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Aim: This laboratory study aimed to investigate the effects of three endodontic biomaterials; MTA‐HP, iRoot‐BP‐Plus and ACTIVA on the proliferation, adhesion and osteogenic differentiation of human Dental Pulp Stem Cells (hDPSCs). Methodology: The hDPSCs were isolated from the dental pulps of 21 patients scheduled for surgical extraction of their impacted third molars. The MTT assay was used for assessing cellular proliferation. Ninety‐six‐well plates were used and the experiment was repeated four times under the same condition and the assay was done in triplicate. Four groups were assigned in which the hDPSCs were cultured in complete media only and considered as negative control. Whilst in the 2nd, 3rd and 4th groups, the cells were treated with CM supplemented with 1.5 μl MTA‐HP (CM‐MTA, iRoot‐BP‐Plus (CM‐BP), and ACTIVA(CM‐AC) extracts, respectively. Attachment adhesion and growth morphology of hDPSCs were observed using SEM and the osteogenic differentiation assay was evaluated by Alizarin red stain test (ARS). The data of proliferation and osteogenic differentiation were analysed using two‐way ANOVA followed by Tukey's post hoc multiple comparison test. A p‐value < 0.05 was considered significant to analyse the differences amongst the means of groups. Results: Both CM‐MTA and CM‐BP groups were associated with a significant increase in hDPSC proliferation in comparison with CM‐AC and CM groups (p = 0.001). hDPSCs exhibited a greater cellular attachment to iRoot‐BP‐Plus surfaces followed by MTA‐HP, whilst less attachment was observed in the ACTIVA group. Moreover, at day 7 there was a significant difference in formation of mineralizing nodules; CM‐BP, CM‐MTA and CM‐AC groups respectively (p = 0.001). Whilst there was no significance of difference between CM‐AC and CM groups (p > 0.05). Conclusions: In a laboratory setting, ACTIVA, MTA‐HP and iRoot‐BP‐Plus promoted hDPSCs proliferation, mineralization and attachment, which may explain their in‐situ success as endodontic biomaterials. [ABSTRACT FROM AUTHOR]

Natural bone is a unique nanostructured material made of collagen fibre matrix and hydroxyapatite (HA) nanocrystals, providing mechanical support and protection from the vertebrate skeleton. However, in severe cases like bone-deficiencies, bone needs to be 'externally' repaired. Initially, different biological solutions were developed in bone-guided regeneration. However, due to the limitations with the existing biological grafts, a lot of researches have been devoted toward biomaterials including metals, ceramics, and polymers. On the basis of the interface reactions between the implant and the surrounding tissues, these biomaterials may be classified as 'nearly inert' or bioactive. Interestingly, the bioactive materials exhibit a specific biological response, leading to the formation of a natural bonding junction between the bone and the implant during bone regeneration. Recently, a special attention has been paid to a new generation of bioactive materials, i.e. (nano)structured biomaterials composed of a bioresorbable polymer matrix reinforced with bioactive inorganic compounds. While (bio)ceramic component provides the bioactivity, these materials can be readily engineered in such a way that their resorption rate in the body match the formation rate of the new tissue. This review hence reports the different biological and non-biological solutions developed in bone-guided regeneration, with a special emphasis on polymer-based materials, and our recent results obtained in osseointegration The bone physiology, and its natural regeneration are also described. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary This study examined the morphological and compositional structure of bone–implant interfaces after in vivo implantation into the tibias of rabbits. The implants were composed of biodegradable polyhydroxybutyrate/polyhydroxyvalerate copolymer reinforced with synthetic hydroxyapatite (HA) particles. Optical and scanning electron microscopy techniques were used, including energy-dispersive X-ray analysis. The interface was found to be morphologically, biologically and chemically active throughout the period of study. There was a strong tendency to rebuild the bone structure at the interface after implantation, independent of the composition of the implant, but direct bone bonding with the implant depended on the bioactive nature of the interface, as represented by the HA particles. At all implantation times, lamellar bone formed at the interface and replaced degrading polymer matrix, while engulfing HA filler particles. In regions about 50–100 from the interface, the bone region displayed an osteon organization. Osteoblasts and osteocytes were identified throughout the interface region. The thickness of the newly formed bone significantly increased over the period of the experiment from about 130 µm at 1 month to about 770 µm at 6 months. Materials that behave in this manner may be useful in some bone replacement therapies. [ABSTRACT FROM AUTHOR]