Immediate loading of the grafted maxillary sinus using platelet rich plasma and autogenous bone: a preliminary study with histologic and histomorphometric analysis

OBJECTIVE: The goal of this clinical study was to evaluate dental implant survival rates using the concept of a nonfunctional, immediate loading protocol with nonsplinted dental implants in the grafted maxillary sinus during a 52-week period. Random histomorphological and histomorphometric analysis was completed to evaluate the early healing effect of platelet rich plasma (PRP) and 50% autogenous bone combined with 3 different substitute graft materials. MATERIALS: Four to 8 months after grafting the sinus with PRP sprayed autogenous bone combined with 3 different substitute graft materials in a 50:50 composite ratio, 27 hydroxyapatite- coated dental implants were surgically placed in 41 patients and immediately loaded between 48 hours and 5 days later with custom titanium abutments and acrylic provisional restorations placed out of functional occlusion. Six months later, definitive ceramometal restorations were cemented on to the custom abutments. RESULTS: During a 52-week observation period, no implants were lost. Between 4 and 8 months of graft healing time, histologic and histomorphometric analysis revealed formation of new vital bone in different graft specimens ranging from 77% to 100%. CONCLUSION: The preliminary results of this clinical study indicate that immediate nonfunctional loading using PRP and 50% autogenous bone combined with different substitute graft materials is a predictable protocol in the grafted maxillary sinus as early as 4 months of postgrafting. The high implant survival rate is due to the early formation of large percentages of new vital bone as confirmed by using histologic and histomorphometric analysis.     

Eighteen-month radiographic and histologic evaluation of sinus grafting with anorganic bovine bone in the chimpanzee.

Maxillary sinus grafting procedures are currently the treatment of choice when the alveolar crest of the posterior maxilla is in close approximation to the maxillary sinus. The short-term histologic and radiographic healing following sinus grafting with natural bone mineral (Bio-Oss) in the chimpanzee has been evaluated. We have previously shown by histomorphometric and radiographic analysis that the percentage of vital bone area, the vertical height, and the density of new bone in the maxillary sinus was significantly greater with anorganic bovine bone compared to bovine Type I collagen matrix. The purpose of this in vivo study was to determine the bone mineral density (BMD) of the sinus grafts, the vertical height stability, the vital bone area, and the extent of anorganic bovine bone replacement 18 months postoperatively in 4 maxillary sinuses from 4 different animals. Radiographic analysis of computed tomographic scans taken at 1.5 years revealed an average BMD of 658 mg/mL, which was not significantly different from the values found at 6.5 months. The radiographic vertical height was maintained between the 6.5- and 18-month time points. On average, the grafts were found to have a height of 14 mm. Lateral wall biopsy specimens at 7.5 months were compared to those at 18 months. With the anorganic bovine bone treatment, the percentage of vital bone area increased from 62 +/- 3% to 70 +/- 7% and the percentage of natural bone mineral area decreased from 19 +/- 14% to 6 +/- 3%. The bovine Type I collagen matrix vital bone percentage at 7.5 months was 34 +/- 21%. These results demonstrate that sinus grafting with anorganic bovine bone maintains radiographic evidence of density and height stability of 1.5 years. In addition, histologic evidence supports the hypothesis that anorganic bovine bone is replaced by vital bone.     

Calvarial versus iliac crest for autologous bone graft material for a sinus lift procedure: a histomorphometric study

PURPOSE: The aim of this study was to compare, through histomorphometric analysis, the use of donor autogenous bone graft from calvarial or iliac sources for maxillary sinus lift procedures. MATERIALS AND METHODS: Sixteen patients requiring maxillary sinus augmentation were included in this study. One group of 10 patients was alternatively selected to receive autologous calvarial bone particles, and another group of 6 patients received autologous iliac bone particles. Five months after surgery, bone biopsy specimens were obtained at the time of implant procedure and analyzed through histomorphometry. To compare mean values between the calvarial and iliac crest groups, the Student t test was performed. The level for statistical significance was set at P < .05. RESULTS: All patients completed the healing period following sinus augmentation procedure without complications. In the calvarial group, an average total bone volume (BV) of 73.4% +/- 13.1% was found. Nonvital bone constituted an average of 5.5% +/- 6.3% of the total tissue volume. The percentage of vital bone (VB) showed an average of 67.9% +/- 16.1%. In the iliac group, the average total bone volume was 46.6% +/- 17.4%, with an average of 12.6% +/- 7.7% of NVB and an average of 34.0% +/- 21.5% of VB. A significant difference was observed between calvarial and iliac bone grafts with respect to BV, VB, and NVB (P < .05). CONCLUSION: From this present histomorphologic study, it might be concluded that grafted bone obtained from calvarial sources for sinus lift procedure presented a significantly higher degree of bone volume and vital bone volume in contrast to bone harvested from the iliac crest.     

A clinical and histologic evaluation of implant integration in the posterior maxilla after sinus floor augmentation with autogenous bone,bovine hydroxyapatite,or a 20:80 mixture

PURPOSE: This study was designed to clinically and histologically evaluate the integration of titanium implants in different grafting materials used for maxillary sinus augmentation procedures. MATERIALS AND METHODS: A total of 21 patients and 36 maxillary sinuses were augmented with (1) autogenous particulated bone from the mandibular ramus, (2) bovine hydroxyapatite (BH) with membrane coverage, or (3) an 80/20 mixture of BH and autogenous bone. The grafts were allowed to heal for 6 to 9 months prior to placement of microimplants for histology and standard implants for prosthetic rehabilitation. After another 6 months of healing, when abutments were connected, the microimplants were retrieved for histologic and morphometric analyses. The outcome of the standard implants was clinically evaluated after 1 year of loading. RESULTS: The mean bone-implant contact was 34.6 +/- 9.5%, 54.3 +/- 33.1%, and 31.6 +/- 19.1% for autogenous bone, mixture of 20% autogenous bone/80% BH, and 100% BH, respectively. The corresponding values for the bone area parameter were 37.7 +/- 31.3%, 39.9 +/- 8%, and 41.7 +/- 26.6%. The BH area was found to be 12.3 +/- 8.5% and 11.8 +/- 3.6% for 20% autogenous bone/80% BH and 100% BH, respectively. There were no statistically significant differences for any parameter between any of the groups. After 1 year of loading, 6 of the 33 implants placed in autogenous bone grafts, 2 of the 35 implants placed in the BH/autogenous bone mixture, and 2 of 43 implants placed in BH were lost. There were no statistically significant differences between any of the groups. DISCUSSION: The histomorphometric analysis showed no differences between the 3 groups, indicating that autogenous bone graft can be substituted with bovine hydroxyapatite to 80% or 100% when used for maxillary sinus floor augmentation. The effect of adding autogenous bone remains unclear but may allow for a reduction of the healing time. CONCLUSION: The results from this clinical and histologic study indicate that similar short-term results can be expected when using autogenous bone, BH, or a mixture of them for maxillary sinus floor augmentation and delayed placement of dental implants.     

Maxillary alveolar ridge reconstruction with monocortical fresh-frozen bone blocks: a clinical, histological and histomorphometric study

BackgroundThis investigation is a clinical and histological assessment of fresh-frozen bone use in the reconstruction of maxillary alveolar ridges. The study evaluates the effectiveness of this material as a bone filler prior the placement of dental implants.Patients and methodsSixteen patients with atrophic maxillary ridges underwent maxillary reconstruction with fresh-frozen tibial human block grafts prior to implant placement. Sampling procedures were carried out 4, 6 and 9 months later when a bone core was removed from the grafts for histological and histomorphometric analysis.ResultsEighteen blocks were placed, and each patient received either 1 or 2 blocks. During the sampling procedures, all of the grafts were found to be firm in consistency, well-incorporated, and vascularized. A total of 34 implants were placed into the grafts with a minimum of 40-Newton-cm torque in all cases. The follow-up period ranged from 18 to 30 months. No implants were lost. The histological analysis revealed vital bone with mature and compact osseous tissue surrounded by marrow spaces.ConclusionBone allografts can be used successfully as graft material for the treatment of maxillary ridge defects. This type of bone graft can be used safely in the areas of implant placement as a suitable alternative to autogenous grafts.     

A histologic and histomorphometric evaluation of anorganic bovine bone retrieved 9 years after a sinus augmentation procedure

BACKGROUND: Anorganic bovine bone (ABB) has been shown to have osteoconductive properties and no inflammatory or adverse responses as grafting materials used in sinus augmentation procedures. Despite these successful results, histologic data in humans over the long-term period are scarce. The purpose of this study was to analyze the histomorphometric data 9 years after surgery in a case of maxillary sinus augmentation using ABB. METHODS: The histologic evaluation was performed in five different thin sections of the specimen, comparing histomorphometric measures for newly formed bone, marrow spaces, biomaterial particles remnants, and number of osteocytes embedded in both trabecular bone and bone tissue near the ABB. The investigation was carried out by means of scanning electron microscopy and brightfield and circularly polarized light microscopy. RESULTS: We observed a mean amount of newly formed bone of 46.0% +/- 4.67%, ABB remnants of 16.0% +/- 5.89%, and marrow spaces of 38.0% +/- 8.93%. The osteocyte index was 4.43 for bone around ABB and 3.27 in the trabecular bone at a distance from the particles. CONCLUSIONS: After 9 years, the tissue pattern appeared composed by residual ABB particles in close contact to the newly formed bone. The bone mineralized matrix around the ABB had collagen fibers randomly oriented and more osteocytes embedded. The results demonstrate both a high level of osteoconductivity and a "biomimetic" behavior over the long term.     

Effect of platelet-rich plasma with autogenous bone graft for maxillary sinus augmentation in a rabbit model.

PURPOSE: To evaluate the effect of platelet-rich plasma (PRP) on autogenous bone graft remodeling during sinus augmentation in a rabbit model. MATERIALS: Twelve New Zealand White rabbits were divided randomly into 3 groups based on their time of sacrifice (2, 4, and 8 weeks). All animals underwent a general anesthetic and harvesting of an autogenous bone graft from the right iliac crest with subsequent bilateral maxillary sinus augmentation. PRP was prepared via standard approved technique by acquiring 21 cc of autogenous blood and performing differential centrifugation to obtain PRP. One cc of PRP was produced that was mixed with bovine topical thrombin and calcium chloride. The left maxillary sinus received only autogenous bone, while the right maxillary sinus received a mixture of PRP mixed with autogenous bone, thus each animal acted as its own control. Equal volumes of bone were inserted in each maxillary sinus. Animals were sacrificed at 2, 4, and 8 weeks and all specimens were harvested for peripheral quantitative computed tomography (pQ-CT), static, and dynamic and histomorphometric analysis. RESULTS: Student t tests were performed comparing bone density via pQ-CT analysis, histomorphometric parameters of total bone area, and bone apposition rate. PRP had no statistically significant effect on bone graft healing in maxillary sinus augmentation when compared using standard pQ-CT, static, and dynamic histologic criteria. CONCLUSION: This study fails to find a direct stimulatory effect of PRP on healing of autogenous bone grafts using pQ-CT, static, and dynamic histomorphometric analyses.     

Anatomic Site Evaluation of Edentulous Maxillae for Dental Implant Placement

Purpose This study evaluated 17 edentulous cadavers for bone quantity and quality of the alveolar process of the maxilla for the purpose of dental implant placement. Materials and Methods The maxillary arch was divided into four anatomically defined regions for measurements of bone quantity. Bone quality was assessed histologically and described by trabecular bone patterns and tissue composition. Results Average bone height with a minimum thickness of 4 mm was as follows: region 1, 12.1 ± 4.9 mm; region 2, 14.1 ± 7.2 mm; region 3, 6.1 ± 2.8 mm; and region 4, 8.5 ± 2.2 mm. Histological evaluation showed increased trabeculation and thicker cortex in the maxillary anterior area, regions 1 and 2. Region 3, the floor of the maxillary sinus area, had the least amount of bone; however, the quality of bone was superior to that of region 4, the maxillary tuberosity area. Trabecular distance or marrow spaces ranged from 40 μm to 2 mm with larger spaces associated with the posterior maxilla. Conclusions Maxillary tuberosity is the least desirable site for the placement of implants in the maxilla. The area corresponding to the first and second molars had the least bone thickness. All measures of bone preservation need to be considered, especially in this area.     

Bone block allograft impregnated with bone marrow aspirate

PURPOSE: To evaluate the influence of bone marrow aspirate when added to bone block allograft to repair osseous defects. BACKGROUND: Bone-marrow aspirate has been combined with xenograft and allograft particulate material and has produced a significant quantity of new bone growth. However, the use of allograft bone blocks has advantages in some clinical situations. This article discusses cell-based therapies by means of in vivo transplantation of stem cells derived from bone-marrow aspirate and incorporated into allograft corticocancellous bone block for bone regeneration. MATERIALS: A technique for combining bone-marrow aspirate with block allografts was developed. To evaluate its influence in repairing osseous defects, a maximum of 3 to 4 mL of bone marrow was aspirated from the anterior iliac crest of 5 patients who had severely atrophic maxillary and mandibular ridges. Five sites were grafted with allograft bone blocks saturated with bone-marrow aspirate and secured with bone screws (ACE Surgical Supply Company, Inc. Brockton, MA). At one of the sites a core specimen was taken 4 months after implant placement and submitted for standard histologic and histomorphometric analysis. RESULTS: After 4 to 8 months of healing, all the grafts had integrated into the recipient bone. Implants were placed at all 5 sites and osseointegrated successfully. Examination of the bone core showed the graft to be well-integrated, with 54% of the core consisting of bone and 46% of marrow. Eighty-nine percent of the bone was vital. CONCLUSION: Impregnation of bone-marrow aspirate into allograft bone block activates the body's ability to form new bone. The bone-marrow aspiration technique is less invasive than harvesting autogenous bone from a second surgical site, offers predictable results, and is cost effective.     

Histologic evaluation of autogenous calvarial bone in maxillary onlay bone grafts: a report of 2 cases

Bone augmentation for implant dentistry has become a necessary procedure for a number of edentulous patients. Calvarial bone grafting constitutes an important tool in achieving maxillary augmentation and sinus elevation. Much effort has been directed toward improving graft survival and volumetric maintenance. The purpose of the present study was to evaluate the histologic results of the calvarial onlay graft for maxillary reconstruction before implant placement. Two patients underwent maxillary augmentation using autogenous calvarial onlay grafts. After a 4-month healing period, biopsies of the augmented regions were performed and implants were placed. The implants were loaded after 5 months and then clinically examined after 15 months of function. Biopsies showed that calvarial onlay grafts were well incorporated into the preexisting bone after a 4-month period. Histologic and histomorphometric findings demonstrated a living bone that showed features characteristic of mature and compact osseous tissue. The restored Implants were stable and osseointegrated after a 15-month period of follow-up. The use of calvarial onlay grafts can be a predictable and successful method to achieve maxillary augmentation, allowing appropriate placement of implants and stable prosthetic restorations.     

Maxillary sinus augmentation with the xenograft Bio-Oss and autogenous intraoral bone for qualitative improvement of the implant site: a histologic and histomorphometric clinical study in humans

The aim of the present clinical study was to determine, through histologic and histomorphometric investigations of human bone specimens, whether the addition of autogenous bone to the bone substitute material Bio-Oss can produce a high-quality implant site. To improve vertical bone height, 13 sinus floor elevations were carried out in a total of 12 patients. Augmentation of the maxillary sinus floor was completed using a mixture of Bio-Oss and bone harvested intraorally from the mandibular symphysis, the retromolar space, or the tuberosity region. Following an average of 7.1 months of healing, 36 Br?nemark System implants were placed. During this surgical intervention, 23 cylinder-shaped bone biopsies were taken from the augmented maxillary region using trephine burs. Histologic analysis of the bone biopsies revealed that the Bio-Oss granulate was well-integrated into the newly formed bone; 33.1% (+/- 12.4%) of the substitute material surface was in direct contact with bone. Histomorphometric analysis of the samples revealed an average percentage proportion of bone of 18.9% (+/- 6.4%). The bovine substitute material and soft tissue occupied, respectively, 29.6% (+/- 8.9%) and 51.5% (+/- 9.4%) of the measured surface. When the implants were uncovered after an average healing phase of 6 months, all 36 implants had become osseointegrated. The combination of osteoconductive Bio-Oss and osteoinductive autogenous bone thus proved to be a material suitable for application in sinus floor augmentation.     

Histomorphometric Analysis of Human Maxillary Sinus Lift with a New Bone Substitute Biocomposite: A Preliminary Report

Purpose: To analyze radiographic and histological outcomes of maxillary sinus floor augmentation using a calcium-sulfate based allograft containing demineralized bone matrix particles.
Materials and Methods: Fifteen maxillary sinus lift procedures with simultaneous placement of titanium implants were performed in 12 patients of both genders aged 36–71 years. Each sinus cavity was filled by the biocomposite. After 3 months of healing, all surgical sites were uncovered and bone biopsies were retrieved for undecalcified histology and histomorphometry. The ratio between the original and the grafted sinus height (GSH/OSH) was computed using a panoramic radiography taken immediately after surgery and at 3 months of healing, and the two ratios were compared by Wilcoxon signed-rank test.
Results: By 3 months, all implants were stable without clinical and radiographic signs of infection. Significant changes in GSH/OSH during healing were seen (2.7 ± 0.6 initially vs. 2.6 ± 0.5 after healing; p  = 0.01). Histologic findings showed newly formed bone surrounding the residual grafted particles without inflammation. At 3 months, mean regenerated bone density was 33.8 ± 8.6%; marrow spaces amounted to 32.3 ± 10.3%; residual graft was 33.9 ± 9.0%. Similar histomorphometric and radiographic results were obtained independently from patient age or sex.
Conclusions: The analysed putty seems to be a safe and effective graft material for maxillary sinus floor augmentation by accelerating bone regeneration and thus reducing the healing time.     

上颌后牙区无牙位点在锥形束CT中的解剖学表现

目的 基于锥形束CT（CBCT）分析上颌后牙区无牙位点的相关骨解剖特点。方法 本项研究共选取了上颌后牙区至少有一个缺牙的100名患者的CBCT图像资料,共217个无牙位点。测量无牙位点的剩余牙槽嵴高度、剩余牙槽嵴宽度和角度A,并分析上颌窦底的形态特点。结果 平均剩余牙槽嵴高度为9.53 mm,其中小于10 mm者占62.67%（136/217）。平均剩余牙槽嵴宽度为9.30 mm,大于6 mm占91.71%（199/217）。磨牙区剩余牙槽嵴高度小于前磨牙区,剩余牙槽嵴宽度呈相反趋势。上颌窦底形态以倾斜型（64.52%）为主。角度A小于30°、30°~60°和大于60°者分别占10.14%、42.40%和47.47%。结论 上颌后牙区缺牙位点进行种植手术前,多数需行上颌窦底提升手术增加骨量,建议根据CBCT检查结果评价上颌窦解剖结构从而制定合理的种植方案。     

原位取骨技术在上前牙种植中的应用

上前牙种植手术中常于下颌颏部、下颌升支等处获取自体骨行骨增量,但多篇文献报道了供骨术区的并发症。于上前牙邻近区域及缺牙区原位取骨,可减少手术时间、供区并发症,增加患者对取骨手术的接受度。该文就上前牙区潜在取骨区域及取骨方式进行简单论述,为不同大小的上前牙区骨缺损原位取骨手术方案的选择提供参考和借鉴。     

A histomorphogenic analysis of bone grafts augmented with adult stem cells

PURPOSE: To evaluate the influence of bone marrow aspirate added to xenograft or alloplast graft matrix scaffold to produce bone. MATERIALS: A maximum of 4 cc bone marrow was aspirated from the anterior iliac crest of 5 patients to saturate the matrix scaffold prior to bone graft. Seven graft sites evaluated included sinus lift augmentation, particulate onlay graft of the maxilla via a tunneling procedure, and particulate onlay graft of the maxilla stabilized with titanium mesh. The xenograft scaffold was either PepGen Putty (DENTSPLY Friadent CeraMed, Lakewood, CO) or C-Graft resorbable algae material (Clinician's Preference, Golden, CO). The alloplast scaffold was beta-tricalcium phosphate (either Curasan AG, Kleinostheim, Germany, or Vitoss; Malvern, PA). RESULTS: Graft sites healed for 4-7 months. Core specimens of graft sites were taken with trephine drills, and submitted for standard histologic and histomorphogenic analysis. The percentage of graft material converted into bone, percentage of vital graft matrix, percentage of unresorbed matrix, and percentage of remaining interstitial tissue were measured. After a 4-month healing of sinus-lift augmentation with C-Graft, the biopsy showed 31% bone that was 100% vital. Unresorbed graft material was 26%, and remaining interstitial material constituted 43%. Using pure phase beta-tricalcium phosphate, a 4-month core biopsy showed 40% bone that was 100% vital. Residual graft was 3% and interstitial material 57%. A sinus grafted with PepGen P-15 (DENTSPLY Friadent CeraMed) was found to be 14% bone, with 100% of that bone vital. The non-bone within the core was 36%. After a 4 1/2-month healing of bilateral sinus grafts using a nonpure phase beta-tricalcium phosphate, the percentage of the biopsy that was bone was 23% on the right side and 16% on the left side. Vital bone was 89% (right side) and 86% (left side). The core taken after 4 months of healing from the anterior maxilla particulate onlay graft with PepGen P-15 showed 32% bone, with 100% found to be vital. Non-bone within the core was 15%, and 53% was interstitial material. After 7 months of healing, a biopsy core from the maxillary ridge augmented with C-Graft was 45% newly formed bone, with 100% of the bone vital. There was no residual graft material present. DISCUSSION: Bone regeneration by cell-based strategies depends upon an understanding of the biology and potential of adult stem cells as a method of regenerating bone. CONCLUSIONS: Bone marrow aspirate containing adult stem cells when mixed with bioengineered graft materials provide a scaffold to support the proliferation, differentiation, and maturation of the stem cells, as well as facilitating angiogenesis. This article presents histological evidence that stem cells aspirated from bone marrow and transplanted onto biocompatible scaffolds can successfully regenerate bone. This new standard for bone grafting may emerge as an alternative to autogenous bone grafts.     

Histomorphometrical analysis of bone formed after maxillary sinus floor augmentation by grafting with a combination of autogenous bone and demineralized freeze-dried bone allograft or hydroxyapatite

BACKGROUND: Maxillary sinus floor augmentation procedures are currently the treatment of choice when the alveolar crest of the posterior maxilla is insufficient for dental implant anchorage. This procedure aims to obtain enough bone with biomaterial association with the autogenous bone graft to create volume and allow osteoconduction. The objective of this study was to histologically and histometrically evaluate the bone formed after maxillary sinus floor augmentation by grafting with a combination of autogenous bone, from the symphyseal area mixed with DFDBA or hydroxyapatite. METHODS: Ten biopsies were taken from 10 patients 10 months after sinus floor augmentation using a combination of 50% autogenous bone plus 50% demineralized freeze-dried bone allograft (DFDBA group) or 50% autogenous bone plus 50% hydroxyapatite (HA group). Routine histological processing and staining with hematoxylin and eosin and Masson's trichrome were performed. RESULTS: The histomorphometrical analysis indicated good regenerative results in both groups for the bone tissue mean in the grafted area (50.46+/-16.29% for the DFDBA group and 46.79+/-8.56% for the HA group). Histological evaluation revealed the presence of mature bone with compact and cancellous areas in both groups. The inflammatory infiltrate was on average nonsignificant and of mononuclear prevalence. Some biopsies showed blocks of the biomaterial in the medullary spaces close to the bone wall, with absence of osteogenic activity. CONCLUSIONS: The results indicated that both DFDBA and HA associated with an autogenous bone graft were biocompatible and promoted osteoconduction, acting as a matrix for bone formation. However, both materials were still present after 10 months.     

Evaluation of sinus floor elevation using a composite bone graft mixture

BACKGROUND: The performance of implant surgery in the posterior maxilla often poses a challenge due to insufficient available bone. Sinus floor elevation was developed to increase needed vertical height to overcome this problem. The present study described and reported a simple, safe and predictable bone graft mixture for the sinus lifting procedure. MATERIAL AND METHODS: Seventy patients were recruited for this study and underwent a sinus lift procedure. All sites were treated with a composite graft of cortical autogenous bone, bovine bone and platelet-rich plasma (PRP). A total of 263 implants (171 Astra Tech and 92 Microdent) were placed either simultaneously or delayed. All sites were clinically and radiographically evaluated 24 months after their prosthetic loading. Biopsy samples were taken from 16 delayed implant placement sites at the time of their implant placement. RESULTS: A 100% implant success rate was found after 24 months of functioning. Only two Microdent implants failed before loading, which translates to a 99% overall implant success rate. No statistically significant differences were found between simultaneous and delayed implant placement. Image processing revealed 34+/-6.34% vital bone, 49.6+/-6.04% connective tissue and 16.4+/-3.23% remaining Bio-Oss particles. However, the histomorphometric analysis showed that the bovine bone was incorporated into new bone formation. CONCLUSION: The results showed that a composite graft comprised of cortical autogenous bone, bovine bone and PRP mixture can be successfully used for sinus augmentation.     

Quantitative and qualitative comparison of the maxillary bone regeneration after beta-tricalcium phosphate and autogenous bone implantation

Graft insertion can effectively enhance the regeneration of debilitated bone. The effects of an alloplastic bone-replacing material, beta-tricalcium phosphate (Cerasorb), and of autogenous bone graft were compared. In 17 edentulous patients, the maxillary sinus floor was extremely atrophied to such an extent that implant placement was impossible. The Schneiderian membrane was surgically elevated bilaterally by insertion of Cerasorb (experimental side) and autogenous bone graft (control side). After surgery, the recovery was followed clinically and radiologically. After 6 months, 68 bone cylinders were excised from the grafted areas and implants were inserted into their places. The bone samples were embedded into resin, and the osteointegration of the grafts was studied histologically. Trabecular bone volume (TBV) and trabecular bone pattern factor (TBPf) were quantified by histomorphometry. Cerasorb proved to be an effective bone-replacing material with osteoconductivity; it was capable of gradual disintegration, thereby providing space for the regenerating bone. The new bone density was not significantly different on the experimental and control sides (32.4 +/- 10.9% and 34.7 +/- 11.9%, respectively). However, the graft biodegradation was significantly slower on the experimental side than on the control side. The TBPf value was lower on the control side than on the experimental side (-0.53 +/- 1.7 mm(-1) and -0.11 +/- 1.4 mm(-1), respectively); but this difference was not significant. Six months after insertion of the grafts, the bone of the augmented sinus floor was strong and suitable for anchorage of dental implants, irrespective of whether autogenous bone or Cerasorb particles had been applied.     

Maxillary sinus floor grafting with beta-tricalcium phosphate in humans: density and microarchitecture of the newly formed bone

OBJECTIVES: Graft insertion can effectively enhance the regeneration of debilitated bone. The effects of an alloplastic bone-replacing material, beta-tricalcium phosphate (Cerasorb), and of autogenous bone graft were compared. MATERIALS AND METHODS: In 17 edentulous patients, the maxillary sinus floor was extremely atrophied to such an extent that implant placement was impossible. The Schneiderian membrane was surgically elevated bilaterally by insertion of Cerasorb (experimental side) and autogenous bone graft (control side). After surgery, the recovery was followed clinically and radiologically. After 6 months, 68 bone cylinders were excised from the grafted areas and implants were inserted into their places. The bone samples were embedded into resin, and the osteointegration of the grafts was studied histologically. Trabecular bone volume (TBV) and trabecular bone pattern factor (TBPf) were quantified by histomorphometry. RESULTS: Cerasorb proved to be an effective bone-replacing material with osteoconductivity; it was capable of gradual disintegration, thereby providing space for the regenerating bone. The new bone density was not significantly different on the experimental and control sides (32.4+/-10.9% and 34.7+/-11.9%, respectively). However, the graft biodegradation was significantly slower on the experimental side than the control side. The TBPf value was lower on the control side than on the experimental side (-0.53+/-1.7 and -0.11+/-1.4 mm(-1), respectively), but this difference was not significant. CONCLUSIONS: Six months after insertion of the grafts, the bone of the augmented sinus floor was strong and suitable for anchorage of dental implants, irrespective of whether autogenous bone or Cerasorb particles had been applied.     

Maxillary sinus augmentation with a synthetic cell-binding peptide: histological and histomorphometrical results in humans

Bone substitutes should be used when sufficient amounts of autologous bone cannot be harvested from intraoral donor sites. P-15 is a highly conserved linear peptide with a 15 amino acid sequence identical to the sequence contained in the residues 766 to 780 of the alpha-chain of type I collagen. PepGen P-15 (Dentsply Friadent, Mannheim, Germany) is a combination of the mineral component of bovine bone (Osteograf/N 300) with P-15. Bio-Oss (Geistlich, Mannheim, Germany) is a deproteinized sterilized bovine bone with 75% to 80% porosity and a crystal size of approximately 10 microm in the form of cortical granules. The purpose of the present histological and histomorphometrical study was to compare maxillary sinus augmentation procedures in humans performed with PepGen P-15 with procedures associated with Bio-Oss and autologous bone. Seven patients participated in this study (3 men and 4 women; ages between 48 and 69 years, mean of 58 years) and were categorized into 3 groups. In group 1, a mixture of 50% autologous bone from an intraoral source and 50% Bio-Oss was used. In group 2, the graft materials used were 50% Bio-Oss and 50% PepGen P-15. In group 3, 50% autologous bone and 50% PepGen P-15 were used. Group 1 histomorphometry showed that the percentage of newly formed bone was 38.7% +/- 3.2%, marrow spaces represented 45.6% +/- 5%, and residual graft particles constituted the remaining 14.4% +/- 2.1%. Group 2 histomorphometry showed that newly formed bone represented 36.7% +/- 3.3%, marrow spaces represented 39.7% +/- 3.4%, and residual graft particles represented 19.6% +/- 2.1%. In group 3, newly formed bone represented 32.2% +/- 3.2%, marrow spaces represented 38% +/- 2.5%, and residual graft particles represented 28.8% +/- 1.1%. Non-statistically significant differences were found in the percentage of newly formed bone in the different groups (P = .360). Statistically significant differences were found in the percentage of residual graft materials among the different groups (group 1 vs groups 2 and 3) (P = .0001). These data demonstrate that the use of bone-replacement materials, without the addition of autologous bone, could be an alternative in sinus augmentation procedures. Such treatment would increase patient satisfaction, decrease surgical complications, and save the clinician substantial operating time.