Clinical Evaluation of Calcium Sulfate in Combination With Demineralized Freeze-Dried Bone Allograft for the Treatment of Human Intraosseous Defects

The Use of Biocompatible Membranes in Oral Surgery: The Past, Present & Future Directions. A Narrative Review

The use of biocompatible membranes in periodontal and oral surgery is an important part of regeneration. Over the years, several different membranes have been developed, ranging from non-resorbable membranes that have to be removed in a separate procedure, to collagen membranes that completely resorb on their own, thus avoiding the need for a second surgery. Autogenous membranes are becoming increasingly popular in more recent years. These membranes can be used with a great variety of techniques in the four main hard tissue regenerative procedures: guided tissue regeneration, alveolar ridge preservation, guided bone regeneration and sinus floor augmentation. A review of the literature was conducted in order to identify the most commonly used membranes in clinical practice, as well as the most promising ones for regeneration procedures in the future. The information provided in this review may serve as a guide to clinicians, in order to select the most applicable membrane for the clinical case treated as the correct choice of materials may be critical in the procedure's success.

Role of Biomaterials Used for Periodontal Tissue Regeneration—A Concise Evidence-Based Review

Periodontal infections are noncommunicable chronic inflammatory diseases of multifactorial origin that can induce destruction of both soft and hard tissues of the periodontium. The standard remedial modalities for periodontal regeneration include nonsurgical followed by surgical therapy with the adjunctive use of various biomaterials to achieve restoration of the lost tissues. Lately, there has been substantial development in the field of biomaterial, which includes the sole or combined use of osseous grafts, barrier membranes, growth factors and autogenic substitutes to achieve tissue and bone regeneration. Of these, bone replacement grafts have been widely explored for their osteogenic potential with varied outcomes. Osseous grafts are derived from either human, bovine or synthetic sources. Though the biologic response from autogenic biomaterials may be better, the use of bone replacement synthetic substitutes could be practical for clinical practice. This comprehensive review focuses initially on bone graft replacement substitutes, namely ceramic-based (calcium phosphate derivatives, bioactive glass) and autologous platelet concentrates, which assist in alveolar bone regeneration. Further literature compilations emphasize the innovations of biomaterials used as bone substitutes, barrier membranes and complex scaffold fabrication techniques that can mimic the histologically vital tissues required for the regeneration of periodontal apparatus.

Predictability and Clinical Stability of Barrier Membranes in Treatment of Periodontal Intrabony Defects: A Systematic Review and Meta-Analysis

The adjunctive use of GTR membranes helps us to achieve predictable periodontal regeneration. The aim of this systematic review was to evaluate and compare the treatment efficacy of resorbable versus non-resorbable barrier membranes used in guided tissue regeneration in the treatment of intrabony defects in chronic periodontitis patients. The following databases were searched: Medline, the Cochrane Central Register of Controlled Trails (CENTRAL), SCOPUS, EMBASE. Randomized clinical trials (RCTs) published in English languages over the past 25 years were included. The primary outcomes assessed were: change of probing pocket depth (PD), change in clinical attachment level (CAL) and gingival recession coverage (GRC), and intrabony defect fill (IBDF). A total of eight RCTs were included for systematic review. The outcome of GR at a six-month interval revealed a significant difference in treatment effect with a mean difference of 0.42, 95% CI [0.02, 0.81]; Z = 2.09, (p = 0.04) favouring the resorbable membrane group. The intrabony defect depth fill at a 12-month interval revealed a significant difference in treatment effect with MD of 0.79, p = 0.00001; favoring the resorbable membrane group. The resorbable membrane showed a significant improvement in gingival recession coverage and intrabony defect fill, owing to its advantage of avoiding the second surgical intervention.

The use of nanocrystalline and two other forms of calcium sulfate in the treatment of infrabony defects: A clinical and radiographic study

Background:

Calcium sulphate(CS) is one of the oldest alloplastic graft materials used because of its biocompatibility, handling characteristics, porosity, different rates of dissolution, chemico-physical resemblance to bone mineral, ability to induce release of growth factors and potentially unlimited supply at a modest cost. Aim of the study was to evaluate the efficacy of 3 forms of calcium sulphate i.e. Nanogen (nCS)(+), BoneGen(+) and Dentogen(+) in treatment of infrabony defects and to compare their efficacy as bone grafting substitutes.

Materials and Methods:

A prospective randomized, double blind controlled study was conducted on 45 sites from 16 subjects having Moderate to Advanced Periodontitis who were divided into 3 groups i.e. Group I (Nanogen), Group II (Dentogen) and Group III (BoneGen) clinical along with radiographic measurements were taken at baseline, 6 and 12 months postoperatively.

Results:

There was no significant inter-group difference in mean clinical attachment level (CAL) values at different time intervals whereas Intra-group changes in CAL at 6 and 12 months as compared to baseline were significant statistically. In Group I, changes in CAL between 6 and 12 months were found to be statistically significant in comparison with Group II and III.

Conclusion:

Both Nanogen and BoneGen TR can be considered valuable options in the treatment of infra-bony periodontal defects. The faster degradation of Dentogen may negatively affect its bone regeneration potential.

Clinical Evaluation of 262 Osseointegrated Implants Placed in Sites Grafted With Calcium Phosphosilicate Putty: A Retrospective Study

Along with the widespread use of dental implants, regenerative procedures have become an indispensable tool for implant surgeons in managing residual ridges and the surrounding bone. Putty bone grafts have significantly superior handling characteristics in comparison to particulates. These include ease of placement, enhanced particle containment, and a viscous consistency that has allowed for unique delivery systems to be developed. The aim of this study was to report the clinical efficacy of calcium phosphosilicate (CPS) putty in a wide variety of indications related to implant reconstruction and to report the survival rate of implants placed in these grafted sites. The CPS putty was used as the graft material of choice. Treatments were categorized into following groups: extraction graft, extraction with immediate implant placement, all-on-four concept, peri-implantitis treatment, bone augmentation before implant placement, implant replacement graft, and grafting around implant placed in resorbed ridges. Included in the analysis were 65 patients (36 men, 29 women) with a mean age of 63 ± 12 years. In total, 262 implants were placed. Four implants were diagnosed with peri-implantitis and were treated as described in category 4, for a total of 266 grafted sites. Two implants from the extraction graft category and 3 implants from the all-on-four group were lost and replaced with successfully osseointegrated implants during a mean study follow-up period of 12.24 ± 2.32 months. The implant success rate at 1 year was 98.1% (257/262). Based on results of this large-scale, retrospective study we conclude that (1) the use of putty bone grafts can simplify bone-grafting procedures and reduce intraoperative time in various grafting indications, (2) this study verified the efficacy of a CPS putty bone graft biomaterial in a large array of implant-related surgical indications, and (3) implants placed in sites grafted with CPS putty yield very high survival rates.

Biologic response of local hemostatic agents used in endodontic microsurgery

Appropriate use of local hemostatic agent is one of the important factors on the prognosis of endodontic microsurgery. However, most investigations to date focus on the hemostatic efficacy of the agents, whereas their biologic characteristics have not received enough attention. The purpose of this paper was to review the biologic response of local hemostatic agents, and to provide clinical guidelines on their use during endodontic microsurgery. Electronic database (PUBMED) was screened to search related studies from 1980 to 2013, and 8 clinical studies and 18 animal studies were identified. Among the materials used in these studies, most widely-investigated and used materials, epinephrine, ferric sulfate (FS) and calcium sulfate (CS), were thoroughly discussed. Influence of these materials on local tissue and systemic condition, such as inflammatory and foreign body reaction, local ischemia, dyspigmentation, delayed or enhanced bone and soft tissue healing, and potential cardiovascular complications were assessed. Additionally, biological property of their carrier materials, cotton pellet and absorbable collagen, were also discussed. Clinicians should be aware of the biologic properties of local hemostatic agents and their carrier materials, and should pay attention to the potential complications when using them in endodontic microsurgery.

Biomaterials for periodontal regeneration: a review of ceramics and polymers

Periodontal disease is characterized by the destruction of periodontal tissues. Various methods of regenerative periodontal therapy, including the use of barrier membranes, bone replacement grafts, growth factors and the combination of these procedures have been investigated. The development of biomaterials for tissue engineering has considerably improved the available treatment options above. They fall into two broad classes: ceramics and polymers. The available ceramic-based materials include calcium phosphate (eg, tricalcium phosphate and hydroxyapatite), calcium sulfate and bioactive glass. The bioactive glass bonds to the bone with the formation of a layer of carbonated hydroxyapatite in situ. The natural polymers include modified polysaccharides (eg, chitosan,) and polypeptides (collagen and gelatin). Synthetic polymers [eg, poly(glycolic acid), poly(L-lactic acid)] provide a platform for exhibiting the biomechanical properties of scaffolds in tissue engineering. The materials usually work as osteogenic, osteoconductive and osteoinductive scaffolds. Polymers are more widely used as a barrier material in guided tissue regeneration (GTR). They are shown to exclude epithelial downgrowth and allow periodontal ligament and alveolar bone cells to repopulate the defect. An attempt to overcome the problems related to a collapse of the barrier membrane in GTR or epithelial downgrowth is the use of a combination of barrier membranes and grafting materials. This article reviews various biomaterials including scaffolds and membranes used for periodontal treatment and their impacts on the experimental or clinical management of periodontal defect.

A comparative evaluation of the effectiveness of guided tissue regeneration by using a collagen membrane with or without decalcified freeze-dried bone allograft in the treatment of infrabony defects: A clinical and radiographic study

BACKGROUND

The present, randomized, controlled clinical and radiographic study was undertaken to compare the effectiveness of guided tissue regeneration (GTR) by using a collagen membrane barrier with or without decalcified freeze-dried bone allograft (DFDBA) in the treatment of periodontal infrabony defects characterized by unfavorable architecture.

MATERIALS AND METHODS

Sixteen systemically healthy patients with 20 periodontal infrabony defects were selected for the study. Each patient had at least ≥ 5 mm clinical probing pocket depth (PPD) at the selected site and depth of intrabony component ≥ 3 mm as assessed by clinical and radiographic measurements. Baseline measurements included plaque index, papillary bleeding index, PPD, gingival recession, clinical attachment level and radiographic defect depth (DD). At the time of surgery, the defects were randomly assigned to either the test group (collagen membrane plus DFDBA) or the control group (collagen membrane only).

RESULTS

At the 6-month examination, PPPD reduction was significantly greater in the GTR + DFDBA group (4.06 ± 0.38 mm) compared with the GTR group (3.2 ± 0.74 mm). The mean gains of clinical attachment were 3.54 ± 0.36 mm in the test group and 2.50 ± 0.74 mm in the control group. Radiographic DD reduction was similarly greater in the GTR + DFDBA group (2.40 ± 0.51 mm) compared with the GTR group (1.60 ± 0.51 mm).

CONCLUSIONS

The results of the present study indicate that the use of a GTR membrane with bone graft has significantly improved all clinical parameters tested as compared with the use of bioresorbable membrane alone in the treatment of infrabony defects characterized by unfavorable architecture.

Clinical and radiographic evaluation of demineralized bone matrix (grafton) as a bone graft material in the treatment of human periodontal intraosseous defects

PURPOSE

The purpose of this clinical trial was to evaluate the efficacy of demineralized bone matrix (DBM) as a bone graft material in the treatment of human intrabony periodontal defects as compared with control defects treated by open flap debridement (OFD) alone.

MATERIALS AND METHODS

A controlled clinical trial was carried out for a period of 9 months in 11 patients (4 males and 7 females) with an age group of 25-50 years, contributing to a total of 30 defects. The selected defects were then randomly divided in to experimental sites (OFD + DBM) and control sites (OFD alone). Probing depth, clinical attachment levels and position of the gingival margin were recorded at baseline 3, 6 and 9 months post-operatively. Standardized radiographs (parallel technique) were also documented at these recall intervals.

RESULTS

On completion of 9 months, the mean percentage of probing depth reduction achieved in the experimental sites and control sites was 61.70%, 23.86% respectively. The mean percentage of clinical attachment level gain was 61.34% and 19.37% in the experimental and control sites respectively. In the experimental sites recession was observed to a lesser extent.

CONCLUSION

The use of DBM was more effective than OFD in improving clinical parameters and radiographic bone fill as shown in the present study. However, there is a need for further long term studies.

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.

Evaluation of calcium sulphate barrier to collagen membrane in intrabony defects

PURPOSE

The aim of this study was to clinically and radiographically evaluate and compare treatment of intrabony defects with the use of decalcified freeze-dried bone allograft in combination with a calcium sulphate barrier to collagen membrane.

METHODS

Twelve patients having chronic periodontal disease aged 20 to 50 years and with a probing depth >6 mm were selected. Classification of patient defects into experimental and control groups was made randomly. In the test group, a calcium sulphate barrier membrane, and in control group, a collagen membrane, was used in conjunction with decalcified freeze-dried bone graft in both sides. Ancillary parameters as well as soft tissue parameters along with radiographs were taken at baseline and after 6 months of surgery. Parameters assessed were plaque index, modified gingival index, probing depth, relative attachment level, and location of the gingival margin. A Student's t-test was done for intragroup and a paired t-test for intergroup analysis.

RESULTS

Intragroup analysis revealed statistically significant improvement in all the ancillary parameters and soft tissue parameters with no statistically significant difference in intergroup analysis.

CONCLUSIONS

The study concluded that a calcium sulphate barrier was comparable to collagen membrane in achieving clinical benefits and hence it can be used as an economical alternative to collagen membrane.

The in vitro elution of BMP-7 from demineralized bone matrix

Demineralized bone matrix (DBM) grafts induce new bone formation by locally releasing matrix-associated growth factors, such as bone morphogenetic proteins (BMPs), to the surrounding tissue after implantation. However, the release kinetics of BMPs from DBM lack characterization. Such information can potentially help to improve processing techniques to maximize graft osteoinductive potential, as well as increase understanding of the osteoinductive process itself. We produced DBM with three particle size ranges from bovine cortical bone, i.e., <106, 106-300, and 300-710 μm and extracted 1.5 g of each size range in 40 ml of Sorensen's buffer at room temperature for up to 168 h. The BMP-7 concentration of the DBM and the buffer were measured at each time point using enzyme-linked immunosorbant assay. Based on measurement of the concentration of BMP-7 in the buffer, the 0-8 h elution rate was high, i.e., 3.3, 2.9, and 2.2 ng BMP-7/g DBM h, and for the 8-168 h interval was much lower, at 0.039, 0.15, and 0.11 ng BMP-7/g DBM h for the three size ranges, respectively. By 168 h, there was no indication that elution was nearing completion. Measurement of the residual BMP-7 remaining in the DBM as a function of time yielded unexpected results, i.e., after the BMP-7 content of the DBM declined for the first 4-6 h, it paradoxically increased for the remaining interval. We propose a two-compartment model to help explain these results in terms of the possible distribution of BMP-7 in bone matrix.

Bone Repair in Periodontal Defect Using a Composite of Allograft and Calcium Sulfate (DentoGen) and a Calcium Sulfate Barrier

Deep bone defects are caused by the progression of periodontal disease, which breaks down bone and connective tissue that hold teeth in place. In this case, a 37-year-old male patient presented a deep bone defect with advanced periodontal disease around an upper canine. Medical-grade calcium sulfate was mixed with demineralized freeze-dried bone allograft and used to repair and regenerate the defect. Analysis of the radiographs at the 5-month time point showed the bone had completely regenerated.

Digital subtraction radiographic analysis of the combination of bioabsorbable membrane and bovine morphogenetic protein pool in human periodontal infrabony defects

OBJECTIVES

This study assessed the bone density gain and its relationship with the periodontal clinical parameters in a case series of a regenerative therapy procedure.

MATERIAL AND METHODS

Using a split-mouth study design, 10 pairs of infrabony defects from 15 patients were treated with a pool of bovine bone morphogenetic proteins associated with collagen membrane (test sites) or collagen membrane only (control sites). The periodontal healing was clinically and radiographically monitored for six months. Standardized pre-surgical and 6-month postoperative radiographs were digitized for digital subtraction analysis, which showed relative bone density gain in both groups of 0.034 ± 0.423 and 0.105 ± 0.423 in the test and control group, respectively (p>0.05).

RESULTS

As regards the area size of bone density change, the influence of the therapy was detected in 2.5 mm² in the test group and 2 mm² in the control group (p>0.05). Additionally, no correlation was observed between the favorable clinical results and the bone density gain measured by digital subtraction radiography (p>0.05).

CONCLUSIONS

The findings of this study suggest that the clinical benefit of the regenerative therapy observed did not come with significant bone density gains. Long-term evaluation may lead to a different conclusions.

Bone Regeneration Using B-Tricalcium Phosphate in a Calcium Sulfate Matrix

The aim of the study was the histomorphometric comparison of the osteogenic potential of β-tricalcium phosphate (β-TCP) alone or in a calcium sulfate matrix. Three round defects, 10 mm (diameter) × 5 mm (depth), were created on each iliac crest of 4 dogs. The defects were divided into 3 groups. Ten defects were filled with β-TCP in a calcium sulfate (CS) matrix (Fortoss Vital; group A), 10 defects were filled with β-TCP alone (Fortoss Resorb; group B), and 4 defects were left ungrafted to heal spontaneously (group C). All defects were left to heal for 4 months without the use of a barrier membrane. Histologic evaluation and morphometric analysis of undecalcified slides was performed using the areas of regenerated bone and graft remnants. All sites exhibited uneventful healing. In group A sites (β-TCP/CS), complete bone formation was observed in all specimens, graft granules dominated the area, and a thin bridge of cortical bone was covering the defect. Group B (β-TCP) defects were partially filled with new bone, the graft particles still dominated the area, while the outer cortex was not restored. In the ungrafted sites (group C), incomplete new bone formation was observed. The outer dense cortical layer was restored in a lower level, near the base of the defect. The statistical analysis revealed that the mean percentage of new bone regeneration in group A was higher than in group B (49.38% and 40.31%, respectively). A statistically significant difference existed between the 2 groups. The beta-TCP/CS group exhibited significantly higher new bone regeneration according to a marginal probability value (P = .004 &lt; .05). The use of β-TCP in a CS matrix produced significantly more vital new bone fill and preserved bone dimensions compared with the use of β-TCP alone.

Calcium sulfate–carboxymethylcellulose bone graft binder: Histologic and morphometric evaluation in a critical size defect

Calcium sulfate (CS) is widely used as a bone graft binder and expander. Recent reports indicate that carboxymethylcellulose (CMC) can improve the clinical properties of CS when used as binder for particulate bone grafts; however, limited information is available on the effects of CMC on bone regeneration. The purpose of this study was to evaluate the histologic and morphometric characteristics of bone formation in calvarial defects grafted with a CS-based putty containing 10% CMC in combination with allogeneic demineralized bone matrix (DBM). Bone formation and graft/binder resorption were compared with a surgical grade CS and DBM in paired critical-sized calvarial defects in 25 Wistar rats (350-450 g). Six animals each provided paired defects at 7, 14, 21, and 28 days postsurgery for nondecalcified processing and microscopic analysis. Defects grafted with CS or CS-CMC putty as the DBM binder exhibited similar patterns and proportions of bone formation, fibrous tissue/marrow, and residual DBM particles. Comparable mean +/- SD proportions of new bone formation (31.7 +/- 9.5 and 33.7 +/- 12.9), fibrous tissue/marrow (54.2 +/- 8.3 and 53.0 +/- 10.8), residual DBM particles (8.3 +/- 6.8 and 10.1 +/- 6.3), and residual binder material (5.5 +/- 4.6 and 3.7 +/- 3.5) were found at 28 days for defects grafted with CS and CS-CMC putty, respectively. Thus, CMC was found to improve the handling characteristics of CS and, when used in conjunction with DBM, supported comparable levels bone formation and patterns of binder/scaffold resorption as CS and DBM in a calvarial defect model.

Autogenous Bone Graft With or Without a Calcium Sulfate Barrier in the Treatment of Class II Furcation Defects: A Histologic and Histometric Study in Dogs

BACKGROUND

The purpose of this study was to histologically evaluate the healing of surgically created Class II furcation defects treated using an autogenous bone (AB) graft with or without a calcium sulfate (CS) barrier.

METHODS

The second, third, and fourth mandibular premolars (P2, P3, and P4) of six mongrel dogs were used in this study. Class II furcation defects (5 mm in height x 2 mm in depth) were surgically created and immediately treated. Teeth were randomly divided into three groups: group C (control), in which the defect was filled with blood clot; group AB, in which the defect was filled with AB graft; and group AB/CS, in which the defect was filled with AB graft and covered by a CS barrier. Flaps were repositioned to cover all defects. The animals were euthanized 90 days post-surgery. Mesio-distal serial sections were obtained and stained with either hematoxylin and eosin or Masson's trichrome. Histometric, using image-analysis software, and histologic analyses were performed. Linear and area measurements of periodontal healing were evaluated and calculated as a percentage of the original defect. Percentage data were transformed into arccosine for statistical analysis (analysis of variance; P <0.05).

RESULTS

Periodontal regeneration in the three groups was similar. Regeneration of bone and connective tissue in the furcation defects was incomplete in most of the specimens. Statistically significant differences were not found in any of the evaluated parameters among the groups.

CONCLUSION

Periodontal healing was similar using surgical debridement alone, AB graft, or AB graft with a CS barrier in the treatment of Class II furcation defects.

Position Paper: Periodontal Regeneration

Untreated periodontal disease leads to tooth loss through destruction of the attachment apparatus and tooth-supporting structures. The goals of periodontal therapy include not only the arrest of periodontal disease progression,but also the regeneration of structures lost to disease where appropriate. Conventional surgical approaches (e.g., flap debridement) continue to offer time-tested and reliable methods to access root surfaces,reduce periodontal pockets, and attain improved periodontal form/architecture. However, these techniques offer only limited potential towards recovering tissues destroyed during earlier disease phases. Recently, surgical procedures aimed at greater and more predictable regeneration of periodontal tissues and functional attachment close to their original level have been developed, analyzed, and employed in clinical practice. This paper provides a review of the current understanding of the mechanisms, cells, and factors required for regeneration of the periodontium and of procedures used to restore periodontal tissues around natural teeth. Targeted audiences for this paper are periodontists and/or researchers with an interest in improving the predictability of regenerative procedures. This paper replaces the version published in 1993.