Long-Term Safety of Bone Regeneration Using Autologous Stromal Vascular Fraction and Calcium Phosphate Ceramics: A 10-Year Prospective Cohort Study.

This prospective cohort study aimed to assess long-term safety, dental implant survival, and clinical and radiological outcomes after maxillary sinus floor elevation (MSFE; lateral window technique) using freshly isolated autologous stromal vascular fraction (SVF) combined with calcium phosphate ceramics. All 10 patients previously participating in a phase I trial were included in a 10-year follow-up. They received either ß-tricalcium phosphate (ß-TCP; n = 5) or biphasic calcium phosphate (BCP; n = 5) with SVF-supplementation on one side (study). Bilaterally treated patients (6 of 10; 3 ß-TCP, 3 BCP) received only calcium phosphate on the opposite side (control). Clinical and radiological assessments were performed on 44 dental implants at 1-month pre-MSFE, and 0.5- to 10-year post-MSFE. Implants were placed 6 months post-MSFE. No adverse events or pathology was reported during a 10-year follow-up. Forty-three dental implants (98%) remained functional. Control and study sides showed similar peri-implant soft-tissue quality, sulcus bleeding index, probing depth, plaque index, keratinized mucosa width, as well as marginal bone loss (0-6 mm), graft height loss (0-6 mm), and graft volume reduction. Peri-implantitis was observed around 6 implants (control: 4; study: 2) in 3 patients. This study is the first to demonstrate the 10-year safety of SVF-supplementation in MSFE for jawbone reconstruction. SVF-supplementation showed enhanced bone regeneration in the short term (previous study) and led to no abnormalities clinically and radiologically in the long term.

Effects of Bone Grafting and Non-Bone Grafting on Implant Stability and New Bone Formation in Patients Undergoing Maxillary Sinus Floor Elevation Combined with Bicon Short Implants.

Objective: To compare the effects of bone grafting versus non-bone grafting on implant stability and new bone formation in patients undergoing maxillary sinus floor lift combined with placement of a Bicon short dental implant. Methods: We recruited 60 patients with posterior maxillary tooth loss and insufficient jaw bone mass from December 2017 to December 2019, and the patients were divided into 2 groups in accordance with the surgical method: the bone grafted group (n = 32) and the non-bone grafted group (n = 28). Both groups underwent maxillary sinus floor elevation combined with Bicon short dental implant placement. No bone-grafting materials were used in the non-bone grafted group, and autologous bone chips mixed with Bicon bone substitute were used for bone grafting in the bone grafted group. The 2 groups were compared for their peri-implant index and periodontal bleeding index immediately after the operation, as well as at 3, 6, and 12 months postoperatively. The study also compared the sub-sinus-membrane height, peri-implant bone density, implant stability quotient, and alveolar bone height in the implant area at 3, 6, and 12 months after the operation, as well as the implant survival rate and complications (infection, bleeding, mucosal perforation, sinus-floor cyst, and bone-graft displacement) 12 months after the operation. Results: The peri-implant index and periodontal bleeding index immediately after the operation in the bone grafted group were higher than those in the non-bone grafted group (all P < .05), but there were no significant differences in the 2 indices between the 2 groups at 3, 6, and 12 months after the operation (all P > .05). The sub-sinus-membrane height, peri-implant bone density, implant stability quotient, and alveolar bone height in the bone grafted area were higher in the bone grafted group than in the non-bone grafted group at 3, 6, and 12 months after the operation (all P < .05). Although the implant survival rate in the bone grafted group was slightly higher than that in the non-bone grafted group at 12 months after the operation, the difference was not statistically significant (P > .05). One case of mucosal perforation occurred in the bone grafted group, but there was no significant difference in the complication rate between the 2 groups (P > .05). Conclusion: The findings of this study support the use of autologous bone chips mixed with Bicon bone substitute in maxillary sinus floor elevation combined with Bicon short dental implant placement for improved implant stability and new bone formation. Further research is needed to evaluate long-term outcomes and potential complications associated with this technique.

Radiographic outcome after maxillary sinus floor augmentation with allogeneic adipose tissue-derived stem cells seeded on deproteinized bovine bone mineral. A randomized controlled experimental study.

The objective was to test the hypothesis of no difference in radiographic outcome after maxillary sinus floor augmentation (MSFA) with allogeneic adipose tissue-derived stem cells (ASCs) seeded on deproteinized bovine bone mineral (DBBM) (test) compared with excipient on DBBM (control). Eighteen minipigs were assigned into three groups of six animals and euthanised after one month (T1), two months (T2), and four months (T3), respectively. Each maxillary sinus was randomly allocated to either test or control with an equal volume of graft. Computed tomography scans (CTs) after MSFA (T0) were compared with CTs after euthanasia to evaluate graft volume (GV) changes and bone density (BD) using three-dimensional measurements and Hounsfield units. GV was larger in test compared with control at T1 (P = 0.046), whereas GV was larger in control compared with test at T3 (P = 0.01). BD increased from T0 to T1-T3 (P < 0.001) with both treatments. Higher BD was observed in control compared with test at T3 (P = 0.01), while no significant difference was observed at T1 and T2. Conclusively, the present study demonstrate that allogeneic ASCs seeded on DBBM in conjunction with MSFA seemed not to improve the radiographic outcome compared with excipient on DBBM. However, radiological outcomes need to be supplemented by bone histomorphometry before definitive conclusions can be provided about the beneficial use of allogeneic ASCs seeded on DBBM in conjunction with MSFA compared with DBBM alone.

Bone Formed After Maxillary Sinus Floor Augmentation by Bone Autografting With Hydroxyapatite and Low-Level Laser Therapy: A Randomized Controlled Trial With Histomorphometrical and Immunohistochemical Analyses.

PURPOSE: The aim of this study was to evaluate the bone formed after maxillary sinus floor augmentation (MSFA) by bone autografting combined with hydroxyapatite (HA) that had been either treated with low-level laser therapy (LLLT) or not. MATERIALS AND METHODS: Twelve biopsies were obtained from patients 6 months after MSFA using a combination of 50% of autogenous bone (AB) and 50% of HA (AB/HA group, n = 6) followed by LLLT (AB/HA-LLLT group, n = 6). The laser used in this study was gallium-aluminium-arsenide laser with a wavelength of 830 nm (40 mW; 5.32 J/point; 0.57 W/cm). Samples obtained were subjected to histological, histometric, and immunohistochemical analysis for detection of tartrate-resistant acid phosphatase and runt-related transcription factor 2. The data were submitted to statistical analysis (Shapiro-Wilk and Student t tests; α = 5%). RESULTS: Statistical analysis revealed no significant difference in vital bone presence and immunohistochemical analysis between the groups. There was no reduction in bone marrow or fibrous tissue in the AB/HA group and AB/HA-LLLT group. There was a decrease in the amount of remaining biomaterial between the groups (P = 0.0081). CONCLUSION: LLLT did not increase the formation of new bone; instead, it accelerated the bone remodeling process.

In-vitro and in-vivo design and validation of an injectable polysaccharide-hydroxyapatite composite material for sinus floor augmentation.

OBJECTIVE: Polysaccharide-based composite matrices consisting of natural polysaccharides, pullulan and dextran supplemented with hydroxyapatite (Matrix-HA) have recently been developed. The principal objective of this study was to evaluate the capacities of this composite material to promote new bone formation in a sinus lift model in the sheep. Secondary objectives were to evaluate in vitro properties of the material regarding cell adhesion and proliferation. METHODS: In this report, once such composite matrix was prepared as injectable beads after dispersion in a physiological buffer, and evaluated using a large animal model (sheep) for a sinus lift procedure. RESULTS: In vitro studies revealed that these microbeads (250-550µm in diameter) allow vascular cell adhesion and proliferation of Endothelial Cells (EC) after 1 and 7 days of culture. In vivo studies were performed in 12 adult sheep, and newly formed tissue was analyzed by Cone Beam Computed Tomography (CBCT scanning electron microscopy (SEM) and by histology 3 and 6 months post-implantation. CBCT analyses at the implantation time revealed the radiolucent properties of these matrices. Quantitative analysis showed an increase of a dense mineralized tissue in the Matrix-HA group up to 3 months of implantation. The mineralized volume over total volume after 6 months reached comparable values to those obtained for Bio-Oss® used as positive control. Histological examination confirmed that the Matrix-HA did not induce any long term inflammatory events, and promoted direct contact between the osteoid tissue and lamellar bone structures and beads. After 6 months, we observed a dense network of osteocytes surrounding both biomaterials as well as a newly vascularized formed tissue in close contact to the biomaterials. SIGNIFICANCE: In conclusion, the absence of animal components in Matrix-HA, the osteoconductive property of Matrix-HA in sheep, resulting in a dense bone and vascularized tissue, and the initial radiolucent property to follow graft integration offer great promises of this composite material for clinical use.

Regenerative potential of leucocyte- and platelet-rich fibrin. Part B: sinus floor elevation, alveolar ridge preservation and implant therapy. A systematic review.

AIM: To analyse the effect of leucocyte- and platelet-rich fibrin (L-PRF) on bone regeneration procedures and osseointegration. MATERIALS AND METHODS: An electronic and hand search was conducted in three databases (MEDLINE, EMBASE and Cochrane). Only randomized clinical trials, written in English where L-PRF was applied in bone regeneration and implant procedures, were selected. No follow-up restrictions were applied. RESULTS: A total of 14 articles were included and processed. Three subgroups were created depending on the application: sinus floor elevation (SFE), alveolar ridge preservation and implant therapy. In SFE, for a lateral window as well as for the trans-alveolar technique, histologically faster bone healing was reported when L-PRF was added to most common xenografts. L-PRF alone improved the preservation of the alveolar width, resulting in less buccal bone resorption compared to natural healing. In implant therapy, better implant stability over time and less marginal bone loss were observed when L-PRF was applied. Meta-analyses could not be performed due to the heterogeneity of the data. CONCLUSIONS: Despite the lack of strong evidence found in this systematic review, L-PRF might have a positive effect on bone regeneration and osseointegration.

Manejo de tejidos blandos en regeneración/reconstrucción ósea mediante la técnica quirúrgica ‘Double Flap Incision Technique modificada’. Técnica de preservación del periostio / Oral surgery management of soft tissues with a new ‘Double Flap Incision Technique’ A periosteal preservation technique

Introducción: Las técnicas implantológicas demandan la existencia de unas estructuras óseas adecuadas en calidad y cantidad para alojar las fijaciones oseointegradas de un modo predecible. En ocasiones, el sustrato óseo es insuficiente, por lo que son necesarias técnicas de reconstrucción/regeneración ósea que precisan de un cierre primario completo para asegurarnos que los fenómenos que conducirán a la formación de nuevo tejido óseo se sucedan. El objetivo de este estudio es mostrar una serie de ocho casos clínicos donde la ‘Double Flap Incision Technique modificada’ nos sirve para reconstruir zonas de defecto óseo en la región mandibular posterior que limitaban la colocación de fijaciones oseointegradas. Métodos: Se realiza un estudio prospectivo de ocho casos clínicos procedentes de nuestra práctica privada, con déficit óseo en la zona posterior mandibular en pacientes demandantes de un tratamiento rehabilitador con prótesis fija implantosoportada. En todos los casos se utilizó la denominada ‘Double Flap Incision Technique modificada’ (DFITm). Resultados: En todos los casos conseguimos un cierre primario completo a los 15 días y fue posible la colocación de los implantes en la zona regenerada con criterio protésicamente guiado. Conclusión: La técnica de doble colgajo ‘Double Flap Incision Technique modificada’ nos permite llevar a cabo un adecuado cierre primario sin tensión en casos que requieran una reconstrucción o regeneración ósea, evitando la aparición de dehiscencias que conllevarían al fracaso del tratamiento (AU)

Introduction: Dental implants’ techniques needed to appropiate high-quality bones structures which can support osteointegration bindings in a predictable way. Occasionally, bone substrate is not the suitable one, it is for that reason that we need bone reconstruction and regeneration techniques in which we have to make a complete wound healing in order to guarantee bone regeneration in a correct way. The aim of this article is to comment eight case reports in which we used ‘Double flap incision technique’ to repair bone loss in posterior mandibular region. Methods: We have carried out a pilot study in about eight cases reports whose patients had bone loss in posterior mandibular region and treated with a dental implants’ repair treatment. ‘New Double Flap Incision Technique’ was used in all the cases we report. Results: We obtained an appropiate and complete wound healing in 15 days. In addition, dental implants were positionated in regenerated region correctly in all cases. Conclusion: This ‘New Double Flap Incision Technique’ provide us a way to obtain complete wound healing with no strain in cases which needed bone regeneration or reconstruction, avoid the presence of dehiscences which fail the treatment (AU)

Bone Regeneration Using the Freshly Isolated Autologous Stromal Vascular Fraction of Adipose Tissue in Combination With Calcium Phosphate Ceramics.

: In patients undergoing maxillary sinus floor elevation (MSFE) for dental implant placement, bone substitutes are currently evaluated as alternatives for autologous bone. However, bone substitutes have only osteoconductive properties and lack osteoinductive potential. Therefore, this phase I study evaluated the potential additive effect on bone regeneration by the addition of freshly isolated, autologous but heterologous stromal vascular fraction (SVF), which is highly enriched with adipose stromal/stem cells when compared with native adipose tissue. From 10 patients, SVF was procured using automatic processing, seeded on either ß-tricalcium phosphate (n = 5) or biphasic calcium phosphate carriers (n = 5), and used for MSFE in a one-step surgical procedure. Primary objectives were feasibility and safety. The secondary objective was efficacy, evaluated by using biopsies of the augmented area taken 6 months postoperatively, concomitant with dental implant placement. Biopsies were assessed for bone, graft, and osteoid volumes. No adverse effects were reported during the procedure or follow-up (≥3 years). Bone and osteoid percentages were higher in study biopsies (SVF supplemented) than in control biopsies (ceramic only on contralateral side), in particular in ß-tricalcium phosphate-treated patients. Paired analysis on the six bilaterally treated patients revealed markedly higher bone and osteoid volumes using microcomputed tomography or histomorphometric evaluations, demonstrating an additive effect of SVF supplementation, independent of the bone substitute. This study demonstrated for the first time the feasibility, safety, and potential efficacy of SVF seeded on bone substitutes for MSFE, providing the first step toward a novel treatment concept that might offer broad potential for SVF-based regenerative medicine applications. SIGNIFICANCE: This is the first-in-human study using freshly isolated, autologous adipose stem cell preparations (the stromal vascular fraction [SVF] of adipose tissue) applied in a one-step surgical procedure with calcium phosphate ceramics (CaP) to increase maxillary bone height for dental implantations. All 10 patients received CaP plus SVF on one side, whereas bilaterally treated patients (6 of 10) received CaP only on the opposite side. This allowed intrapatient evaluation of the potential added value of SVF supplementation, assessed in biopsies obtained after 6 months. Feasibility, safety, and potential efficacy of SVF for bone regeneration were demonstrated, showing high potential for this novel concept.

Hyaluronic Acid Versus Ultrasonic Resorbable Pin Fixation for Space Maintenance in Non-Grafted Sinus Lifting.

PURPOSE: An ultrasonic resorbable pin (SonicWeld, KLS Martin, Mühlheim, Germany) was compared with hyaluronic acid (Hyaloss Matrix, Anika Therapeutics, Bedford, MA) for their ability to maintain space in non-grafted sinus lifting. MATERIALS AND METHODS: A comparative split-mouth study was designed and implemented. Six women and 4 men were included (mean age, 56.7 yr). The primary predictors hyaluronic acid (HA) application and ultrasonic resorbable pin fixation (URPF) were coded as binary variables. The primary outcome variables were height of alveolar bone (HAB) and reduction in sinus volume (RSV). Secondary outcomes were bone density and implant survival. RESULTS: The postoperative mean HAB was significantly higher than the preoperative mean HAB on the 2 sides (P < .05). Mean increases in HAB and RSV on the URPF side were significantly greater than those on the HA side (P < .05). In total, patients were treated with 40 implants. No type I bone quality was identified; 14 (35%) implants were inserted in type II bone, 22 (50%) in type III bone, and 6 (15%) in type IV bone. There was no statistically meaningful difference between the 2 sides for implant survival or bone quality. At 6 months, all implants were clinically stable and the definitive prostheses were functional, resulting in a survival rate of 100%. CONCLUSIONS: There was sufficient bone height to eventually place implants on the 2 sides in all patients. The 2 techniques yielded predictable outcomes in implant survival and bone quality. However, HAB and RSV were considerably greater on the URPF side.

Experimental evaluation of the effects of Ankaferd Blood Stopper and collagenated heterologous bone graft on bone healing in sinus floor augmentation.

PURPOSE: The aim of this study was to evaluate the effect of collagenated heterologous bone graft (CHBG) and Ankaferd Blood Stopper (ABS), a plant extract, on bone healing after sinus floor augmentation. MATERIALS AND METHODS: Thirty-six New Zealand rabbits were used. Bilateral sinus augmentation was performed, and 72 bone defects were created. The maxillary sinuses were grafted with four different biomaterials: blood clot (control group), CHBG (Apatos Mix, OsteoBiol, Tecnoss) (graft group), ABS (ABS group), and ABS + CHBG (ABS+graft group). The rabbits were sacrificed at 1, 4, and 8 weeks after surgery. Histochemical and immunohistochemical examinations were performed on all samples. Staining with hematoxylin-eosin and Masson trichrome was performed, and bone marker activity was evaluated. RESULTS: Lymphocyte infiltration was high at the first week in all groups and decreased from 1 to 8 weeks. All materials were biocompatible. Osteoclast numbers increased in the control group from 1 to 8 weeks and decreased in the other groups. There was no new bone formation in week 1 in all groups. New bone formation increased in all groups from 1 to 8 weeks, and at the fourth week, new bone formation was greater in the ABS and ABS+graft groups than in the other groups. There were osteoclasts around the bone graft materials, but degeneration of the graft was seen only in the ABS+graft group at week 8. CONCLUSION: ABS accelerates bone healing in sinus augmentation procedures and can be used alone or with CHBG. CHBG has osteoconductive properties, and ABS can accelerate bone graft degeneration.

Pre-clinical evaluation of the osteogenic potential of bone morphogenetic protein-2 loaded onto a particulate porcine bone biomaterial.

AIM: The objective of study was to determine the osteogenic potential of bone morphogenetic protein-2 (BMP-2) loaded onto a particulate porcine bone mineral (PBM) biomaterial using a sinus augmentation model. METHODS: Release kinetics of BMP-2/PBM was determined in vitro. Eight rabbits received BMP-2/PBM or PBM alone into contra-lateral sinus sites. The animals were killed following a 2-week healing interval for micro-CT and histometrical analysis. RESULTS: Approximately 40% of the BMP-2 was released from PBM over the first 3 days in vitro; release maintained at a reduced level through day 21. In vivo, total augmented implant volume did not differ significantly between treatments. However, local bone formation was enhanced in the BMP-2/PBM group compared with PBM control (10.5% versus 6.6%; p = 0.03), specifically in the central aspect of the PBM implant (14.2% versus 5.5%; p < 0.01) and adjoining the Schneiderian membrane (11.9% versus 5.0%; p < 0.05). There were no significant overall differences in residual biomaterial and fibrovascular tissue. CONCLUSION: Bone morphogenetic protein-2 enhanced local bone formation in the rabbit maxillary sinus model following implantation using a PBM carrier.

Highly porous hydroxyapatite with and without local harvested bone in sinus floor augmentation: a histometric study in pigs.

OBJECTIVE: Sinus floor augmentation with autologous bone is an accepted treatment option in dental implantology. In this study, an entirely synthetic, nano-structured, hydroxyapatite-based bone substitute material (SBSM, NanoBone(®); Artoss, Rostock, Germany) was supplemented with a mixture of locally harvested bone to enhance osteogenesis. METHODS: Bilateral sinus augmentation procedures were performed in eight domestic pigs using the lateral window technique. On the right side (control), 2.6 ml of SBSM was used, and on the left side (test), 2.6 ml of SBSM with additional 15% (390 µl) autologous bone was used. At the time of augmentation, a titanium implant (ITI(®)) was inserted from a laterocaudal direction. After 3 months, the sites of augmentation were removed and examined in non-decalcified sections by microradiography and fluorescence microscopy of sequentially labelled specimens and histometry. RESULTS: On both sides, a significant amount of newly formed bone was observed. However, a statistically significant difference in the bone-implant contact was observed in the control group (median, 28.9%) compared with the test side with the additional autologous bone (median, 40.6%) (P = 0.01). Different bone density was achieved from the coronal to apical surfaces (medians, 54.6%, 9.6%, and 27.5%) compared with the test side (medians, 55.2%, 40.6%, and 44.2%). The median of augmentation height was 8.6 mm on the control side and 11.5 mm on the test side (P = 0.01). Bone apposition was observed in both groups after 15 days. CONCLUSION: The SBSM shows acceptable results in sinus floor augmentation. The additional use of locally harvested autologous bone enhances bone density and osseointegration of the implants.

Use of 3D cartilage scaffolds for the stabilization of implants and bone regeneration with the fit-lock technique

Los procedimientos quirúrgicos para la aplicación de los implantes en los sectores latero superiores, están condicionadas por la neumatización del seno y la disponibilidad del huesoresidual. En estos casos el injerto de hueso autólogo permanece como lamejor opción, pero a causa de la morbilidad asociada al sitio donante y a las complicaciones post quirúrgicas, se pusieron a disposición diversas alternativas de sustitutos óseos, que implican sin embargo un aumento de los costos económicos y con limitadas propiedades osteoinductivas. Tales defectos pueden ser compensados con nuevas estrategias de regeneración biológica y mecánica de los tejidos a loscuales fue dirigida la ingeniería biológica y mecánica en los últimos años.Se presenta una nueva posibilidad terapéutica en la aplicación de los implantes en el maxilar superior con disponibilidad ósea inferior a los 4 mm, mediante la utilización de andamios 3D confeccionados en cartilago de cerdo libre de antígenos obtenido según la tecnica Fit-Lock. Se realizo un estudio longitudinal en 18 casos consecutivosevidenciando al cabo de un año de la carga implantológica, un éxito del 95,2 por ciento. Las ventajas en esta nueva técnica son: 1)La recuperación funcionaly anatómica del antro del maxilar 2).La aplicación inmediata de los implantes; 3)Reducción de los tiempos quirúrgicos; 4) Ausencia de morbilidad para el paciente; 5) Uso de anestesia local; 6)Uso de implantes con diámetros superiores a los 4 mm

Radiographic evaluation of regenerated bone following poly(lactic-co-glycolic) acid/hydroxyapatite and deproteinized bovine bone graft in sinus lifting.

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.

Osteotome maxillary sinus lift using bovine bone and calcium sulfate: a case series.

PURPOSE: The purpose of this longitudinal study was to evaluate the success of bovine bone and calcium sulfate (CaSO(4)) as sinus augmentation material with osteotome maxillary sinus lift. MATERIALS AND METHODS: Thirty-one osteotome sinus lift procedures were performed for 18 healthy patients (7 males and 11 females). A mixture of bovine bone and CaSO(4) (ratio, 4:1) was used as sinus augmentation material with simultaneous implant placement. Implants were loaded 4 to 5 months postimplant surgery. Cases were followed for an average of 23.4 months postloading (range, 12-60 months). RESULTS: The mean age of the study group was 49.7 ± 10.66 years. The residual height of the alveolar ridge ranged from 5.5 to 11 mm (mean, 8.16 ± 1.52 mm). Four to 5 months after implant placement, the x-ray showed a 1.5 to 5 mm apical shift of the sinus floor (mean, 3.47 ± 0.97 mm), which was maintained to the end of the evaluation period. At 12 months postloading, crestal bone loss ranged from 0.5 to 1.5 mm (mean, 0.87 ± 0.26 mm), and pocket depth ranged from 2 to 4 mm (mean, 2.9 ± 0.67 mm). No significant change in crestal bone loss or pocket depth was noticed afterward. CONCLUSION: Bovine bone plus CaSO(4) can be used successfully as a sinus augmentation material with osteotome sinus elevation. The use of CaSO(4) significantly improved the handling properties of bovine bone and helped to stabilize the bone graft particles during healing.

Socket preservation and sinus augmentation using a medical grade calcium sulfate hemihydrate and mineralized irradiated cancellous bone allograft composite.

Regeneration and preservation of bone after the extraction of a tooth are necessary for the placement of a dental implant. The goal is to regenerate alveolar bone with minimal postoperative pain. Medical grade calcium sulfate hemihydrate (MGCSH) can be used alone or in combination with other bone grafts; it improves graft handling characteristics and particle containment of particle-based bone grafts. In this case series, a 1:1 ratio mix of MGCSH and mineralized irradiated cancellous bone allograft (MICBA) was mixed with saline and grafted into an extraction socket in an effort to maintain alveolar height and width for future implant placement. MGCSH can be used in combination with other bone grafts and can improve handling characteristics and graft particle containment of particle-based bone grafts. In the cases described, we found that an MGCSH:MICBA graft can potentially be an effective bone graft composite. It has the ability to act as a space maintainer and as an osteoconductive trellis for bone cells, thereby promoting bone regeneration in the extraction socket. MGCSH, a cost-effective option, successfully improved MICBA handling characteristics, prevented soft tissue ingrowth, and assisted in the regeneration of bone.

Use of 3D cartilage scaffolds for the stabilization of implants and bone regeneration with the fit-lock technique.

The surgical procedures for implant applications on the lateral-upper areas depend on sinus pneumatization and availability of the residual bone. In these cases, autologous bone grafting remains the gold standard. Nevertheless, because of the morbidity associated to the donor site and the post-surgical complications, several alternative bone substitutes have been introduced, which, however, imply additional costs and show limited osteoinductive properties. Such limitations can be compensated with new regeneration strategies for biological and mechanical tissue restoration, a subject which has been addressed by tissue engineering in recent years. The authors present a new therapeutic option for implant application in the upper maxilla with bone availability less than 4 mm by using 3D scaffolds obtained from antigen-free porcine cartilage in the fit-lock technique. A longitudinal study on 18 consecutive cases was performed, with a 95.2% success rate one year after the implant. The advantages of this new technique are: 1) Functional and anatomical recovery of the maxillary antrum, 2) Immediate application of the implants; 3) Reduction of surgical times; 4) Absence of patient morbidity; 5) Local anesthesia; 6) Use of implants with a diameter > 4 mm.

Use of 3D cartilage scaffolds for the stabilization of implants and bone regeneration with the fit-lock technique. / Use of 3D cartilage scaffolds for the stabilization of implants and bone regeneration with the fit-lock technique.

The surgical procedures for implant applications on the lateral-upper areas depend on sinus pneumatization and availability of the residual bone. In these cases, autologous bone grafting remains the gold standard. Nevertheless, because of the morbidity associated to the donor site and the post-surgical complications, several alternative bone substitutes have been introduced, which, however, imply additional costs and show limited osteoinductive properties. Such limitations can be compensated with new regeneration strategies for biological and mechanical tissue restoration, a subject which has been addressed by tissue engineering in recent years. The authors present a new therapeutic option for implant application in the upper maxilla with bone availability less than 4 mm by using 3D scaffolds obtained from antigen-free porcine cartilage in the fit-lock technique. A longitudinal study on 18 consecutive cases was performed, with a 95.2

success rate one year after the implant. The advantages of this new technique are: 1) Functional and anatomical recovery of the maxillary antrum, 2) Immediate application of the implants; 3) Reduction of surgical times; 4) Absence of patient morbidity; 5) Local anesthesia; 6) Use of implants with a diameter > 4 mm.

Histologic and histomorphometric results of three bone graft substitutes after sinus augmentation in humans.

The aim of this study was to compare the histological behavior of three bone graft materials placed in human. The comparison was made among Bio-Oss® (BO), Engipore® (EP), and PepGen P-15® (P-15). Five biopsies for each group of biomaterial, retrieved 6 months after sinus lift augmentation, were analyzed. The investigation was carried out using light microscope (LM), scanning electron microscope (SEM) with an energy dispersive spectrometer (EDS), and circularly polarized light microscope (CPLM). Under LM, the amount of newly formed bone was significantly higher in BO than P-15 (P < .05), while the amount of residual graft material was significantly higher in P-15 than BO (P < .05). The extension of marrow spaces was significantly higher in EP than both BO and P-15 (P < .05). SEM-EDS analysis showed a Ca/P ratio of 1.8 for BO, 2.2 for EP, and 1.5 for P-15. Under CPLM, BO showed no significant difference for transverse (18.4 ± 2.7%) and longitudinal (16.3 ± 1.8%) bone collagen fibers (P = .195); EP showed a significant difference between transverse (4 ± 0.7%) and longitudinal (7.6 ± 2.5%) bone collagen fibers (P = .015); finally, P-15 showed no significant difference for transverse (3.8 ± 1.6%) and longitudinal (4.9 ± 1.2%) bone collagen fibers (P = .279). No investigated biomaterial was completely resorbed, but all the residual particles demonstrated a close bone integration to form a hybrid tissue. BO particles appeared perfectly osseointegrated in the trabecular bone. EP showed a tendency to concentrate the bone apposition into the microporosities; P-15 particles appeared bridged by newly formed bone trabeculae.

A clinical and histological case series study on calcium sulfate for maxillary sinus floor augmentation and delayed placement of dental implants.

BACKGROUND: Maxillary sinus floor augmentation is a procedure that is indicated in cases when the volume of the posterior maxillary bone is inadequate. The goal of this treatment is to obtain sufficient amount of bone tissue in order to gain osseointegration of endosseous implants. PURPOSE: The purpose of this study was to conduct a clinical and histological analysis of calcium sulfate (CaS) as bone graft substitute in sinus floor augmentation. MATERIAL AND METHODS: Ten patients with edentulous maxillas were included in this study. They had moderate to severe atrophy of the posterior maxilla. Surgiplaster (Classimplant®, Rome, Italy) was used as graft material in the maxillary sinus and was covered by BioGide® (Geistlish Pharmaceutical, Wolhusen, Switzerland). After 4 months of graft healing, 40 dental implants were placed and a biopsy for histomorphometry was taken at these occasions. The specimens were viewed by light microscope, and the extent of bone regeneration and remaining graft material was evaluated. Radiographs were taken at the time of sinus augmentation and after 4 months of graft healing. RESULTS: At the time of abutment surgery, one implant was considered as a failure and was consequently removed, giving a survival rate of 97.5% after 1 year of loading. Radiographs showed a mean of 26.5% shrinkage of the augmented area. A significant resorption of CaS was noted with a mean value of 8.8% of remaining graft material after 4 months of healing. The biopsies also revealed new bone formation with a mean value of 21.2% of the total biopsy area. Histology showed signs of an acellular substitution of CaS with bone-like tissue. CONCLUSION: The results of this study show that new bone regeneration occurs in the maxillary sinus after augmentation with CaS. This enabled successful placement, integration, and loading of dental implants in the posterior maxilla, as only 1 of 40 implants was lost during 1 year of follow-up.