Geistlich Bio-Oss Research Articles

Histomorphometric and microtomographic analysis of maxillary sinus augmentation surgeries with and without collagen membrane on the lateral window: A randomized clinical trial.

To evaluate the histomorphometric and computerized microtomographic (Micro-CT) analysis of the regenerated bone tissue from maxillary sinus augmentation surgery, with and without using the collagen membrane on the external osteotomy window. Twelve patients were selected for this prospective, controlled, and randomized study. The patients were submitted to bilateral maxillary sinus surgery in a split-mouth design. On the test side, the maxillary sinus augmentation procedure included using Geistlich Bio-Oss® and a Geistlich Bio-Gide® collagen membrane covering the lateral osteotomy window. On the control side, only Geistlich Bio-Oss® was used without the presence of the membrane. After 6 months, the surgeries for implant installation were performed. In this surgical phase, specimens of the regenerated tissue were collected for histological and Micro-CT analysis. In the histomorphometric evaluation, the mean (±SD) percentages of newly formed bone were 43.9% (±11.5) and 40.8% (±8.9) in the test and control groups, respectively. The corresponding values of the Micro-CT analysis were 36.6% (±3.4) and 37.2% (±4.7) in the test and control groups, respectively. There was no statistically significant difference between the test and control groups in the two methods. In addition, there was no statistically significant difference between the mean percentage of biomaterial remaining between the test and control groups. However, the mean percentage of newly formed bone was significantly higher and the mean percentage of remaining biomaterial was significantly lower in the histomorphometric analysis compared to the values obtained through microtomography. The additional use of collagen membranes in maxillary sinus surgery does not offer advantages in newly formed bone.

The Added Value of a Collagenated Thermosensitive Bone Substitute as a Scaffold for Bone Regeneration.

A pre-hydrated thermosensitive collagenated biomaterial which sets at body temperature and maintains the space of the missing alveolar bone volume, OsteoBiol GTO® (GTO), has been released as a bone substitute. This study was designed to check its angiogenic and osteogenic potentials compared to OsteoBiol Gen-Os® (Gen-Os) and Geistlich Bio-Oss® (Bio-Oss). Samples of materials were incubated in culture media to obtain the extracts. Collagen release was measured in the extracts, which were used to investigate human periodontal ligament (hPDL) cell proliferation (MTT), colonization (Scratch assays) and growth factor release (ELISA). The effects on endothelial cell proliferation (MTT) and organization (Matrigel® assays) were also studied. Finally, endothelial and mesenchymal Stem Cell (hMSC) recruitment (Boyden Chambers) were investigated, and hMSC Alkaline Phosphatase (ALP) activity was measured. A higher collagen concentration was found in GTO extract, which led to significantly higher hPDL cell proliferation/colonization. All materials increased VEGF/FGF-2 growth factor secretion, endothelial cell recruitment, proliferation, and organization, but the increase was highest with GTO. All materials increased hMSC recruitment and ALP activity. However, the increase was highest with collagenated GTO and Gen-Os, which enhanced C5a and BMP-2 secretion. Overall, GTO has higher angiogenic/osteogenic potentials than the collagenated Gen-Os and the anorganic Bio-Oss. It provides a suitable scaffold for endothelial and mesenchymal stem cell recruitment, which represent essential bone regeneration requirements.

Bacteria-responsive, Cell-recruitable, and osteoinductive nanocomposite microcarriers for intelligent bacteriostasis and accelerated tissue regeneration

Repairing alveolar bone defects with chronic periodontitis is a major clinical challenge, since the periodontitis causes the intermittent bacteria invasion to irreversibly aggravates the degeneration of alveolar bones. To deal with the challenge, a kind of novel microcarriers with excellent abilities of responding to alkaline phosphatase (ALP) to intelligently eliminate the bacteria and promoting the recruitment and osteogenic differentiation of endogenous stem cells are developed. Mesoporous silica nanocarriers that chemically fix the polyethylene glycol-modified amoxicillin (PEG-AML) through the phosphoester groups and electrostatically adsorb the aspirin (ASP) are first prepared. The nanocarriers are then dispersed in a chitosan solution to prepare the bacteria-responsive, cell-recruitable, and osteoinductive nanocomposite microcarriers. When being stimulated by ALP that are secreted by the bacteria, phosphoester groups of microcarriers are cleaved, and PEG-AML are delivered on demand to well achieve the goal of intelligent bacteriostasis. The microcarriers slowly release the ASP to promote the recruitment and osteogenic differentiation of endogenous stem cells. At 8 weeks post-implantation, the microcarriers facilitate the repair of alveolar bone defects with periodontitis. The blood vessels in the neo-generated alveolar bones grow well. Due to the appropriate degradation time and excellent antibacterial ability of microcarriers, the microcarriers exhibit a better therapeutic efficacy than the standard clinical products (Geistlich Bio-Oss®), providing a new insight into the cure of alveolar bone defects with periodontitis.

Epigallocatechin-3-gallate improves the biocompatibility of bone substitutes in dental pulp stem cells

BackgroundThe Biocompatibility between osteoprogenitor cells and bone substitutes is necessary for cell differentiation and osteogenesis. The aim of this study was to assess the in vitro effect of bovine (Geistlich BioOss®), porcine (OsteoBiol Gen-Os®) and beta-tricalcium phosphate (Cerasorb M®) bone substitutes, and their combination with polyphenol epigallocatechin-3-gallate (EGCG), upon cultured dental pulp stem cells (DPSCs). MethodsThe DPSCs were isolated from third molars extracted from healthy individuals and seeded with 5 mg/ml of Bio-Oss® (BO), Gen-Os® (GO) and Cerasorb® (CE) in combination with EGCG 1 μM. The effects were evaluated based on cell viability / cytotoxicity assay (MTT, cell viability staining test), cell migration, scanning electron microscopy (SEM), and alkaline phosphatase (ALP) activity. ResultsBO and CE produced negative effects upon cell viability and migration, and GO and CE resulted in deficient cell adhesion. On the other hand, all the biomaterials exerted no negative effects upon ALP activity. Interestingly, the addition of EGCG reverted the cytotoxic effect and the loss of migration capacity in the BO and CE groups, and improved cell adhesion in the GO and CE groups. Furthermore, EGCG promoted an overall increased in ALP activity. ConclusionThe addition of EGCG to the tested biomaterials BO, GO and CE reverts their negative impact on DPSCs, and improves their biocompatibility with cultured DPSCs. The use of EGCG, thus, appears to be a promising strategy for restoring and enhancing the osteoconductive properties of BO, GO and CE in bone regeneration treatments.

Microcarriers containing “Hypoxia-engine” for simultaneous enhanced osteogenesis and angiogenesis

Currently, most practiced strategies for accelerating bone healing are introducing osteoinductive factors such as growth factors, osteogenic pharmaceuticals, and inorganic ions. However, uncontrollable side effects such as hematoma limit their clinical applications. Inspired by the crowded subway, a kind of novel hierarchically porous and hollow microcarriers containing multicellular spheroids and adhesive cells are developed to not only avoid the utilization of osteoinductive factors but also promote the regeneration of vascular bone tissues. The hierarchically porous and hollow structures are formed based on a new hierarchical pore forming mechanism called “centripetal force-driven multistage separation”, where the diameters of macropores and micropores are 241 μm and 13 μm. Multicellular spheroids in the microcarriers serve as the “Hypoxia-engine” to produce the hypoxia-inducible factor (HIF-1α) to significantly increase the expression of osteogenic and angiogenic factors. Adhesive cells in the microcarriers proliferate to facilitate the development of new bones. After being implanted, the microcarriers containing “Hypoxia-engine” accelerate the regeneration of vascular alveolar bone tissues. The neogenerated alveolar bones well integrated with the healthy bones due to the hierarchical pore structure. Imageological, histological, immunohistochemical, and biomechanical evaluation prove that the treatment efficacy of microcarriers containing “Hypoxia-engine” generally reaches that of the standard clinical grafts (Geistlich Bio-Oss®).

Efficiency of guided bone regeneration in vertical bone augmentation with titanium-reinforced PTFE membrane and platelet-rich fibrin

Objective: Guided bone regeneration (GBR) for vertical bone augmention is an easy-to-implement approach and has a good prognosis. However, there are many different procedures that lead to different clinical outcomes. The use of platelet-rich fibrin (PRF) can improve outcomes in regenerative treatments. Therefore, this study aimed to evaluate the effectiveness of vertical bone grafting by guided bone reconstruction with titanium-reinforced PTFE membrane combined with PRF. Materials and Methods: Nine patients who come to the Department of Odonto-Stomatology, University of Medicine and Pharmacy, Ho Chi Minh City, have a need for implant treatment and have mild to moderate vertical bone deficiency. Patients are treated with bone grafting by GBR technique: using a mixture of bone grafts including autogenous bone and deproteinized bovine bone (Geistlich Bio-Oss) at a ratio of 1:1, mixed with injectable form PRF in the form of sticky bone. The vertical bone defects were protected by a titanium-reinforced d-PTFE membrane and covered by an A-PRF+ membrane. The bone gain was measured using a cone-beam computed tomography at baseline and after a period of 8 months. Results: Analyzing the research results on 9 patients, 15 research units corresponding to 15 bone grafting sites, the GBR procedures an increase in bone height (p < 0,05) after treatment. In the two-staged approach, the vertical bone gain was 3.97 ± 0.92 mm; in the group of simultaneous one-staged procedure, the vertical bone gain was 3.89 ± 1.13 mm. In general, the bone height of the study sample achieved an average of 94.16 ± 10.7% compared to the ideal bone height. Conclusion: GBR technique using a mixture of particulate autogenous bone and xenogenous bone and PRF is effective for vertical bone augmentation in maxillary and mandibular regions, ensuring favorable bone morphology, permitting sufficient bone gain to future implant placement and prosthetics.

Xenogeneic bone mineral is efficient for the repair of critical-sized rat calvarial defects

Aim. To evaluate the efficiency of bone repair on a critical-sized rat calvarial defect model using our original xenogeneic bone mineral, widely established Geistlich Bio-Oss®, and autologous bone graft.Materials and Methods. We created a critical-sized calvarial defect in Sprague-Dawley rats (n = 48) and then divided them into 4 groups (unfilled defect, autologous bone graft, Geistlich BioOss® and our original xenogeneic bone mineral, 12 rats per group). Rats were sacrificed upon 4 and 12 months (6 rats per time point) with the following excision of the implant and adjacent tissues. 3D structure, extent of mineralisation, and bone volume were measured by means of microcomputed tomography. Microanatomy of the explants and adjacent tissue was investigated by haematoxylin and eosin staining.Results. The highest and the lowest bone volume was expectedly detected when the defect was filled with the autologous bone graft or remained unfilled, respectively. Replacement of the defect by the original bone mineral entailed better regeneration as compared to Geistlich Bio-Oss. Bone mineral density, bone thickness and the extent of mineralisation did not differ significantly between the experimental groups and were close to the positive control values, indicating efficient bone repair.Conclusions. Original xenogeneic bone mineral promotes induction of bone regeneration as compared to Geistlich Bio-Oss®, a commercially available bone mineral widely used in the clinical practice.

Effect of extracellular matrix and dental pulp stem cells on bone regeneration with 3D printed PLA/HA composite scaffolds.

The demand for bone grafting procedures in various fields of medicine is increasing. Existing substitutes in clinical practice do not meet all the criteria required for an ideal bone scaffold, so new materials are being sought. This study evaluated bone regeneration using a critical-size Wistar rat's calvarial defect model. 12 male and 12 female rats were evenly divided into 3 groups: 1. Negative and positive (Geistlich Bio-Oss®) controls; 2. polylactic acid (PLA) and PLA/hydroxyapatite (HA); 3. PLA/HA cellularised with dental pulp stem cells (DPSC) and PLA/HA extracellular matrix (ECM) scaffolds. PLA/HA filament was created using hot-melt extrusion equipment. All scaffolds were fabricated using a 3D printer. DPSC were isolated from the incisors of adult Wistar rats. The defects were evaluated by micro-computed tomography (µCT) and histology, 8 weeks after surgery. µCT revealed that the Bio-Oss group generated 1.49 mm3 and PLA/HA ECM 1.495 mm3 more bone volume than the negative control. Histology showed a statistically significant difference between negative control and both (Bio-Oss and PLA/HA ECM) groups in rats of both genders. Moreover, histology showed gender-specific differences in all experimental groups and a statistically significant difference between cellularised PLA/HA and PLA/HA ECM groups in female rats. Qualitative histology showed the pronounced inflammation reaction during biodegradation in the PLA group. In conclusion, the bone-forming ability was comparable between the Bio-Oss and PLA/HA ECM scaffolds. Further research is needed to analyse the effects of ECM and PLA/HA ratio on osteoregeneration.

Histologic and histomorphometric analysis of two biomaterials of xenogenous origin for maxillary sinus elevation: a clinical study.

Objective: This study analyzed two xenogenous biomaterials based on deproteinized bovine bone mineral applied for maxillary sinus elevation. Method and materials: Fourteen patients were submitted to maxillary sinus augmentation with one of the following biomaterials: Criteria Lumina Bone Porous (test group) or Geistlich Bio-Oss (control group), both of large granules (1 to 2 mm). After 6 months, trephine biopsies were collected at the time of implant placement: 27 samples (11 patients) in the test group; 7 samples (3 patients) in the control group. Biopsies were analyzed by descriptive histology and histomorphometry, in which the percentages of newly formed bone, residual biomaterial particles, and connective tissue were evaluated. Results: Histomorphometry showed means for test and control groups, respectively, of 32.41% ± 9.42% and 26.59% ± 4.88% for newly formed bone, 22.89% ± 4.58% and 25.00% ± 4.81% for residual biomaterial, and 44.70% ± 9.54% and 48.41% ± 3.36% for connective tissue. There were no differences between groups (P > .05). Conclusion: This study concluded that Criteria Lumina Bone Porous presented similar histologic and histomorphometric characteristics to Geistlich Bio-Oss 6 months after sinus elevation surgery, identifying the tested biomaterial as an interesting alternative for bone augmentation in the maxillary sinus.

Reabilitação dentária em região anterior com implante imediato e reconstrução alveolar por meio de enxertos conjuntivo autógeno e ósseo xenógeno

The immediate implant, in addition to provide reduction of clinical treatment time, aims to promote preservation of marginal bone ridges and maintain the emergency profile of the dental crown. The present study shows a clinical procedure involving minimally traumatic extration, followed by the immediate installation of a morse taper implant (Alvim 3,5 x 13 mm, Neodent®) in addition to the use of subepithelial connective tissue graft (SCTG). In order to remedy a loss of remnant alveolar bone tissue, bovine biomaterial (Geistlich Bio-Oss®) was used in alveolar reconstruction also with the intention of covering implant’s spires and promoving stability for the recently grafted soft tissue. After the surgical installation of the implant was completed, an initial 30N locking was obtained, what made impossible the immediate installation of a provisional over the implant. Then fixed temporary restoration was carried out, using a pontic with cervical ovoid format to maintain height, emergency profile, and interdental papilla contour. After 4 months of postoperative, was carried out surgery of implant reopening, with a new graft of connective tissue using the technique called pediculated, aiming the gain of vestibular tissue volume. Universal abutment type prosthetic component morse taper was used (measuring 3,3 x 4 x 6,5 mm Neodent®) and was carried out the confection and cementation of implant supported provisional. After a few weeks, the definitive crown was installed. With those procedures, for proper planning, and highly regarded techniques, a highly satisfactory functional and aesthetic result could be obtained.

Heterologous demineralised bone matrix is efficient for the repair of critical-sized rat calvarial defects

Aim. To evaluate the efficacy of heterologous demineralised bone matrix (DBM) for the replacement of bone defects using a critical-sized rat calvarial defect model. Materials and Methods. For the experiments, we used 48 Sprague-Dawley rats (4.5 to 6 months of age). Critical-sized (8 mm diameter) calvarial defect was filled by the bone autograft, heterologous DBM, or comparator product (Geistlich BioOss®) or remained unfilled (negative control). Upon 4 or 12 weeks, rats were euthanised with the subsequent investigation of the defect and adjacent tissues by means of hematoxylin and eosin staining (mineralized tissue area to the defect area ratio) and microcomputed tomography (volume, thickness, and mineral density of the repaired tissue). Results. In our experimental setting, bone autograft was the most efficient in bone repair. Heterologous DBM and comparator product were equally efficient in filling the defect and did not show any statistically significant differences regarding any of the parameters. Microcomputed tomography and routine histological examination demonstrated concordant results. Conclusion. Heterologous DBM is efficient for the repair of critical-sized rat calvarial defects.

Аpplication of xenogeneic native bone collagen for bone repair in critical-sized rat calvarial defect model

Aim. To evaluate the efficacy of bone repair using xenogeneic native bone collagen (Bongraf COLLAGEN) as compared to other widely applied orthopaedic solutions (xenogeneic native bone mineral Geistlich Bio-Oss® and bone autograft).Materials and Methods. We employed a conventional critical-sized (8 mm) rat calvarial defect model (48 Wistar or Sprague-Dawley rats). The artificial defect was repaired using Bongraf COLLAGEN, Geistlich Bio-Oss® utilised as a comparator, bone calvarial autograft, or remained unfilled (n = 6 per group). Rats were euthanised 4 or 12 weeks postimplantation (n = 3 per time point) with the subsequent examination (repair extent, volume, thickness and mineral density of the repaired tissue) by means of microcomputed tomography and hematoxylin and eosin staining.Results. Expectedly, highest volume, thickness and mineral density of the repaired tissue have been observed in defects filled with autografts. Bongraf COLLAGEN and Geistlich Bio-Oss® also demonstrated a comparable and significant repair capability, yet the former option demonstrated higher bone regeneration rate.Conclusion. Xenogeneic native bone collagen (Bongraf COLLAGEN) is comparable with xenogeneic native bone mineral (Geistlich Bio-Oss®).

Use of Biomaterials for Periodontal Regeneration: A Review

BACKGROUND: Management of bone periodontal defects, destruction, and loss of the alveolar bone is considered a challenge for modern periodontal regeneration and implant dentistry. Numerous of biomaterials are being used in periodontal regenerative treatment.
 AIM: This study aims to know the characteristics of biomaterials and their efficiency in periodontal surgical treatment as regenerative therapy.
 METHODS: A systematic review of the literature considering reviews, clinical studies, original papers, and articles from electronic data has been used.
 RESULTS: Different biomaterials such as Straumann® Emdogain®, Geistlich Bio-Oss®, MIS 4MATRIX – Bone Graft, Platelet-rich fibrin (PRF), Mis Bone-4MATRIX, and PRF are being used for periodontal regeneration treatment, hence revealing more effective outcomes when combined. PRP together with conventional grafting procedures may be a beneficial treatment approach, guided tissue regeneration with bioabsorbable membranes in combination with Bio-Oss are stable on a long-term basis.
 CONCLUSION: Biomaterials being used in periodontal surgical treatment have the different regenerative ability. The combined use of biomaterials might result in a better clinical outcome. There are also a number of other biomaterials used to treat periodontal regeneration, but generally all have the same ability and the same molecular structure as highlighted in this literature review.

Experimental Study on Biochemical Markers of Mandibular Bone Tissue Metabolism in Rats following the Implantation of PAW-1 and Geistlich Bio-OSS Collagen

The study is based on the analysis of experimental results and determination of the bone metabolism markers by histochemical and biochemical methods performed on animals. The animals were implanted biovitroceramics PAW-1 in the mandible in the form of spongy matrix composed of fluorhydroxyapatite and microcrystallized wollastonite in a glass matrix, elaborated by the company PONETI (Romania) and Geistlich Bio-Oss-Collagen in the form of block (a mixture of granules, 0.25-1mm in size) and 10% fibers of porcine collagen. Geistlich Bio-Oss Collagen is a natural mineral bone of bovine origin, comparable both chemically and structurally to the mineralized human bone. It has a spongy consistency that allows simple modeling, and collagen facilitates the adaptation of the material on the defect site.The biochemical blood analysis showed an increased activity of bone thermolabile alkaline phosphatase over 30 days, the maximum being reached over 60 days + 20% (p[0.05) from the beginning of the experiment. The activity of tartrate-resistant bone acid phosphatase, on the contrary, decreased veridically by 22% over 60 days after implantation. Over 30 days after the beginning of the experiment under the action of the implanted material, the level of average molecules (AM) increased by 35% (p [0.05), while nucleotide substances (NS) increased by 51% (p [0.05). Within 60 days after implantation, the values of these indices showed a decreasing tendency. The fact mentioned above denotes that their osteoregenerative action increases under the influence of implanted materials.

Customized fixation guide associated with bio-graft® to promote bone union and skeletal stability in mentoplasty

Background: Orthognathic surgery is the standard procedure to restore function and facial esthetics, correct skeletal and occlusal discrepancies in patients with facial deformities. Incomplete ossification between bone segments has proven to be a major problem when mentoplasty is performed, particularly if pseudarthrosis occurs. Bone grafts were introduced in recent years in order to promote bone union and prevent such complications. Among the biomaterials available, Geistlich Bio-Oss® has been used with success. The Bio-Graft® is a natural bone material of equine origin that emerges as a new bone graft alternative to prevent nonunion of the bone segments. Currently, simplified techniques are being developed for mentoplasty using customized guides manufactured with three-dimensional (3D) printing technology. The use of customized fixation guides allows the virtual surgical planning to be reproduced more accurately and reliably in unstable and surgical movements as clockwise rotations of the chin or vertical increasing.

Cappellin simplified sinus lift protocol for mini-invasive lateral approach - Preliminary study results

Purpose: The lateral approach in sinus lift allows to optimally manage severe bone resorption in posterior maxilla in order to place implant supported prosthesis; however, the conventional protocols requires bigger window and cannot determine in advance the precise position for bone incision, so in many cases the detachment of Schneider membrane is more difficult if the bone isn’t cut near the sinus floor or if there is a bone septum. The aim of Cappellin simplified sinus lift protocol is to minimize the surgical difficulties with a surgical guide realized from STL 3D printed model (conversion of DICOM cone-beam CT files). Case report: In our study (since 2013 to 2017) in 125 sinus lift cases (performed with Geistlich Bio-Oss® and a-PRF / PRGF) with 210 implants (Implant Direct® Legacy 2, 78 of which were placed at the same time as the sinus lift augmentation) we obtain a success of 100% for the sinus lift augmentation and 100% survival rate for the implants; we also drastically reduce the surgery time (average is about 25 minutes). CT scans were performed before the surgery and 4-6 months after the sinus lift; follow up for implant survival includes control and professional hygiene every 6 months. Conclusions: In regards of these preliminary results, Cappellin simplified sinus lift protocol offers advantages in terms of safety, simplicity, quickness, reliability and allows to reduce the economic costs of the procedure.

New nano-hydroxyapatite in bone defect regeneration: A histological study in rats

Many types of bone substitute materials are available on the market. Researchers are refining new bone substitutes to make them comparable to autologous grafting materials in treatment of bone defects. The purpose of the study was to evaluate the osseoconductive potential and bone defect regeneration in rat calvaria bone defects treated with new synthetic nano-hydroxyapatite. The study was performed on 30 rats divided into 5 equal groups. New preproduction of experimental nano-hydroxyapatite material by NanoSynHap (Poznań, Poland) was tested and compared with commercially available materials. Five mm critical size defects were created and filled with the following bone grafting materials: 1) Geistlich Bio-Oss®; 2) nano-hydroxyapatite+β-TCP; 3) nano-hydroxyapatite; 4) nano-hydroxyapatite+collagen membrane. The last group served as controls without any augmentation. Bone samples from calvaria were harvested for histological and micro-ct evaluation after 8 weeks. New bone formation was observed in all groups. Histomorphometric analysis revealed an amount of regenerated bone between 34.2 and 44.4% in treated bone defects, whereas only 13.0% regenerated bone was found in controls. Interestingly, in group 3, no significant particles of the nano-HA material were found. In contrast, residual bone substitute material could be detected in all other test groups. Micro-CT study confirmed the results of the histological examinations. The new nano-hydroxyapatite provides comparable results to other grafts in the field of bone regeneration.

Extraordinary biological properties of a new calcium hydroxyapatite/poly(lactide-co-glycolide)-based scaffold confirmed by in vivo investigation.

This study examined the potential of a new porous calcium hydroxyapatite scaffold covered with poly (lactide-co-glycolide) (PLGA) as a bone substitute, identifying its advantages over Geistlich Bio-Oss®, considered the gold standard, in in vivo biofunctionality investigations. Structural and morphological properties of the new scaffold were analyzed by scanning electron and atomic force microscopy. The biofunctionality assays were performed on New Zealand white rabbits using new scaffold for filling full-thickness defects of critical size. The evaluated parameters were: the presence of macrophages, giant cells, monoocytes, plasma cells, granulocytes, neoangiogenesis, fibroplasia, and the percentage of mineralization. Parallel biofunctionality assays were performed using Geistlich Bio-Oss®. The appearance of bone defects 12 weeks after the new scaffold implantation showed the presence of a small number of typical immune response cells. Furthermore, significantly reduced number of capillary buds, low intensity of fibroplasia and high degree of mineralization in a lamellar pattern indicated that the inflammation process has been almost completely overcome and that the new bone formed was in the final phase of remodeling. All biofunctionality assays proved the new scaffold's suitability as a bone substitute for applications in maxillofacial surgery. It showed numerous biological advantages over Geistlich Bio-Oss® which was reflected mainly as a lower number of giant cells surrounding implanted material and higher degree of mineralization in new formed bone.

In VivoInvestigation of ALBO-OS Scaffold Based on Hydroxyapatite and PLGA

A synthetic bone substitute based on calcium hydroxyapatite (CHA) and poly(lactic-co-glycolic) acid (PLGA), described in this paper, was synthesized to fulfill specific requirements like biodegradability, satisfying mechanical properties, optimal porosity and nanotopology, osteoinductive and osteoconductive properties, and so forth. Structural and morphological properties of the new scaffold were analyzed by micro computed tomography and scanning electron microscopy, while its physicochemical properties were investigated by X-ray diffraction and infrared spectroscopy.In vivobiological investigations of the synthesized scaffold were conducted over the cutaneous irritation and biofunctionality assays on rabbits and the test of acute systemic toxicity on mice. The results showed that the scaffold is not irritant and that it does not exhibit any symptoms of acute toxicity. Biofunctionality assays which include evaluation of the presence of various cells of immune response, the presence of neoangiogenesis, percentage of mineralization of newly formed bone, and fibroplasia in the tissue indicated that the new scaffold is suitable for the application in maxillofacial and dental surgery as a bone substitute. Also, it showed significant advantages over commercial product Geistlich Bio-Oss® from the aspect of some parameters of immunological response.

Predictors of Alveolar Process Remodeling Following Ridge Preservation in High-Risk Patients.

(1) To clinically evaluate horizontal remodeling of the alveolar process (hard and soft tissues) following ridge preservation in high-risk patients and (2) to identify predictors of such remodeling. Periodontally healthy nonsmoking patients with a failing tooth in the anterior maxilla (15-25) were selected for a prospective case series. All were in need of a single implant and demonstrated high risk for aesthetic complications given an incomplete buccal bone wall and/or thin-scalloped gingival biotype. Following flapless tooth extraction, ridge preservation was performed using one or more collagen-enriched, bovine-derived block grafts (Geistlich Bio-Oss® Collagen® 100 mg, Geistlich Pharma AG, Wolhusen, Switzerland) without the additional use of membranes or soft tissue grafts. The change in buccopalatal dimension of the alveolar process between baseline (prior to tooth extraction) and 4 months was assessed on the basis of superimposed occlusal slides. Regression analysis was performed to identify predictors of alveolar process remodeling. Forty-two patients (21 females, 21 males; mean age 38) met the selection criteria and consented to the treatment. Mean alveolar process remodeling was 14% (SD 7, range 4-30) with minimal remodeling (≤ 10%) in 16 patients (38%) and advanced remodeling (>20%) in 10 patients (24%). A single implant could be installed in all subjects without additional guided bone regeneration. Connective tissue grafting was performed later on in the treatment for aesthetic purposes, hereby compensating for tissue loss at the buccal aspect. Predictors of alveolar process remodeling were tooth location (central incisors and cuspids > laterals incisors and premolars), tooth abscess (p = .025), and buccal bone loss (p = .035). Alveolar process remodeling seems inevitable yet acceptable following ridge preservation in high-risk patients. Proper case selection may reduce the incidence of advanced remodeling.