Does platelet-rich plasma promote remodeling of autologous bone grafts used for augmentation of the maxillary sinus floor? Prospective randomized, controlled trial of sinus grafting using Escherichia-coli-produced rhBMP-2 with a biphasic calcium phosphate carrier compared to deproteinized bovine bone. Maxillary Sinus Grafting With Biphasic Bone Ceramic or Autogenous Bone: Clinical, Histologic, and Histomorphometric Results From a Randomized Controlled Clinical Trial Histomorphometric and immunohistochemical assessment of RUNX2 and VEGF of Biogran™ and autogenous bone graft in human maxillary sinus bone augmentation: A prospective and randomized study Effects of directly autotransplanted tibial bone marrow aspirates on bone regeneration and osseointegration of dental implants. Histomorphometric comparison of a biphasic bone ceramic to anorganic bovine bone for sinus augmentation: 6- to 8-month postsurgical assessment of vital bone formation. A pilot study. Maxillary Sinus Augmentation Combining Bio-Oss with the Bone Marrow Aspirate Concentrate: A Histomorphometric Study in Humans Maxillary sinus floor elevation with bovine bone mineral combined with either autogenous bone or autogenous stem cells: a prospective randomized clinical trial. Platelet-rich plasma activity on maxillary sinus floor augmentation by autologous bone. Efficacy of rhBMP-2/Hydroxyapatite on Sinus Floor Augmentation The influence of bone substitute materials on the bone volume after maxillary sinus augmentation: a microcomputerized tomography study Comparison between mineralized cancellous bone allograft and an alloplast material for sinus augmentation: A split mouth histomorphometric study Bone formation with a biphasic calcium phosphate combined with fibrin sealant in maxillary sinus floor elevation for delayed dental implant. Bioactive glass granules as a bone adjunctive material in maxillary sinus floor augmentation. Anorganic bovine-derived hydroxyapatite vs β-tricalcium phosphate in sinus augmentation: a comparative histomorphometric study. A 3-year clinical follow-up of implants placed in two different biomaterials used for sinus augmentation. Effect of platelet-rich plasma on sinus lifting: a randomized-controlled clinical trial. Histologic findings in sinus augmentation with autogenous bone chips versus a bovine bone substitute. Bone marrow concentrate and bovine bone mineral for sinus floor augmentation: a controlled, randomized, single-blinded clinical and histological trial--per-protocol analysis. Scintigraphic, histologic, and histomorphometric analyses of bovine bone mineral and autogenous bone mixture in sinus floor augmentation: a randomized controlled trial--results after 4 months of healing. Short dental implants as compared to maxillary sinus augmentation procedure for the rehabilitation of edentulous posterior maxilla: Three‐year results of a randomized clinical study Effect of Porous Titanium Granules on Bone Regeneration and Primary Stability in Maxillary Sinus: A Human Clinical, Histomorphometric, and Microcomputed Tomography Analyses Maxillary sinus augmentation: histologic and histomorphometric analysis. Maxillary sinus grafting with Bio-Oss or Straumann Bone Ceramic: histomorphometric results from a randomized controlled multicenter clinical trial. Histomorphometric comparison of different concentrations of recombinant human bone morphogenetic protein with allogeneic bone compared to the use of 100% mineralized cancellous bone allograft in maxillary sinus grafting. Maxillary sinus grafting with autograft vs. fresh frozen allograft: a split-mouth histomorphometric study. Platelet-Rich Plasma and Deproteinized Bovine Bone Matrix in Maxillary Sinus Lift Surgery: A Split-Mouth Histomorphometric Evaluation Histomorphometric Evaluation of Two Different Bone Substitutes in Sinus Augmentation Procedures: A Randomized Controlled Trial in Humans. Platelet-Rich Plasma in Grafted Maxillae: Growth Factor Quantification and Dynamic Histomorphometric Evaluation Histologic and histomorphometric assessment of sinus‐floor augmentation with beta‐tricalcium phosphate alone or in combination with pure‐platelet‐rich plasma or platelet‐rich fibrin: A randomized clinical trial A prospective multicenter randomized clinical trial of autogenous bone versus beta-tricalcium phosphate graft alone for bilateral sinus elevation: histologic and histomorphometric evaluation. Topical use of platelet-rich plasma to influence bone volume in maxillary augmentation: a prospective randomized trial. Exploring the Geometry of Treatment Networks Maxillary sinus augmentation with leukocyte and platelet‐rich fibrin and deproteinized bovine bone mineral: A split‐mouth histological and histomorphometric study Evaluation of hyaluronic matrix efficacy in sinus augmentation: a randomized-controlled histomorphometric and micro-computed tomography analysis. Histological evaluation of maxillary sinus floor augmentation with recombinant human growth and differentiation factor-5-coated β-tricalcium phosphate: results of a multicenter randomized clinical trial.
The aim of this study was to evaluate the effect of platelet-rich plasma ( PRP ) on remodeling of autologous bone grafts used for augmentation of the floor of the maxillary sinus . In five edentulous patients suffering from insufficient retention of their upper denture related to a severely resorbed maxilla , the floor of both maxillary sinus was augmented with an autologous bone graft from the iliac crest . R and omly , PRP was added to the bone graft used to augment the floor of the left or right sinus ( split-mouth design ) . Three months after the reconstruction , bone biopsies were taken with a trephine from the planned implant sites ( N=30 ) . Subsequently , three implants were placed in the left and right posterior maxilla . Microradiograms were made of all biopsies ( N=30 ) , whereafter the biopsies were processed for light microscopic examination . In addition , clinical parameters were scored . Wound healing was uneventful , clinical ly no difference was observed between the side treated with PRP or not . Also microradiographical and histomorphological examination of the biopsies revealed no statistical difference between the PRP- and non-PRP side . One implant placed in the PRP side of the graft was lost during the healing phase . Implant-retained overdentures were fabricated 6 months after implantation . All patients functioned well ( follow-up 20.2+/-4.3 months ) . In this study , no beneficial effect of PRP on wound healing and bone remodeling was observed . It is posed that PRP has no additional value in promoting healing of grafted non-critical size defects AIM This study compared the effects of Escherichia-coli-produced recombinant human bone morphogenetic protein 2 ( ErhBMP-2 ) with a biphasic calcium phosphate ( BCP ) carrier to those of deproteinized bovine bone in human maxillary sinus floor augmentation . MATERIAL AND METHODS Screening for this clinical trial selected 56 sites that provided informed consent to participate , of which 46 were ultimately enrolled and 41 were finally included in the study . The sites were divided into two groups using a r and om-number table , and the material was applied . A trephine biopsy was performed after 24 weeks , and implants wider than the biopsy site were inserted . Computed tomography and plain panoramic images were obtained immediately and then again at 24 weeks after the surgery . Radiographic images were reconstructed to allow measurement of the linear and volumetric changes . The biopsy sample s were processed for histologic and histometric analyzes . RESULTS All sites healed uneventfully with no complications . Radiographic analysis revealed a tendency for the volume to increase , but the difference was not statistically significant in either group . Comparison of volumetric changes between the two groups also revealed no significant difference . Moreover , none of the histometric parameters differed significantly between the groups , although different healing patterns were observed on histologic analysis . CONCLUSIONS AND CLINICAL IMPLICATION S It can be concluded that sinus augmentation with ErhBMP-2 carrying BCP carrier did not enhance bone regeneration compared to the conventional treatment using deproteinized bovine bone at 24 weeks after the surgery Purpose : The present , r and omized , controlled clinical trial compared the histologic and histomorphometric results from maxillary sinus augmentation with either biphasic calcium phosphate ( BCP ) ( 60 % hydroxyapatite and 40 % & bgr;-tricalcium phosphate ) or autogenous bone ( AB ) as bone-grafting material s. Material and Methods : Ten patients received bilateral sinus elevation surgery with intraoral AB chips ( control group ) on one side and BCP ( test group ) on the contralateral side . After a healing period of 6 to 8 months , implant sites were created and trephine cores were harvested for histological and histomorphometric analysis of the grafted areas . Results : The histological examination of biopsies showed BCP particles interconnected by bridges of a vital newly formed bone . Histomorphometry demonstrated that the amount of newly formed bone in the control group ( 36.8 % ) was significantly greater than that in the BCP ( 28.2 % ) group ( P = 0.0032 ) . BCP and AB cores revealed an average of residual graft particles of 32.9 % and 4.8 % , respectively . The average percentage of soft tissue components was 38.9 % in the BCP cores and 58.4 % in the AB cores . Conclusions : Based on our findings , the amount of vital bone formation was significantly higher for AB than that for BCP . However , BCP seemed to be a biocompatible and osteoconductive material that can be used with success as a bone substitute in maxillary sinus procedures BACKGROUND Few studies have been conducted to assess new bone formation using Biogran , a bioactive glass , in maxillary sinus bone augmentation through a prospect i ve and r and omized evaluation . Moreover , there are no studies that evaluate cellular behavior by immunohistochemical assessment for osteoblastic and vascular activity during bone repair . PURPOSE The aim of this study is to compare new bone formation and cellular behavior with Biogran alone , a 1:1 combination of Biogran and autogenous bone graft , and autogenous bone graft alone in human maxillary sinuses . MATERIAL S AND METHODS Ten maxillary sinuses were grafted with Biogran ( Group 1 ) ,  10 grafted with Biogran added to autogenous bone graft in a 1:1 ratio ( Group 2 ) , and 10 grafted with autogenous bone graft alone ( Group 3 ) . After 6 months of bone healing , sample s were obtained concurrent to the dental implants ' placement to be evaluated by histomorphometric and immunohistochemical assessment for RUNX2 and vascular endothelial growth factor ( VEGF ) . RESULTS The amount of new bone formation in Group 1 was 42.0 ± 7.3 % in the pristine bone region , 40.7 ± 14.0 % in the intermediate region , and 45.6 ± 13.5 % in apical region . In Group 2 , for pristine bone , intermediate , and apical regions , new bone formation was 36.6 ± 12.9 % , 33.2 ± 13.3 % , and 45.8 ± 13.9 % , respectively . Group 3 showed new bone formation of 37.3 ± 11.6 % , 35.3 ± 14.7 % , and 39.9 ± 15.8 % in pristine bone , intermediate , and apical regions , respectively . The immunolabeling for RUNX2 showed low cellular activity in osteoblasts for all groups , and the VEGF assessment demonstrated moderate cellular activity in Groups 1 and 2 ; however , Group 3 presented with low activity in the pristine bone region , followed by moderate activity in the intermediate and apical region . CONCLUSION This study demonstrates that Biogran and its combination with autogenous bone graft 1:1 are good bone substitutes due to their similarity to autogenous bone graft OBJECTIVES Aim of the pilot trial was to evaluate applicability and effects of directly autotransplanted tibial bone marrow ( BM ) aspirates on the incorporation of porous bovine bone mineral in a sinus lift model and on the osseointegration of dental implants . MATERIAL AND METHODS Six edentulous patients with bilaterally severely resorbed maxillae requiring sinus augmentation and implant treatment were included . During surgery , tibial BM was harvested and added to bone substitute material ( Bio-Oss ( ® ) ) at the r and omly selected test site . At control sites , augmentation was performed with Bio-Oss ( ® ) alone . The cellular content of each BM aspirate was checked for multipotency and surface antigen expression as quality control . Histomorphometric analysis of biopsies from the augmented sites after 3 and 6 months ( during implantation ) was used to evaluate effects on bone regeneration . Osseointegration of implants was evaluated with Periotest ( ® ) and radiographic means . RESULTS Multipotent cellular content in tibial BM aspirates was comparable to that in punctures from the iliac crest . No significant difference in amount of new bone formation and the integration of bone substitute particles was detected histomorphometrically . Periotest ( ® ) values and radiographs showed successful osseointegration of inserted implants at all sites . CONCLUSION Directly autotransplanted tibial BM aspirates did not show beneficial regenerative effects in the small study population ( N = 6 ) of the present pilot trial . However , the proximal tibia proved to be a potential donor site for small quantities of BM . Future trials should clarify whether concentration of tibial BM aspirates could effect higher regenerative potency This blinded , r and omized , controlled pilot investigation is the first to histomorphometrically compare vital bone formation following bilateral sinus grafting with a biphasic calcium phosphate ( BCP ) ( Straumann Bone Ceramic ) to an anorganic bovine bone matrix ( ABBM ) ( Bio-Oss ) 6 to 8 months following graft placement . Twelve patients were selected . Following elevation of the lateral sinus walls , one material was placed in the right sinus and the other material was placed in the left sinus , as determined by r and omization . Six to 8 months after grafting ( with the same time frame used for each patient ) , a trephine core was taken from the grafted area and sent for histomorphometric analysis . Cores were obtained from 21 healed sinuses in 12 patients . Nine patients provided bilateral cores . Histomorphometric analysis of 10 BCP cores and 11 ABBM cores revealed an average vital bone content of 28.35 % and 22.27 % , respectively . The average percentage of residual graft particles was 28.4 % in the BCP cores and 26.0 % in the ABBM cores . The difference in vital bone formation was not significantly different ( n = 9 patients , paired t test ) between bilateral sinuses treated with the BCP and those treated with the ABBM . Histologically , both material s appeared to be osteoconductive and support new bone formation . Future studies are needed to confirm the ability of this regenerated bone to support dental implant maintenance over time Purpose . To investigate the regenerative results obtained with the association of bone marrow aspirate concentrate using the Bone Marrow Aspirate Concentrate ( BMAC ) method to a xenogeneic bone graft ( Bio-Oss ) in sinus floor elevation . Material s and Methods . Using a r and omized controlled study design in eight consecutive patients ( age of 55.4 ± 9.2 years ) , 16 sinus floor lift procedures were performed with Bio-Oss alone ( control group , CG , n = 8) or combined with bone marrow aspirate concentrate obtained via the BMAC method ( test group , TG , n = 8) . Six months after the grafting procedures , bone biopsies were harvested during implant placement and were analyzed by histomorphometry . Results . Histomorphometric analysis revealed a significantly higher amount ( p < 0.05 ) of vital mineralized tissue in TG when compared to the CG ( 55.15 ± 20.91 % and 27.30 ± 5.55 % , resp . ) . For nonvital mineralized tissue , TG presented a statistically higher level of Bio-Oss resorption ( p < 0.05 ) when compared with the CG ( 6.32 ± 12.03 % and 22.79 ± 9.60 % , resp . ) . Both groups ( TG and CG ) showed no significantly different levels ( p > 0.05 ) of nonmineralized tissue ( 38.53 ± 13.08 % and 49.90 ± 7.64 % , resp . ) . Conclusion . The use of bone marrow concentrate obtained by BMAC method increased bone formation in sinus lift procedures AIM To assess whether differences occur in bone formation after maxillary sinus floor elevation surgery with bovine bone mineral ( BioOss ( ® ) ) mixed with autogenous bone or autogenous stem cells . The primary endpoint was the percentage of new bone three months after the elevation procedure . MATERIAL AND METHODS In a r and omized , controlled split-mouth design , in 12 consecutive patients ( age 60.8 ± 5.9 years , range 48 - 69 years ) needing reconstruction of their atrophic maxilla , a bilateral sinus floor augmentation procedure was performed . R and omly , on one side the augmentation procedure was performed with bovine bone mineral ( BioOss ( ® ) ) seeded with mononuclear stem cells harvested from the posterior iliac crest ( test group ) while BioOss ( ® ) mixed with autogenous bone ( harvested from the retromolar area ) was applied on the contra-lateral side ( control group ) . On 14.8 ± 0.7 weeks after the sinus floor elevation , biopsies from the reconstructed areas were taken at the spots where subsequently the endosseous implants were placed . The biopsies were histomorphometrically analyzed . RESULTS Significantly more bone formation was observed in the test group ( 17.7 ± 7.3 % ) when compared with the control group ( 12.0%± 6.6 ; P=0.026 ) . In both the test and control group , all implants could be placed with primary stability . In one patient , not all biopsies contained BioOss ( ® ) . This patient was excluded from analysis . CONCLUSION Mesenchymal stem cells seeded on BioOss ( ® ) particles can induce the formation of a sufficient volume of new bone to enable the reliable placement of implants within a time frame comparable with that of applying either solely autogenous bone or a mixture of autogenous bone and BioOss ( ® ) . This technique could be an alternative to using autografts OBJECTIVES This work aims to evaluate the regenerative potential of platelet-rich plasma ( PRP ) on an implant site of peculiar clinical impact , such as sinus augmentation . MATERIAL AND METHODS Sixteen consenting patients ( 11 females and five males ) , with symmetrical maxillary sinus atrophy , underwent bilateral sinus floor augmentation  , using autologous ( iliac crest ) bone on one side and PRP plus autologous bone contralaterally . Implants were inserted 4 , 5 , 6 and 7 months after surgery in the patients r and omly split into four groups .  Orthopantomographies , computed tomography with transverse image digital reconstructions and densitometries  were used to monitor the treatment progress . A core biopsy was performed at the site of implant . RESULTS Clinical performance across both sites showed no statistical significance ( P=0.414 ) . Densitometric values were higher at PRP sites ( mean Hounsfield units approximately + 57 % ) , even if densitometry converged in the two sites 8 months after surgery . Histology documents enhanced bone activities in sites treated with PRP , 4 months after surgery . Reduced bone activity was observed in both sites 5 , 6 and 7 months after surgery . Bone amount , higher in sites treated with PRP ( mean trabecular bone volume approximately + 37 % ) , decreased in both sites over time . CONCLUSIONS Our results seem to indicate a certain regenerative potential of PRP when used with autologous bone . The effect of this enhancement of bone regeneration appeared to be restricted to shorter treatment times . A progressive extinguishment of the PRP effect is recorded after an interval longer than 6 - 7 months The aim of this r and omized single-blinded active-controlled clinical study was to evaluate the early efficacy of low-dose Escherichia coli – derived recombinant human bone morphogenetic protein 2 ( rhBMP-2 ) soaked with hydroxyapatite granules ( BMP-2/H ) as compared with an inorganic bovine bone xenograft ( ABX ) in maxillary sinus floor augmentation . In a total of 127 subjects who were enrolled at 6 centers , maxillary sinus floors were augmented with 1 mg/mL of rhBMP-2 ( 0.5 to 2.0 mg per sinus ) and BMP-2/H ( 0.5 to 2.0 g ; n = 65 ) or with ABX alone ( 0.5 to 2.0 g ; n = 62 ) . Core biopsies were obtained 3 mo after the augmentation surgery and were analyzed histomorphometrically . The mean new bone formation with BMP-2/H and ABX augmentation was 16.10 % ± 10.52 % and 8.25 % ± 9.47 % , respectively . The BMP-2/H group was noninferior to the ABX group ; the lower limit of the 1-sided 97.5 % confidence interval for the difference between the 2 groups was calculated as 4.33 % , which was greater than the prespecified noninferiority margin of −3.75 % . An additional test with the Wilcoxon rank-sum test with a 2-sided 5 % significance level showed that bone formation between the 2 groups was significantly different ( P < 0.0001 ) . The soft tissue and residual graft areas showed no significant differences between the groups . With regard to safety , no significant difference between the 2 groups was observed ; there was no significant increase in the amount of rhBMP-2 antibody in the serum after BMP-2/H grafting . Our study suggested that low-dose Escherichia coli – derived rhBMP-2 with hydroxyapatite was effective in early stages for enhanced bone formation after maxillary sinus floor augmentation without harmful adverse events ( Clinical trials.gov NCT01634308 ) Objectives This study aims to evaluate the effect of adding bone substitute material s ( BSM ) to particulated autogenous bone ( PAB ) on the volume fraction ( Vf ) of newly formed bone after maxillary sinus augmentation . Material s and methods Thirty healthy patients undergoing maxillary sinus augmentation were included .  PAB ( N = 10 ) , mixtures of PAB and beta-tricalciumphosphate ( PAB/β-TCP ) ( N = 10 ) , as well as PAB and β-TCP and hydroxyapatite ( PAB/HA/β-TCP ) ( N = 10 ) were r and omly used for sinus augmentation . A sample of the graft material was maintained from each patient at time of maxillary sinus augmentation , and Vfs of the PAB and /or BSM in the sample s were determined by means of microcomputerized tomography ( μ-CT ) . Five months later , sample s of the grafted areas were harvested during implantation using a trephine bur . μ-CT analysis of these sample s was performed , and the Vf of bone and BSM were compared with the data obtained 5 months earlier from the original material . Results The mean Vf of the bone showed a statistically significant increase ( p < 0.05 ) in all groups after a healing period of 5 months without statistically significant difference between the groups . Conclusions With regard to the increase of bone volume , it is not relevant if PAB is used alone or combined with β-TCP or HA/β-TCP . Clinical relevance The amount of PAB and associated donor site morbidity may be reduced by adding BSM for maxillary sinus augmentation BACKGROUND Several grafting material s have been used in sinus augmentation procedures including autogenous bone , demineralized freeze-dried bone , hydroxyapatite , β-tricalcium phosphate , anorganic deproteinized bovine bone , and combination of these and others . Yet , the issue of the optimal graft material for sinus floor augmentation is controversial . PURPOSE This prospect i ve , r and omized split-mouth study was undertaken to histomorphometrically compare a biphasic calcium phosphate ( BCP ) alloplastic bone substitute and a human bone mineral allograft ( freeze-dried bone allograft , FDBA ) in patients undergoing bilateral maxillary lateral sinus floor augmentation . MATERIAL AND METHODS Apico-coronal core biopsies were harvested at 9 months from 26 bilateral sites in 13 treated patients . Specimens were processed for histological and histomorphometrical analyses . RESULTS Newly formed bone ( NB ) was evident in all specimens with values of 27.5 % and 24.0 % at the FDBA and BCP sites , respectively ( P = .331 ) . The residual graft particle values were 12.5 % and 25.4 % ( P = .001 ) , and the connective tissue values were 60.0 % and 50.6 % , respectively . The osteoconductive value was 52.6 % for the FDBA and 26.7 % for the alloplast ( P = .001 ) . The values for the measured residual graft particles , connective tissue , and osteoconductivity , but not for NB , showed highly significant differences between the two groups . All sections in the alloplast material showed evidence of a light chronic inflammatory infiltrate , mainly comprising lymphocytes and multinucleated giant cells . CONCLUSIONS Both graft material s are suitable for sinus floor augmentation , with the allograft material being more osteoconductive OBJECTIVES The aim of this study was to evaluate the extent and quality of new bone 6 months after sinus lift with biphasic micro- and macroporous calcium phosphate combined with fibrin sealant ( MBCP-FS ) and the 1-year implant success rate in the augmented site . MATERIAL AND METHODS MBCP-FS was applied to one sinus in 96 subjects requiring augmentation for delayed dental implant placement . In subjects who required bilateral lifts ( N = 33 ) , the MBCP-FS sinus was r and omly selected ; the contralateral sinus was grafted with autologous bone ( mixed with Bio-Oss when harvested bone volume was insufficient . Panoramic views were taken periodically prior to and up to 18 months post-lift . Histomorphometric analysis was conducted on biopsies taken during implant placement 6 months after augmentation . Implant functionality and prosthesis success were assessed clinical ly 1 year after implant placement . RESULTS In MBCP-FS sinuses , 20.6 ± 8.5 % new , mainly lamellar bone was observed . Implants were placed as planned in 78/85 evaluable subjects ( 91.8 % ) 6 months after sinus lift . Graft heights remained stable 1 year after placement ; 94.7 % ( 142/150 ) of implants were functional . The amount and quality of new bone and implant success rates  with MBCP-FS were similar to autologous bone graft ( mixed with Bio-Oss in 30/31 evaluable subjects ) . MBCP-FS was safe and well-tolerated . CONCLUSIONS MBCP-FS is safe and effective in sinus floor elevation for dental implant placement , supporting bone regeneration and with high 1-year implant success rates similar to autologous bone mixed with Bio-Oss OBJECTIVES Bilateral sinus floor augmentation procedure was performed in 17 patients to study the effect of bioactive glass ( BG ) granules mixed with autologous bone ( AB ) chips on bone regeneration . The posterior part of 17 maxillary sinus was augmented with a 1:1 mixture of BG granules ( phi 800 - 1000 microm ) and AB chips harvested from the iliac crest ( BG-AB group ) . The anterior parts of the same sinus and the contralateral sinus , serving as a control ( AB group ) , were filled with AB chips alone . Trephine biopsies for histological , scanning electron microscopy ( SEM ) , and energy dispersive X-ray ( EDX ) analyses were taken from the posterior part of the sinus after 21 - 34 weeks at the time of insertion of dental implants . Additionally , six biopsies were taken from the BG-AB group and four biopsies were taken from the AB group in connection with abutment operation at 49 - 62 weeks . RESULTS Histological evaluation revealed lamellar bone growth in all the specimens . Although most of the BG granules were without bone contact in the majority of the patients in the BG-AB group , the bone lamellae were thicker than observed in the AB group . In the contact areas , bone was growing along the glass surface connecting the particles together . Histomorphometrical analysis carried out from the SEM images at 21 - 34 weeks revealed 26 % and 25 % bone in the BG-AB and the AB group , respectively . Corresponding figures for 49 - 62 weeks were 29 % for the BG-AB group and 25 % for the AB group . Bone-BG complex , i.e. the granules with intimate contact with bone , occupied 34 % of the area measured at 21 - 34 weeks and 31 % at 49 - 62 weeks . EDX analysis showed a tight contact and chemical bonding between the glass and bone . As a sign of dissolution , a few small Si-depleted areas were present in some BG granules at 21 - 34 weeks , while more and larger Si-free areas were observed in the granules at 49 - 62 weeks . CONCLUSION The results indicate that BG granules ( S53P4 ) can be used together with AB chips for sinus floor augmentation procedure , thus decreasing the amount of bone needed . Further studies concerning especially the biomechanical properties of the BG-AB complex with dental implants are needed The choice of augmentation material is a crucial factor in sinus augmentation surgery . Bovine-derived hydroxyapatite ( BHA ) and beta-tricalcium phosphate ( β-TCP ) have been used successfully in sinus augmentation procedures . Choosing one of these material s for sinus augmentation is still controversial . The aim of this clinical study was to compare the biological performance of the new BHA graft material and the well-known synthetic β-TCP material in the sinus augmentation procedure . The study consisted of 23 patients ( 12 male and 11 female ) who were either edentulous or partially edentulous in the posterior maxilla and required implant placement . A total of 23 two-step sinus-grafting procedures were performed . BHA was used in 13 patients , and β-TCP was used in 10 patients . After an average of 6.5 months of healing , bone biopsies were taken from the grafted areas . Undecalcified sections were prepared for histomorphometric analysis . The mean new bone formation was 30.13 % ± 3.45 % in the BHA group and 21.09 % ± 2.86 % in the β-TCP group ( P = .001 ) . The mean percentage of residual graft particle area was 31.88 % ± 6.05 % and 34.05 % ± 3.01 % for the BHA group and β-TCP group , respectively ( P = .047 ) . The mean percentage of soft-tissue area was 37.99 % ± 5.92 % in the BHA group and 44.86 % ± 4.28 % in the β-TCP group ( P = .011 ) . Both graft material s demonstrated successful biocompatibility and osteoconductivity in the sinus augmentation procedure . However , BHA appears to be more efficient in osteoconduction when compared with β-TCP PURPOSE The aims of the present study were to compare a novel biphasic calcium phosphate ( BCP ) with deproteinized bovine bone ( DBB ) for maxillary sinus floor augmentation in a split-mouth design and to perform a clinical follow-up of dental implants placed in the augmented sinuses . MATERIAL S AND METHODS Partially or completely edentulous patients requiring bilateral sinus augmentation were included in the study . The patients were r and omized for augmentation with BCP ( test ) and DBB ( control ) in the contralateral side . Eight months after grafting , dental implants were placed . After 3 years of graft healing , core biopsy specimens were obtained from the grafted areas for histologic and histomorphometric analyses . After 3 years of functional implant loading , implant survival/success rates and clinical indices were assessed and radiographic examination and resonance frequency analysis were performed . RESULTS Nine completely edentulous patients and two partially edentulous patients ( mean age , 67 years ) who required bilateral sinus augmentation were included in the study , and 62 implants were placed . The mean values for the area of newly formed bone in the retrieved specimens were 29 % ± 14.3 % and 32 % ± 18.0 % for BCP and DBB , respectively ; the percentage of graft particles in contact with bone was 38 % ± 10.9 % in the BCP group and 44 % ± 12.1 % in the DBB group ( no statistical significant differences between groups ) . The mean values for the area of BCP particles and DBB particles were 20 % ± 7.5 % and 24 % ± 13.5 % , respectively ( difference not significant ) . One dental implant was lost from each group , result ing in an overall implant survival rate of 96.8 % after 3 years of loading . CONCLUSION After 3 years , a similar amount of newly formed bone was present regardless of the bio material used . The choice of bio material did not seem to influence implant survival rates OBJECTIVE The combination of anorganic bovine bone ( ABB ) with platelet-rich plasma ( PRP ) has been widely used in bone regeneration procedures although its benefits are still unclear . The purpose of this study was to evaluate whether or not PRP improves the efficacy of ABB in sinus floor augmentation . In addition , we have investigated the effect of residual bone height and tobacco on implant survival in sinus augmentation procedures . PATIENT AND METHODS Eighty-seven patients recruited for this study underwent 144 sinus floor augmentation procedures using ABB alone or ABB plus PRP ( ABB+PRP ) in a r and omized clinical trial . A total of 286 implants were placed in the augmented bone , and their evolution was followed up for a period of 24 months . In order to investigate on a histological level and any adjunctive effects , we performed an ancillary study in five edentulous patients with a symmetrical severely resorbed maxilla . In these patients , a bilateral sinus augmentation was r and omly performed using ABB or ABB+PRP in a split-mouth design , and after 6 months , bone biopsies were taken from the implant sites for histological and histomorphometric analysis . RESULTS Overall , 96.2 % of ABB and 98.6 % of ABB+PRP  implant success were obtained during the monitoring period and differences were not found between sites grafted with and without PRP in the 87 patients studied . Densitometry assessment s and graft resorption were similar in both experimental groups . However , the histological and histomorphometrical analysis in the five edentulous patients revealed that bone augmentation was significantly higher in sites treated with ABB+PRP ( p < or= 0.05 ) . Another outcome from our study is that the lack of initial bone support ( p < or= 0.05 ) and smoking ( p=0.05 ) appeared to have a negative effect on the treatment success , which was accentuated when both circumstances coincided . CONCLUSIONS PRP is not a determining factor for implant survival in sinus lifting procedures . However , this study revealed that PRP can improve the osteoconductive properties of ABB by increasing the volume of new bone formed . Moreover , in sinus augmentation procedures the implant 's survival rate appears to be more influenced by the residual bone height or by tobacco than by the type of bone graft PURPOSE The aim of this study was to compare a bovine bone substitute ( Bio-Oss ) to autogenous bone with respect to its value as a material for sinus augmentation . MATERIAL S AND METHODS In 10 beagle dogs 12 months of age , the 3 maxillary premolars were extracted on both sides . Six weeks later , 2 cavities of predefined size were produced in the region of the nasal cavity . The antral window was 25 mm long and had a vertical extension of 7 mm . Two Frialit-2 implants ( 3 x 8 mm ) were placed in each bone defect ( n = 20 ) . Every implant was primarily stable because of fixation in native bone . In each maxilla , 1 bone defect was filled with autogenous bone harvested from the m and ible and 1 was filled with Bio-Oss ( material selected at r and om ) . The animals were sacrificed at 90 and 180 days , and histologic specimens were examined and the results subjected to statistical analysis by the Wilcoxon test for paired observations . RESULTS No healing problems were observed . Histologically , after 90 days the volume of the augmentation showed a reduction of 14.6 + /- 4.4 % within the Bio-Oss group and 3.8 + /- 2.5 % in the group with autogenous bone . Bone-implant contact of 52.16 + /- 13.15 % in the Bio-Oss group and 60.21 + /- 11.46 % in the autogenous bone group was observed . At 180 days , the Bio-Oss group showed bony ingrowth of the substitute , whereas in the autogenous group a differentiation from original bone could no longer be made . The volume reduction was 16.5 + /- 8.67 % in the Bio-Oss group and 39.8 + /- 16.14 % in the autogenous group . Bone-implant contact of 63.43 + /- 19.56 % in the Bio-Oss group and 42.22 + /- 12.80 % in the autogenous bone group was measured . DISCUSSION AND CONCLUSION The results indicated that because of the nonresorptive properties of the bone substitute Bio-Oss , regeneration of the defects is achievable . It was demonstrated that the bone substitute seemed to behave as a permanent implant . The volume of the area augmented by autogenous bone decreased over the observation period PURPOSE The purpose of this work was to evaluate the potential of substituting autogenous bone ( AB ) by bone marrow aspirate concentrate ( BMAC ) . Both AB and BMAC were tested in combination with a bovine bone mineral ( BBM ) for their ability of new bone formation ( NBF ) in a multicentric , r and omized , controlled , clinical and histological noninferiority trial . MATERIAL S AND METHODS Forty-five severely atrophied maxillary sinus from 26 patients were evaluated in a partial cross-over design . As test arm , 34 sinus of 25 patients were augmented with BBM and BMAC containing mesenchymal stem cells . Eleven control sinus from 11 patients were augmented with a mixture of 70 % BBM and 30 % AB . Biopsies were obtained after a 3 - 4-month healing period at time of implant placement and histomorphometrically analyzed for NBF . RESULTS NBF was 14.3%±1.8 % for the control and nonsignificantly lower ( 12.6%±1.7 % ) for the test ( 90 % confidence interval : -4.6 to 1.2 ) . Values for BBM ( 31.3%±2.7 % ) were significantly higher for the test compared with control ( 19.3%±2.5 % ) ( p<0.0001 ) . Nonmineralized tissue was lower by 3.3 % in the test compared with control ( 57.6 % ; p=0.137 ) . CONCLUSIONS NBF after 3 - 4 months is equivalent in sinus , augmented with BMAC and BBM or a mixture of AB and BBM . This technique could be an alternative for using autografts to stimulate bone formation PURPOSE To test our null hypothesis stating that the mixture of autogenous cortical bone scrapings and bovine bone mineral ( BBM ) in a ratio of 1:4 , compared with BBM alone , would have no significant effect on new bone formation 4 months after maxillary sinus floor augmentation . PATIENTS AND METHODS Twenty-four patients presenting with alveolar bone height of less than 5 mm in the narrowest zone between the sinus floor and alveolar crest were r and omly assigned to 2 treatment groups in this r and omized controlled trial . We augmented 12 maxillary sinuses with a mixture of BBM and cortical autogenous bone graft , which was collected from the lateral wall of the maxillary sinus by a bone scraper , and 12 maxillary sinuses with BBM alone . Four months postoperatively , new bone formation in the augmented sinus sites was evaluated through bone scintigraphy , as well as histologic and histomorphometric analyses of the biopsy specimens obtained during implant placement . Data were statistically analyzed by independent- sample s t test . RESULTS Scintigraphically detectable new bone formation did not differ significantly between the groups ( P > .05 ) . Histologic findings showed that the new bone bridged between BBM particles and BBM underwent resorption by osteoclasts with or without the addition of autogenous bone graft . According to histomorphometric findings , the difference between the percentages of newly formed bone in the sinuses augmented with graft mixture ( 25.73 % ) and BBM alone ( 24.19 % ) was statistically nonsignificant ( P > .05 ) . CONCLUSIONS The addition of autogenous cortical bone scrapings to BBM in a ratio of 1:4 , compared with BBM alone , does not markedly increase new bone formation 4 months after maxillary sinus lifting BACKGROUND Several treatment options exist for the implant-supported rehabilitation of edentulous posterior maxilla . PURPOSE To compare maxillary sinus floor augmentation associated to st and ard length implants , with direct placement of implants of reduced length in the available residual bone . MATERIAL S AND METHODS Patients with edentulous posterior maxilla and a residual height of 4 - 7 mm were r and omly allocated to the test ( short implants [ SIs ] , 6.5 to 8.5 mm long ) or the control ( sinus augmentation [ SA ] and implants ≥10 mm long ) group . Anorganic bovine bone was the grafting material for the control group . In both groups pure platelet-rich plasma was used to bioactivate implant surface prior to insertion . Implant and prosthesis survival , clinical variables , radiographic bone level change , quality of life , and patient satisfaction were assessed . RESULTS Twenty-five patients were treated in the control group ( 58 st and ard length implants ) and 27 in the test group ( 42 SIs ) . After 3 years of follow-up no implant failure and biological or mechanical complications were recorded . Marginal bone loss , soft tissue , and oral hygiene parameters were similar in the 2 groups at both 1 and 3 years ' follow-up . Postoperative pain , swelling and other symptoms and daily activities were better in the SIs group than in the SA group , while patients ' satisfaction after 1 year was similar . CONCLUSIONS In spite of comparable medium-term clinical and radiographic outcomes , when the residual ridge height is sufficient for a safe placement , SIs may be preferred due to simplified protocol , less invasiveness , shorter treatment time , and reduced postoperative discomfort as compared to SA Abstract The aim of this r and omized controlled study was to comparatively analyze the new bone ( NB ) , residual bone , and graft-bone association in bone biopsies retrieved from augmented maxillary sinus sites by histomorphometry and microcomputed tomography ( MicroCT ) in a split-mouth model to test the efficacy of porous titanium granules ( PTG ) in maxillary sinus augmentation . Fifteen patients were included in the study and each patient was treated with bilateral sinus augmentation procedure using xenograft ( equine origine , granule size 1000–2000 & mgr;m ) and xenograft ( 1 g ) + PTG ( granule size 700–1000 & mgr;m , pore size > 50 & mgr;m ) ( 1 g ) , respectively . After a mean of 8.4 months , 30 bone biopsies were retrieved from the implant sites for three-dimensional MicroCT and two-dimensional histomorphometric analyses . Bone volume and vital NB percentages were calculated . Immediate after core biopsy , implants having st and ard dimensions were placed and implant stability quotient values were recorded at baseline and 3 months follow-up . There were no significant differences between groups according to residual bone height , residual bone width , implant dimensions , and implant stability quotient values ( baseline and 3 months ) . According to MicroCT and two-dimensional histomorphometric analyses , the volume of newly formed bone was 57.05 % and 52.67 % , and 56.5 % and 55.08 % for xenograft + PTG and xenograft groups , respectively . No statistically significant differences found between groups according to NB percentages and higher Hounsfield unit values were found for xenograft + PTG group . The findings of the current study supports that PTG , which is a porous , permanent nonresorbable bone substitute , may have a beneficial osteoconductive effect on mechanical strength of NB in augmented maxillary sinus PURPOSE Implant placement in the posterior maxilla may often be contraindicated because of insufficient bone volume and the presence of the maxillary sinus . In these situations , sinus floor lifting and grafting frequently have been proposed as the best treatment . The aim of this study was to compare histologically the use of 100 % autogenous bone versus a combination of autogenous bone and corticocancellous pig bone for maxillary sinus augmentation . MATERIAL S AND METHODS Eighteen patients requiring bilateral maxillary sinus augmentation were selected for this study . Bone for grafting was harvested from the iliac crest . Each patient received 100 % autogenous bone in 1 r and omly selected sinus ( control side ) and a 1:1 mixture of autogenous bone and corticocancellous pig bone particles in the contralateral sinus ( test side ) . Five months after the augmentation procedure , bone biopsy specimens were taken at the time of implant placement . RESULTS No complications were observed during the surgical procedures ; all patients healed uneventfully . No signs or symptoms of maxillary sinus disease were observed during the 5 months after surgery . No significant differences in bone percentages were observed in the bone biopsies from test and control sides . DISCUSSION AND CONCLUSION It could be concluded from this study that corticocancellous pig bone particles can be successfully used in a 1:1 mixture with autogenous bone from the iliac crest for maxillary sinus augmentation in cases of severely atrophic maxilla INTRODUCTION This investigation was design ed to compare the histomorphometric results from sinus floor augmentation with anorganic bovine bone ( ABB ) and a new biphasic calcium phosphate , Straumann Bone Ceramic ( BCP ) . MATERIAL S AND METHODS Forty-eight maxillary sinuses were treated in 37 patients . Residual bone width was > or = 6 mm and height was > or =3 mm and < 8 mm . Lateral sinus augmentation was used , with grafting using either ABB ( control group ; 23 sinuses ) or BCP ( test group ; 25 sinuses ) ; sites were r and omly assigned to the control or test groups . After 180 - 240 days of healing , implant sites were created and biopsies taken for histological and histomorphometric analyses . The parameters assessed were ( 1 ) area fraction of new bone , soft tissue , and graft substitute material in the grafted region ; ( 2 ) area fraction of bone and soft tissue components in the residual alveolar ridge compartment ; and ( 3 ) the percentage of surface contact between the graft substitute material and new bone . RESULTS Measurable biopsies were available from 56 % of the test and 81.8 % of the control sites . Histology showed close contact between new bone and graft particles for both groups , with no significant differences in the amount of mineralized bone ( 21.6+/-10.0 % for BCP vs. 19.8+/-7.9 % for ABB ; P=0.53 ) in the biopsy treatment compartment of test and control site . The bone-to-graft contact was found to be significantly greater for ABB ( 48.2+/-12.9 % vs. 34.0+/-14.0 % for BCP ) . Significantly less remaining percentage of graft substitute material was found in the BCP group ( 26.6+/-5.2 % vs. 37.7+/-8.5 % for ABB ; P=0.001 ) , with more soft tissue components ( 46.4+/-7.7 % vs. 40.4+/-7.3 % for ABB ; P=0.07 ) . However , the amount of soft tissue components for both groups was found not to be greater than in the residual alveolar ridge . DISCUSSION Both ABB and BCP produced similar amounts of newly formed bone , with similar histologic appearance , indicating that both material s are suitable for sinus augmentation for the placement of dental implants . The potential clinical relevance of more soft tissue components and different resorption characteristics of BCP requires further investigation The purpose of this study was to histomorphometrically evaluate the percentage of vital bone after grafting of maxillary sinuses using two different concentrations of recombinant human bone morphogenetic protein/acellular collagen sponge ( rhBMP-2/ACS ) combined with mineralized cancellous bone allograft ( MCBA ) and to compare the results to a control sinus grafted with MCBA only .  Thirty-six sinuses in 18 patients had two of three of the graft combinations including : ( 1 ) control , MCBA only ; ( 2 ) test one , MCBA + 5.6 mL of rhBMP-2/ACS ( containing 8.4 mg of rhBMP-2 ) ; or ( 3 ) test two , MCBA + 2.8 mL of rhBMP-2/ACS ( containing 4.2 mg of rhBMP-2 ) . Histologic cores were taken 6 to 9 month following sinus augmentation . The results showed no statistically significant differences in vital bone between the two test groups compared to the control sinus group treated with MCBA alone . Future studies involving more cases and evaluating survival of implants placed in these augmented sinuses are needed to verify the results of this r and omized prospect i ve study BACKGROUND Surgical techniques as sinus floor augmentation have made it possible to increase the bone volume of the posterior maxilla so that implant placement may be feasible . A large variety of bone grafting material s have been utilized for sinus floor augmentation . A good alternative is allograft . Fresh frozen bone is harvested from live or cadaveric donors and then immediately frozen and stored at -80 ° C . To date , studies about the effect of fresh frozen bone are scarce . OBJECTIVE Evaluation of new bone formation , following maxillary sinus grafting with autograft vs. fresh frozen allograft . MATERIAL S AND METHODS A split-mouth edentulous design including 15 patients was used .  Sinus floor augmentation was carried out using either autogenous bone harvested from the ramus area or fresh frozen bone from allogeneic femoral heads . The choice was determined r and omly , using a r and omized table . The grafted sinus was left to heal for 6 months . Biopsies were harvested from the lateral wall . The biopsies were used for bone histology and histomorphometric analysis . After collection of the biopsy , dental implants were placed . After a healing period of 6 months , the implants were loaded . RESULTS Implant survival , histology , and histomorphometry of sinuses grafted with autogenous or fresh frozen bone were similar . The new bone formation took place predominantly around and in-between particles . CONCLUSIONS The findings of the present study support the use of fresh frozen bone allografts for sinus floor augmentation Purpose : The purpose of this split-mouth controlled study was to evaluate and compare the amount of vital bone after lateral sinus lift surgery using either a mixture of pure platelet concentrate and deproteinized bovine bone mineral ( test group ) or solely deproteinized bovine bone as grafting material ( control group ) . Material s and Methods : Six patients with edentulous posterior maxilla and a residual ridge height of less than 4 mm were recruited in this study . Six months after grafting procedure , 2 bone biopsies per patient were taken bilaterally from the anterolateral sinus wall . Histological and histomorphometrical analysis was carried out . Results : A total of 10 sinus surgeries in 5 patients were analyzed . The mean percentage of vital bone was 22.72 % ± 9.21 % ( range , 11.45%–33.30 % ) in the control group and 30.70 % ± 7.89 % ( range , 18.30%–39.99 % ) in the test group . Conclusion : The adjunct of pure platelet-rich plasma to deproteinized bovine bone mineral may enhance vital bone formation in the first 6 months after sinus floor augmentation . However , no statistically significant difference was found between groups ( P = 0.18 ) PURPOSE The histomorphometric results of sinus floor augmentation with deproteinized bovine bone ( DBB ) and a new fully synthetic bone substitute , poly(lactic-co-glycolic acid/hydroxyapatite ) ( PLGA/HA ) , were compared in humans . MATERIAL S AND METHODS Twelve maxillary sinuses of eight patients requiring major maxillary sinus floor augmentation and free of concomitant conditions ( ASA scores 1 and 2 ) were studied . Lateral sinus augmentation was performed using DBB or PLGA/HA grafts ; sites were r and omly assigned to control or test groups . Patients were reexamined approximately 6 months after grafting using cone beam computed tomography scans , and biopsy sample s were harvested from implant sites . Total bone volume , residual graft material volume , and new bone volume were assessed . RESULTS Healing times were similar between groups . Measurable biopsy specimens were available from four of the test sites and six of the control sites . PLGA/HA grafts showed no trace of graft material , whereas DBB grafts had a mean graft area of 16.5 % ( P < .05 ) . Mean percent newly formed bone tended to be greater for PLGA/HA ( 44.45 % ) than for DBB ( 27.51 % ) . Mean total volume percent did not differ significantly : PLGA/HA = 44.45 % , DBB = 44.10 % . CONCLUSION DBB and PLGA/HA produced similar total bone volumes . PLGA/HA appeared to be completely resorbed , whereas DBB presented residual graft material . With the limitations due to the small sample size , both material s were suitable for sinus floor augmentation Purpose : Validation of platelet-rich plasma ( PRP ) system and assessing its enhancing effect on the healing of  iliac crest grafts before implant placement . Material s and Methods : Patients r and omly allocated to test ( n = 13 ) and control ( n = 9 ) groups .  Iliac crest grafts were mixed with PRP in the test group . Tetracycline labeling preceded implant placement . Bone sample s were harvested for histomorphometrical analysis . Platelet and growth factor quantifications were performed . Analysis : Data were analyzed using SPSS software package . Independent t test was used and statistical significance was set at 5 % . Results : The PRP group showed significantly higher platelet counts , PDGF-BB , and TGF-&bgr;1 concentrations . Tendency to higher volume of woven bone was observed in the PRP group ( 13 ± 11 vs 4 ± 6 , P = 0.1 ) . Histomorphometry showed increased seam separation in the PRP group ( 8.8 ± 9 & mgr;m vs 1.5 ± 3 & mgr;m , P = 0.039 ) . Remodeling activity was higher in PRP-woven bone sections and comparable in trabecular sections . Conclusion : PRP significantly increased platelet and growth factor concentrations and was of possible enhancing effect on the rate of bone formation at 3 to 4 months of grafting . The clinical significance of this enhancement is yet to be established BACKGROUND The potential effects of adding pure platelet-rich plasma ( P-PRP ) or platelet-rich fibrin ( PRF ) to beta-tricalcium phosphate ( β-TCP ) graft substitute on bone formation and regeneration after maxillary sinus-floor elevation remains unclear . PURPOSE To compare the histologic and histomorphometric outcomes of maxillary sinus-floor augmentation among β-TCP alone , P-PRP-mixed β-TCP , and PRF-mixed β-TCP . MATERIAL AND METHODS In this r and omized clinical trial , elevated sinus cavities were grafted with β-TCP ( the control group ) , P-PRP-mixed β-TCP ( the P-PRP group ) , and PRF-mixed β-TCP ( PRF group ) . The sample was composed of 26 patients : 9 subjects in control and P-PRP groups , and 8 subjects in PRF group . After a 6-month , healing period , bone graft biopsies were harvested prior to implant placement , and the specimens were analyzed . The main outcome variables included findings of histologic and histomorphometric analyses of the bone graft biopsies . The data were analyzed by ANOVA and Tukey HSD tests . RESULTS The mean percentages of new bone formations were 33.40 ± 10.43 % , 34.83 ± 10.12 % , and 32.03 ± 6.34 % in control , P-PRP , and PRF groups , respectively , with no significant differences ( P > .05 ) . Mean percentages of residual graft particle area were 30.39 ± 10.29 % , 28.98 ± 7.94 % , and 32.66 ± 7.46 % in control , P-PRP , and PRF groups , respectively , with no significant differences ( P > .05 ) . The mean percentages of soft-tissue area were 36.21 ± 10.59 % , 36.19 ± 13.94 % , and 35.31 ± 10.81 % in control , P-PRP , and PRF groups , respectively , with no significant differences ( P > .05 ) . Mean densities of osteoblasts , osteoclasts , osteocytes , and capillary vessels showed insignificant difference between groups ( P > .05 ) , but osteoprogenitor cells were lower and inflammatory cells were higher in the PRF group than those in other groups ( P < .01 ) . Biopsies of P-PRP , PRF , and control groups showed similar composition and distribution of histologic structures . CONCLUSION These findings suggested that adding P-PRP or PRF to β-TCP graft substitute was not beneficial on new bone formation and regeneration , and P-PRP plus β-TCP or PRF plus β-TCP is not superior to β-TCP alone PURPOSE Two different graft material s , beta-tricalcium phosphate ( Cerasorb ) and autogenous bone , were used in the same patient . The objective was to determine whether donor site morbidity could be avoided by using pure-phase beta-tricalcium phosphate ( Cerasorb ) . MATERIAL S AND METHODS Bilateral sinus grafting was performed on 20 selected patients ;  Cerasorb was used on the experimental side , and autogenous bone was used on the control side . In each patient , one side was r and omly design ated the experimental side . In 10 of the 20 patients , the maxilla reconstruction included sinus grafting and onlay bone grafting . Implants were placed 6 months after the procedure . In addition to routine panoramic radiographs , in 10 of the 20 patients , 2- and 3-dimensional computerized tomographic examinations were performed pre- and postoperatively and after implantation . Eighty bone biopsy specimens were taken at the time of implant placement . RESULTS Histologically and histomorphometrically , there was no significant difference between the experimental and control grafts in terms of the quantity and rate of ossification . For each histologic sample , the total surface area , the surface area that consisted of bone , and the surface area that consisted of graft material were measured in mm2 , and bone and graft material were analyzed as percentages of the total . The mean percentage bone areas were 36.47 % + /- 6.9 % and 38.34 % + /- 7.4 % , respectively ; the difference was not significant ( P = .25 ) . DISCUSSION AND CONCLUSION Comparisons with other studies reveal that beta-tricalcium phosphate ( Cerasorb ) is a satisfactory graft material , even without autogenous bone BACKGROUND AND OBJECTIVES The atrophic posterior maxilla often requires restoration of the alveolar ridge due to a lack of bone quantity and quality before dental implant placement . The aim of this study was to verify the hypothesis that platelet-rich plasma ( PRP ) has an influence on bone density in the maxilla after sinus floor elevation in combination with autologous cancellous bone from the iliac crest . Therefore , a r and omized , prospect i ve , controlled trial was set up in two centres . STUDY DESIGN AND METHODS Fifty-three patients who underwent osteoplastic bone grafting for sinus floor elevation were included . The intervention group was treated with defined concentrations of PRP in addition to transplanted bone . Bone biopsy was performed 4 months after augmentation . Bone volume was then measured using the histomorphometric parameter bone volume . RESULTS The histomorphometric evaluation of the biopsies did not indicate superiority of any of the treatments in terms of bone volume . CONCLUSION Topical use of PRP did not improve maxillary bone volume either clinical ly relevant or statistically significant compared to that in conventionally treated patients . The use of PRP to support bone regeneration can not be recommended as a st and ard method for maxillary augmentation Key Summary Points When r and omized trials have been done for several different treatment options for the same condition , it is important to underst and the pattern of all these comparisons . This pattern of comparisons is called the geometry of the treatment network . Existing indices can be used to measure the diversity and co-occurrence of treatments . These measures are the probability of interspecific encounter index and the co-occurrence score , respectively . An evaluation of 18 treatment networks for different conditions with 4 to 16 treatments each reveals distinct geometries in clinical evidence . The geometry of a treatment network may reflect both rational choices and various preference biases . Many diseases have several competing treatments ; however , clinical research , systematic review s , and meta-analyses have tended to focus on assessing the merits of 1 treatment at a time or , at most , the relative merits of 2 different regimens . This approach provides only a partial view of the possible wealth of treatment options for a given condition , without addressing the relative merits of all available options . The comparisons between different treatments constitute a network . Appropriate methodology has been developed for combining the data from a network of trials ( 14 ) , allowing the incorporation of evidence from all direct and indirect comparisons toward estimating summary treatment effects . We do not address the techniques here ; rather , we focus on the patterns ( geometry ) of direct comparisons within each network and what those patterns might mean . When examining a treatment network , some key questions need to be addressed . First , are there few or many treatments and , if many , are all treatments represented equally in the network or have some been disproportionately studied ? Second , are some pairs preferentially studied , whereas evidence is systematic ally lacking for some other comparisons ? In the terminology of the ecological sciences , these issues pertain to diversity and co-occurrence , respectively . We cumulatively call these properties the geometry of the network . A network 's geometry may reflect the wider clinical context of the evidence and may be shaped by rational choices for treatment comparators or by specific biases . In another study ( 2 ) , we preliminarily adapted metrics from the ecological literature to describe the diversity and co-occurrence features of treatment networks . Here , we extend and further operationalize these metrics by demonstrating how exploration of network geometry may help with interpretation of the evidence on multiple competing treatments for the same indication . Methods Network Geometry The diagram of all comparisons between treatments in a network can take many different shapes . At one extreme , the same comparator is used in all trials . This network resembles a star , with the common reference st and ard ( often placebo or no treatment ) in its center . At the other extreme , all treatments are compared with all others and no particular treatment or comparison is studied more often than the others . A wide range of intermediate situations is possible between these 2 extremes . Comparator Preference Bias Network geometry is determined by many parameters . Networks may vary in complexity from the simple ( such as a network in which only 3 treatment options exist ) to the very complex ( such as a network involving several dozens of treatments ) . Networks may also be asymmetric , meaning that certain treatments or comparisons are represented more heavily than others . Investigators ' preference for specific treatments may be dictated by various factors , including how long a treatment has been available for testing , the treatment 's perceived effectiveness and safety , how actively its development agenda has been pushed by its sponsors , and whether regulatory m and ates force or discourage its use ( 5 ) . When a treatment has been the reference st and ard for a long time , it may become widely accepted that investigators should always consider it as one of the compared options . Finally , what is studied is not necessarily what is eventually published : Selective reporting biases , publication bias , time lag bias , and other selection forces further affect the amount of publicly visible evidence on specific treatments ( 6 , 7 ) . Similar forces may also shape the relative amount of evidence for specific comparisons within the network . In addition , head-to-head comparisons between effective agents may be avoided in some fields ; the agents ' sponsors may not wish to risk an agent being declared inferior and losing its market share . Selecting straw man comparators may result in exaggerated treatment effects , particularly in industry-sponsored trials ( 810 ) . The extent of these various selection forces are expected to vary among networks . We cumulatively call these selection forces comparator preference bias . Evaluation of network geometry and the accompanying asymmetry may help address such bias . Underst and ing the underlying reasons requires careful examination of each network and knowledge of the field and the circumstances under which its evidence was accumulated . Data Sources and Selection We search ed PubMed through April 2007 by using the following algorithms : network AND meta- analysis , multiple treatment AND meta- analysis , indirect comparison AND meta- analysis , and indirect AND meta- analysis . We also search ed Thompson ISI Web of Knowledge for studies that cited method ological articles on multiple treatments meta- analysis ( 1 , 3 , 4 , 11 ) . We limited our search to English- language articles . We included meta-analyses of r and omized , controlled trials that involved at least 4 different treatments . The term treatment is used here to denote any kind of intervention ( medical , surgical , or other ) under any circumstances ( therapeutic or preventive ) , as well as no treatment or placebo . Where meta-analysts merged different schedules or doses of the same regimen or similar agents , we respected this merging . We excluded meta-analyses when their eligibility criteria excluded comparisons among treatments otherwise considered in the network . We did not consider the simplest networks of only 3 different treatments , because those have been extensively studied elsewhere ( 12 ) . Data Extraction One author extracted data about the main outcome and the condition studied ; the number of studies per comparison ; and , when available , the number of individuals per r and omized group . A second review er checked the extracted information . Statistical Analysis Diversity A network has less diversity when it contains fewer treatments . Among networks that contain the same number of treatments , a network has less diversity when the treatments are not equally represented ( some treatments are used more often than others ) . We use the probability of interspecific encounter ( PIE ) index , which is the probability that 2 r and omly sample d treatment groups from the network ( without replacement ) have been allocated to 2 different treatments . The PIE index is a continuous variable that decreases with increasing unevenness ; for operational purpose s , values of 0.75 or less can be considered to reflect limited diversity ( 13 ) . We also use the PIE index , which is the value of PIE divided by the maximum value that PIE can take for the given number of studies . The Appendix further discusses some properties of PIE and PIE . Co-occurrence Co-occurrence reflects whether particular pairwise comparisons of specific treatments are preferred or avoided . The number of checkerboard units shows how many times 2 treatments could have been compared , given their relative frequencies . The C-score reflects the overall average tendency of the treatments not to occur together . The statistical significance of the C-score is measured by using a permutations procedure . A P value less than 0.05 is considered to represent significant co-occurrence ; however , a more liberal threshold of less than 0.10 may also be used because the test tends to be underpowered with few trials ( 13 ) . We plotted the number of checkerboard units for each comparison in networks that showed significant co-occurrence . Visual inspection of the plot can reveal whether the apparent co-occurrence is due to a particular comparison that is highly avoided or to a small degree of selectiveness in many of the comparisons . All calculations were performed by using EcoSim software , version 7 ( 14 ) . Results Eligible Treatment Networks We retrieved 41 potentially eligible articles . Of those , 12 included fewer than 4 treatments , 8 excluded specific comparisons among otherwise eligible treatments , 1 did not form a network , 1 used some data for a method ological project but the network could not be reconstructed , and 1 used a subset of a network presented elsewhere . We included 18 eligible networks ( Figure 1 and Appendix Table 1 ) ( 3 , 1531 ) . Most of these networks were published very recently ( 2 in 1997 to 2000 , 5 in 2001 to 2004 , and 11 in 2005 to 2007 ) . With 1 exception ( 25 ) , all networks addressed effectiveness . Figure 1 . Eligible treatment networks . Shaded nodes indicate placebo or no active treatment . The thickness of the lines is proportional to the number of trials addressing each specific comparison . A. Star-shaped networks . B. Nonstar-shaped networks with limited diversity and significant co-occurrence . C. Nonstar-shaped networks with limited diversity and nonsignificant co-occurrence . D. Networks with considerable diversity and significant co-occurrence . E. Networks with considerable diversity and nonsignificant co-occurrence . ACE-i = angiotensin-converting enzyme inhibitor ; AES = actinomycin Deluting stents ; ARB = angiotensin-receptor blocker ; BMS = bare-metal stents ; CCB = calcium-channel blockers ; EES = everolimus-eluting stents ; GART = genotypic antiretroviral resistance testing ; ip = intraperitoneal ; MES = mycophenolate-eluting stents ; PART = phenotypic antiretroviral resistance testing ; PES = paclitaxel-eluting stents ; SES = OBJECTIVES To evaluate the effect of leukocyte and platelet-rich fibrin ( L-PRF ) in combination with deproteinized bovine bone mineral ( DBBM ) on bone regeneration in maxillary sinus augmentation . MATERIAL AND METHODS Thirteen patients ( nine males and four females , mean age ± SD ; 49.92 ± 10.37 ) were enrolled to the study . 26 maxillary sinus augmentation procedures were r and omly performed using DBBM and L-PRF mixture ( test ) or DBBM alone ( control ) in a split-mouth design . The same surgical procedures were performed in both groups , and bone biopsies were harvested from the implant sites 6 months postoperatively for histological and histomorphometric evaluations as the primary outcome of the study . Implants were placed and then loaded in the augmented sites after 6 months . The secondary outcomes included clinical and radiographic data and were obtained pre- and postoperatively . RESULTS There was no qualitative difference in histological analyses among the groups . In all sample s , a newly formed bone was in direct contact with the residual material . The percentages of newly formed bone ( test ; 21.38 ± 8.78 % and control ; 21.25 ± 5.59 % ) , residual bone graft ( test ; 25.95 ± 9.54 % and control ; 32.79 ± 5.89 % ) , bone graft in contact with the newly formed bone ( test ; 47.33 ± 12.33 % and control ; 54.04 ± 8.36 % ) , and soft tissue ( test ; 52.67 ± 12.53 % and control ; 45.96 ± 8.36 % ) were similar among the groups ( p < .05 ) . Similar radiographic bone height in the augmented area was observed , and implant survival rate was 100 % for both groups . CONCLUSIONS Both techniques were effective for maxillary sinus augmentation , and after 6 months of healing , the addition of L-PRF in DBBM did not improve the amount of regenerated bone or the amount of the graft integrated into the newly formed bone under histological and histomorphometric evaluation The objective of the present study was to test the hypothesis that the addition of hyaluronic acid-based matrix to collagenated heterologous bone graft for sinus augmentation would enhance bone formation compared to collagenated heterologous bone graft alone in the early healing period , by micro-computed tomography and histomorphometry . Thirteen systemically healthy patients requiring bilateral two-stage maxillary sinus augmentation ( residual crest height≤4 mm ) were enrolled in this split-mouth prospect i ve r and omized controlled study . One sinus side as a control group was grafted with only collagenated heterologous bone graft ; the other region as a test group was grafted with hyaluronic matrix and collagenated heterologous bone graft . Bone biopsy sample s were taken after 4 months during the dental implant surgery and analyzed using micro-computed tomography and histomorphometric parameters . According to the micro-computed tomography and histomorphometric results , a significantly higher percentage of new bone was observed in the test group when compared to the control group after 4 months of healing . This study confirmed the hypothesis that the addition of hyaluronic matrix to collagenated heterologous bone graft for sinus augmentation enhances bone formation compared to collagenated heterologous bone graft alone in the early healing period OBJECTIVES The aim of this prospect i ve , multicenter , r and omized clinical trial was to evaluate histologically the outcome of maxillary sinus lift augmentation with a recombinant human growth and differentiation factor-5-coated β-tricalcium phosphate ( rhGDF-5/β-TCP ) or with a β-TCP and autogenous bone ( β-TCP/AB ) composite . MATERIAL AND METHODS Thirty-one patients requiring unilateral maxillary sinus floor augmentation ( residual alveolar bone height < 5 mm ) were r and omly allocated in three treatment groups : ( a ) rhGDF-5/β-TCP and a 3-month healing period , ( b ) rhGDF-5/β-TCP and a 4-month healing period , and ( c ) β-TCP and intra-oral corticocancellous autologous bone ( at 1:1 ) and a 4-month healing period . Cylindrical biopsies were harvested by means of a trephine bur during implant site preparation and evaluated histologically and histometrically . RESULTS One patient withdrew from the study before implant placement ; 66 implants were inserted in the remaining 30 patients . Four out of 47 ( 8.5 % ) implants failed in patients treated with rhGDF-5/β-TCP .  The proportion of newly formed bone was similar among groups and averaged 31.4 % ( ± 17 % ) in the rhGDF-5/β-TCP/3-month healing group , 28 % ( ± 15.5 % ) in the rhGDF-5/β-TCP/4-month healing group , and 31.8 % ( ± 17.9 % ) in the β-TCP/AB group . The proportion of remaining β-TCP averaged 12.6 % ( ± 14.4 % ) in the rhGDF-5/b-TCP/3-month group , 6.6 % ( ± 6.3 % ) in the rhGDF-5/b-TCP/4-month group , and 16.5 % ( ± 12.3 % ) in the β-TCP/AB group . The new bone was primarily woven and characterized by slender trabeculae and narrow osteoid zones , and in many instances bone was in contact with residual bio material particles . Presence of AB particle remnants was only trivial , while minimal amounts of inflammation were observed only in a few cases . CONCLUSION Sinus augmentation with rhGDF-5/β-TCP result ed in comparable amounts of new bone and of similar quality as those obtained with a β-TCP/AB composite graft
The purpose of this network meta- analysis was to identify the most effective bio material s producing higher new bone formation ( NBF ) and lower residual graft ( RG ) and connective tissue ( CT ) following maxillary sinus augmentation ( MSA ) , and to generate a ranking based on their performance .