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This study was designed to assess the effect of enamel matrix derivative (Emdogain, Straumann) and alloplastic bone substitute (BoneCeramic, Straumann) on new bone formation in postextraction alveolar sockets. Twenty-one patients requiring anterior single-tooth extractions and subsequent implant placement were recruited and randomly assigned to one of three treatment groups. Postextraction sockets were filled with either an alloplastic bone substitute (BoneCeramic [BC]), BC combined with Emdogain (EMD+BC), or left to heal spontaneously (SO). Histologic and histomorphometric analyses of the results were performed at 6 months postextraction. A significant increase in the percentage of new bone tissue area was found in EMD+BC compared to SO and BC groups. These findings demonstrate that compared with BC or SO, EMD+BC allowed for better formation of new bone in postextraction sockets after 6 months of healing. [ABSTRACT FROM AUTHOR]

Bone defects have prompted the development of biomaterial-based bone substitutes for restoring the affected tissue completely. Although many biomaterials have been designed and evaluated, the combination of properties required in a biomaterial for bone tissue engineering still poses a challenge. In this study, a chitosan–silica-based biocomposite was synthetized, and its physicochemical characteristics and biocompatibility were characterized, with the aim of exploring the advantages and drawbacks of its use in bone tissue engineering. Dynamic light scattering measurements showed that the mean hydrodynamic size of solid silica particles (Sol-Si) was 482 ± 3 nm. Scanning electron microscopy of the biocomposite showed that Sol-Si were homogenously distributed within the chitosan (CS) matrix. The biocomposite swelled rapidly and was observed to have no cytotoxic effect on the [3T3] cell line within 24 h. Biocompatibility was also analyzed in vivo 14 days post-implant using a murine experimental model (Wistar rats). The biocomposite was implanted in the medullary compartment of both tibiae (n = 12). Histologically, no acute inflammatory infiltrate or multinucleated giant cells associated to the biocomposite were observed, indicating good biocompatibility. At the tissue–biocomposite interface, there was new formation of woven bone tissue in close contact with the biocomposite surface (osseointegration). The new bone formation may be attributed to the action of silica. Free silica particles originating from the biocomposite were observed at the tissue–biocomposite interface. According to our results, the biocomposite may act as a template for cellular interactions and extracellular matrix formation, providing a structural support for new bone tissue formation. The CS/Sol-Si biocomposite may act as a Si reservoir, promoting new bone formation. A scaffold with these properties is essential for cell differentiation and filling a bone defect. [ABSTRACT FROM AUTHOR]

Implant therapy using osseointegratable titanium (Ti) dental implants has revolutionized clinical dental practice and has shown a high rate of success. However, because a metallic implant is in contact with body tissues and fluids in vivo, ions/particles can be released into the biological milieu as a result of corrosion or biotribocorrosion. Ultrananocrystalline diamond (UNCD) coatings possess a synergistic combination of mechanical, tribological, and chemical properties, which makes UNCD highly biocompatible. In addition, because the UNCD coating is made of carbon (C), a component of human DNA, cells, and molecules, it is potentially a highly biocompatible coating for medical implant devices. The aim of the present research was to evaluate tissue response to UNCD-coated titanium micro-implants using a murine model designed to evaluate biocompatibility. Non-coated (n = 10) and UNCD-coated (n = 10) orthodontic Ti micro-implants were placed in the hematopoietic bone marrow of the tibia of male Wistar rats. The animals were euthanized 30 days post implantation. The tibiae were resected, and ground histologic sections were obtained and stained with toluidine blue. Histologically, both groups showed lamellar bone tissue in contact with the implants (osseointegration). No inflammatory or multinucleated giant cells were observed. Histomorphometric evaluation showed no statistically significant differences in the percentage of BIC between groups (C: 53.40 ± 13% vs. UNCD: 58.82 ± 9%, p > 0.05). UNCD showed good biocompatibility properties. Although the percentage of BIC (osseointegration) was similar in UNCD-coated and control Ti micro-implants, the documented tribological properties of UNCD make it a superior implant coating material. Given the current surge in the use of nano-coatings, nanofilms, and nanostructured surfaces to enhance the biocompatibility of biomedical implants, the results of the present study contribute valuable data for the manufacture of UNCD coatings as a new generation of superior dental implants. [ABSTRACT FROM AUTHOR]

Bone is a hierarchical material that has inspired the design of biopolymer‐derived biocomposites for tissue engineering purposes. The present study sought to synthesize and perform the physicochemical characterization and biocompatibility of a collagen‐silica‐based biocomposite for potential application in bone tissue engineering. Ultrastructure, biodegradability, swelling behavior, and biocompatibility properties were analyzed to gain insight into the advantages and limitations to the use of this biomaterial as a bone substitute. Scanning electron microscopy analysis showed a packed‐collagen fibril matrix and silica particles in the biocomposite three‐dimensional structure. As shown by analysis of in vitro swelling behavior and biodegradability, it would seem that the material swelled soon after implantation and then suffered degradation. Biocompatibility properties were analyzed in vivo 14‐days postimplantation using an experimental model in Wistar rats. The biocomposite was placed inside the hematopoietic bone marrow compartment of both tibiae (n = 16). Newly formed woven bone was observed in response to both materials. Unlike the pure‐collagen‐tissue interface, extensive areas of osseointegration were observed at the biocomposite‐tissue interface, which would indicate that silica particles stimulated new bone formation. Agglomerates of finely particulate material with no inflammatory infiltrate or multinucleated giant cells were observed in the bone marrow implanted with the biocomposite. The biocomposite showed good biocompatibility properties. Further studies are necessary to evaluate their biological behavior over time. [ABSTRACT FROM AUTHOR]

Study of the implant-tissue interface is one of the fundamental issues in implantology, both odontologic and orthopedic. The characteristics of this interface will influence the success or failure of an implant. The aim of the present study was to evaluate histomorphometrically the capacity of different metals to osseointegrate employing laminar implants of zirconium, titanium, aluminum, and zirconium coated with diamond-like carbon. The experimental model herein allowed for the quantitative evaluation of the tissue-implant interface for different metals. The implants were placed in the tibiae of Wistar rats under anesthesia and allowed to remain in situ for a 30-day period. The interfaces of the zirconium and diamond-like coated zirconium implants exhibited better responses than the interface of titanium implants. Aluminum produced a local toxic effect, evidenced by osteoid formation. [ABSTRACT FROM AUTHOR]

High density polyethylene (HDPE) is a synthetic biomaterial used as a three-dimensional scaffold for bone defect reconstruction. Reports differ with regard to its biological response, particularly its osteoconductive capacity. The aim of the present work was to histologically and histomorphometrically evaluate tissue response to porous HDPE. An in vivo study was conducted in rat tibia to evaluate osteogenic capacity, angiogenesis, inflammatory response, and the presence of multinucleated giant cells 14 and 60 days post-biomaterial implantation. Histological examination 14 days post-implantation showed fibrovascular tissue inside pores and on the surface of porous HDPE, acute inflammatory response, scant multinucleated giant cells (MNGCs), and lamellar bone in contact with the biomaterial. An increase in the proportion of lamellar bone tissue, no inflammatory response, and a decrease in the number of MNGCs were observed at 60 days. The histomorphometric study showed a significant time-dependent increase both in the area of bone tissue formed in contact with the porous HDPE (14d: 24.450 ± 11.623 µm2 vs. 60d: 77.104 ± 26.217 µm2, p < 0.05) and in the percentage of bone tissue in contact with the porous HDPE (osseointegration). A significant decrease in the number of MNGCs was also observed at 60 days post-implantation. Porous HDPE showed adequate osteoconductive properties, and only caused an initial inflammatory response. Although this biomaterial has traditionally been used juxtaosseoulsy, its adequate osteoconductive properties broaden the scope of its application to include intraosseous placement. [ABSTRACT FROM AUTHOR]

Copyright of La Revista Latinoamericana de Metalurgia y Materiales, RLMM is the property of Universidad Simon Bolivar, Departmento de Ciencia de los Materiales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Odontologica Latinoamericana: AOL is the property of Acta Odontologica Latinoamericana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Tooth loss leads to a decrease in alveolar bone volume, and consequently to the need for guided bone regeneration (GBR) techniques to restore bone anatomy, and the adequate choice of therapy. Fascia lata membrane (FLM) has been used in surgical procedures in neurology, orthopedics, otorhinolaryngology, cardiology, vascular surgery, gynecology, and dentistry for guided tissue regeneration and Piezosurgery has become a method of choice for cutting bone in a number of GBR procedures. Aim/Hypothesis: The aim of the present study was to perform a qualitative evaluation of bone tissue response in rat calvarial bone defects made using a piezoelectric device and treated with guided bone regeneration with and without placement of FLM, using histological studies. Material and Methods: Eight Wistar rats, 230 g body weight, were subjected to bone surgery to create a 5 × 5 mm long 1 mm deep calvarial bone defect on either side of the median suture, using a piezoelectric scalpel and irrigation. The animals were treated according to the following protocol‐ Group I (GI)‐ placement of a single layer of FLM (Biotar, Rosario, Prov. de Santa Fe, Argentina) to cover the defects, Group II (GII)‐ double layer of FLM to cover the defects, Group III‐ no membrane, Group IV‐ control. All the animals were euthanized 60 days post‐surgery, the heads were resected, radiographed, decalcified, and processed for embedding in paraffin and Hematoxylin‐Eosin and Masson's trichrome staining. Results: None of the bone defects covered with a single (G I) or double (G II) layer of FLM showed an inflammatory response or macrophages, and all exhibited adequate osteogenesis with lamellar bone formation. It is of note that no alterations were observed in the osteocyte lacunae containing osteocytes or in the surgical bed, where the bone defect was created by osteotomy using a piezoelectric scalpel. No alterations and scant osteogenesis were observed in G III and G IV. The fascia lata membranes showed no evidence of alterations in their structure, which consisted mainly of a collagen matrix. No sign of inflammation and no macrophages or giant multinucleated cells were observed at the periphery of the membranes. Conclusions and Clinical Implications: Tissue response to FLM observed 60 days post‐surgery using the experimental model presented here, provides further evidence of the biocompatibility of human fascia lata, as well as of its enhancing effect on osteogenesis during the repair process of experimentally created bone defects. These results show the use of FLM as a successful treatment choice in GBR. Further studies need to be conducted to assess bone tissue response to FLM in combination with bone substitutes. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate thickening of the Schneiderian membrane and to determine its association with periapical pathologies, using computerized cone beam tomography. An observational, analytical, cross-sectional retrospective study was conducted. A total 179 maxillary sinuses were evaluated using CBCT. The presence of sinus membrane thickening and its association with unhealthy teeth was analyzed. Results are shown as percentages with 95% confidence intervals (95%CI); Chi square test was used with a significance level of 5%.Sinus membrane thickening was detected in 70 cases (39%; 95%CI=32% to 46%) and no sinus membrane thickening was observed in 109 (61%; 95%CI = 54% to 68%) (p<0.05). The 70 cases showing sinus membrane thickening included 46 of odontogenic origin (66%; 95%CI = 54% to 76%) and 24 (34%; 95%CI = 24% to 46%) of non odontogenic origin (p<0.05). The frequency of odontogenic causes followed a heterogeneous distribution (p<0.05): penetrating caries, failing endodontic therapy, root remnants, deep restorations, implants, periodontal pathology. The main cause was caries (46%; 95%CI=32% to 60%) followed by failing endodontic therapy (26%, 95% CI=16% to 40%). The frequency distribution of involved teeth was uneven (p<0.05), with tooth 16 (33%; 95%CI=21% to 47%) being the most frequently involved, followed by tooth 26 (30%; 95%CI=19% to 45%).The high incidence of sinus pathology of odontogenic origin shows the need for interdisciplinary work involving dentists and ear-nose-throat specialists. Caries, inadequate restorations, periodontal lesions, implants, and the presence of root remnants are the main causes of Schneiderian membrane thickening. The use of CBCT for diagnosis and treatment planning allows detecting maxillary sinus membrane thickening and determining its association with an odontogenic etiology., (Sociedad Argentina de Investigación Odontológica.)

Tooth loss leads to a decrease in alveolar bone volume, and consequently to the need for guided bone regeneration (GBR) techniques to restore bone anatomy, and the adequate choice of therapy. Fascia lata membrane (FLM) has been used in surgical procedures in neurology, orthopedics, otorhinolaryngology, cardiology, vascular surgery, gynecology, and dentistry for guided tissue regeneration. The aim of the present preliminary study was to evaluate bone tissue response in rat calvarial bone defects covered with human fascia lata membrane (FLM). Eight Wistar rats, 230g body weight, were subjected to bone surgery to create a 5x5mm long/ 1mm deep calvarial bone defect on either side of the median suture, using a piezoelectric scalpel and irrigation. The animals were treated according to the following protocol: Group I (GI): placement of a single layer of FLM (Biotar, Rosario, Prov. de Santa Fe, Argentina) to cover the defects; Group II (GII): double layer of FLM to cover the defects; Group III: no membrane; Group IV: control. All the animals were euthanized 60 days post-surgery; the heads were resected, radiographed, decalcified, and processed for embedding in paraffin and Hematoxylin-Eosin and Masson's trichrome staining. All bone defects covered with a single or double layer of FLM showed adequate osteogenesis, and none exhibited an inflammatory response. Groups III and IV Control showed scant osteogenesis and no alterations in soft tissues. The results obtained with this experimental model show biocompatibility of FML with the surrounding tissues at the studied time points. No alterations were observed in osteocytic lacunae or osteocytes in the bone after osteotomy using a piezoelectric scalpel. Further studies need to be conducted to assess bone tissue response to FLM in combination with bone substitutes., (Sociedad Argentina de Pediatría.)

The dimensions of the alveolar bone surrounding the tooth are not maintained post tooth-extraction probably as a consequence of the bone remodeling process and the biomechanical demands on bone. The use of biomaterials as bone substitutes in the post-tooth-extraction socket promotes bone repair, regardless of damage to bone structures during the surgical procedures. The aim of the present study was to evaluate the effectiveness of anorganic bovine bone matrix (ABBM) as a bone substitute, in an experimental model of post-tooth extraction bone healing in the rat. Radiographic follow-up was performed at 7, 14, and 30 days, and showed persistence of the biomaterial inside the experimental alveoli. At 14 and 30 days post-tooth extraction, particles surrounded by bone tissue were observed in the middle sector of the alveoli. The osteoconductive property of ABBM was demonstrated using the present experimental model of active osteogenesis, thus showing its usefulness as a bone substitute. Persistence of the particles at the studied experimental time points did not affect post-tooth extraction bone healing.

In recent years there has been increasing interest in the choice of the best material for bone substitutes. Experimental models enable estimation of biological potential, efficacy and safety of a biomaterial before its clinical application. The aim of this study was to evaluate the response of a bone substitute, UNC bone matrix powder (MOeP-UNC), for repairing the post-extraction alveolus in Wistar rats. Rats' first lower molars were extracted. The right alveoli were filled with MOeP-UNC hydrated with physiological saline (Experimental Group, EG), and the left alveoli were used as Control Group (CG). Thirty days after extraction, the animals were killed and the samples processed. Histological sections were made in vestibular-lingual direction at the level of the mesial alveolus of the first inferior molar (Guglielmotti et al. J. Oral Maxillofac. Surg. 1985;43(5):359-364). Repair of the alveoli at 30 days after extraction was evaluated histologically. Repair of the alveolus was optimum in the control group at 30 days, and the EG showed presence of MOeP-UNC particles in close contact with newly formed bone tissue (osseointegration). In the experimental model used, at 30 days post-surgery, the MOeP-UNC particles integrate compatibly with newly formed bone tissue.