Maxillary Sinus Floor Augmentation Research Articles

Clinical and Radiographic Evaluation of Modified Transalveolar Two-Step Osteotome-Mediated Localized Maxillary Sinus Elevation: A Retrospective Computed Tomography Study with a 3-Year Follow-up.

This study aimed to report a practicable and noninvasive two-stage technique for sinus elevation and delayed implant insertion in the augmented site with residual bone height down to 3 mm or even lower. The surgical technique employed a two-stage process for rehabilitation of posterior maxillary single-tooth edentulous areas, involving, in the first step, transcrestal maxillary sinus floor augmentation with a collagen sponge to fill the intrabony cavity resulting from the detachment of the sinus membrane; the second step consisted of another indirect sinus floor elevation using magnetoelectric surgery with immediate implant placement and no grafting material. Changes in bone height were evaluated by a comparison of the computed tomography scans acquired before treatment and after surgery (at 3 months and 5 years of the survey). Statistically significant differences between the times and the tooth sites were evaluated by nonparametric statistics (matched and independent), with P < .01. Forty patients were retrospectively selected. The preoperative height of the available alveolar bone was 2.9 ± 0.6 mm. A significant increase in bone height (P < .01) was found for both the first and the second surgery (3.1 ± 0.6 mm and 4.4 ± 0.6 mm, respectively). The overall bone height was measured at 3 years after the first surgery (10.3 ± 0.6 mm). Measurements of the bone height ranked for tooth positions showed no significant difference between premolars and molars. None of the selected patients registered an implant failure. Two-stage osteotome-mediated sinus elevation appeared to be a predictable technique that enabled practitioners to increase the bone height and to obtain successful outcomes even if the amount of bone was approximately 3 mm in height.

Clinical Safety Assessment of Autologous Freeze-Drying Platelet-Rich Plasma for Bone Regeneration in Maxillary Sinus Floor Augmentation: A Pilot Study.

The purpose of this clinical study is to evaluate the safety and preliminary efficacy of autologous freeze-drying platelet-rich plasma (FD-PRP) on bone regeneration in maxillary sinus floor augmentation as a preliminary pilot study. Five patients that required sinus floor augmentation to facilitate the placement of dental implants participated in this clinical study. The PRP was prepared from the autologous peripheral blood and was lyophilized and stored at −20 °C for 4 weeks before surgery. At surgery, triple-concentrated FD-PRP (x3FD-PRP) mixed with synthetic bone grafting materials was rehydrated following the transplantation into the sinus floor. The primary outcome was a safety verification of x3FD-PRP, evaluated in terms of the clinical course and consecutive blood tests. The secondary outcome was clinical efficacy focused on bone regeneration in sinus floor augmentation evaluated by radiographic examination and implant stability. There were no adverse events, such as systemic complications, excessive inflammatory reactions, severe infection, or local site healing complications, besides those on the usual course associated with surgery. Vertical augmented height was maintained, and the initial stability of implants was achieved post-operatively in 6 months. The results obtained in this study suggest that x3FD-PRP can be used safely for bone engineering in clinical practice. Further studies are required to draw a conclusion concerning the efficacy of x3FD-PRP since this was a pilot study with a single arm and a small sample size.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Compared with a Composite Grafting Material or Bone Substitute Alone: a Systematic Review and Meta-Analysis Assessing Volumetric Stability of the Grafting Material.

ABSTRACTObjectivesTest the hypothesis of no difference in the volumetric stability of the grafting material following maxillary sinus floor augmentation with autogenous bone graft compared with composite grafting material or bone substitute alone applying the lateral window technique.Material and MethodsMEDLINE (PubMed), Embase, Cochrane library and hand-search of relevant journals were conducted. Human studies published in English until the 9th of October 2020 were included. Outcome measures included three-dimensional volumetric changes of the grafting material and potential predictive parameters. Volumetric changes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval.ResultsElectronic search and hand-searching resulted in 102 entries. Four randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. The volumetric stability of the grafting material was significantly improved by mixing autogenous bone graft with a non-resorbable xenograft compared with autogenous bone graft. Meta-analyses assessing absolute and relative volumetric changes demonstrated no significant differences between autogenous bone graft compared with allogeneic bone graft, synthetic biomaterials combined with autogenous bone graft or used alone. Association between volumetric changes of the grafting material and potential predictive parameters were not assessed in the included studies.ConclusionsVolumetric reduction of the augmented area seems inevitable following maxillary sinus floor augmentation regardless of the grafting material. The volumetric stability of autogenous bone graft is improved with addition of xenograft compared with autogenous bone graft. However, conclusions drawn from this systematic review should be interpreted with caution since only four studies using three-dimensional radiographic measurements were included.

Long-Term Comparison of Survival and Marginal Bone of Implants with and without Sinus Augmentation in Maxillary Molars within the Same Patients: A 5.8- to 22-Year Retrospective Study

Maxillary sinus floor augmentation (MSFA) is widely used and considered a predictable procedure for implant placement. However, the influence of MSFA on implant survival and marginal bone loss (MBL) is still inconclusive. The purpose of this retrospective observational study is to evaluate the long-term genuine influence of MSFA on the survival and MBL of implants by comparing those with and without MSFA only in maxillary molars within the same patients. Thirty-eight patients (28 male and 10 female), with a total of 119 implants, received implants with and without MSFA, and were followed up for 5.8 to 22 years. Patient- and implant-related factors were assessed with a frailty model for implant survival and with generalized estimation equations (GEE) for MBL around the implant. No variables showed a statistical significance for implant failure in the frailty model. In GEE analysis for MBL, MSFA did not show any statistical significance. In conclusion, MSFA demonstrated no significant influence on implant failure and MBL in posterior maxilla in this study.

Factors influencing the sinus membrane thickness in edentulous regions: a cone-beam computed tomography study

BackgroundDuring implant treatment in the maxillary molar area, maxillary sinus floor augmentation is often performed to ameliorate the reduced alveolar bone height attributable to bone remodeling and pneumatization-induced expansion of the maxillary sinus. However, this augmentation may cause complications such as misplaced implants, artery damage, and maxillary sinus mucosal perforation; infections like maxillary sinusitis; and postsurgical complications such as bone graft leakage and postoperative nasal hemorrhaging. To reduce the complications during maxillary sinus floor augmentation and postoperative infections, we performed retrospective investigations of various systemic and local factors that influence pre-operative sinus mucosal thickness (SMT) by using cone-beam computed tomography (CBCT). Subjects included patients who underwent maxillary sinus floor augmentation in an edentulous maxillary molar area with a lateral approach. Pre-operative SMT, existing bone mass, and nasal septum deviation were measured using CBCT images. Relationships between SMT and the following influencing factors were investigated: (1) age, (2) sex, (3) systemic disease, (4) smoking, (5) period after tooth extraction, (6) reason for tooth extraction, (7) residual alveolar bone height (RBH), (8) sinus septa, and (9) nasal septum deviation. Correlations were also investigated for age and RBH (p < 0.05).ResultsWe assessed 35 patients (40 sinuses; 11 male, 24 female). The average patient age was 58.90 ± 9.0 years (males, 57.9 ± 7.7 years; females, 59.9 ± 9.4 years; age range, 41–79 years). The average SMT was 1.09 ± 1.30 mm, incidence of SMT > 2 mm was 25.0%, incidence of SMT < 0.8 mm was 50.0%, and the average RBH was 2.14 ± 1.02 mm. The factors that influenced SMT included sex (p = 0.0078), period after tooth extraction (p = 0.0075), reason for tooth extraction (p = 0.020), sinus septa (p = 0.0076), and nasal septum deviation (p = 0.038).ConclusionsFactors associated with higher SMT included male sex, interval following tooth extraction < 6 months, periapical lesions, sinus septa, and nasal septum deviation. Factors associated with SMT > 2 mm were sex and reason for tooth extraction, while factors associated with SMT < 0.8 mm were time following tooth extraction and nasal septum deviation. Despite the limitations of this study, these preoperative evaluations may be of utmost importance for safely conducting maxillary sinus floor augmentation.

The effect of anatomy on osteogenesis after maxillary sinus floor augmentation: a radiographic and histological analysis.

To assess how anatomy and osteogenesis correlated with results of maxillary sinus floor augmentation (MSFA). Patients with partial edentulism and advanced atrophy of the posterior maxillae (≤ 4 mm residual bone height, RBH) underwent MSFA with sole deproteinized bovine bone matrix (DBBM) through a lateral approach. After a 6 to 9-month healing period, bone core biopsies were obtained from the sites of implant insertion for histological evaluation. The correlations between anatomical and histomorphometric variables were analyzed in a multiple regression model. Forty-nine patients were recruited. One biopsy per patient was obtained from the augmented sinus. Thirty-seven bone core biopsies were intact and met the requirement for histomorphometry analysis. The mean (± standard deviation) percentages of vital bone (VB), remaining DBBM, and non-mineralized tissue were 18.25 ± 4.76%, 27.74 ± 6.68%, and 54.08 ± 6.07%, respectively. No statistically significant correlations were found between RBH and VB% (p = 0.44) or between sinus contour and VB% (p = 0.33). However, there was an inverse correlation between the sinus width (SW) and VB % (SW1: R2 = 0.13, p = 0.03; SW2: R2 = 0.15, p = 0.02). After a healing period of 6-9 months, wider sinuses augmented with DBBM alone tended to have a lower proportion of new bone formation, while RBH and sinus contour did not appear to affect osteogenesis after MSFA. This study emphasized the effect of anatomy on osteogenesis after MSFA. The result of the study may have an indication to the clinician that SW is a consideration when selecting the bone grafting material and deciding the healing period of MSFA.

Clinical and Histological Outcomes of Maxillary Sinus Floor Augmentation With Synthetic Bone Substitutes for Dental Implant Treatment: A Meta-Analysis.

The main objective of this study was to compare the clinical and histological results of synthetic bone substitutes used in maxillary sinus floor augmentation. A systematic review and meta-analysis was performed by searching the PubMed/MEDLINE, Scopus, and Cochrane databases for studies of the success of endosseous dental implant, implant failure, peri-implant marginal bone loss, newly formed bone, and residual bone graft material. After the search, 10 randomized clinical trials were included, with 4 studies ranging from low to unclear risk of bias were used for meta-analysis, comparing biphasic calcium phosphate (BCP) and deproteinized bovine bone (DBB). A greater amount of residual graft material (mean difference [MD]: -4.80 mm; 95% CI: -9.35 to -0.26; P = .040) was found in the DBB group. No other statistically significant differences were found between BCP and DBB for the remaining outcomes. Our results suggested that BCP can be considered a suitable alternative to DBB in maxillary sinus floor augmentation due to its clinical and histological results.

Application of hydroxyapatite/collagen composite material for maxillary sinus floor augmentation.

The aim of this study was to clarify whether hydroxyapatite/collagen composite material (HAp/Col) could be useful as a graft material for maxillary sinus floor augmentation (MSFA). MSFA and implant placement were performed simultaneously. When the lateral approach was employed, 3 out of 19 implants failed in 3 maxillary sinuses (success rate; 84.2%), and in these cases the alveolar bone heights, cortical bone thicknesses and values of the implant stability quotient were smaller. If alveolar the bone height, cortical bone thickness, and healing period are optimized, HAp/Col can be a useful graft material for MSFA.

Comparison of 4 sinus augmentation techniques for implant placement with residual alveolar bone height ≤3 mm.

This study compared implant outcomes following maxillary sinus floor augmentation (MSFA) in edentulous patients with a residual alveolar bone height ≤3 mm. Four techniques were evaluated: 1-stage bone-added osteotome sinus floor elevation procedure (BAOSFE) with simultaneous implant placement; 2-stage BAOSFE with delayed implant placement; 1-stage lateral window sinus floor elevation with simultaneous implant placement; and 2-stage lateral window sinus floor elevation with delayed implant placement. Patients were followed for 18 to 72 months (mean: 52.5 months) after prosthesis placement. Data were analyzed with cone-beam computed tomography. A total of 96 implants from 71 patients were analyzed; pretreatment, there were no significant differences between patients. Total implant survival was 98.9%. The mean residual bone height was significantly higher in the 1-stage BAOSFE group than the other groups (P < .01); 1 implant in this group failed at 3 months. There was no significant difference in total bone height gain between groups. However, the bone height gain of 1st sinus lifting with 2-stage BAOSFE was significantly lower than the 2-stage lateral window procedure (P < .01). There was no prosthesis failure. The favorable implant outcomes suggest these 1-stage and 2-stage MSFA procedures should be considered as alternative treatment options for patients with extremely atrophic posterior maxilla.

The Influence of Residual Alveolar Bone Height on Graft Composition after Maxillary Sinus Augmentation Using Two Different Xenografts: A Histomorphometric Comparative Study.

Aim: To evaluate the hypothesis of a correlation between the preoperative residual alveolar bone height (RBH) and graft maturation after maxillary sinus floor augmentation procedures using two different bone substitutes. Methods: A total of 20 patients who underwent unilateral maxillary sinus floor augmentation with either mineralized deproteinized bovine bone (DBBM) or a xenograft enriched with polymer and gelatin (NBS) were included in this prospective study. Six months after sinus surgery, bone biopsies were harvested with a 3.2 mm diameter trephine bur, prior to dental implant placement. Histomorphometric analysis was performed, and the results were correlated with the individual RBH. Implants were loaded after 5 months of insertion, and 1-year implant success and marginal bone level change were assessed. Results: RBH was 2.17 ± 1.11 mm (range 0.5–3.5 mm) and 2.14 ± 0.72 mm (range 0.5–3.0 mm) in the NBS and DBBM group, respectively. The biopsy analyses for the DBBM group showed woven bone increases by 5.08% per 1-mm increment of RBH; medullary spaces decreased by 9.02%, osteoid decreased by 4.4%, residual biomaterial decreased by 0.34%, and lamellar bone increased by 5.68% per 1-mm increase of RBH. In the NBS group, samples showed woven bone increases by 8.08% per 1-mm increase of RBH; medullary spaces decreased by 0.38%; osteoid increased by 1.34%, residual biomaterial decreased by 0.58%, and lamellar bone decreased by 5.50% per 1-mm increase of RBH. There was no statistically significant difference in the correlation between RBH and lamellar bone, woven bone, and osteoid, independently of the material used. Implant success was 100% in both groups, and marginal bone loss was 1.02 ± 0.42 mm in DBBM and 0.95 ± 0.31 mm in the NBS group after the 1-year follow-up. Conclusion: In spite of the absence of significance, the observed trend for woven bone to increase and medullary spaces to decrease when RBH increases deserves attention. Residual bone dimension might be a determinant in the bone graft maturation after maxillary sinus augmentation.

Maxillary sinus floor augmentation through bone densification

Presenting a case of maxillary sinus lifting through alveolar crest by means of bone compacting from bone densification with drills and immediate placement of the dental implant (fixture). Patients who suffer from alveolar bone insufficiency present a common problem in the recovery from osseointegration implants, when a minimum remaining bone extension is necessary for implant stability.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Alone Compared with Alternate Grafting Materials: a Systematic Review and Meta-Analysis Focusing on Histomorphometric Outcome.

ABSTRACTObjectivesThe objective of present systematic review was to test the hypothesis of no difference in histomorphometric outcome after maxillary sinus floor augmentation with autogenous bone graft alone compared with alternate grafting materials applying the lateral window technique.Material and MethodsMEDLINE (PubMed), Embase and Cochrane library search in combination with hand-search of relevant journals were conducted. Human studies published in English until the 25th of March, 2020 were included. Histomorphometric outcomes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval (CI).ResultsElectronic search and hand-searching resulted in 1902 entries. Sixteen randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. Descriptive statistics showed comparable or improved histomorphometric outcomes with autogenous bone graft. Meta-analysis revealed a mean difference of -7.1% (CI = -11.0 to -3.2) indicating a significant higher amount of bone after maxillary sinus floor augmentation with autogenous bone graft compared with alternate grafting materials. Subgroup analysis demonstrated a non-significantly differences of -3.7% (CI = -10.9 to 3.4), -11.5% (CI = -25.9 to 2.8), 2.2% (CI = -16.9 to 21.3), and -4.6% (CI = -14.4 to 5.2), when autogenous bone graft was compared with allogeneic bone graft, xenograft, composite grafting materials involving xenograft or synthetic biomaterial mixed with autogenous bone graft, respectively.ConclusionsMaxillary sinus floor augmentation with autogenous bone graft seems to facilitate improved histomorphometric outcomes compared with alternate grafting materials. However, the included studies were characterised by an unclear risk of bias and various methodological confounding factors. Hence, the conclusions drawn from the results of present study should be interpreted with caution.

The vertical course of bone regeneration in maxillary sinus floor augmentations: A histomorphometric analysis of human biopsies.

BackgroundMaxillary sinus floor augmentation (MSFA) is a well‐established and predictable augmentation method in severely resorbed maxillae. However, data on the vertical course of bone graft consolidation within the maxillary sinus are rare. The aim of the present study was to quantify the vertical distribution of new bone formation (nBF) in MSFA and to characterize the vertical gradient of bone graft consolidation.MethodsEighty‐five human sinus biopsies were harvested 6 ± 1 months after MSFA. Histological thin‐ground sections were prepared and histomorphometrically analyzed. The volume of newly formed bone (nBV/TV) was measured in serial zones of 100 μm proceeding from the bottom of the sinus floor (SF) up to the apical top of the biopsy. The gradient of nBV/TV within the augmentation area was determined by the vertical distribution of nBV/TV along these zones.ResultsIn the premolar region, nBV/TV slightly declined from 20.4% in the zone adjacent to the SF to 17.7% at a distance of 8 mm. The gradient was steeper in the molar region: nBV/TV decreased from 18.7% to 12.8%. This decline was even more distinct when the volume fraction and the height of the residual bone of the SF were low.ConclusionsnBF follows a gradient from native bone of the SF towards the apical part of the augmentation area. The distance to primordial bone thus plays a critical role for bone regeneration in MSFA, particularly in the molar region.

Evaluation of maxillary sinus floor augmentation with the crestal approach and beta-tricalcium phosphate: a cone-beam computed tomography 3- to 9-year follow-up

BackgroundWe performed maxillary sinus floor augmentation using the crestal approach and beta-tricalcium phosphate (β-TCP) and a long-term evaluation using cone-beam computed tomography (CBCT).MethodsTwenty-three patients (30 implants) underwent sinus floor augmentation using the osteotome technique. Subjects underwent CBCT imaging before surgery, immediately after surgery, and at follow-up (≥ 3 years after surgery). We measured the changes in height of the augmented sinus floor (SL), the augmented bone above apex of the implant (BH), and the implant length that projected into the sinus (IL).ResultsThe mean SL decreased from 6.54 ± 1.51 (immediately after surgery) to 3.11 ± 1.35 mm (follow-up). The mean BH decreased from 3.17 ± 0.97 to − 0.25 ± 1.19 mm; the maxillary sinus floor in many implants was near the apex at follow-up. The SL at follow-up showed a strong correlation with the IL (p = 0.0057).ConclusionsOsteotome sinus floor elevation with beta-tricalcium phosphate was clinically effective. Cone-beam computed tomography analysis revealed that ≥ 3 years after surgery, the maxillary sinus floor was near the apex of the implant.

Graftless Maxillary Sinus Floor Augmentation with Simultaneous Porcine Bone Layer Insertion: A 1- to 5-Year Follow-up Study.

Evidence suggests that maxillary sinus floor augmentation via a lateral approach can be performed without positioning a bone graft inside, when one or more implants can be placed simultaneously. The aim of this study was to test if the placement of a porcine cortical bone layer underneath the sinus membrane can increase bone formation and implant stability. One hundred seventy-two patients with posterior maxilla atrophy needing implant rehabilitation were selected. Two hundred six sinus augmentation procedures were performed via a lateral approach, and 295 implants were placed in the same session of the sinus elevation surgery. In all the surgeries, a porcine cortical bone layer was placed underneath the sinus membrane, without using any graft material. After 6 to 7 months of healing, the implants were uncovered, then restored with porcelain-fused-to-metal crowns and monitored with a followup of 1 to 5 years. The implant cumulative success rate was 95.2%, while the residual bone crest height changed from 2.67 ± 1.11 mm to 12.54 ± 1.42 mm, with an increase of 9.87 mm on average. Marginal bone resorption was 0.83 mm on average after 1 year of loading, while the mean implant stability measured at the moment of implant placement and 6 to 7 months later increased from an implant stability quotient (ISQ) of 62.61 ± 5.7 to an ISQ of 70.07 ± 8.2. This study confirms the validity of the graftless sinus elevation surgery when simultaneous implant placement is performed. The use of a porcine cortical bone layer seems to increase, from a radiologic point of view, the amount of bone around the implants, reducing healing time, cost, and biologic complications for the patient.

Promoting Osseointegration of Dental Implants in Dog Maxillary Sinus Floor Augmentation Using Dentin Matrix Protein 1-Transduced Bone Marrow Stem Cells.

Beta-tricalcium phosphate (β-TCP) has been employed successfully as a synthetic graft material in maxillary sinus floor augmentation (MSFA) for placing dental implants. However, the lack of osteogenic and osteoinductive properties of this substitute invariably results in bone regeneration of low quality and quantity. The purpose of this study was to determine whether loading dentin matrix protein-1 (DMP1) gene-modified bone marrow mesenchymal stem cells (BMSCs) onto β-TCP promoted bone regeneration and osteointegration of dental implants in MSFA of dogs. BMSCs were transduced with a lentiviral vector overexpressing the DMP1 gene (Lenti-DMP1) and with a lentiviral vector overexpressing enhanced green fluorescent protein (Lenti-EGFP) in vitro and were loaded into β-TCP scaffolds for autologous sinus grafting. Beagles received bilateral MSFA with four biomaterials (① Lenti-DMP1-transduced BMSCs/β-TCP, ② Lenti-EGFP-transduced BMSCs/β-TCP, ③ BMSCs/β-TCP, ④ β-TCP) and simultaneous implant placement at each sinus. Twelve weeks post operation, the maxillae were explanted, and every sinus was evaluated by radiographic observation, micro-CT and histological analysis. The osteogenic outcomes of bone regeneration and osseointegration were compared between the four groups. The sinuses grafted with Lenti-DMP1-transduced BMSCs/β-TCP constructs presented a significantly higher increase in compact radiopaque area, higher local bone mineral densities, greater bone-implant contact and greater bone density when compared to other three groups. These results demonstrated that combinations of β-TCP and DMP1 gene-modified BMSCs could be used to construct tissue-engineered bone to enhance mineralization of the regenerated bone and osseointegration of dental implants in MSFA.

Clinical outcome of implants placed in grafted maxillary sinus via lateral approach: A 10-year follow-up study

Background/purposeThe maxillary sinus floor augmentation (MSFA) technique is frequently used for the preparation of implant sites in the maxillary region. The aim of this study was to investigate the 10-year outcome of dental implants placed in a grafted maxillary sinus, and identify possible risk factors for implant failure. Materials and methodsWe retrospectively analyzed 202 implants after MSFA in 97 patients from January 2008 to April 2009. The outcome variables were 1) 10-year cumulative survival rate of the implant, 2) risk factors for implant failure, and 3) correlation between preoperative residual bone height (RBH) and graft materials in terms of implant survival. Graft materials used were divided into five different groups: autogenic, allogenic, xenogenic, combination of allogenic and xenogenic, or combination of autogenic and xenogenic graft. ResultsThe cumulative 10-year survival rate for the implants was 96.04%. In regions with a residual bone height of 5.0 mm and less, greater RBH was preferable for long-term implant survival (odds ratio = 3.475; p = 0.035). Implant survival was not significantly different with different graft materials, even when RBH was unfavorable. ConclusionThe placement of dental implants with MSFA is a reliable procedure. Further, RBH is an important predictor of long-term implant survival.

Sinus Floor Augmentation Using Recombinant Human Bone Morphogenetic Protein-2 With Hydroxyapatite: Volume Assessment

The aim of this study was to assess the efficacy of using bone morphogenetic protein-2 with hydroxyapatite granules (BMP-2/hydroxyapatite) during augmentation of maxillary sinus floor, with respect to changes in volume, relative to conventional bone graft materials. Twenty of 25 patients in the BMP-2/hydroxyapatite group, and 16 of 33 patients in the conventional materials group met the criteria for inclusion in this study. Computed tomography scans were performed preoperatively, immediately postoperatively, and at follow-up, approximately 6 months postoperatively. Changes in volume and height of both grafted materials were measured using 3-dimensional reconstruction software; these changes were compared between groups. The mean (standard deviation) volumetric changes were 0.25 (0.11) cc and -0.07 (0.35) cc, and the mean rates of volumetric changes were 26.44% (7.78%) and -2.92% (30.92%) in BMP-2/hydroxyapatite and conventional materials groups, respectively. The mean height changes were 0.34 (0.73) mm and -0.63 (1.07) mm, and the mean rates of height changes were 3.67% (7.57%) and -5.95% (9.98%) in BMP-2/hydroxyapatite and conventional materials groups, respectively. Compared with the conventional materials group, the BMP-2/hydroxyapatite group showed better maxillary sinus floor augmentation results in terms of volumetric changes and grafted material densities, and can provide predictably reliable outcomes.

Injectable thermosensitive chitosan/gelatin-based hydrogel carried erythropoietin to effectively enhance maxillary sinus floor augmentation in vivo

ObjectiveMaxillary sinus floor augmentation (MSFA) is commonly used to increase the alveolar bone height in the posterior maxilla before implant placement. In the present study, we evaluated if the injectable thermosensitive chitosan/β-sodium glycerophosphate disodium salt hydrate/gelatin (CS/GP/GA) hydrogel carried erythropoietin (EPO) could enhance the new bone formation for MSFA in vivo. MethodsEPO-CS/GP/GA hydrogel was prepared by ionic crosslinking. Then, characteristics of EPO-CS/GP/GA were evaluated by morphology, injectable property and pH on the gelling time (GT). The release profile of EPO was evaluated by enzyme linked immunosorbent assay (ELISA), and effects of EPO on proliferation and osteoblastic differentiation of bone marrow stromal cells (BMSC) were analyzed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and reverse transcription quantitative real-time PCR (RT-qPCR), respectively. Finally, EPO-CS/GP/GA was injected into the maxillary sinus floor of the rabbit to test the potential application for MSFA. ResultsResults showed that GT was decreased with the increase of pH value. The GT was 110±15s at pH 7.0. SEM images showed that the CS/GP/GA hydrogel had a sponge network structure. Results from ELISA assay revealed that the cumulative release of EPO from the EPO-CS/GP/GA hydrogel reached 67% at 4h, and 94% at 15 days. MTT assay showed that EPO within EPO-CS/GP/GA hydrogel could significantly promote proliferation of BMSCs compared to control group (p<0.001) . Results of RT-qPCR assays demonstrated that the expression of Sp7, Runx2, Col I and Alp were significantly increased from EPO-CS/GP/GA group compared to control group on day 14 (p<0.001). Importantly, EPO-CS/GP/GA hydrogel could significantly induce bone formation (81.98mm3) compared with control group (43.11mm3) after 12 weeks post-implantation in vivo. The calculation of thickness of mesenchymal condensation indicated that thickness of mesenchymal condensation was significantly increased from EPO-CS/GP/GA group (∼121.4μm) compared to control group (∼37μm) resulting in enhancing intramembranous ossification. SignificanceThe EPO-CS/GP/GA hydrogel provides a novel strategy for MSFA with a minimally invasive way.

Comparison of two anorganic bovine bone in maxillary sinus lift: a split-mouth study with clinical, radiographical, and histomorphometrical analysis

BackgroundAnorganic bovine bone (Bio-Oss®) has been extensively used for reconstruction of posterior area of maxilla in sinus lift procedure; however, a new graft material (Lumina-Bone Porous®), that has a different manufacturing process, has not been yet compared in clinical and histological terms. The manufacturing process of bovine bone graft is related to size and porosity of the particles, and this can change osteoconductive property of the material and bone formation. The use of Lumina-Porus® could improve bone formation, reduce the remaining particles of the biomaterial using a low-cost material. The aim of this research was to compare the clinical, radiological, and histomorphometrical results from maxillary sinus lift with two different anorganic bovine bone substitutes Bio-Oss® (control) and Lumina-Bone Porous® (test).ResultsA split-mouth study was performed with 13 volunteers. The mean bone ridge height in the deepest portion of maxillary sinuses floor was 3.11 ± 0.83 mm in the Bio-Oss® and 2.38 ± 0.75 mm in the Lumina-Bone Porous®. After sinus lift, the Bio-Oss® group shows bone ridge height of 11.56 ± 2.03 mm and Lumina-Bone® of 10.62 ± 1.93 mm. The increase in alveolar bone height scores was significant between pre-augmentation and 6 months after SL in both groups (p < 0.001). No statistical significant difference in newly formed bone in the Bio-Oss® group (20.4 ± 5.4%), and Lumina-Bone Porous® (22.8 ± 8.5%) was histomorphological observed (p > 0.05). On the other hand, the residual graft particles showed significant difference between the Bio-Oss® group (19.9 ± 8.6%) and Lumina-Bone Porous® (14.6 ± 5.6%) (p < 0.05). The survival rate of dental implants for augmented area with Lumina Bone Porous® was 88.88%, while for Bio-Oss® group was 100%.ConclusionBoth materials Bio-Oss® and Lumina-Bone Porous® can be used in the maxillary sinus floor augmentation with good predictability in clinical, radiographical, and histological point of view.