Hyperglycemia is detrimental to bone healing and quality. Oral administration of resveratrol may have protective effects on bone repair. This study investigated the impact of resveratrol on the bone anchorage of microtopographic or nanotopographic implants placed in the tibiae of hyperglycemic and euglycemic rats.Blood glucose, body weight, and implant removal torque were measured. Anchorage during the process of osseointegration, and later bone remodeling, were quantified by fitting a biphasic asymptotic curve. We hypothesized that resveratrol would enhance the process of osseointegration and reverse the detrimental effects of hyperglycemia.Hyperglycemic animals had elevated blood sugar levels and reduced weight gain; neither affected by resveratrol. Nanotopographic implant removal torque was increased by 1.2 times (p = 0.0002, 95 % CI [1.1,1.3]) compared to microtopographic implants. At 84 days, linear modeling indicated that the untreated hyperglycemic groups’ removal torque values were half of the untreated euglycemic groups’ (p = 0.0005, 95 % CI [0.3,0.8]). This reduction in anchorage is associated with less virtual distal implant drift. Resveratrol treatment increased anchorage in hyperglycemic rats by 1.8 times (p = 0.005, 95 % CI [1.1,2.8]), returning measurements to euglycemic levels.Higher bone anchorage was seen for nanotopographic implants, compared to microtopographic implants during the process of osseointegration, but the nanotopographic surface provided no further advantage during bone remodeling. The hyperglycemic condition significantly reduced bone anchorage at later time points, which was eradicated by resveratrol administration. These results may be explained by hyperglycemia and resveratrol disrupting and recovering microcirculation respectively, indicating that resveratrol affects microcirculation rather than the process of bone remodeling.

Dental implant coronal surfaces designed with the primary goal of maintaining crestal bone levels may also promote bacterial adhesion, leading to soft tissue inflammation and peri-implant bone loss. Achieving an optimal surface roughness that minimizes bacterial adhesion while preserving crestal bone is crucial. It is hypothesized that a specific threshold surface roughness value may exist below which, and above which, initial bacterial adhesion does not statistically change. This study evaluated 12 commercially available and 2 custom-designed implant surfaces for their physicochemical properties and initial bacterial adhesion, as represented by Streptococcus oralis ( S. oralis ) the dominant initial colonizer of the successive waves of bacterial consortia that result in plaque and biofilm formation. Implants were immersed in a S. oralis suspension for 4 h, after which microbial viability was assessed. Marked differences were observed in surface roughness, chemical composition, and wettability, and S. oralis adhesion. Surfaces with Sa > 1 μm had significantly more adherent bacteria after 4 h compared to those with Sa < 1 μm, despite complexity. Adding nanotopography to dual-acid etched surfaces further reduced bacterial adhesion compared to surfaces without these features. The role of chemical composition and wettability was less influential than roughness. In conclusion, there is a cut-off threshold roughness around Sa = 1 μm, above which the adhesion of bacteria increases significantly to a plateau level; while below which, bacterial adhesion is equivalent to a machined surface despite the surface texture of the implant collar.

Objective: To compare in vivo, the acute anti-inflammatory effects of a lysate derived from human umbilical perivascular mesenchymal cells with the cells themselves in both an established hind-paw model of carrageenan-induced inflammation and also in the inflamed temporomandibular joint. Study Design: Human umbilical cord perivascular cells were harvested and cultured in xeno-and serum-free conditions to P3. In addition, P3 cells were used to prepare a proprietary 0.22 micron filtered lysate. First, CD1 immunocompetent mice underwent unilateral hind-paw injections of carrageenan for induction of inflammation, followed immediately by treatment with saline (negative control), 1% cell lysate, or viable cells. The contralateral paw remained un-injected with carrageenan. Paw circumference was measured prior to injections and 48 hr later and myeloperoxidase and TNF-alpha concentrations were measured post-sacrifice in excised tissue. Second, immunocompetent Male Wistar rats underwent unilateral intra-articular temporomandibular (TMJ) injections from the same treatment groups and were sacrificed at 4 and 48 hr post-injection. The contralateral TMJ remained un-injected with carrageenan. Articular tissue and synovial aspirates, from the treated TMJ were obtained for histologic and leukocyte infiltration analyses. Results: The lysate and cell-treated hind-paw demonstrated reduced tissue edema, and significantly lower concentrations of myeloperoxidase and TNF-alpha at 48 hr compared to untreated controls. Treated TMJs demonstrated lower concentrations of leukocytes in the synovium compared to controls and histologic evidence, in the peri-articular tissue, of reduced inflammation. Conclusion: In this preliminary study, both the human umbilical perivascular cells and a highly diluted lysate produced therefrom were anti-inflammatory.

PURPOSE:The purpose of this study was to show the full evolution of bone anchorage caused by the growth of secondary stability and to determine which empirical model would provide the best quantitative description of this growth.MATERIALS AND METHODS:The retention and anchorage of machined (M), grit-blasted and dual acid etched (BAE), and BAE implants with discrete crystals of calcium phosphate (+DCD) were evaluated with both ex vivo and in vivo methods. Ex vivo evaluation of implant retention was tested by measuring the force required to pull implants out of blood-filled osteotomies formed in bovine bone for up to 1 hour. In vivo measurements of bone anchorage were evaluated by reverse torque testing of implants placed in the proximal metaphysis of rat tibiae up to 28 days after initial placement. Four models were fit to the reverse torque results, and fits were evaluated by Bayesian and Akaike information criteria (BIC and AIC) and analysis of variance (ANOVA).RESULTS:AIC and BIC were 655.53 and 684.78, 472.53 and 512.74, 477.40 and 513.96, and 470.60 and 507.16 for the monomolecular, Richards, Gompertz, and logistic curves, respectively. Comparison of the Richards and logistic curves by analysis of variance (ANOVA) resulted in a P value of .78. A comparison of the three implant types using the logistic curve found that M implants had an earlier inflection point compared with BAE implants (P = .038), and the BAE+DCD implants had the greatest peak anchorage and were significantly greater than both M (P < .0001) and BAE implants (P = .005).CONCLUSION:Bone anchorage was found to follow sigmoidal growth, which was best described by the logistic function. Further comparison of the fit values for the logistic curve shows that both overall anchorage and timing of bone anchorage are influenced by implant surface topography.

Titanium implants have shown considerable success in terms of achieving quick and long-lasting stability in bone through the process of osseointegration. Further work aims to improve implant success rates by modifying implant design on the nano-, micro-, and macro- scales with the goal of achieving higher levels of bone anchorage more quickly. However, the most frequently used methods of analysis do not investigate bone anchorage as a whole but as a series of discrete points, potentially missing relevant insight which could inform the effects of topography on these 3 scale ranges. Herein we utilize an asymptotic curve fitting method to obtain a biologically relevant description of reverse torque data and compare the anchorage of 12 different implant groups. Implant surface topography had a significant effect on the rate and degree of anchorage achieved during the initial bone formation period of osseointegration but was not found to influence the relative change in anchorage during bony remodeling. Threaded implants significantly decreased the time required to reach peak anchorage compared to non-threaded implants and implants with micro-topographically complex surfaces required greater torque to be removed than implants without such features. Nanotopography increased overall anchorage and decreased the time required to reach peak anchorage but to a lesser degree than microtopography or macrogeometry respectively. The curve fitting method utilized in the present study allows for a more integrated analysis of bone anchorage and permits investigation of osseointegration with respect to time, which may lead to a more targeted approach to implant design.

Uncontrolled diabetes is associated with increased risk of bony fractures. However, the mechanisms have yet to be understood. Using high-resolution synchrotron micro-CT, we calculated the changes in the microstructure of femoral cortices of streptozotocin-induced hyperglycemic (STZ) Wistar Albino rats and tested the mechanical properties of the mineralized matrix by nanoindentation. Total lacunar volume of femoral cortices increased in STZ group due to a 9% increase in lacunar density. However, total vascular canal volume decreased in STZ group due to a remarkable decrease in vascular canal diameter (7 ± 0.3 vs. 8.5 ± 0.4 µm). Osteocytic territorial matrix volume was less in the STZ group (14,908 ± 689 µm 3 ) compared with healthy controls (16,367 ± 391 µm 3 ). In conclusion, hyperglycemia increased cellularity and lacunar density, decreased osteocyte territorial matrix, and reduced vascular girth, in addition to decreasing matrix mechanical properties in the STZ group when compared with euglycemic controls.

OBJECTIVE:To compare the contributions of implant hydrophilicity and nanotopography on anchorage in bone. The effect of elevated calcium surface chemistry on bone anchorage was also investigated.MATERIALS AND METHODS:A full factorial study design was implemented to evaluate the effects of ultraviolet (UV) light and/or sodium lactate (SL) and discrete crystalline deposition of nanocrystals (DCD) treatments on the osseointegration of dual acid-etched (AE) titanium alloy (Ti6Al4V) and grit blasted and AE (BAE) commercially pure titanium (CpTi) implants. Sodium hydroxide (NaOH)-treated CpTi implants were immersed in simulated body fluid (SBF) to increase calcium surface chemistry. Implants were placed in the femora of Wistar rats and tested using pull-out testing (BAE implants: 5, 9, 14 days) or tensile testing (AE implants: 9 days, NaOH implants: 28 days).RESULTS:Ti6Al4V-AE implants with DCD- and UV-treated surfaces significantly increased bone anchorage compared with untreated Ti6Al4V-AE alloy implants. Pull-out testing of BAE-CpTi implants with the DCD treatment showed increased disruption force values compared with surfaces without the DCD treatment at 5, 9 and 14 days by 4.1N, 13.9N and 15.5N, respectively, and UV-treated implants showed an increase at 14 days by 8.4N. No difference was found between NaOH + SBF and NaOH + H2 O groups.CONCLUSIONS:Bone anchorage of implants was found to be improved by UV-treating implants or nanotopographically complex surfaces. However, implant nanotopography was found to have a greater contribution to the overall bone anchorage and is more consistent compared with the time-dependent nature of the UV treatment.

PURPOSE:Osseointegration has been defined in many ways, from both basic science and clinical perspectives, but generally represents the restoration of bony homeostasis following implant placement and is usually judged by some form of bone/implant disruption test. In this study, bone anchorage to two different implant surfaces, in tensile and shear modes, was compared to investigate the relation between implant surface topography and osseointegration over time. The purpose was to determine if mathematical parameters could be derived that would reflect the biologic relevance of the implant surface design.MATERIALS AND METHODS:Rectangular titanium implants (n = 244) were placed in the distal femora of 122 male Wistar rats proximal to the knee joint. Implants were either microsurfaced (MS) or nanosurfaced (NS). Animals were euthanized at one of six time points ranging from 5 days to 6 months, and the force required to disrupt the bone implant interface, in either shear or tension, was measured using an Instron machine. Data were analyzed by fitting the function F = C (1-e-x/τ), where F is the measured disruption force, C is the predicted average maximum disruption force, x is the time postimplantation, and τ is a time constant defined as the time required for F to reach 63.2% of C.RESULTS:Analysis showed that shear testing resulted in significantly larger values of C than seen in tension, but no significant difference was observed when comparing the values of C for NS and MS implants in shear (P = .7). Thus, in accord with clinical reports, both implants performed equivalently at longer implantation periods. The differences in C were significant in tension (P < .05). Importantly, NS implants had a significantly smaller τ than the MS implants (P < .01, in shear), but no significant differences were observed in τ due to mechanical testing vector. The disruption force values reached a plateau with time, representing bony homeostasis as a result of osseointegration. With time, both implant surfaces reached the same maximum (C) values, in shear. However, the value of τ was smaller in NS compared to MS implants, which represented a higher rate of osseointegration.CONCLUSION:Thus, τ emerges as a measureable and biologically relevant parameter that can be employed to compare the osseointegration potential of putative implant surfaces.

The aim of this work was to investigate the effect of implant surface design on early bone anchorage in the presence of hyperglycemia. 108 Wistar rats were separated into euglycemic (EG) controls and STZ-treated hyperglycemic (HG) groups, and received bilateral femoral custom rectangular implants of two surface topographies: grit blasted (GB) and grit-blast with a superimposed calcium phosphate nanotopography (GB-DCD). The peri-implant bone was subjected to a tensile disruption test 5, 7, and 9 days post-operatively (n = 28/time point); the force was measured; and the residual peri-implant bone was observed by scanning electron microscopy (SEM). Disruption forces at 5 days were not significantly different from zero for the GB implants (p = 0.24) in either metabolic group; but were for GB+DCD implants in both metabolic groups (p < 0.001). Contact osteogenesis was greater on GB-DCD than the GB surface. The nano-and micro-surfaced implants showed significantly different disruption forces at all time points (e.g. >15 N and <5 N respectively at 9 days). Such differences were not seen within the GB implants, as all values were very low (<5 N). Even in hyperglycemia the GB-DCD surface outperformed the GB surfaces in both metabolic groups. Significantly, SEM of peri-implant bone showed compromised intra-fibrillar collagen mineralization in hyperglycemia, while inter-fibrillar and cement line mineralization remained unaffected. Enhanced bone anchorage to the implant surfaces was observed on the nanotopographically complex surface independent of metabolic group. The compromised intra-fibrillar mineralization observed provides a mechanism by which early bone mineralization is affected in hyperglycemia.Statement of SignificanceIt is generally accepted that the hyperglycemia associated with diabetes mellitus compromises bone quality, although the mechanism by which this occurs is unknown. Uncontrolled hyperglycemia is therefore a contra-indication for bone implant placement. It is also known that nano-topographically complex implant surfaces accelerate early peri-implant healing. In this report we show that, in our experimental model, nano-topographically complex surfaces can mitigate the compromised bone healing seen in hyperglycemia. Importantly, we also provide a mechanistic explanation for compromised bone quality in hyperglycemia. We show that intra-fibrillar collagen mineralization is compromised in hyperglycemia, but that interfibrillar and cement line mineralization, remain unaffected. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Event Abstract Back to Event Quantifying the contributions of implant hydrophilicity and nanotopography on bone anchorage Robert S. Liddell1, Zhen-Mei Liu2, Vanessa C. Mendes1 and John E. Davies1, 2 1 University of Toronto, Faculty of Dentistry, Canada 2 University of Toronto, Institute of Biomaterials and Biomedical Engineering, Canada Introduction: There is currently no consensus on the most effective treatments for improving the anchorage of an implant and bone. Both hydrophilicity and implant surface topography have been cited as being beneficial, however, the relative contributions of hydrophilicity and implant topography to bone anchorage are not known. Methods: Eight groups of rectangular, commercially pure titanium implants (n=20; Total=560 – see Figure 1) were placed bi-cortically in rat femora for 5, 9 or 14 days as well as 28 and 140 days for G1 and G5. Groups 5, 6, 7, and 8 were treated with discrete calcium phosphate (CaP) nanocrystals or DCD, increasing implant nanotopography, Groups 2, 4, 6 and 8 were treated by exposure to ultraviolet (UV) light to increase hydrophilicity, and Groups 3, 4, 7, and 8 were immersed in sodium lactate (SL) which was done to maintain the effects of the UV treatment. Bone anchorage was tested using a bi-cortical pullout test and disruption force data was compiled and analyzed using the statistical software “R”. Linear modeling was used to analyze data which ranged from 5-14 days for all implant groups. Curve fitting using the function F=C-D∙e-x/τ, a generalized form of the asymptotic function, was also used for analyzing the data across all 5 timepoints for G1 and G5 implants. P values <0.05 were considered significant. Additional implants were examined by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and water contact angle evaluation (CA). Data was compared with legacy data obtained on similarly modified acid-etched titanium alloy (Ti64) samples using a pulloff test method. Results: Curve fitting of the G1 and G5 data showed that the DCD increased the rate of bone anchorage (P<0.05). Similarly, Groups 5-8 resulted in higher disruption values than Groups 1-4 (overall means 53.2N and 42.1N respectively; p<0.001), greater than any changes produced by the UV and/or SL treatments. The SL treatment, however, did show a statistically significant increase in removal force at day 5 (p<0.05). The UV treatment did not result in any significant differences. CA measurements were: G1=94°; G2=71°; G5=93°; G6=65°, but could not be measured accurately for SL implants because their surfaces were too wettable, resulting in the water running off the implant. XPS showed an increase in Ca and P due to DCD, however this was masked by the SL in G7 and G8. Discussion: As observed previously, the addition of nanotopography accelerated osseointegration, showing that the newly developed test method did not influence results. Analysis of the 5-14 day time points demonstrated that of all treatments, only DCD resulted in a significant increase in disruption force across all time points, although the SL treatment did demonstrate increased disruption forces at 5 days. From XPS it was determined the SL left a film over the sample surface thicker than the sampling depth of 7-10nm. Simply rinsing the implant with distilled water for a short amount of time removed this layer revealing the underlying surface in SEM. Conclusion: Increased implant hydrophilicity was only observed to have an effect on implant removal forces at the earliest of examined timepoints. In contrast, increased implant nanotopography showed increased removal forces up to 14 days. Jian Wang; Susan Carter; Jean Kontagiannis; Rainer de Guzman; Zimmer Biomet Dental Keywords: Implant, Surface modification, nanotopography, Bone repair Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: New Frontier Oral Topic: Interfacial phenomena Citation: Liddell RS, Liu Z, Mendes VC and Davies JE (2016). Quantifying the contributions of implant hydrophilicity and nanotopography on bone anchorage. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.00060 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Robert S Liddell Zhen-Mei Liu Vanessa C Mendes John E Davies Google Robert S Liddell Zhen-Mei Liu Vanessa C Mendes John E Davies Google Scholar Robert S Liddell Zhen-Mei Liu Vanessa C Mendes John E Davies PubMed Robert S Liddell Zhen-Mei Liu Vanessa C Mendes John E Davies Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

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Event Abstract Back to Event Surface topography of implants drives bone anchorage Zhen-Mei Liu1*, Robert Liddell1* and John E Davies1, 2* 1 Faculty of Dentistry, University of Toronto, Canada 2 Institute of Biomaterials and Biomedical Engineering, University of Toronto, Canada Introduction: Titanium (Ti) is widely used as a dental implant material[1]. We, and others, have shown that implant surface topography, especially at the nano-scale, plays a significant role in promoting bony healing[2],[3]. However, we have generally superimposed discrete calcium phosphate (CaP) nanocrystals (DCD), on Ti surfaces, to create a nanotopographic complexity. This begs the question; Is it the topography, or CaP chemistry that is responsible for the improved implant performance. Thus, we report here the comparative performance of nano-Ti surfaces created within the surface Ti oxide surface with those functionalized with CaP crystals, using a bone anchorage test. Materials and Methods: 380 Custom-made commercially pure titanium implants with machined surfaces were made and split into 6 groups: (A) Machined (B) A+DCD (C) A+NaOH (D) C+SBF immersion (E) C+H2O immersion (F) A+anodized. Group D was prepared to add Ca2+ ions to the complex NaOH surface. Each surface was examined by both scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). All implants were sterilized using 25kGy γ-irradiation. The implants were placed into the femora of male Wistar rats, which were sacrificed after 14, 28, 56, 98, or 140 days. The femora were harvested and then trimmed to the width of the implant, leaving the implant in between two bony arches. The force required to disrupt the model was measured with an Instron™. Data was collected and compiled using the statistical software “R”. P values <0.05 were considered significant. Results: SEM of all implant groups showed a relatively smooth surface with some micro-scale features at low magnification. At higher magnification, Group B had approximately 50% coverage of DCD, Groups C-E had a complex interconnected nanoporous structure with pore sizes up to 110 nm. Group F implants were covered with nanotubes of approximately 100nm diameter. XPS confirmed an increase in Ca on the surface of Group D (2.98%) as compared to Group C (0.66%) due to the SBF treatment. Disruption forces were seen to increase with time for all, but Groups A and B of which the disruption forces were significantly smaller than all other groups. Significant differences were found between all group pairs, with exceptions of C/F, and D/E (Figure 1) at 28 days. Discussion: At all time points, the disruption forces for Groups A and B were near zero, indicating little bony anchorage to these surfaces. On the contrary Groups C and F showed significantly increased disruption forces (C = 16.8 x B at 28 days), indicating that the Ti surface oxide nanofeatures were having a profound effect, without the addition of a CaP phase. Interestingly, when this complex oxide surface was functionalized with Ca2+ ions (Group D) the disruption force decreased: However, this was also the case in Group E, which suggested that immersion in an aqueous solution had weakened the surface oxide structure. Conclusion: Bone anchorage results from implant surface topographical complexity rather than CaP chemistry. Implants were provided by Zimmer BioMet Dental.References:[1] Y Shivata, Y Tanimoto, J Prosthodont Res 2015; 59:20.[2] JE Davies, et al Biomaterials 2014: 35:25.[3] G Mendonca, et al Biomaterials 2008; 29:3822. Keywords: Implant, Surface modification, nanotopography, surface topolography Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Biomaterials in dental applications Citation: Liu Z, Liddell R and Davies J (2016). Surface topography of implants drives bone anchorage. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.01816 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. * Correspondence: Dr. Zhen-Mei Liu, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, Email1 Dr. Robert Liddell, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada, rob.liddell@mail.utoronto.ca Dr. John E Davies, Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada, davies@ecf.utoronto.ca Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Zhen-Mei Liu Robert Liddell John E Davies Google Zhen-Mei Liu Robert Liddell John E Davies Google Scholar Zhen-Mei Liu Robert Liddell John E Davies PubMed Zhen-Mei Liu Robert Liddell John E Davies Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. 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We investigated the possibility of employing human umbilical perivascular cells (HUCPVCs) within the context of finding an alternative source of mesenchymal stromal cells (MSC) for bone tissue engineering. Since it has previously been reported that conditioned medium (CM) from osteogenic bone marrow (BM) MSCs can potentiate osteogenic differentiation in a secondary cell population, we also employed BM-MSCs to generate CM to stimulate osteogenesis in the HUCPVCs. The BM-MSCs were a commercially available immortalized human cell line. In vitro assays showed negligible levels of osteogenic gene expression in HUCPVCs compared to BM-MSC, but alkaline phosphatase was detected when HUCPVC were cultured in osteogenic medium in the presence of CM from BM-MSC. An in vivo assay employing a rat calvarial osteotomy defect, together with a collagen sponge scaffold, showed that HUCPVCs provided statistically significant bony repair compared to controls. BM-MSC loaded scaffolds were not statistically different from either controls or HUCPVCs. The addition of BM-MSC CM to HUCPVCs also produced no statistically significant difference to the bone formed by HUCPVCs alone. Our results demonstrate that the in vitro assays employed did not predict in vivo outcomes, and that the BM-MSC cell line employed, or CM from such cells, provided no osteogenic advantage over the use of HUCPVCs alone.