Maxillary sinus floor elevation surgery with BioOss® mixed with a bone marrow concentrate or autogenous bone: test of principle on implant survival and clinical performance

Stem cell therapies for periodontal tissue regeneration: A meta-analysis of clinical trials

Objective

Stem cell therapy in periodontal tissue regeneration has reported optimistic regenerative results; evidence supporting its superiority over conventional methods is still ambiguous. Therefore, this meta-analysis aims to evaluate the therapeutic effects of stem cells in human periodontal regeneration.

Design

A literature search was conducted to retrieve relevant articles on periodontal regeneration in stem cell therapy. A meta-analysis of the studies was conducted using the Stata software.

Results

Fifteen studies that examined the effect of stem cell therapies on periodontal tissue regeneration in 369 patients were selected from databases. Regardless of the various types of cells, both odontogenic (periodontal ligament, dental pulp, gingiva stem cell) and non-odontogenic (bone marrow, periosteum-derived, and umbilical cord stem cells), the cell therapies witnessed significant improvements in terms of clinical attachment level (SMD, -0.67; 95CI, -0.90 to -0.43), probing depth (SMD, -0.76; 95% CI, -1.21 to - 0.31), radiographic intrabony defect depth (SMD, -0.87; 95% CI, -1.52 to -0.23), and histomorphometric analysis of mineralized bone (SMD, 0.80; 95% CI, 0.42 to 1.19) when compared to traditional without-cell treatment in patients. However, evidence on gingival recession, alveolar thickness gain, bone mineral density of bone core, and bone volume fraction of bone core outcomes did not reach statistical significance.

Conclusions

Evidence suggests that the implementation of stem cell therapies in reconstructing compromised gingiva and alveolar bone tissue produces positive outcomes compared with conventional approaches. However, further well-designed investigations are needed to comprehensively identify the most effective source of cells and biomaterials for each case.

Clinical and patient-reported outcomes of tissue engineering strategies for periodontal and peri-implant reconstruction

Scientific advancements in biomaterials, cellular therapies, and growth factors have brought new therapeutic options for periodontal and peri-implant reconstructive procedures. These tissue engineering strategies involve the enrichment of scaffolds with living cells or signaling molecules and aim at mimicking the cascades of wound healing events and the clinical outcomes of conventional autogenous grafts, without the need for donor tissue. Several tissue engineering strategies have been explored over the years for a variety of clinical scenarios, including periodontal regeneration, treatment of gingival recessions/mucogingival conditions, alveolar ridge preservation, bone augmentation procedures, sinus floor elevation, and peri-implant bone regeneration therapies. The goal of this article was to review the tissue engineering strategies that have been performed for periodontal and peri-implant reconstruction and implant site development, and to evaluate their safety, invasiveness, efficacy, and patient-reported outcomes. A detailed systematic search was conducted to identify eligible randomized controlled trials reporting the outcomes of tissue engineering strategies utilized for the aforementioned indications. A total of 128 trials were ultimately included in this review for a detailed qualitative analysis. Commonly performed tissue engineering strategies involved scaffolds enriched with mesenchymal or somatic cells (cell-based tissue engineering strategies), or more often scaffolds loaded with signaling molecules/growth factors (signaling molecule-based tissue engineering strategies). These approaches were found to be safe when utilized for periodontal and peri-implant reconstruction therapies and implant site development. Tissue engineering strategies demonstrated either similar or superior clinical outcomes than conventional approaches for the treatment of infrabony and furcation defects, alveolar ridge preservation, and sinus floor augmentation. Tissue engineering strategies can promote higher root coverage, keratinized tissue width, and gingival thickness gain than scaffolds alone can, and they can often obtain similar mean root coverage compared with autogenous grafts. There is some evidence suggesting that tissue engineering strategies can have a positive effect on patient morbidity, their preference, esthetics, and quality of life when utilized for the treatment of mucogingival deformities. Similarly, tissue engineering strategies can reduce the invasiveness and complications of autogenous graft-based staged bone augmentation. More studies incorporating patient-reported outcomes are needed to understand the cost-benefits of tissue engineering strategies compared with traditional treatments.

A Randomized Clinical Trial Comparing Implants Placed in Two Different Biomaterials Used for Maxillary Sinus Augmentation

The objective of this study was to compare marginal bone loss, surgical and clinical complications, and dental implant survival rate in bilateral maxillary sinus augmented by autologous or porcine xenograft. A randomized controlled clinical trial using split-mouth design enrolled 12 consent adult patients (59.7 ± 8.7 years), who received bilateral maxillary sinus floor augmentation for oral rehabilitation with implant-supported prosthesis. Each patient received both the autologous bone from the mandible (control) or porcine xenograft (test) during the random bilateral sinus lift surgery. A total of 39 dental implants were placed in the posterior maxilla of the 12 patients after 6 months, being rehabilitated after the respective osseointegration period. Both graft materials demonstrated a high implant survival rate at 12 months: 95% for the xenograft side, only 1 implant without osseointegration, and 100% for the autologous side. Radiographic bone loss was low and similar for both groups: control group with a mean of 0.063 ± 0.126, and test group with a mean of 0.092 ± 0.163. No major surgical-related complications have occurred. Only one patient had several prosthetic complications due to fractures of prosthetic components. The maxillary sinus augmentation procedure, both with autologous bone and porcine xenograft materials, is an excellent clinical option procedure for the prosthetic rehabilitation of atrophic maxillae, with low marginal bone loss after one year follow-up, few clinical complications, and a high implant survival rate.

Role of miR-214 in biomaterial transplantation therapy for osteonecrosis

BACKGROUND

The effectiveness and availability of conservative therapies for osteonecrosis of the femoral head (ONFH) are limited. Transplantation of bone marrow mesenchymal stem cells (BMSCs) combined with Bio-Oss, which is a good bone scaffold biomaterial for cell proliferation and differentiation, is a new potential therapy. Of note, the expression of miRNAs was significantly modified in cells cultured with Bio-Oss, and MiR-214 was correlated positively with osteonecrosis. Furthermore, miR-214 was upregulated in cells exposed to Bio-Oss.

OBJECTIVE

To investigate whether targeting miR-214 further improves the transplantation effect.

METHODS

We treated BMSCs with agomiR-214 (a miR-214 agonist), antagomiR-214 (a miR-214 inhibitor), or vehicle, followed by their transplantation into ONFH model rats.

RESULTS

Histological and histomorphometric data showed that bone formation was significantly increased in the experimental groups (Bio-Oss and BMSCs treated with antagomiR-214) compared with other groups.

CONCLUSIONS

miR-214 participates in the inhibition of osteoblastic bone formation, and the inhibition of miR-214 to bone formation during transplantation therapy with Bio-Oss combined with BMSCs for ONFH.

Advances in Tissue Engineering and Implications for Oral and Maxillofacial Reconstruction

BACKGROUND

Reconstructive surgery in the oral and maxillofacial region poses many challenges due to the complexity of the facial skeleton and the presence of composite defects involving soft tissue, bone and nerve defects.

METHODS

Current methods of reconstruction include autologous grafting techniques with local or regional rotational flaps or microvascular free flaps, allografts, xenografts and prosthetic devices.

RESULTS

Tissue engineering therapies utilizing stem cells provide promise for enhancing the current reconstructive options.

CONCLUSIONS

This article is a review on tissue engineering strategies applicable to specialists who treat oral and maxillofacial defects.

PRACTICAL IMPLICATIONS

We review advancements in hard tissue regeneration for dental rehabilitation, soft tissue engineering, nerve regeneration and innovative strategies for reconstruction of major defects.

Implant survival after graftless sinus floor augmentation in highly atrophic maxillae: a randomized controlled trial in a split mouth study

PURPOSE

The success rate of dental implants after graftless sinus augmentation versus conventional sinus augmentation surgery in atrophic maxillae in edentulous patients was investigated.

METHODS

This randomized study was performed in ten edentulous patients with marked maxillary atrophy. On the graftless side, the sinus membrane was lifted by a resorbable membrane. The control side was augmented with a mixture of autografts and xenografts. Implant placement followed 6 months postoperatively. Outcomes were implant survival, success of prosthetic rehabilitation and stability of vertical bone gain.

RESULTS

Ten patients were included. Postoperative radiology showed sufficient bone gain on both maxillary sides. Follow-up varied from 57 to 88 months. The conventional side showed significant (p = 0.041) more bone gain than the experimental side (respectively, 9.69 mm and 6.20 mm). A total of 59 implants were placed: 30 after conventional, 29 after graftless augmentation. One implant was lost on the conventional side and four on the experimental side. The implant survival was significantly higher on the conventional side (96.7% vs. 86.2%, p < 0.001, RR = 4.14). Prosthetic restoration was functionally successful in all cases.

CONCLUSION

Bone gain and implant survival were significantly lower in the non-grafted side versus the grafted side. Prosthetic rehabilitation was possible in all ten patients. The non-grafted technique may have some potential for clinical use, although it showed poorer results. Trial registration The Netherlands Trialregister. NTR NL3541 (NTR3696). Registered 20 January 2013, https://www.trialregister.nl/trial/3541 .

Autogenous Bone and Bioactive Glass around Implants Placed Simultaneously with Ridge Splitting for the Treatment of Horizontal Bony Defects: A Randomised Clinical Trial

Objective

To compare using autogenous bone with or without bioactive glass in ridge splitting of horizontal bone defects combined with simultaneous implant placement.

Materials and Methods

In control group, bone expansion was performed and autogenous bone was used to augment the intercortical bone defect. In study group, autogenous bone was mixed with bioactive glass (1 : 1 in volume). In both groups, the implants were inserted simultaneously with ridge splitting. Six months following implant insertion, bone width and height were evaluated. Statistical analysis utilizing paired Student's t-test was used for comparing results within the same group, whereas independent samples t-test was used for intergroup variables comparison.

Results

The mean bone width and labial and mesiodistal crestal bone height values were increased significantly in both groups from baseline to 6 months postoperatively. Comparing the two groups showed nonstatistical significant difference regarding the labial crestal bone loss, while the ridge width gain values were significantly higher in the study group than in the control group. The mesiodistal bone loss was significantly higher in control group than in study group.

Conclusion

Autogenous bone was mixed with bioactive glass (1 : 1 in volume) to fill intercortical defect created after ridge splitting to decrease peri-implant bone resorption associated with autogenous bone alone. This trial is registered with clinical trial registration: NCT04814160.

Osseointegration of different implant surfaces in areas grafted with deproteinized bovine bone associated or not with fresh bone marrow-Preclinical study in rabbits

OBJECTIVES

To assess the influence of two different implant surfaces on osseointegration in maxillary sinuses of rabbits previously grafted with deproteinized bovine bone (DBB) associated or not with fresh bone marrow (BM).

MATERIAL AND METHODS

Sixteen New Zealand albino rabbits (males, 3.5/4.5 kg and 9-12 months old) were randomly divided into two groups with 8 rabbits each, according to the type of association of biomaterials used to fill the animals' maxillary sinuses: DBB (Deproteinized Bovine Bone) and DBB/BM (Deproteinized bovine bone associated with fresh autologous bone marrow). Ninety (90) days following the grafting procedure, the animals received implants in the area with two different microstructures (SA-Sandblasting + acid attack and SA-H-Sandblasting + acid attack + immersion in 0.9% sodium chloride isotonic solution). All rabbits were euthanized 90 days after implant placement. The microtomographic analysis was performed to verify the number of mineralized tissues around the implants throughout their length (%BV/TV), while the histomorphometric analysis was performed to verify the percentage of bone-implant contact around the implants throughout their length (%BIC).

RESULTS

We observed no differences in the quantity for %BV/TV (DBB-SA:33.25 ± 19.67; DBB-SA-H:35.15 ± 22.17; DBB/BM-SA:39.71 ± 24.21; DBB/BM-SA-H:36.40 ± 23.07) and %BIC (DBB-SA:58.94 ± 24.37; DBB-SA-H:52.52 ± 24.36; DBB/BM-SA: 61.66 ± 14.60; DBB/BM-SA-H: 64.06 ± 23.30) between the groups assessed.

CONCLUSIONS

The addition of BM and the type of surface did not influence the osseointegration of implants installed in areas grafted with sintered deproteinized bovine bone at high temperatures in the late period assessed.

Comparison of concentrated fresh mononuclear cells and cultured mesenchymal stem cells from bone marrow for bone regeneration

Autologous bone marrow mononuclear cell (BMMNC) transplantation has been widely studied in recent years. The fresh cell cocktail in BMMNCs, without going through the in vitro culture process, helps to establish a stable microenvironment for osteogenesis, and each cell type may play a unique role in bone regeneration. Our study compared the efficacy of concentrated fresh BMMNCs and cultured bone marrow‐derived mesenchymal stem cells (BMSCs) in Beagle dogs for the first time. Fifteen‐millimeter segmental bone defects were created in the animals' tibia bones. In BMMNCs group, the defects were repaired with concentrated fresh BMMNCs combined with β‐TCP (n = 5); in cultured BMSC group, with in vitro cultured and osteo‐induced BMSCs combined with β‐TCP (n = 5); in scaffold‐only group, with a β‐TCP graft alone (n = 5); and in blank group, nothing was grafted (n = 3). The healing process was monitored by X‐rays and single photon emission computed tomography. The animals were sacrificed 12 months after surgery and their tibias were harvested and analyzed by microcomputed tomography and hard tissue histology. Moreover, the microstructure, chemical components, and microbiomechanical properties of the regenerated bone tissue were explored by multiphoton microscopy, Raman spectroscopy and nanoindentation. The results showed that BMMNCs group promoted much more bone regeneration than cultured BMSC group. The grafts in BMMNCs group were better mineralized, and they had collagen arrangement and microbiomechanical properties similar to the contralateral native tibia bone. These results indicate that concentrated fresh bone marrow mononuclear cells may be superior to in vitro expanded stem cells in segmental bone defect repair.

Maxillary sinus lift response to platelet-rich plasma associated with autogenous bone, ceramic biphasic HA/β-TCP (70:30), or deproteinized bovine bone

BACKGROUND

This study evaluated the long-term effects of platelet-rich plasma (PRP) on bone formation and regeneration when associated with autogenous bone graft (AB), porous biphasic calcium phosphate (pBCP), or deproteinized bovine bone (DBB) in maxillary sinus augmentation (MSA) of rabbit.

METHODS

In 54 rabbits, bilateral MSA procedure was performed and randomly one sinus was filled with 200 mm³ material plus blood clot (AB/clot, DBB/clot, and pBCP/clot) and other with the same graft plus PRP (AB/PRP, DBB/PRP, and pBCP/PRP). After 30, 60, and 180 days, microtomographic were performed to analyze the three-dimensional MSA volume and histomorphometric analyses for the percentage of bone and soft tissues ingrowth. Data were compared by two-way ANOVA and the means were compared by the Tukey test, at p < 0.05.

RESULTS

The percentage of pBCP and DBB were nearly unchanged throughout the whole period and bone formation occurred in the spaces between particles. The MSA volume filled with DBB and pBCP agglutinated with clot and PRP maintained constant during all experimental periods (147.2 mm³ and 154.9 mm³, respectively, p = 0.7377), and no significant changes in the new formatted bone and soft tissue were observed between treatments. In AB/clot and AB/PRP, the MSA volume was similar at 30 days (140.3 mm³ and 137.9 mm³, respectively), but a higher and gradual reduction was observed until 180 days. In the AB/PRP, this reduction was significantly higher (44.2%) than AB/clot (22.5%) (p = 0.01792). Histologically, the addition of PRP to AB accelerated the new bone formation/remodeling maintaining the percentage of new bone similar to AB/clot during all experimental volume (p = 0.6406), while the AB particles showed a higher resorption in AB/PRP than AB/clot until 60 days (mean of 7.8% and 15.1%, respectively, p = 0.0396).

CONCLUSION

The association of PRP with the autogenous graft accelerates the process of bone formation/remodeling in MSA, but not had influence on the pBCP and DBB groups.

Efficacy of autologous stem cells for bone regeneration during endosseous dental implants insertion - A systematic review of human studies

Availability of adequate quantity and quality of bone is prerequisite for longevity and survival of endosseous dental implants. Most of the clinicians face with the problem of lack of bone due to long-standing edentulism during this treatment modality. Conventional therapies with the use of various types of bone grafts and membranes have provided clinicians with unpredictable and compromised results. Cell-based therapies utilizing undifferentiated cells, that have the potential to differentiate into various cell types including osteoblastic lineages, have demonstrated through various previously conducted in-vitro and animal studies, a successful formation of bone in a predictable manner. Thus the main objective of this review was to evaluate the effectiveness of these therapies when applied on human subjects. A search was carried out in MEDLINE (via PubMed) and Cochrane CENTRAL databases for completed randomized and non-randomised clinical trials utilizing stem cell-based therapies with histologic and radiographic analysis written in English up to January 2019. This search of the literature yielded 10 studies meeting the inclusion and exclusion criteria. In all these studies, stem cells were primarily used to achieve bone augmentation during insertion of endosseous dental implants. Results of these therapies conducted on human subjects have shown a positive impact on bone regeneration, in particular, therapies utilizing bone marrow and adipose tissue derived stem cells. But the clinicians need to examine the efficacy, safety, feasibility of these therapies while treating large size defects or planning for shorter healing period and early loading of dental implants.

Full Regeneration of Maxillary Alveolar Bone Using Autogenous Partially Demineralized Dentin Matrix and Particulate Cancellous Bone and Marrow for Implant-Supported Full Arch Rehabilitation

Autogenous partially demineralized dentin matrix (APDDM) has been reportedly used as a superior bone graft material. A 52-year-old Japanese man who exhibited severe periodontitis was referred for oral rehabilitation. He underwent wide-range anterior maxillary alveolar bone and bilateral sinus floor augmentation by grafting of a mixture of APDDM and particulate cancellous bone and marrow (PCBM); subsequently, he underwent implant-supported full arch rehabilitation. He has been followed up for 4 years after placement of the final restoration without any complications, and his physiological bone volume has been maintained. APDDM constitutes an alternative treatment that may increase the volume of graft material and might prevent rapid resorption of PCBM, because APDDM served as a scaffold for osteoblasts from PCBM. When possible, it may be useful to apply APDDM as a graft material with PCBM for large-volume alveolar bone regeneration.

Local effect of simvastatin combined with different osteoconductive biomaterials and collagen sponge on new bone formation in critical defects in rat calvaria

Purpose

To evaluate the local effect of simvastatin (SVT) combined with deproteinized bovine bone (DBB) with hydroxyapatite/β-tricalcium phosphate biphasic ceramics (HA/TCP) and with collagen sponge (CS) on bone repair in critical size defects (CSDs) in rat calvaria.

Methods

Forty-two 5-mm diameter CSDs were made bilaterally in the calvaria of 18 rats. The animals were allocated according to the type of biomaterial and associations used to fill the CSD. After 8 weeks, the animals were euthanized, and their calvaria were evaluated for repaired tissue composition using histologic and histometric analyses.

Results

In the histometric analysis, the use of SVT showed to increase bone formation in the CSDs when combined with all the bone substitutes tested in this study (p<0.05). Greater bone formation was observed in the groups with SVT compared to the groups without SVT.

Conclusions

The use of SVT without the need for a vehicle and combined with a commercially available biomaterial may be a cheaper way to potentiate the formation of bone tissue without the need to produce new biomaterials. Therefore, SVT combined with DBB induced significantly greater new bone formation than did the other treatments.

Efficacy of stem cells in maxillary sinus floor augmentation: systematic review and meta-analysis

The aim of this review was to test the hypothesis of no difference in the efficacy of bone regeneration when using stem cells in maxillary sinus floor augmentation surgery in comparison to other grafts. Nine randomized clinical trials and one follow-up study involving human subjects were identified through a search of the PubMed/MEDLINE, Scopus, Cochrane, and Web of Science databases, supplemented by a hand search. No significant difference between groups was found for the implant survival rate, increase in bone height, marginal bone loss following implant placement, or new bone formation. With regard to the residual bone graft, an effect favouring the graft group at 3-4months (P=0.001) and favouring the stem cell group at 6months (P=0.01) was found. Analyses of the subgroup in which the BMAC system extraction method was used in combination with Bio-Oss, revealed no difference in new bone formation; however, the results for residual bone graft at 3months favoured the control graft (Bio-Oss) (P=0.01), but at 6months favoured the stem cells (Bio-Oss+BMAC system) (P=0.01). Based on all findings, the use of stem cells does not contribute significantly to greater implant survival rates or the efficacy of bone regeneration following sinus lift procedures.

Bone, Periodontal and Dental Pulp Regeneration in Dentistry: A Systematic Scoping Review

The aim of presented systematic scoping review was to investigate the actual and future clinical possibilities of regenerative therapies and their ability to regenerate bone, periodontal and pulp with histological confirmation of the nature of formed tissue. Electronic search was conducted using a combination between Keywords and MeSH terms in PubMed, Scopus, ISI-Web of Science and Cochrane library databases up to January 2016. Two reviewers conducted independently the papers judgment. Screened studies were read following the predetermined inclusion criteria. The included studies were evaluated in accordance with Arksey and O'Malley's modified framework. From 1349 papers, 168 completed inclusion criteria. Several characterized and uncharacterized cells used in Cell Therapy have provided bone regeneration, demonstrating bone gain in quantity and quality, even as accelerators for bone and periodontal regeneration. Synthetic and natural scaffolds presented good cell maintenance, however polyglycolid-polylactid presented faster resorption and consequently poor bone gain. The Growth Factor-Mediated Therapy was able to regenerate bone and all features of a periodontal tissue in bone defects. Teeth submitted to Revascularization presented an increase of length and width of root canal. However, formed tissues not seem able to deposit dentin, characterizing a repaired tissue. Both PRP and PRF presented benefits when applied in regenerative therapies as natural scaffolds. Therefore, most studies that applied regenerative therapies have provided promising results being possible to regenerate bone and periodontal tissue with histological confirmation. However, pulp regeneration was not reported. These results should be interpreted with caution due to the short follow-up periods.

Does intraoperative perforation of Schneiderian membrane during sinus lift surgery causes an increased the risk of implants failure?: A systematic review and meta regression analysis

PURPOSE

There is still debate whether intraoperative Schneiderian membrane (SM) perforation in the maxillary sinus lift causes an increase the risk of implants failure. The aim of this study was to assess an association between SM perforation and implants loss following the maxillary sinus lift.

MATERIALS AND METHODS

A systematic review and meta-analysis of clinical studies assessing association between SM perforation and implants failure based on PRISMA was conducted. Three major databases were used to gather research dating from their respective inception up until March 2018. All clinical studies expressly reported the number of the SM perforation and implants loss that installed in the perforated and nonperforated sinuses were included. The statistical analyses used were Pearson's correlation, simple linear regression, and meta regression. The risk ratio (RR) of implant loss between perforated and nonperforated sites was estimated.

RESULTS

A total of 2947 patients with 3884 maxillary sinuses augmentations who received 7358 implants, enrolled in 58 studies were included in this study. There was a significant relationship between the implants' failure and SM perforation according to simple linear regression (P < .001) and meta regression analysis (P = .06). There was a significant decrease (moderate quality evidence) in implant loss in the nonperforated sinuses compared to perforated sunrises (RR = 2.17, CI: 1.52-3.10, P = .001). There was also no significant association between implant loss in the perforated sinuses and the surgical devices used (piezosurgical or rotary), surgical approach applied (lateral or crestal sinus lift), barrier membrane used and type of bone grafting materials.

CONCLUSION

The results of this study showed that an intraoperative SM perforation could increase the risk of implant failure after the sinus lift surgery.

Sinus Floor Augmentation With Ambient Blood and an Absorbable Collagen Sponge: A Prospective Pilot Clinical Study

PURPOSE

The aim of this study was to clinically, radiologically, and histologically evaluate a sinus augmentation technique using a resorbable collagen sponge to maintain space between the Schneiderian membrane and the residual crestal bone.

MATERIALS AND METHODS

Patients with partially edentulous maxillae were clinically and radiographically evaluated for implant placement. A total of 10 consecutive patients with the bone height for implant placement (<4.0 mm) were enrolled in the study. The lateral maxillary wall was surgically exposed and the Schneiderian membrane was carefully elevated. A collagen wound dressing was placed in the antral area between the sinus floor and the raised membrane. The vertical sinus floor height was calculated using cone-beam computed tomography before the surgical procedure (baseline) and at 6 months postoperative. Immediately after the second scan, a core biopsy was removed for histological evaluation. The biopsy site was then further prepared for implant placement in the same location.

RESULTS

Biopsies showed mature cancellous bone with a predominantly lamellar structure. Well-vascularized intertrabecular spaces were filled with connective tissue and bone marrow. Analysis of bone height changes showed significant mean (SD) differences before and after procedures in anterior (2.67 ± 0.62 mm and 11.15 ± 1.1 mm), medial (2.98 ± 0.55 mm and 10.96 ± 0.77 mm), and posterior (3.17 ± 0.91 mm and 10.63 ± 0.51 mm) maxillary jaw locations (P = 0.005).

CONCLUSION

The collagen sponge provided an effective substrate for osseous regeneration of the sinus floor.

Bioactive glass added to autogenous bone graft in maxillary sinus augmentation: a prospective histomorphometric, immunohistochemical, and bone graft resorption assessment

Objective

The aim of this study was to compare the bone resorption rate, histomorphometry and immunohistochemical findings of bioactive glass (Biogran; Biomet, Warsaw, IN, USA) mixed with autogenous bone grafts (1:1) and autogenous bone graft isolate in maxillary sinus elevation surgery.

Material and Methods

A total of 9 maxillary sinuses were grafted with Biogran with autogenous bone graft (group 1) and 12 were mixed with autogenous bone graft (group 2). Postoperative cone beam computed tomography (CBCT) was used to measure the initial graft volume after 15 days (T1), and 6 months later, another CBCT scan was performed to evaluate the final graft volume (T2) and determine the graft resorption rate. The resorption outcomes were 37.9%±18.9% in group 1 and 45.7%±18.5% in group 2 (P=0.82). After 6 months, biopsies were obtained concurrent with the placement of dental implants; these implants were subjected to histomorphometric analysis and immunohistochemical analysis for tartrate-resistant acid phosphatase (TRAP).

Results

The average bone formation in group 1 was 36.6%±12.9 in the pristine bone region, 33.2%±13.3 in the intermediate region, and 45.8%±13.8 in the apical region; in group 2, the values were 34.4%±14.4, 35.0%±13.9, and 42.0%±16.6 of new bone formation in the pristine bone, intermediate, and apical regions, respectively. Immunostaining for TRAP showed poor clastic activity in both groups, which can indicate that those were in the remodeling phase.

Conclusions

The similarity between the groups in the formation and maintenance of the graft volume after 6 months suggests that the bioactive glass mixed with autogenous bone (1:1) can be used safely as a bone substitute for the maxillary sinus lift.

Applications of Mesenchymal Stem Cells in Sinus Lift Augmentation as a Dental Implant Technology

The potential application of stem cell biology in human dentistry is a new and emerging field of research. The objective of the current review was to study the efficiency of mesenchymal stem cells (MSCs) in sinus lift augmentation (SLA). A literature review was performed in PubMed Central using MeSH keywords such as sinus lift, MSCs, dental implants, and augmentation. The searches involved full-text papers written in English, published in the past 10 years (2007–2017). The review included in vitro and in vivo studies on the use of MSCs in SLA. Electronic searching provided 45 titles, and among them, 8 papers were chosen as suitable based on the inclusion requirements of this review. The reviewed studies have revealed the potential of MSCs in SLA. According to these papers, stem cell therapy combined with different biomaterials may considerably improve bone regeneration in previous steps of dental implantation and may veritably lead to efficient clinical usages in the recent future. However, the identification of an ideal source of stem cells as well as long-term studies is vital to assess the success rate of this technology. Further clinical trials are also needed to approve the potential of MSCs in SLA.

Comparative study of volumetric changes and trabecular microarchitecture in human maxillary sinus bone augmentation with bioactive glass and autogenous bone graft: a prospective and randomized assessment

The aim of this study was to compare the volumetric changes and the new bone microarchitecture in human maxillary sinuses augmented with bioactive glass (Biogran) alone, bioactive glass combined with autogenous bone graft (1:1), or autogenous bone graft alone. Twelve maxillary sinuses were grafted with bioactive glass (group 1), nine with bioactive glass mixed with autogenous bone graft 1:1 (group 2), and 12 with autogenous bone graft (group 3). Patients underwent cone beam computed tomography 15days after the procedure to determine the initial volume of the graft (T1) and again 6 months later (T2). Biopsies were obtained at the time of dental implant placement and were subjected to micro-computed tomography. The volumetric change was 44.2% in group 1, 37.9% in group 2, and 45.7% in group 3 (P>0.05). The trabecular microarchitecture results showed that the materials used in groups 1 and 2 were good bone substitutes. However, the addition of 50% bioactive glass to autogenous bone graft improved the microarchitecture of the graft. Furthermore, the results for volumetric changes indicated that bioactive glass, its association with autogenous bone graft in a 1:1 ratio, and autogenous bone graft alone have similar resorption.

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

BACKGROUND

Few studies have been conducted to assess new bone formation using Biogran, a bioactive glass, in maxillary sinus bone augmentation through a prospective and randomized 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.

MATERIALS 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, samples 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.

Three-dimensional cone beam computed tomography analysis of maxillary sinus and alveolar bone anatomy in the restorative axis of dental implants using radiopaque drill guides

The objectives were to assess the sinus anatomy and alveolar ridge dimensions and to identify clinical factors and morphological relationships that may predict the characteristics of the sinus anatomy. A total 336 edentulous molar and 168 edentulous premolar regions were analyzed. The mediolateral maxillary sinus (5mm and 10mm above alveolar bone), lateral maxillary sinus wall, ostium height, and alveolar ridges were measured. Measurement regions were defined by radiopaque simulation of the restoration goal. Mean molar mediolateral dimensions were >10mm: first molar, 11.8mm (range 3.8-21.1mm); second molar, 12.2mm (range 7.9-20.1mm). The extent of the sinus differed significantly between premolars and molars (P<0.001). The first molar region had the highest mean value for the lateral sinus wall (2.4mm, range 0.2-7.9mm) and the greatest distance between the alveolar crest and simulated restorative goal (8.1mm, range 1.1-16.3mm). Septum prevalence was 46% in the molar region and 27% in the premolar region. A lower alveolar ridge height was associated with a wider transverse extent of maxillary sinus and consequently longer distances between the crest and restorative goal. Systematic three-dimensional analysis of the maxillary sinus yields precise preoperative information about sinus configurations. There were significant variations and relationships among characteristics of the maxillary sinus, ridge, and the restorative goal.

Maxillary sinus grafting with fresh frozen allograft versus bovine bone mineral: A tomographic and histological study

We evaluated histologically and tomographically the effects of fresh frozen bone allograft (FFB) or bovine bone mineral (BBM) in maxillary sinus floor augmentations. In total, 30 maxillary sinuses from 30 patients (mean age = 51.17 ± 10.86 years) underwent sinus augmentation. Patients were divided in two test groups (15 sinuses each). The first group was grafted with allograft bone, and the second group received bovine bone mineral. After 6 months, bone samples from each group were collected for histological examination. Implant survival rates were 97.78% (FFB group) and 100% (BBM group) 6 months after functional loading. Median volumetric reductions of 31.2% (11.33-40.56) and 12.22% (9.91-20.59) were observed in the FFB and BBM groups, respectively. Comparisons between the groups for differences in initial and final volumes of bone (p = 0.015) and the rate of resorption (p = 0.009) showed statistically significant differences. The FFB group showed osteoblastic cells in close contact with osteoid matrix, connected through bridges between allograft bone particles and new bone formation. The BBM group showed BBM particles in close contact with new bone, with visible osteoid matrix bridges and osteoblastic cells surrounding it. None showed signs of acute or chronic inflammatory infiltrate. Despite better results with BBM, both FFB and BBM in maxillary sinus augmentation resulted in high percentages of new bone formation, and allowed implant placement with a low rate of failure of osseointegration at a 6-month follow-up.

Advancing biomaterials of human origin for tissue engineering

Biomaterials have played an increasingly prominent role in the success of biomedical devices and in the development of tissue engineering, which seeks to unlock the regenerative potential innate to human tissues/organs in a state of deterioration and to restore or reestablish normal bodily function. Advances in our understanding of regenerative biomaterials and their roles in new tissue formation can potentially open a new frontier in the fast-growing field of regenerative medicine. Taking inspiration from the role and multi-component construction of native extracellular matrices (ECMs) for cell accommodation, the synthetic biomaterials produced today routinely incorporate biologically active components to define an artificial in vivo milieu with complex and dynamic interactions that foster and regulate stem cells, similar to the events occurring in a natural cellular microenvironment. The range and degree of biomaterial sophistication have also dramatically increased as more knowledge has accumulated through materials science, matrix biology and tissue engineering. However, achieving clinical translation and commercial success requires regenerative biomaterials to be not only efficacious and safe but also cost-effective and convenient for use and production. Utilizing biomaterials of human origin as building blocks for therapeutic purposes has provided a facilitated approach that closely mimics the critical aspects of natural tissue with regard to its physical and chemical properties for the orchestration of wound healing and tissue regeneration. In addition to directly using tissue transfers and transplants for repair, new applications of human-derived biomaterials are now focusing on the use of naturally occurring biomacromolecules, decellularized ECM scaffolds and autologous preparations rich in growth factors/non-expanded stem cells to either target acceleration/magnification of the body's own repair capacity or use nature's paradigms to create new tissues for restoration. In particular, there is increasing interest in separating ECMs into simplified functional domains and/or biopolymeric assemblies so that these components/constituents can be discretely exploited and manipulated for the production of bioscaffolds and new biomimetic biomaterials. Here, following an overview of tissue auto-/allo-transplantation, we discuss the recent trends and advances as well as the challenges and future directions in the evolution and application of human-derived biomaterials for reconstructive surgery and tissue engineering. In particular, we focus on an exploration of the structural, mechanical, biochemical and biological information present in native human tissue for bioengineering applications and to provide inspiration for the design of future biomaterials.

Maxillary sinus floor augmentation and dental implant placement using dentin matrix protein-1 gene-modified bone marrow stromal cells mixed with deproteinized boving bone: A comparative study in beagles

OBJECTIVE

The aim of the study was to evaluate the effects of the combined use of dentin matrix protein-1 (DMP1) gene-modified bone marrow stromal cells (BMSCs) and Bio-Oss(®) for maxillary sinus floor augmentation (MSFA) implant placement in dogs.

MATERIALS AND METHODS

BMSCs were derived from bone marrow of six beagles and cultured. The cells were transduced with a lentiviral vector overexpressing the DMP1 gene and enhanced green fluorescent protein (EGFP) gene (Lenti-DMP1/EGFP) in test group, and with a lentiviral vector encoding EGFP gene (Lenti-EGFP) in control group. Six dogs received sinus augmentations using the bilateral approach with a simultaneous implant placement at each site respectively. At the same concentration, 2×10(7) cells/ml, one sinus was grafted using a mixture of autologous DMP1/EGFP gene-modified BMSCs and Bio-Oss(®) (DMP1 group), and the contralateral sinus was grafted with autologous EGFP gene-modified bMSCs and Bio-Oss(®) (EGFP group). After a 3 month healing period, bone regeneration and osseointegration were evaluated using histologic and histomorphometric methods.

RESULTS

The bone-implant contact (BIC) and the bone area fraction in the DMP1 group (BIC: 34.67%±8.23%, bone area fraction: 35.16%±3.32%) were significantly greater compared with the EGFP group (BIC: 26.06%±5.16%, bone area fraction: 20.74%±1.63%) (P<0.05). No significant difference between the residual bone substitute material volume (BSMV) in the DMP1 group (35.86±7.35) and the EGFP group (32.16±9.16) was found in our study (P>0.05).

CONCLUSION

BMSCs modified with the DMP1 gene can be used as an adjunct to Bio-Oss(®) to enhance new bone formation and the osseointegration of dental implants in MSFA of dogs.

Effects of platelet-rich plasma in association with bone grafts in maxillary sinus augmentation: a systematic review and meta-analysis

This systematic review evaluated the effect on bone formation and implant survival of combining platelet-rich plasma (PRP) with bone grafts in maxillary augmentation. A comprehensive review of articles listed in the PubMed/MEDLINE, Embase, and Cochrane Library databases covering the period January 2000 to January 2015 was performed. The meta-analysis was based on bone formation for which the mean difference (MD, in millimetres) was calculated. Implant survival was assessed as a dichotomous outcome and evaluated using the risk ratio (RR) with 95% confidence interval (CI). The search identified 3303 references. After inclusion and exclusion criteria were applied, 17 studies were selected for qualitative analysis and 13 for quantitative analysis. A total of 369 patients (mean age 51.67 years) and 621 maxillary sinus augmentations were evaluated. After the data analysis, additional analyses were performed of the implant stability quotient, marginal bone loss, and alveolar bone height measured by MD. The results showed no significant difference in implant stability (P=0.32, MD 1.00, 95% CI -0.98 to 2.98), marginal bone loss (P=0.31, MD 0.06, 95% CI -0.05 to 0.16), alveolar bone height (P=0.10, MD -0.72, 95% CI -1.59 to 0.14), implant survival (P=0.22, RR 1.95, 95% CI 0.67-5.69), or bone formation (P=0.81, MD -0.63, 95% CI -5.91 to 4.65). In conclusion, the meta-analysis indicates no influence of PRP with bone graft on bone formation and implant survival in maxillary sinus augmentation.

Endothelial Progenitor Cell Fraction Contained in Bone Marrow-Derived Mesenchymal Stem Cell Populations Impairs Osteogenic Differentiation

In bone tissue engineering (TE) endothelial cell-osteoblast cocultures are known to induce synergies of cell differentiation and activity. Bone marrow mononucleated cells (BMCs) are a rich source of mesenchymal stem cells (MSCs) able to develop an osteogenic phenotype. Endothelial progenitor cells (EPCs) are also present within BMC. In this study we investigate the effect of EPCs present in the BMC population on MSCs osteogenic differentiation. Human BMCs were isolated and separated into two populations. The MSC population was selected through plastic adhesion capacity. EPCs (CD34⁺ and CD133⁺) were removed from the BMC population and the resulting population was named depleted MSCs. Both populations were cultured over 28 days in osteogenic medium (Dex⁺) or medium containing platelet lysate (PL). MSC population grew faster than depleted MSCs in both media, and PL containing medium accelerated the proliferation for both populations. Cell differentiation was much higher in Dex⁺ medium in both cases. Real-time RT-PCR revealed upregulation of osteogenic marker genes in depleted MSCs. Higher values of ALP activity and matrix mineralization analyses confirmed these results. Our study advocates that absence of EPCs in the MSC population enables higher osteogenic gene expression and matrix mineralization and therefore may lead to advanced bone neoformation necessary for TE constructs.

Mesenchymal stem cells in maxillary sinus augmentation: A systematic review with meta-analysis

AIM: To investigate the effectiveness of mesenchymal stem cells (MSCs) in maxillary sinus augmentation (MSA), with various scaffold materials.

METHODS: MEDLINE, EMBASE and SCOPUS were searched using keywords such as sinus graft, MSA, maxillary sinus lift, sinus floor elevation, MSC and cell-based, in different combinations. The searches included full text articles written in English, published over a 10-year period (2004-2014). Inclusion criteria were clinical/radiographic and histologic/ histomorphometric studies in humans and animals, on the use of MSCs in MSA. Meta-analysis was performed only for experimental studies (randomized controlled trials and controlled trials) involving MSA, with an outcome measurement of histologic evaluation with histomorphometric analysis reported. Mean and standard deviation values of newly formed bone from each study were used, and weighted mean values were assessed to account for the difference in the number of subjects among the different studies. To compare the results between the test and the control groups, the differences of regenerated bone in mean and 95% confidence intervals were calculated.

RESULTS: Thirty-nine studies (18 animal studies and 21 human studies) published over a 10-year period (between 2004 and 2014) were considered to be eligible for inclusion in the present literature review. These studies demonstrated considerable variation with respect to study type, study design, follow-up, and results. Meta-analysis was performed on 9 studies (7 animal studies and 2 human studies). The weighted mean difference estimate from a random-effect model was 9.5% (95%CI: 3.6%-15.4%), suggesting a positive effect of stem cells on bone regeneration. Heterogeneity was measured by the I² index. The formal test confirmed the presence of substantial heterogeneity (I² = 83%, P < 0.0001). In attempt to explain the substantial heterogeneity observed, we considered a meta-regression model with publication year, support type (animal vs humans) and follow-up length (8 or 12 wk) as covariates. After adding publication year, support type and follow-up length to the meta-regression model, heterogeneity was no longer significant (I² = 33%, P = 0.25).

CONCLUSION: Several studies have demonstrated the potential for cell-based approaches in MSA; further clinical trials are needed to confirm these results.

Characterization and cytocompatibility of a new injectable multiphasic bone substitute based on a combination of polysaccharide gel-coated OSPROLIFE(®) HA/TTCP granules and bone marrow concentrate

The purpose of this study was to examine the in vitro cytocompatibility of a novel injectable multiphasic bone substitute (MBS) based on polysaccharide gel-coated OSPROLIFE(®) hydroxyapatite (HA)/tetracalcium phosphate (TTCP) granules combined with bone marrow concentrate (BMC). Polysaccharide gel-coated granules loaded in syringe were combined with BMC diluted in ionic crosslinking solution. The product was then maintained in culture to investigate the cytocompatibility, distribution, and osteogenic differentiation function of cells contained in the BMC. The in vitro cytocompatibility was assessed after 0, 24, and 96 h from the injectable MBS preparation using the LIVE/DEAD(®) staining kit. The results highlighted that cells remained viable after combination with the polysaccharide gel-coated granules; also, viability was maintained over time. The distribution of the cells in the product, observed using confocal microscopy, showed viable cells immersed in the polysaccharide gel formed between the granules after ionic crosslinking. The mesenchymal stromal cells (MSC) contained in the injectable MBS, the basic elements for bone tissue regeneration, were able to differentiate toward osteoblasts, producing an osteogenic matrix as evidenced by alizarin red-s (AR-S) staining. In conclusion, we found that the injectable MBS may have the potential to be used as a bone substitute by applying a "one-step" procedure in bone tissue engineering applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 894-902, 2016.

Fresh-frozen allografts combined with bovine bone mineral enhance bone formation in sinus augmentation

We evaluated histologically, histomorphometrically, and tomographically the effects of the association of fresh-frozen bone allograft (FFB) with bovine bone mineral (BBM) in maxillary sinus floor augmentation. In total, 34 maxillary sinuses from 29 patients, with a mean age of 51.32 (±6.44) years, underwent sinus augmentation. Patients were divided into control and test groups (17 sinuses each). The controls were grafted with allograft bone, and the test group received a combination of FFB and BBM at a 2:1 ratio. After 6 months, bone samples were collected for histological and histomorphometric examinations. The implant survival rates were 93.02% (control group) and 100% (test group) at 6 months after functional loading. Median volumetric reductions of 28.32% (17.05-44.05) and 12.62% (5.65-16.87) were observed for the control and test groups, respectively. Statistically significant histomorphometric differences were found between the control and test groups regarding newly formed bone 12.54% (10.50-13.33) vs. 24.42% (17.62-35.92), p < 0.001, total bone 48.34% (39.03-54.42) vs. 61.32% (50.61-64.96), p = 0.007, and connective tissue 51.66% (45.57-60.97) vs. 39.30% (35.03-49.37), p = 0.007. The addition of BBM to allograft bone in maxillary sinus augmentation resulted in higher percentages of new bone formation and total bone, and permitted implant placement with a low rate of osseointegration failure at the 6-month follow-up.

Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus

BACKGROUND

Insufficient bone volume is a common problem encountered in the rehabilitation of the edentulous posterior maxillae with implant-supported prostheses. Bone volume is limited by the presence of the maxillary sinus together with loss of alveolar bone height. Sinus lift procedures increase bone volume by augmenting the sinus cavity with autogenous bone or commercially available biomaterials, or both. This is an update of a Cochrane review first published in 2010.

OBJECTIVES

To assess the beneficial or harmful effects of bone augmentation compared to no augmentation when undertaking a sinus lift procedure. Secondly, to compare the benefits and harms of different maxillary sinus lift techniques for dental implant rehabilitation.

SEARCH METHODS

We searched the Cochrane Oral Health Group's Trials Register (to 17 January 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 12), MEDLINE via OVID (1946 to 17 January 2014) and EMBASE via OVID (1980 to 17 January 2014). There were no language or date restrictions on the searches of the electronic databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of different techniques and materials for augmenting the maxillary sinus for rehabilitation with dental implants that report the outcome of implant success or failure at least to four months after initial loading.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, assessment of the risk of bias of the trials, and data extraction were conducted independently and in duplicate. Authors were contacted for any missing information. Results were expressed using fixed-effect models as there were either less than four studies or we used Peto odds ratios (ORs) for dichotomous data when there were zero cells in either the treatment or control or both arms and the number of trials was small. The statistical unit of the analysis was the patient.

MAIN RESULTS

Eighteen RCTs out of 64 potentially eligible study reports met the inclusion criteria. They compared undertaking a sinus lift with not doing so, and the use of different sinus lift techniques. There were 650 patients providing data for the outcomes evaluated. Five studies were assessed as low risk of bias, 11 were assessed as high risk of bias, and in two the risk was unclear. Sinus lift versus no sinus lift Four trials of moderate quality (three trials at low and one at high risk of bias) with 102 participants evaluated short implants (5 to 8.5 mm long) as an alternative to sinus lift in bone with residual height between 4 and 9 mm. One year after loading there was insufficient evidence to claim differences between the two procedures for prosthesis failure (OR (Peto) 0.37, 95% confidence interval (CI) 0.05 to 2.68; three trials) or implant failure (OR (Peto) 0.44, 95% CI 0.10 to 1.99; four trials). There was however an increase in complications at treated sites when undertaking the sinus lift (OR (Peto) 4.77, 95% CI 1.79 to 12.71, P value = 0.002; four trials). Different sinus lift techniques Fourteen trials with 548 participants compared different sinus lift techniques. Only three comparisons included more than one trial (two trials for each). These were bone graft versus no bone graft, autogenous bone versus bone substitute, bone graft with or without platelet-rich plasma (PRP). There was insufficient evidence to claim a benefit for any of these techniques for the primary outcomes of prosthesis and implant failure. For the other reported outcomes, in a single study at high risk of bias, only bone gain was greater for the bone graft site than the site without a graft six months after augmentation, however this was not significant at 18 or 30 months.The other comparisons with single studies were rotary versus piezosurgery to open a lateral sinus window, two different bone substitutes, use or not of a membrane to seal the lateral window, one- versus two-stage lateral sinus lift, two-stage granular bone versus one-stage autogenous bone blocks, and crestal versus lateral sinus lift; two trials compared three different crestal sinus lifting techniques: rotatory versus hand malleting (patients preferred rotatory instruments over hand malleting) and hand versus electric malleting. There was no evidence of a benefit for any sinus lift procedure compared to any other for the primary outcomes prosthesis or implant failure.

AUTHORS' CONCLUSIONS

There is moderate quality evidence which is insufficient to determine whether sinus lift procedures in bone with residual height between 4 and 9 mm are more or less successful than placing short implants (5 to 8.5 mm) in reducing prosthesis or implant failure up to one year after loading. However, there are more complications at sites treated with sinus lift procedures. Many trials compared different sinus lift procedures and none of these indicated that one procedure reduced prosthetic or implant failures when compared to the other. Based on low quality evidence, patients may prefer rotary instruments over hand malleting for crestal sinus lift.

Follow-up of implant survival comparing ficoll and bone marrow aspirate concentrate methods for hard tissue regeneration with mesenchymal stem cells in humans

Objective: Clinical follow-up of implant survival in 11 patients comparing two different methods for mesenchymal stem cell (MSC) isolation (Ficoll and bone marrow aspirate concentrate [BMAC]) applied in maxillary sinus augmentation.

Methods: Mononuclear cells, including MSCs, were concentrated with either Ficoll (control group, n=6 sinus) or BMAC (test group, n=12 sinus) and transplanted in combination with bovine bone mineral. A total of 50 implants were placed in a second surgical intervention (17 Ficoll/33 BMAC) and loaded after 4 months. Overall implant survival was assessed with a Kaplan-Meier model using package survival under R.

Results: Implant survival of the Ficoll group was 100% compared with the BMAC group, which had 93.4% survival (95% confidence interval, 0.849–1). The difference between the groups was not significant (p=0.381).

Conclusion: The BMAC system is an effective and suitable “chair-side” method for clinical application in hard tissue regeneration.