Angiogenic response to bioactive glass promotes bone healing in an irradiated calvarial defect

Localized radiation is an effective treatment modality for carcinomas, yet the associated reduction of the host vasculature significantly inhibits the tissue's regenerative capacity. Low concentrations of bioactive glass (BG) possess angiogenic potential, and we hypothesized that localized BG presentation would increase neovascularization and promote healing in an irradiated bone defect. An isolated calvarial region of Sprague-Dawley rats was irradiated 2 weeks before surgery. Bilateral critical-sized defects were created and immediately filled with a BG-loaded collagen sponge or an empty sponge as an internal control. Histological analysis of calvaria collected after 2 weeks demonstrated greater neovascularization within the defect in the presence of BG than with collagen alone. Noninvasive ultrasound imaging at 4 weeks detected less contrast agent in the brain below BG-treated defects than in the nearby untreated defects and images of treated defects acquired at 2 weeks. The reduced ability to detect contrast agent in BG-treated defects suggested greater attenuation of ultrasound signal due to early bone formation. Micro-computed tomography imaging at 12 weeks demonstrated significantly greater bone volume fraction within BG-treated defects than in controls. These results suggest that neovascularization induced by localized BG delivery promotes bone regeneration in this highly compromised model of bone healing and may offer an alternative approach to costly growth factors and their potential side-effects.

An update on bone substitutes for spinal fusion

With the current advances in spinal surgery, an understanding of the precise biological mechanism of each bone substitute is necessary for inducing successful spinal fusion. In this review, the categories of bone substitutes include allografts, ceramics, demineralized bone matrix, osteoinductive factors, autogenous platelet concentrate, mesenchymal stem cells, and gene therapy. Further, clinical studies have been evaluated by their levels of evidence in order to elucidate the precise effect of the bone substitute employed and to establish clinical guidance. This article will review both clinical studies based on evidence and basic research in current advances in order to avoid as far as possible any chances of failure in the future and to understand cellular biology in novel technologies.

[Biomaterials in articular cartilage lesions repair]

Osteoarthritic symptoms following articular cartilage injuries are the most common musculoskeletal system disease. The treatment possibilities search for methods to restore and bring back the function of injured joint surfaces. Recent trend heads for creation of biocompatible matrices (scaffolds) based on natural and synthetic polimers. This study presents currently used biomaterials in the sphere of their usefulness in articular cartilage lesions repair. Both natural and synthetic materials have been researched in experimental and clinical studies. Naturally- derived protein polymers, such as collagen, fibrin, gelatin and carbohydrate polymers containing polylactide and polyglycolic acid, hialuronan, agarose, alginate, chitosan can be distinguished. Synthetic materials are represented by carbon fibers, Dacron and Teflon matrices. Scaffolds fabrication techniques include fiber-bonding, particulate leaching, freeze- drying and particles aggregation. Due to different polymers' properties selection of a scaffold depends on an appropriate matrix parameters. The most valuable characteristics are biocompatibility, porosity, mechanical resistance and bioabsorbability. Notwithstanding, several experimental and clinical studies there still exists the need for one simple and inexpensive polymer- based method that would bring satisfactory results in the area of joint cartilage repair.

Effect of silica precursors-type on mechanical properties of sol-gel coatings

Reversion to narrowing, called restenosis, still remains an important problem of coronary angioplasty. Analysis of the problem revealed that the application of surface layers aimed at creating on the stent surface a neutral barrier between its metallic framework and tissues of the blood-vascular system is decidedly best to impede the restenosis. They also play the role of medicine carriers. This article presents a new sol-gel technology, to be applied in coronary stent coatings. Currently, this is one of the most progressive methods allowing the modification of surface layers of metallic biomaterials. The results presented prove that due to a proper selection of silica precursors it is possible to obtain continuous, smooth, plastic deformation-resistant sol-gel coatings, which additionally are characterised by very close adherence to the base material, nanometer thickness and low degree of surface development.

Properties of calcium carbonate-containing composite scaffolds

Bone grafting in skeletal reconstruction has become a common task of orthopedic surgeon. Three-dimensional, porous, degradable scaffolds are often used to provide support while the new tissue can be formed in situ. There are numerous materials and techniques involved; however, each has certain drawbacks. One of the patented ceramic bone grafts is made of coral that has many benefits, e.g., its chemical and surface structure similar to that of the cancellous bone, extremely good biocompatibility and optimal pore-size. The drawback, being difficult to overcome, is the manufacturing to the desired shape. In order to maintain the advantageous chemical composition, but to overcome these difficulties, we have manufactured polymer-ceramic scaffolds both by solvent casting and by melt mixing and particulate leaching. The scaffold morphology was examined using scanning electron microscope (SEM), while the compressive properties were chosen to validate these substrates mechanically.

Grafting of tooth extraction socket with inorganic bovine bone or bioactive glass particles: comparative histometric study in rats

PURPOSE

To compare histometrically, in rats, the bone healing after grafting the incisor extraction sockets with inorganic bovine bone or bioactive glass particles.

MATERIAL

The volume fraction of grafted materials and alveolar healing components was estimated in histologic images at the end of the second and ninth weeks postoperatively by a differential point-counting method.

RESULTS

Both materials were histologically observed partially filling the cervical alveolar third and, although evoking neither a foreign body reaction nor a persisting inflammatory response, delayed new bone formation in trial areas around their particles. By the second week, the delay in bone healing was more pronounced in the animals grafted with inorganic than in those grafted with bioactive glass, and an opposing result was observed during a 9-week period.

CONCLUSION

Both inorganic bovine bone and bioactive glass particles grafted in the incisor extraction sockets of rats delayed new bone formation, and the degree of impairment resulted from a combination of factors such as type of material and phase of the reparation process.

The development of magnetic degradable DP-Bioglass for hyperthermia cancer therapy

In this study, a novel magnetic degradable material was developed by adding Fe ions into DP-Bioglass (Na(2)O-CaO-P(2)O(5)-SiO(2)) as thermoseed for hyperthermia cancer therapy under an alternating magnetic field. We have investigated the properties of developed magnetic DP-Bioglass including morphology, chemical composition, and magnetism. The degradability was conducted by measuring the released concentrations of Na, Ca, Si, P, and Fe ions. The biocompatibility was analyzed by biological assays, and the functional hyperthermia effect to cancer cells was evaluated by in vitro cell culture test. In the results, the morphology of synthesized magnetic DP-Bioglass was revealed in sphere and rod shape with particle size around 50-100 nm. From the hysteresis loop analysis, it showed that the group of Fe/Bioglass = 0.2 possessed the maximum magnetization property. When cultured with fibroblasts, the magnetic DP-Bioglass had no significant influence on cell viability and mediated low cytotoxicity. The thermal-induced property demonstrated that after exposure to an alternating magnetic field, the cell number of human Caucasian lung carcinoma cells (A549) was significantly decreased when temperature was increasing to 45 degrees C. In brief, successfully incorporated with Fe ions by sol-gel method, this magnetic degradable DP-Bioglass possessed the potential and properties of hyperthermia effect to lung carcinoma cells.

The aesthetic replacement of mandibular incisors using an implant-supported fixed partial denture with gingival-colored ceramics

Restoration of the anterior dentition using dental implants can be technically demanding. Loss of the supporting hard and soft tissue structures diminishes the clinician's ability to obtain optimal results. The use of gingival-colored ceramics offers on effective method of developing aesthetics when reconstructive surgery is not an option. This article describes the use of gingival-colored porcelain in creating a natural-looking, implant-supported fixed partial denture to replace compromised mandibular incisors.

Tracheal Ceramic Rings for Tracheomalacia: A Review After 17 Years

BACKGROUND

Despite different support techniques, the surgical management of tracheomalacia is still a challenging problem. Satisfactory results after internal stenting are above 80%, whereas, when performing external stenting using biocompatible ceramic rings, results are reported at over 90%.

OBJECTIVE

The purpose of this study was to examine the efficiency of surgical treatment in patients with segmentary tracheomalacia using external ceramic ring grafts.

METHODS

In this retrospective study, we collected data from 12 patients who underwent surgery during the last 17 years for symptomatic segmentary tracheomalacia by use of biocompatible aluminum-oxide ceramic rings. All except one patient had undergone previous tracheostomy, six had a history of long-term intubation, two had previous trauma, and two patients had previous cancer treatment including radiotherapy. One of the patients still had an existing tracheostoma, which was closed when a ceramic ring was implanted. Tracheal wall collapse with pseudoglottis formation or flattened anterior-posterior tracheal diameter was documented with fiberoscopy at rest, and both pre- and postoperative airway resistance measurements were performed in all 12 patients using a spirometer. After malacic segments were found to be expandable using rigid tracheoscopy while the patient was under general anesthesia, preparation of the trachea was performed using a midline vertical incision in the neck. Subsequently, the malacic trachea was expanded by placing and suturing proper-sized ceramic ring(s) around it.

RESULTS

In all patients, surgical expansion of the malacic segment using ceramic rings was successfully carried out without major complications while inspiratory stridor was resolved. Airway resistance decreased significantly from an average of 0.62 to 0.385 kPascal.

CONCLUSION

Although the results of applying internal tracheal stents are encouraging, complications such as stent migration, granulation tissue and fistula formation, and mucociliary transport arrest are possible. Biocompatible ceramic rings do not cause foreign body reactions, remain stabile, and, with a proper suturing technique, provide a suitable long-term solution.

The use of osteoconductive bone graft substitutes in orthopaedic trauma

Several bone graft substitutes are now available for use in augmenting bone healing following trauma. Many of these products are osteoconductive and are indicated for filling bone defects in conjunction with standard methods of internal and external fixation. Osteoconduction refers to a process in which the three-dimensional structure of a substance is conducive for the ongrowth and/or ingrowth of newly formed bone. Currently used bone graft substitutes that primarily offer osteoconductive properties include coralline hydroxyapatite, collagen-based matrices, calcium phosphate, calcium sulfate, and tricalcium phosphate. These products vary considerably in chemical composition, structural strength, and resorption or remodeling rates. Understanding these differences is important in selecting a bone graft substitute with the properties desired for a specific clinical situation. The limited number of clinical studies and lack of direct-comparison studies between these products require the surgeon to fully understand the properties of each product when choosing a bone graft substitute.

Clinical evaluation of platelet-rich plasma and bioactive glass in the treatment of intra-bony defects

BACKGROUND

There are limited numbers of studies focused on the using of platelet-rich plasma (PRP) combined with different types of bone substitutes in intra-bony defects.

AIM

The purpose of this study was to evaluate the effect of bioactive glass graft material (BG) with and without PRP on the clinical healing of intra-bony defects.

MATERIALS AND METHODS

Twenty-nine intra-bony defects were randomly treated with either PRP/BG or BG alone. Clinical parameters were recorded at baseline and repeated 9 months after surgery and surgical reentries were also performed.

RESULTS

The results showed that both treatment modalities were effective. Pocket depth reduction of 3.60 +/- 0.51 mm, clinical attachment gain of 3.3 +/- 1.77 mm and defect fill of 3.47 +/- 0.53 mm were noted in the PRP/BG group, with 3.29 +/- 1.68, 2.86 +/- 1.56 and 3.36 +/- 0.55 mm improvements, respectively, noted for the BG group. None of the differences between the two treatment modalities were statistically significant.

CONCLUSIONS

It is suggested that both PRP/BG combination and BG alone are effective in the treatment of intra-bony defects. The results also showed that using PRP with BG has no additional benefit in the reduction of pocket depth, clinical attachment gain and defect fill.

Four-year results of a prospective-controlled clinical study evaluating healing of intra-bony defects following treatment with an enamel matrix protein derivative alone or combined with a bioactive glass

AIM

To evaluate the 4-year results following regenerative periodontal surgery at intra-bony defects with either a combination of an enamel matrix protein derivative (EMD) and a bioactive glass (BG) or with EMD alone.

METHODS

Twenty-five patients with one deep intra-bony defect each were randomly treated with either an EMD+BG (test) or with EMD alone (control). Measurements were recorded at baseline, at 1 and at 4 years following therapy. The primary outcome variable was the clinical attachment level (CAL).

RESULTS

The test group demonstrated a mean CAL change from 10.3+/-1.6 to 6.7+/-1.2 mm (p<0.001) and to 6.9+/-1.0 mm (p<0.001) at 1 and 4 years, respectively. No statistically significant differences were found between the 1- and 4-year results. The control group showed a mean CAL change from 10.4+/-1.6 to 6.7+/-1.1 mm (p<0.001) at 1 year and 7.0+/-0.9 mm (p<0.001) at 4 years. The CAL change between 1 and 4 years did not present statistically significant differences. In each of the two groups, four defects have lost 1 mm of the CAL gained at 1 year. A CAL gain of 1 mm compared with the 1-year results was measured in only one defect of the test group. Compared with baseline, a CAL gain of >/=3 mm was found at 4 years in 10 defects in both groups. Between the treatment groups, no statistically significant differences in any of the investigated parameters were observed at 1 and at 4 years.

CONCLUSIONS

Within their limits, the present results indicate that the clinical improvements obtained with both regenerative modalities can be maintained over a period of 4 years.

Bonded indirect restorations for posterior teeth: from cavity preparation to provisionalization

Classic bonded indirect ceramic or resin composite restorations necessitate at least 2 appointments. The present article describes an updated technique for the first appointment comprising cavity preparation, dentin sealing, impression, and provisionalization. Two clinical cases are presented to illustrate the procedures step by step.

Histological findings of long-term healing of the experimental defects by application of a synthetic biphasic ceramic in rats

Calcium phosphate ceramics are generally biocompatible and can develop interactions with human recipient bone. Therefore, they can be widely used in the field of periodontology and dentistry. The purpose of this investigation was to assess the long-term histological bone healing results of experimentally created critical size parietal bone defects in rats. Twelve Wistar rats were used in this investigation. Two 6-mm wide, symmetrical, and circular critical size defects were created in each parietal bone of the animals. While the right defects filled with granular implant (Ceraform), the symmetrical defects were taken as controls. Eighteen months after implantation, rats were killed and defects including the biomaterial with surrounding bone was taken for histological examination. Serial histological sections were cut across the defects and stained for the histological analysis. Both control and Ceraform implanted regions contained dense collagenous tissue. In the implantation site, multinuclear giant cells were observed around the material. On the other hand, there were no necrosis, tumour, and infection in the implantation region. There was no statistical difference between the control and ceraform implanted groups when the bone formation results were compared (p > 0.05). In conclusion, the results revealed that this material is biocompatible and does enhance the new bone building despite the long-term observation period. Although this biphasic ceramic shows within the limits of the study as a less resorptive and not osteoconductive properties, it can be considered as a biocompatible bone defect filling material having a limited application alternative in dentistry and medicine.

Autologous iliac crest bone graft: should it still be the gold standard for treating nonunions?

Nonunion is a common complication following long-bone fracture, with a prevalence that ranges from 2.5-46%, depending on the location and severity of the injury to the bone, soft tissue, and vascular structures. The treatment of nonunions involves addressing the biology of fracture repair and the mechanical stability of fracture fixation, which are interrelated. Nonunion treatment has traditionally included the addition of autograft from the iliac crest to enhance healing. However, there an associated morbidity with the harvesting of the graft, and alternatives such as bone marrow aspirate, platelet-rich plasma, allograft, and ceramics have also been studied. In addition, new advances in the understanding of the cellular and molecular mechanisms of fracture repair have led to the use of growth factors, such as bone morphogenetic proteins, to accelerate bone healing. This article reviews the benefits of iliac crest bone graft relative to those of other modalities in the treatment of nonunions.

Platelet-rich plasma improves expansion of human mesenchymal stem cells and retains differentiation capacity and in vivo bone formation in calcium phosphate ceramics

INTRODUCTION

Mesenchymal stem cells (MSC) applied to bone substitution materials can improve bone healing. Bone formation in biocomposites is highly dependent on the kind of biomaterial, its pre-treatment and the applied cells. Potentially immunogenic or infectious supplements such as fetal calf serum (FCS) should be avoided in cell expansion media. Therefore, we developed an expansion protocol free of xenogenic supplements. Cells expanded with two different media were tested on distinct biomaterials for their bone formation capacity after ectopic implantation in vivo, as well as for their growth rate and differentiation capacity in vitro.

METHODS

MSC of six donors were expanded with cell expansion medium containing FCS (2%) or platelet-rich plasma (PRP, 3%). Their growth rate and osteogenic, adipogenic and chondrogenic differentiation capacity were compared in vitro. For the in vivo bone formation assay, expanded cells (2 x 105 or 2 x 106) were seeded on calcium-deficient hydroxyapatite (CDHA; n = 12) and on beta-tricalcium phosphate (beta-TCP; n = 12) blocks, which had been coated with either fibronectin or human serum. They were then implanted subcutaneously in severe combined immunodeficient mice (SCID), harvested after 8 weeks and analysed by histology. Bone formation was assessed by a semi-quantitative bone score, after toluidine blue and alizarin red staining. Human cells were detected by an in situ hybridisation for human-specific alu sequences.

RESULTS

PRP-supplemented expansion medium yielded two-fold higher cell numbers compared to medium with FCS (P = 0.046) after 3 weeks (four passages) and retained a similar capacity to differentiate towards the osteogenic, chondrogenic and adipogenic lineage. In vivo bone formation was equal for cells expanded with PRP and FCS and depended on the specific surface area of the carrier. CDHA (specific surface area (SSA) 48 m2/g) showed a significantly better bone formation in deep layers (P = 0.005) than beta-TCP (SSA 0.5 m2/g). Fibronectin-coating of the ceramics was slightly superior to coating with human serum (P = 0.045).

CONCLUSIONS

The replacement of FCS by PRP eliminated risks connected with the use of xenogeneic supplements. It improved expansion of MSC and retained their differentiation and in vivo bone formation capacity in a setting adaptable to autogenous use.

Anterior decompression via a wide transvertebral approach and a ceramic insert in a patient with cervical degenerative disease

BACKGROUND

The transvertebral approach is useful for decompression in patients with cervical radiculopathy; because the intervertebral disk is preserved, moveability is retained. We performed wide deletion of the vertebral body to increase the patient population eligible for treatment with this approach and include patients with compression of the cervical spinal cord.

METHODS

In patients undergoing anterior decompression, we performed vertebrotomy (13 x 8 mm) at the midline of the cervical vertebral body at the upper level using a surgical saw. The resulting hole facilitates decompression of the cervical cord and nerve root; a ceramic insert is introduced in the area of deletion. To prevent graft extrusion, the bilateral wings of the bone graft are fastened with bioabsorbable screws.

RESULTS

We used this approach in 163 patients with several cervical diseases. Collapse of the vertebral body and fusion of the operated intervertebral disk were encountered in only 1 patient (0.61%). There was no significant difference between pre- and postoperative alignment. Reoperation was required in 7 patients whose symptoms did not improve, in 1 with disk hernia, in 5 with severe spondylosis, and in 1 with combined-type OPLL.

CONCLUSIONS

Although this approach is appropriate in patients undergoing cervical anterior decompression, the narrowness of the visual field may result in insufficient decompression, and its indication is restricted to patients with cervical disk hernia, mild cervical spondylosis, and segmental OPLL. In patients with segmental instability, continuous or combined OPLL, severe cervical spondylosis, and kyphosis, this approach should not be used.

Osteogenic properties of calcium phosphate ceramics and fibrin glue based composites

Calcium phosphate (Ca-P) ceramics are currently used in various types of orthopaedic and maxillofacial applications because of their osteoconductive properties. Fibrin glue is also used in surgery due to its haemostatic, chemotactic and mitogenic properties and also as scaffolds for cell culture and transplantation. In order to adapt to surgical sites, bioceramics are shaped in blocks or granules and preferably in porous forms. Combining these bioceramics with fibrin glue provides a mouldable and self-hardening composite biomaterial. The aim of this work is to study the osteogenic properties of this composite material using two different animal models. The formation of newly formed bone (osteoinduction) and bone healing capacity (osteconduction) have been study in the paravertebral muscles of sheep and in critical sized defects in the femoral condyle of rabbits, respectively. The different implantations sites were filled with composite material associating Ca-P granules and fibrin glue. Ca-P granules of 1-2 mm were composed with 60% of hydroxyapatite and 40% of beta tricalcium phosphate in weight. The fibrin glue was composed of fibrinogen, thrombin and other biological factors. After both intramuscular or intraosseous implantations for 24 weeks and 3, 6, 12 and 24 weeks, samples were analyzed using histology and histomorphometry and mechanical test. In all cases, the newly formed bone was observed in close contact and around the ceramic granules. Depending on method of quantification, 6.7% (with BSEM) or 17% (with micro CT) of bone had formed in the sheep muscles and around 40% in the critical sized bone rabbit defect after 24 weeks. The Ca-P/fibrin material could be used for filling bone cavities in various clinical indications.

Conservative restorative treatment using a single-visit, all-ceramic CAD/CAM system

Computer-aided design/computer-aided manufacturing (CAD/CAM) continues to radically change the way in which the dental team plans, prepares, and fabricates a patient's restoration. This advancing technology offers the clinician the ability to scan the patient's failing dentition and then designs a long-lasting, reliable restoration based on this data. CAD/CAM systems also permit efficient, single-visit placement of the restoration while preserving much of the natural tooth structure. This article discusses how a chairside CAD/CAM system can be used to provide such a restoration in the posterior region in a single-visit.

Bone regeneration of porous β-tricalcium phosphate (Conduit™ TCP) and of biphasic calcium phosphate ceramic (Biosel®) in trabecular defects in sheep

In this study bone regeneration between porous beta-tricalcium phosphate (Conduit TCP) and biphasic calcium phosphate ceramic (Biosel), with a hydroxyapatite/beta-TCP ratio of 75/25, was compared. The ceramic particles were implanted in sheep trabecular bone for 3, 12, and 26 weeks. Histomorphometrical analysis revealed that Conduit degraded significantly during time and only 36% of the material was left at 26 weeks implantation time. Biosel, in contrast, remained nearly intact. The degradation of Conduit was due to dissolution as well as cell-mediated. Biosel showed a high cellular intervention, although this material did not degrade. Both materials were osteoconductive. The amount of newly formed bone appeared greater in the Conduit group after 26 weeks (46% +/- 8% as compared to 37% +/- 8% for Biosel), but this difference was not significant. Bone distribution over the defect was homogeneous in Conduit, whereas Biosel showed significantly more bone in the periphery of the defect after 26 weeks in comparison to the center. In conclusion, both ceramics are biocompatible and osteoconductive. Degradation showed a difference in amount and in cellular events, with more degraded Conduit TCP with less cellular intervention as compared to Biosel.

[Establishment of an experimental animal model with alveolar bone defect by surgery in rats]

PURPOSE

To establish an animal model for experimental study of orthodontic treatment of alveolar bone defect and other relative research.

METHODS

The experiment was carried out on forty SPF female Wistar rats,which were 6 weeks old. With the rats anaesthetized, one side of the alveolar bone in the maxillary first molar of the rats was removed partly. The defects were filled with Bio-glass. The tissue slices from the defects were observed under light microscope 2 weeks after surgery.

RESULTS

Only one of the forty rats was infected after operation, and the survival rate was 97.5%. The wounds of the survived rats healed well, and new bone was found around the Bio-glass 2 weeks after operation.

CONCLUSION

Animal model of alveolar bone defect established by surgery is simple and reliable, which can be used for further studies. Supported by National Natural Science Foundation of Shandong Province (Grant No.Y2004C13) and Medical Science and Technology Enhancement Award Project of Shangdong Province (Grant No.2005H2038).

Molecular basis for action of bioactive glasses as bone graft substitute

Bone grafting procedures are undergoing a major shift from autologous and allogeneic bone grafts to synthetic bone graft substitutes. Bioactive glasses are a group of synthetic silica-based bioactive materials with bone bonding properties first discovered by Larry Hench. They have several unique properties compared with other synthetic bioresorbable bioactive ceramics, such as calcium phosphates, hydroxyapatite (HA) and tricalcium phosphate (TCP). Bioactive glasses have different rates of bioactivity and resorption rates depending on their chemical compositions. The critical feature for the rate of bioactivity is a SiO2 content < 60% in weight. In vivo, the material is highly osteoconductive and it seems to promote the growth of new bone on its surface. In a recent study, the activity of the material was found even to overshadow the effect of BMP-2 gene therapy. In vivo, there is a dynamic balance between intramedullary bone formation and bioactive glass resorption. Recent studies of molecular biology have shown that bioactive glass induces a high local turnover of bone formation and resorption. Many osteoporotic fracture patients are candidates for concurrent treatment with bisphosphonates and bioceramic bone graft substitutes. Since osteopromotive silica-based bioactive glasses induce accelerated local bone turnover, adjunct antiresorptive agents may affect the process. However, a recent study showed that an adjunct antiresorptive therapy (zoledronic acid) is even beneficial for bone incorporation of bioactive glass. Based on these observations, bioactive glasses are a promising group of unique biomaterials to act as bone graft substitutes.

Comparison of platelet pellet and bioactive glass in periodontal regenerative therapy

OBJECTIVE

In recent years, platelet-rich plasma combined with graft materials has been used for periodontal regeneration. The individual role of blood products with guided tissue regeneration in periodontal regenerative therapy is unclear and needs to be elucidated. The purpose of this study was to compare the clinical and radiological effectiveness of platelet pellet/guided tissue regeneration (PP/GTR) and bioactive glass/GTR (BG/GTR) treatments in patients with periodontal disease.

MATERIAL AND METHODS

Using a split mouth design, 15 chronic periodontitis patients with pocket depths > or = 6 mm following periodontal initial therapy were randomly assigned to treatment with a combination of PP/GTR or BG/GTR in contralateral dentition areas. An absorbable membrane of polylactic acid was used GTR. The criteria for the comparative study were preoperative and postoperative 6 months pocket depth, clinical attachment level, and radiological alveolar bone level.

RESULTS

Both treatment modalities resulted in significant pocket depth reduction and gain in clinical attachment and alveolar bone level compared to the preoperative values (p < 0.01). Reduction in pocket depth, gain in clinical attachment and alveolar bone level were 4(3-6), 4.1+/-0.7, 4.9+/-1.4 mm in the PP/GTR group and 4(3-7), 4.1+/-1.2, 5.9+/-1.7 mm in the BG/GTR group, respectively. The differences between the two groups were not statistically significant (p > 0.05).

CONCLUSIONS

Within the limits of this study, it was concluded that PP may be effective as a bioactive glass graft material and used as a graft material for treating intrabony defects. PP thus appears to be a suitable alternative in the regenerative treatment of intrabony periodontal defects.