the increased risk of donor-derived infections, and the alteration of the risk-to-benefit ratio for cytomegalovirus infections. CONCLUSIONS: The patient with a face or limb transplant has many of the same infectious risks as a lung transplant recipient, which include bacterial, viral, and fungal infections. Because of the anatomy, mucosal exposure, and differing donor flora, however, the face or limb transplant is susceptible to invasive diseases from a variety of microbes.

Surgical techniques for maxillary bone grafting - literature review / Técnicas cirúrgicas para a enxertia óssea dos maxilares - revisão da literatura

For oral rehabilitation with implant-supported prostheses, there are required procedures to create the bone volume needed for installation of the implants. Thus, bone grafts from intraoral or extraoral donor sites represent a very favorable opportunity. This study aimed to review the literature on the subject, seeking to discuss parameters for the indications, advantages and complications of techniques for autogenous bone grafts.

Para a reabilitação bucal com as próteses implantossuportadas é necessário a realização de procedimentos para criar o volume ósseo necessário para a instalação dos implantes. Com isso, os enxertos ósseos provenientes de áreas doadoras intrabucais ou extrabucais, representam uma possibilidade bastante favorável. O presente trabalho objetivou realizar uma revisão da literatura em que procurou discutir parâmetros para as indicações, as vantagens e complicações para as técnicas dos enxertos ósseos autógenos.

Healing properties of implants inserted concomitantly with anorganic bovine bone. A histomorphometric human study.

BACKGROUND: The present prospective, randomized, double-blind study evaluated the bone-forming process around implants inserted simultaneously with anorganic bovine bone (ABB) in sinus grafting. METHODS: A total of 18 threaded mini-implants with Osseotite (O) and Nanotite (N) surfaces were placed in seven patients (nine sites). After 12 months, the implants were retrieved and processed for histological analysis. A total of 18 cutting and grinding sections were investigated with bright-field light microscopy, circularly polarized light microscopy (CPLM), confocal scanning laser microscope (CSLM), and scanning electron microscope (SEM) with energy dispersive spectrometer (EDS). RESULTS: The bone-to-implant contact rate in native crestal bone was 62.6 ± 0.4% for N implants and 54.3 ± 0.5% for the O implants (p = 0.001). The collagen fibre density, as assessed by CPLM, was 79.8 ± 6.0 nm for the N group and 74.6 ± 4.6 nm for the O group (p < 0.05). Line scan EDS starting from ABB to newly formed bone showed a decrease in calcium content and an increase of carbon while phosphorus content was constant. CONCLUSIONS: While the N surface improved the peri-implant endosseous healing properties in the native bone, when compared to the O surface, it did not improve the healing properties in the bone-graft area.

Biological properties of solid free form designed ceramic scaffolds with BMP-2: in vitro and in vivo evaluation.

Porous ceramic scaffolds are widely studied in the tissue engineering field due to their potential in medical applications as bone substitutes or as bone-filling materials. Solid free form (SFF) fabrication methods allow fabrication of ceramic scaffolds with fully controlled pore architecture, which opens new perspectives in bone tissue regeneration materials. However, little experimentation has been performed about real biological properties and possible applications of SFF designed 3D ceramic scaffolds. Thus, here the biological properties of a specific SFF scaffold are evaluated first, both in vitro and in vivo, and later scaffolds are also implanted in pig maxillary defect, which is a model for a possible application in maxillofacial surgery. In vitro results show good biocompatibility of the scaffolds, promoting cell ingrowth. In vivo results indicate that material on its own conducts surrounding tissue and allow cell ingrowth, thanks to the designed pore size. Additional osteoinductive properties were obtained with BMP-2, which was loaded on scaffolds, and optimal bone formation was observed in pig implantation model. Collectively, data show that SFF scaffolds have real application possibilities for bone tissue engineering purposes, with the main advantage of being fully customizable 3D structures.

Immediate implant placement in the maxillary central incisor region: a case report.

PATIENT: A 67-year-old female with root fracture of the maxillary central incisor underwent implant placement immediately after extraction, with the goal of shortening the treatment period. The superstructure was placed on the implant after a 4-month healing period. Review 5 years after implant loading revealed no clinical problems. DISCUSSION AND CONCLUSION: The treatment time was shortened effectively by the flapless immediate post-extraction placement procedure. Immediate post-extraction implant placement based on proper examination and diagnosis would reduce the patient burden.