Manejo de un defecto estético en maxilar anterior con injertos de tejidos duros y blandos e inserción diferida de un implante dental. A propósito de un caso / Management of an aesthetic defect in the anterior maxilla with hard and soft tissue grafts and delayed insertion of a dental implant. Case report

Introducción: Hay alteraciones óseas en las crestas alveolares que presentan un defecto volumétrico que dificultan la inserción de un implante dental en la posición tridimensionalmente correcta. Existen diferentes técnicas quirúrgicas de aumento óseo, entre ellas están los injertos en bloque o Split Bone Bloque Technique (SBBT). Esta técnica combina laminas corticales y hueso particulado de origen autólogo, logrando una integración más rápida del injerto. El objetivo de ese caso es describir el manejo y abordaje clínico de un defecto de alto compromiso estético y complicación quirúrgico-protésica mediante colgajo rotado de paladar, SBBT y posterior provisionalización de un implante dental osteointegrado. Caso clínico: Varón de 54 años que acude a la Clínica Universitaria de la Universidad Rey Juan Carlos con una dehiscencia del tejido blando que sobrepasaba la línea mucoginvival a nivel del incisivo 1.1 cursando con movilidad del fragmento vestibular El paciente no refería sintomatología ni signos patológicos. Se estableció como plan de tratamiento la extracción del diente y aumento del tejido blando mediante la técnica de colgajo rotado de paladar a pedículo posterior. Y posteriormente se realizó la regeneración ósea horizontal mediante SBBT. Conclusión: La regeneración ósea mediante SBBT es una técnica predecible con altas tasas de éxito tanto horizontal como vertical. Asociado a la regeneración, el manejo del tejido blando con colgajos o injertos de tejido conectivo permite obtener el volumen deseado. (AU)

Introduction: There are bone alterations in the alveolar crests that present a volumetric defect that makes inserting a dental implant in the correct threedimensional position difficult. There are different surgical techniques for bone augmentation, including block grafts or the Split Bone Block Technique (SBBT). This technique combines cortical laminas and particulate bone of autologous origin, thus achieving a faster integration of the graft. The aim of this case is to describe the management and clinical approach of a defect with high aesthetic compromise and surgical-prosthetic complication by means of a rotated palatal flap, SBBT and subsequent provisionalization of an osseointegrated dental implant. Case study: A 54 year old man attended the University Clinic of the Rey Juan Carlos University with a dehiscence of the soft tissue that went beyond the mucoginvival line at the level of incisor 1.1 with mobility of the vestibular fragment. The patient did not report any symptoms or pathological signs. Tooth removal and soft tissue augmentation using the rotated palatal to posterior pedicle flap technique were established as a treatment plan. Horizontal bone regeneration was then performed using SBBT. Conclusion: Bone regeneration using SBBT is a predictable technique with high success rates both horizontally and vertically. Associated with regeneration, soft tissue management with flaps or connective tissue grafts makes it possible to achieve the desired volume. (AU)

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.